Guidebook for Air Cargo Facility Planning and Development (2015)

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28 The intent of this chapter is to provide airport planners with a planning and development framework that can be used to guide airport decision makers in planning and developing air cargo facilities. This framework is intended to be applicable to a range of airports and facility types based on current conditions at airports, forecasted change, and the metrics presented in this chapter. This chapter also provides guidance for development and implementation of a strategic development plan for airports to accommodate air cargo volumes in the future. The methodology for developing an air cargo strategic development plan is much the same as the process employed for air cargo in development of an airport master plan. 4.1 Air Cargo Planning Challenges Airport planners face the challenges of designating land for air cargo facilities, planning for air cargo facilities, and, when needed, choosing whether to construct or renovate air cargo facilities. The absence of reliable air cargo forecasts to assist them and the current uncertainty in the future of air cargo volumes do not absolve airport planners of ensuring that there is enough air cargo facility capacity to meet future demand; these factors just make their jobs more difficult, and they must rely more heavily on other indicators and methods for determining their airports’ needs. One overriding complexity in meeting these challenges is the fact that there are significant dif- ferences in the air cargo facilities between large-hub international gateway airports and domestic airports. While large-hub international gateway airports can have a significant portion of their air cargo flown in on international passenger and cargo-only airline flights, many domestic air- ports have the majority of their air cargo flown in and out of their airports by integrated express carriers. As a result, cargo facilities at domestic airports are quite simplified when compared to complex cargo facilities at international gateway airports. One common thread between the various sizes of airports, however, is that at most airports some air cargo volume is still trans- ported on domestic passenger airline aircraft, and airports need to have appropriate air cargo facilities to accommodate them. The difference in the volume of air cargo handled between large international gateways and smaller domestic airports produces a wide range of air cargo facility requirements at airports across the nation. 4.1.1 Air Cargo Strategic Development Plan An air cargo strategic development plan can be used by airport planners to evaluate the vol- ume of air cargo and mail forecasted to pass through an airport. The critical elements of the plan are development of a realistic air cargo volume forecast and determination of how much land and air cargo facility capacity are required to accommodate forecasted air cargo. With air cargo volumes down by a substantial percentage since the beginning of 2000, some airports have C H A P T E R 4 Planning Considerations and Metrics

Planning Considerations and Metrics 29 surplus air cargo capacity that could accommodate future increases in air cargo volume but may require relocation of users to larger surplus facilities or renovation of existing facilities. Other airports may need to create additional air cargo facility capacity through the designation of land and construction of air cargo facilities. Whatever the case, airport planners should, through the development of a strategic development plan, determine what action is required to accommo- date the forecast. 4.1.1.1 Determining Land and Facility Requirements Once the air cargo forecast has been developed, facility utilization ratios (discussed in a sub- sequent section) can be applied to determine if additional land needs to be designated on the airport for air cargo facilities or if air cargo facilities need to be constructed or expanded. In the short term, input from the airlines, integrated express carriers, and ground handling companies is critical. In the longer term, where specific long-term requirements of the airlines, integrated carriers, and cargo handlers are not available, airport planners should rely on the air cargo fore- cast and the facility utilization ratios to plan for additional air cargo facilities or designate addi- tional land for air cargo facilities. Depending on the volume of air cargo handled and whether the airport is an international gateway or a domestic airport, there are several different air cargo and associated support facility sizes required. 4.1.1.2 International Gateway Airports International gateway airports are quite different from domestic airports. In addition to the integrated express carriers’ air cargo facilities, these airports may have large U.S.-based airline hubs and several international flag carriers that carry a substantial amount of air cargo in the belly of their passenger aircraft or operate cargo freighters. At these airports, it is common for the airlines and integrated carriers with larger operations to have their own dedicated air cargo facilities that can be as large as 200,000 ft2 and have large aircraft parking aprons and as many as 50 truck dock doors. For those operating freighters, it is common to have large aircraft parking aprons capable of parking two to ten B747Fs, along with space for B747-8s in coming years. Some airports have constructed large common-use air cargo parking aprons for freighters where the load/unload functions are performed rather than having exclusive-use aircraft parking aprons located directly behind their air cargo facilities. In this case, the air cargo is transported by tug from the aircraft to/from the respective air cargo facility, which is ideally located within a reason- able proximity of the air cargo parking apron. In addition, at many international gateways there are ground handling companies that pro- vide cargo warehousing services for a single airline or multiple airlines, either in their own facil- ity or a client’s facility that needs air cargo warehouse space, ramp space to store ground support equipment, and facility space to maintain ground support equipment. 4.1.1.3 Domestic Airports At domestic airports, there are air cargo facilities that accommodate the needs of passenger airlines’ belly cargo in addition to the integrated express carriers’ facilities. Usually the airlines’ air cargo warehousing areas are situated in multi-tenant facilities with truck dock doors on one side and access to the airport operations area on the other side. The air cargo facility usually divides the airport operations area from airport land outside of the airport operations area. Often the airports build these facilities and lease a portion or bay to the airlines. The airlines in many cases construct administrative offices for their air cargo support staff within their air cargo facility and install secured areas for bonded shipments, high-value shipments, and air- craft parts storage. At smaller airports where airlines handle around 1,000 tons of cargo per year, airports will have one airline air cargo building consisting of about 50,000 ft2 with eight to ten bays of about

30 Guidebook for Air Cargo Facility Planning and Development 6,500 ft2, with two truck dock doors and access to the airport operations area. In addition to the airline air cargo facility, many domestic airports have the vast majority of the air cargo handled by integrated express carriers. At smaller domestic airports, the integrated carriers can handle as much as 50,000 tons of air cargo per year. The integrated express carriers either have a smaller sortation facility on the airport and transport much of the air cargo off airport to a larger regional sortation facility, or they have a larger facility on the airport for sortation. The integrated express carriers may require sufficient aircraft parking apron to park one or two B757F. For example, if a warehouse needed 50,000 ft2, the truck parking space required would be 90,000 ft2 (50,000 × 1.8). Using the truck dock and door ratios for the same-size facilities results in 33 doors and docks (50,000/1,500). In planning for the airlines and integrated express carriers, the amount of space required to maintain the GSE also needs to be considered. If the GSE cannot be maintained within the air cargo facility, then additional facility space is required elsewhere at the airport. 4.2 Air Cargo Area Land Use Considerations 4.2.1 Cargo Terminal Facilities Location Strategies A conventional air cargo terminal servicing passenger airline cargo operations should be located as close to the passenger terminal as possible to minimize the distance required to tug the cargo from the building to the passenger terminal. The location should allow space for expanding the facilities when demand warrants, commensurate with master planning processes and facility requirements. New facilities must have geotechnical site constraints; earth-moving, drainage, utilities, and so forth must be taken into consideration. A cargo hub facility for an integrated express carrier should, in contrast, be separated as far as possible from other facilities unless there is likely to be substantial cross transfer with the combination passenger carriers. Many integrators prefer to be on the opposite side of the runway, with their own taxiway systems for both air cargo hubs and cargo terminal buildings. The all-cargo terminal for freighters should also be as close to the runway as possible, without infringing on any of the runway transitional surfaces, either from the building or from the tails of parked aircraft. Based on analysis of case study airports, the locations of air cargo terminals followed three basic layout patterns: • Split cargo areas. Passenger belly cargo building(s) in proximity to passenger (pax) terminal but separated from all-cargo terminal area—Austin Bergstrom International Airport (AUS). • Contiguous cargo area. Passenger belly cargo building(s) in proximity to pax terminal and adjacent to all-cargo buildings—Washington Dulles International Airport (IAD). • Scattered cargo areas. Passenger belly cargo building(s) in proximity to pax terminal but sepa- rated from a scattered all-cargo terminal area(s)—Indianapolis International Airport (IND). Air cargo that is transported in passenger aircraft is off-loaded and loaded at the passenger ter- minal gate. It is typically transported to the cargo terminal for handling by a tug-and-cart/dolly system (also referred to as cargo train) or flatbed truck over a restricted service road accessible only to cleared personnel. The transit time to and from the passenger terminal is an important planning consideration. At IND, a newly constructed midfield passenger terminal was separated from the existing cargo area by a distance of 3 miles, with a tug time of greater than 15 minutes on average. A new passenger belly cargo complex was constructed in proximity to the new IND passenger terminal to remedy this problem. At Miami International Airport, a cargo access tunnel built under diagonal Runway 12-30 is used to transport belly cargo to/from the east side passenger belly cargo terminal area to the midfield passenger terminals of the airport. The tunnel

Planning Considerations and Metrics 31 has cut the trip down from an average of 45 minutes to less than 15 minutes, and from 7 miles to 2 miles. The Miami example is provided to identify the level of importance in providing quick access from the belly cargo area to the passenger terminal. It is important to note that the speed limit on air operations areas (AOAs) is typically 25 mph in driving lanes and 5 mph in close proximity to aircraft, buildings, and construction in progress. It is also important for the airport planner to ensure that there is enough room on the apron and within the building for the tug cargo trains to stage, load, unload, and pass each other with a safe amount of clearance. This results in a safer work environment for the employees and less wear and tear on the equipment, ramp area, and cargo buildings. Conversations with operators of belly cargo terminals indicated that tug time to the passenger terminal is of paramount importance to the carrier. Based on evidence provided by carriers and the research associated with this study, a table of viable tug times between belly cargo areas and passenger terminals was developed based on airport cargo traffic volumes. Generally speaking, the larger the airport, the greater the tug driving time from cargo building to passenger terminal. Table 4-1 identifies viable tug times for airports based on cargo tonnage. 4.2.1.1 Example Split Cargo Areas Cargo facilities at AUS are a good example of a split cargo areas location strategy. The airport has two cargo development areas. The belly cargo area is located 0.6 miles from the passenger terminal, and the airport’s north cargo area (from the center of the passenger terminal ramp), designed for all-cargo operators, is located directly at the front of the airport, on Highway 71, the main road leading to central Austin. The north cargo area provides immediate access to the airport’s taxiway system and Runway End 17 R. Both cargo areas share the same entrance, appropriately named “Cargo Road,” and have a prominent position at the airport site. Figure 4-1 identifies the belly cargo and all-cargo areas at the airport. The city of Austin chose to have 100% of its cargo facili- ties developed by third-party developers—one of the few completely privatized airport sectors in the country. Three different developers built and operate the facilities to this day. Few airports have such competition, and the result is a wide range of options and a focus on the customers’ requirements. 4.2.1.2 Example Contiguous Cargo Area Cargo facilities at IAD are a good example of a contiguous cargo area location strategy (Fig- ure 4-2). Contiguous cargo areas have passenger belly cargo buildings in proximity to the passen- ger terminal and are adjacent to all-cargo buildings. Also, in designating land for future air cargo development, airports can reduce the overall cost of developing an air cargo facility by designing a common-use aircraft parking apron. Common-use aprons such as these are eligible for FAA grant funding, which removes much of the cost of the aircraft parking apron from the facility develop- ment cost. ACI-NA Airport Grouping* Annual Volume of Cargo Viable Tug Driving Time Between Belly Cargo Area and Passenger Terminal Small 100,000 or fewer metric tons 1 to 5 min Medium 100,000–499,999 metric tons 5 to 10 min Large 500,000 or greater metric tons 10 to 20 min *The 2002 ACI-NA Air Cargo Facility and Security Survey separated airports into three groups, which the research team followed. ACI-NA = Airports Council International–North America. Table 4-1. Viable tug driving time.

32 Guidebook for Air Cargo Facility Planning and Development Dulles’ air cargo facilities primarily consist of four relatively large cargo buildings totaling about 500,000 ft2 of space that are all contiguous to each other. The cargo is carried through belly cargo on passenger airlines, with the exception of FedEx Express, UPS, and DHL. Metropolitan Washington Airports Authority (MWAA) is also seeking to attract all-cargo carriers with trans- oceanic international routes. It is noteworthy that MWAA has 400 acres on the west side of the airport earmarked for air cargo expansion to double the cargo capacity. Should this be developed, the airport would fall into the split cargo areas strategy. 4.2.1.3 Example Scattered Cargo Area Cargo facilities at IND are a good example of a scattered cargo areas location strategy (Fig- ure 4-3). As stated previously, a newly constructed midfield passenger terminal at IND was separated from the existing cargo area by a distance of 3 miles and a tug time of greater than Source: Google Earth Pro, CDM Smith Analysis. Belly cargo area North cargo area Pax terminal Figure 4-1. Austin Bergstrom International Airport— cargo area location. Source: Google Earth Pro, CDM Smith Analysis. Cargo area (Belly and all-cargo) Passenger terminal area Figure 4-2. Dulles International Airport—cargo area location.

Planning Considerations and Metrics 33 15 minutes on average. A new passenger belly cargo complex was constructed in proximity to the new IND passenger terminal to remedy this problem. The distance between the new belly cargo area and the center of the midfield passenger terminal ramp is 1 mile, or less than 5 minutes. 4.3 Airside Cargo Facility Planning 4.3.1 Facility Requirements: Air Cargo Apron The role of the air cargo apron is to provide aircraft parking adjacent to the air cargo ter- minal building, provide sufficient space for ground handling operations for the loading and unloading of cargo aircraft as well as to service the aircraft, and provide sufficient space for the storage of GSE as well as ULD and pallet storage. For operations at international gateways and O&D domestic markets, the space must be large enough to park an optimal number of aircraft and accommodate aircraft tugs, cargo containers and trailers, cargo vehicles, mobile stairs, tail stands, and fueling vehicles or carts. For airports supporting integrated express hubs, the apron would include all the aforementioned attributes in addition to providing space for cargo sorta- tion, 53-ft tractor-trailers, and tail-to-tail cargo transfer and bypass containers. Some cargo aprons contain fixed equipment that includes cargo loading platforms and in- ground nose tethers. The air cargo apron must be relatively level and provide access to the airport’s taxiway system, and should be in close proximity to the airport’s runways in order to reduce taxi times. Some air cargo aprons may be located at areas of the airport without adjacent terminal buildings, but this is the exception and not the rule. Since large cargo aircraft will be parking on the apron, the asphalt or concrete pad must pro- vide sufficient strength to support these aircraft. Aircraft parking areas, also called “hard stands,” typically have weight-bearing strength greater than that of the taxiway system since aircraft will be positioned on these for longer periods of time. Hard stands are designed differently than taxi- ways since they require greater steel reinforcement and more stringent expansion joint systems. Hard stands need to be designed by aircraft type and take into consideration gear spacing and Source: Google Earth Pro, CDM Smith Analysis. Passenger terminal FedEx regional Vacant USPS mail facility CargoLux ramp New belly cargo area Vacated cargo area Ad hoc cargo area Figure 4-3. Indianapolis International Airport—cargo area location.

34 Guidebook for Air Cargo Facility Planning and Development number of wheels; therefore, the aircraft types that are anticipated to operate in the cargo area need to be accurately forecasted by the airport planner. 4.3.2 Critical Aircraft Implications for Apron The development of airport facilities is affected by the demand for those facilities, typically rep- resented by total based aircraft and operations at an airport, and the type of aircraft that will make use of the facilities. In general, airport infrastructure components are designed to accommodate the largest or most demanding type of aircraft (referred to as the critical aircraft) expected to use the infrastructure on a regular basis (at least 500 annual operations). Once the critical aircraft has been identified, its approach speed and wingspan are used to characterize the runway design standards and specifications required for an airport to safely and effectively serve that aircraft. The FAA groups aircraft into aircraft categories and Airplane Design Groups (ADGs) based on their approach speed and wingspan, respectively. The criteria for these categories are pre- sented in Tables 4-2 and 4-3. After identifying an airport’s critical aircraft, it is possible to determine the Airport Reference Code (ARC). The ARC system is a coding system that relates airport design criteria to the opera- tional and physical characteristics of the airplanes that are intended to operate at an airport. An ARC is a composite designation based on the aircraft category and ADG of the critical aircraft. Critical aircraft not only govern the size of the runway design but also govern the design of the taxiway system, apron, and other pavements’ strength and parking dimensions. For commercial service airports, critical aircraft are typically large passenger aircraft serving the airport, but it is not unusual for a specific cargo aircraft operating on a scheduled basis to be the critical air- craft. For example, at Indianapolis International Airport the largest passenger aircraft serving the Aircraft Category Approach Speed Typical Aircraft A <91 knots Cessna 172 B 91 to <121 knots Cessna Citation III C 121 to <141 knots CRJ, Lear 25 D 141 to <166 knots Airbus A380, Boeing 747 E 166 knots or more Future aircraft Source: FAA Advisory Circular (AC) 5300/13. Table 4-2. Aircraft categories. Airplane Design Group Wingspan Typical Aircraft I <49 ft Cessna 172, Cessna 401 II 49 to <79 ft Falcon 50, Gulfstream III III 79 to <118 ft B-727, B-737, DC-9 IV 118 to <171 ft A-300, B-757, B-767, DC-10 V 171 to <197 ft B-747 VI 197 to <262 ft A380, B747-8 Source: FAA AC 5300/13. Table 4-3. Airplane design groups.

Planning Considerations and Metrics 35 airport is the B737-800, while the largest cargo aircraft operating at the airfield on a scheduled basis is Cargolux’s B747-400. This aircraft may be upgraded to the B747-8 in the near future. 4.3.3 Role of Aircraft Manufacturers in Airport Master Planning Space for large cargo aircraft parking, hardstand usage, ground operations, and runways is best measured against the needs of the specific cargo aircraft being accommodated rather than forecasted tonnage throughput. It is at this point in the planning process that airport planners work most closely with the airlines and airplane manufacturers. To assist airport planners and engineers, Boeing produces airport planning manuals, entitled Airplane Characteristics for Airport Planning (http://www.boeing.com/boeing/commercial/ airports/plan_manuals.page), for all Boeing- and Douglas-designed commercial airplanes. These manuals describe specific airplane characteristics such as dimensions, performance, ground maneuvering, terminal servicing, jet-engine wake and noise, and pavement requirements. Air- bus has a similar airport planning manual for its family of aircraft (http://www.airbus.com/ support/maintenance-engineering/technical-data/aircraft-characteristics/). These manuals pro- vide information on basic airplane runway-length requirements, performance, typical interi- ors, pavement requirements, and jet-blast attributes. The Boeing Airplane Characteristics for Airport Planning manuals are made available by the manufacturer for any transport-category airplane having maximum takeoff weights of 35,000 lb (15,875 kg) or more (http://www.boeing. com/assets/pdf/commercial/airports/faqs/arcandapproachspeeds.pdf). Airlines, airports, and airplane manufacturers together walk a fine line, balancing the desire for increased airplane capacity, range, and operating economy with the need for airport improve- ments and modifications. 4.3.3.1 Cargo Apron Aircraft Space Requirements Cargo aircraft are commonly parked adjacent to the air cargo terminal building perpendicular or on a diagonal to the building. There are instances where the cargo apron is designed for parking the aircraft parallel to the building, but straight in at perpendicular is the most typical configura- tion. The aircraft should be parked as near as possible to the freight terminal in order to reduce the amount of ground traffic movement. The distance between the nose of the aircraft and the terminal exterior wall will vary depending on the size of the aircraft and whether it has a nose-loading door. Airport planners must consider the entire fleet of aircraft planned to use the cargo apron and any equipment that may need to operate in front of the aircraft. Sufficient length and maneuver- ing space must be available for aircraft tugs and towbarless tractors, and this is dependent on the position of the nose gear relative to the aircraft nose. Also, sufficient space must be provided for loading equipment operating in front of a nose-loaded cargo aircraft and clearance for the nose cone in the upright position. Defining the minimum distance needed between the aircraft nose and a structure or other barrier is critical to ensuring that adequate apron depth is provided to fully accommodate parked aircraft within the apron area. Adequate separation is needed between the wingtips of aircraft occupying adjacent parking positions as well as between wingtips and any fixed or movable object. The cargo aircraft parking apron requirement should be calculated based on the number of aircraft that are projected to be simultaneously parked on the apron and using the wingspan sizes of the aircraft types projected in the air cargo fleet mix along with allowances for wingtip clearances (25 ft between aircraft and objects). Table 4-4 provides separation distances from the aircraft nose to the rear wall of the terminal building as well as separation distances from aircraft wingtips and service roads. It is common to provide 5 ft of clearance between the wingtip of a parked aircraft and the edge of the marked service road to protect against vehicles that may deviate from the marked roadway.

36 Guidebook for Air Cargo Facility Planning and Development Another factor to be considered by airport planners is that when planning/designing new aprons or modifying existing aprons, blended-wing/-winglet technology, which adds to the length of an aircraft’s wingspan, needs to be taken into account. Blended-wing technology is available as a retrofit to an existing aircraft fleet and as an option on new aircraft. Airport planners must be aware of the variety of cargo aircraft operating on a scheduled basis at airports throughout the United States. Table 4-5 provides a list of cargo jet aircraft typically operating at U.S. airports on a scheduled basis as well as each aircraft’s ADG, which categorizes Separation Distances Aircraft Design Group1 III to VI Aircraft w/ Nose Door2 (B747, Antonov 124) Minimum nose-to-structure distance in linear feet 55 80 Minimum wingtip-to-object distance in linear feet 25 25 Minimum wingtip- and tail-to-service-lane distance in linear feet 5 5 Minimum tail-to-taxi-lane-edge distance in linear feet 75 75 Notes: (1) As noted in ACRP Report 96: Apron Planning and Design Guidebook, for passenger aircraft the FAA recommends minimum nose-to-building distances of 15 ft for ADG III aircraft, 20 ft for ADG IV aircraft, and 30 ft for ADG V aircraft, but cargo aircraft require larger buffers. (2) Some freighter aircraft models are equipped with a nose door that allows cargo loading/unloading. Source: CDM Smith. Table 4-4. Aircraft-building separation distances. Jet Cargo Aircraft AAC ADG Fe dE x Ex pr es s U PS A BX A m er ic an T ra ns p. In t'l So ut he rn A ir A m er ije t C en tu ri on A ir C ar go A TL A S Po la r A ir C ar go C ar go lu x A vi an ca K or ea n A ir C at ha y Pa ci fic Airbus A300-600 C IV Airbus A310-200 C IV Airbus A310-300 C IV Airbus A330-200F* C V Boeing 727-200* C III Boeing 747-200 D V Boeing 747-400* D V Boeing 747-400ERF D V Boeing 747-8 D VI Boeing 737-700C* C III Boeing 757-200 C IV Boeing 767-200 C IV Boeing 767-300F D IV Boeing 777-200 C V Douglas DC-8-70 C IV McDonnell Douglas MD10 D IV McDonnell Douglas MD11 D IV Notes: ABX, American Transport International, and Southern Air contract extensively to DHL.*Includes winglets. Source: FAA AC 15/5300, carrier websites. Table 4-5. Representative sample of cargo jet aircraft and carriers operating at U.S. airports.

Planning Considerations and Metrics 37 aircraft by wingspan, and the FAA’s Aircraft Approach Category (AAC). The AAC categorizes aircraft by approach speed when landing. Aircraft in Category A approach the runway at much slower speeds than aircraft in Category D. Table 4-5 takes only into consideration all-cargo air- craft and does not include passenger aircraft. When planning for cargo apron space, the airport planner essentially has two methods for determining the amount of cargo apron space needed. The planner can use a throughput metric based on tonnage handled on the ramp on an annual basis or on a peak-period basis. The plan- ner can ascertain from the airport’s cargo carriers their anticipated aircraft types that are likely to operate on the airfield during the planning period. A typical master plan requires at least a 20-year planning period for facilities, while an air cargo carrier typically plans its fleet in 5- to 10-year increments. Planners may also be required to modify or reconfigure existing cargo ramp space to support a cargo carrier when a change in aircraft types is imminent. While this prospect does not directly involve master planning, it falls into the airport planner’s day-to-day planning responsibilities. Table 4-6 provides the airport planner a tool to use for determining the amount of space required for cargo aircraft parking. The total space required per aircraft type takes into consideration the aircraft’s wingspan as well as overall length. Buffer space is also included in the total square footage requirements to separate aircraft from other aircraft as well as buildings and service lanes. Buffer space allows space for aircraft service and GSE storage and utilization. While the FAA does not specify cargo apron design standards, Airports Council International–North America (ACI-NA) and Airlines for America (A4A) do provide apron facility guidelines. ACRP Report 96 provides guidelines on apron planning but is primarily focused on airline terminal apron areas (Quinn 2013). Aircraft tail height is provided to assist in determining line-of-sight issues as well as potential airspace penetration issues. Planners should allow 25 linear feet between aircraft wingtips when designing aircraft parking positions on the apron as well as sufficient dis- tance between the nose of the aircraft and any structures. Table 4-6 includes the recommended distances based on ADG presented in Table 4-5. Common Jet Cargo Aircraft AAC ADG Length Wing- span Tail Height Length Including Nose/Tail Buffers Wingspan + 25’ Total Area (ft2) Airbus A300-600 C IV 177.0 147.1 55.0 307.0 172.1 52,834.7 Airbus A310-200 C IV 153.1 144.0 52.1 283.1 169.0 47,843.9 Airbus A310-300 C IV 153.1 144.0 52.1 283.1 169.0 47,843.9 Airbus A330-200F*^ C V 191.5 197.8 57.1 321.5 222.8 71,630.2 Boeing 727-200* C III 153.2 109.3 34.9 283.2 134.3 38,033.8 Boeing 747-200^ D V 229.2 195.8 64.3 359.2 220.8 79,311.4 Boeing 747-400*^ D V 231.9 213.0 64.0 361.9 238.0 86,132.2 Boeing 747-400ERF^ D V 232.0 212.9 64.3 362.0 237.9 86,119.8 Boeing 747-8^ D VI 250.2 224.4 62.7 380.2 249.4 94,821.9 Boeing 737-700C* C III 110.2 117.5 41.7 240.2 142.5 34,228.5 Boeing 757-200 C IV 155.2 125.0 45.1 285.2 150.0 42,780.0 Boeing 767-200 C IV 159.1 156.2 52.9 289.1 181.2 52,384.9 Boeing 767-300F D IV 180.1 156.2 52.6 310.1 181.2 56,190.1 Boeing 777-200 C V 209.0 199.8 61.5 339.0 224.8 76,207.2 Douglas DC-8-70 C IV 187.3 148.3 43.3 317.3 173.3 54,988.1 McDonnell Douglas MD-10 D IV 183.0 165.0 58.8 313.0 190.0 59,470.0 McDonnell Douglas MD-11 D IV 202.1 170.5 58.8 332.1 195.5 64,925.6 *Includes winglets; ^assumes nose-door aircraft. Source: FAA AC 15/5300, carrier websites. Table 4-6. Parking space requirements for cargo jet aircraft operating at U.S. airports.

38 Guidebook for Air Cargo Facility Planning and Development Turboprop aircraft are also used to transport air cargo on a scheduled basis. The majority of these operations are related to regional cargo aircraft that feed cargo to awaiting integrated express cargo jets. In some instances these aircraft fly directly to an integrated express cargo hub. Table 4-7 identifies turboprop cargo aircraft, their AAC and ADG category, and carriers that currently operate these aircraft for cargo operations. It is noteworthy that these aircraft may be located on an integrated express origin-and-destination station which is supported by the carri- ers’ staff, or these facilities may have a small cargo shed, hangar, or tie-down spot on the air cargo apron. These aircraft may also be solely supported by the airport’s fixed-base operator (FBO) and, subsequently, are reliant on FBO staff to load and fuel. These operations often take place on the general aviation apron and blend in with the other general aviation traffic. An integrated express operator would likely drive its truck(s) to the aircraft for loading and unloading. Many of the regional cargo aircraft are contracted carriers, and their aircraft may be painted in the client’s logo and paint scheme. Mountain Air Cargo, for example, is a contractor to FedEx Express and flies C208 aircraft with FedEx branding. Where regional cargo aircraft feed into the cargo jet, the apron area may have parking positions for large cargo jets and several turboprop feeder aircraft. Table 4-8 provides the airport planner a tool to use for determining the amount of space required for regional cargo aircraft parking. The total space required per aircraft type takes into consideration the aircraft’s wingspan and its overall length. A 12.5-ft buffer space is also included in the total square footage requirements to separate aircraft from other aircraft as well as buildings. This area provides sufficient space for aircraft parking and servicing and loading the aircraft. Planners should allow 25 linear feet between aircraft wingtips and sufficient distance between the nose of the aircraft and any structures. 4.3.4 Air Cargo Facility Requirement Ratios The facility requirements element of the airport master plan summarizes a technical analysis of the aviation and allied facilities that will be required to accommodate the aeronautical activity (passenger, air cargo, and general aviation/corporate) identified in the aviation forecasts element. During the airport master planning process, planners determine what (if any) additional facili- ties will be required to accommodate forecast activity. This task begins with an assessment of the ability of existing facilities to meet current and future demand. If they cannot, planners must Common Cargo Turboprop AAC ADG W ig gi ns Em pi re M ou nt ai n A ir Ca rg o A m er ifl ig ht A ir Ca rg o Ca rri er s A lp in e A ir ATR42 B III ATR72 B III B1900 B II Beech B99/C99 B I Cessna Caravan 208 B II DeHavilland DASH 8 A III EMB-120 B II Fairchild Dornier SA-227DC B III Metroliner III B I SHORT SD3-60 B II Source: FAA AC 15/5300, carrier websites. Table 4-7. Regional turboprop cargo aircraft/carriers operating at U.S. airports.

Planning Considerations and Metrics 39 determine what additional facilities will be needed to accommodate the unmet demand. This section is normally referred to as the facility requirements section of a master plan document. Air cargo warehouse, ramp, GSE storage, and parking area data collected are used in the facility requirements analysis to define planning metrics and ratios into functional relationships related to air cargo facilities. ACRP Project 03-24 identified two primary cargo building throughput formulas used in the master plan process: (1) area per annual ton ratio, and (2) annual tonnage per area ratio (TAR). • Area per annual ton ratio. Many master plans indicate that average building throughput rates at U.S. airports vary between 1.0 and 2.5 ft2 per annual ton. A throughput rate of 1.0 ft2 per annual ton typically indicates that the facilities are well utilized and some near-term expan- sion may be required. The higher rate of 2.5 ft2 per annual ton indicates that existing tenants have ample—even surplus—space. These throughput rates, however, are all-inclusive and incorporate a wide variety of air cargo occupants such as passenger airlines, all-cargo carriers, integrated express carriers, and third-party providers. This analysis breaks out throughput ratios by air cargo carrier type and airport role—either international gateway or domestic market. It is also important to point out that this analysis does not take into consideration air cargo that bypasses the cargo building and is trucked directly to aircraft on ramps as well as any cross-docking operations taking place within the air cargo building. • Annual tonnage per area ratio. Another method of determining air cargo warehouse area is to use a tonnage per area ratio. The TAR is defined in units of total annual tons of freight per square foot of cargo floor space. This ratio can then be compared to a derived maximum TAR value, which will typically range from 0.5 tons/ft2 to 3.0 tons/ft2, with the latter being representative of a highly efficient automated sort operation. Achieving a higher value of TAR is dependent on the degree of mechanization, the layout of the building, the type of cargo (e.g., international versus domestic, refrigerated), and how the cargo is typically packaged for shipping (e.g., pallets, containers). The Air Cargo Facility Planning Model presented in Chapter 9 uses this method (annual tons per square foot ratio), which presents the less efficient facilities with a lower value. 4.3.5 Utilizing Facility Planning Metrics for Cargo Apron Design Airports were analyzed in this study to estimate the annual ton per square footage utilization of air cargo for warehouse ramp space and GSE storage space. Truck and automobile parking Common Cargo Turboprop AAC ADG Length Wing- span Tail Height Length Including Nose/Tail Buffers Wingspan + 25’ Total Area (ft2) ATR42 B III 74.5 80.6 24.9 109.5 105.6 11,563 ATR72 B III 89.2 88.8 25.0 124.2 113.8 14,128 Beech B1900 B II 57.9 58.0 15.5 82.9 83.0 6,881 Beech B99/C99 B I 45.0 45.9 14.3 70.0 70.9 4,964 Cessna Caravan 208 B II 42.0 52.1 14.8 67.0 77.1 5,166 DeHavilland DASH 8 A III 84.3 89.9 24.1 119.3 114.9 13,708 EMB-120 B II 65.6 65.0 20.9 90.6 90.0 8,154 Fairchild Dornier SA- 227DC B III 59.3 95.2 27.5 94.3 120.2 11,335 Metroliner III B I 59.5 46.2 16.7 84.5 71.2 6,016 SHORT SD3-60 B II 70.7 74.8 23.1 95.7 99.8 9,550 Source: FAA AC 15/5300, carrier websites. Table 4-8. Parking space requirements for regional turboprop cargo aircraft operating at U.S. airports.

40 Guidebook for Air Cargo Facility Planning and Development facility development is based on building size. Table 4-9 provides a facility requirements data matrix of ratios for cargo buildings, ramp area, and GSE storage based on the cargo operator types of: • Integrated express carriers, • Pax belly, and • Third-party providers/all-cargo carriers. Dedicated cargo apron space for passenger carriers is not presented since most passenger car- rier facilities do not have a need for designated air cargo ramp area to park aircraft since cargo for passenger carriers is typically tugged to the aircraft parked at the passenger terminal ramp. It is important to note that these ratios are generic in nature to provide high-level guidance for air cargo area facility planning and are not typically applicable to individual carrier practices, which will likely have substantial variations in space requirements. These ratios, however, pro- vide capacity requirements for air cargo activity at an airport. Carrier-specific utilization data should be obtained during the inventory process. 4.3.5.1 Ramp Throughput Analysis Ramp throughput rates are the standard measures to define the capacity of freight facilities; this rate is expressed in annual tons of freight per square foot of ramp. Airport master plans use several methods for determining ramp space. For example, one accepted planning criterion for cargo aprons is to allow 5 ft2 of apron per square foot of cargo building space (HNTB 2008). Another method is to use an average area per aircraft based on the fleet mix in the master plan cargo forecast. These parking areas incorporate standard wingtip clearances and allow room for GSE and a taxi lane to service the area. Both these ratios, however, often include ramps used for both aircraft parking and GSE storage and operating space. 4.3.5.2 Integrated Express Aircraft Parking Apron This analysis provides ratios for determining space requirements for both aircraft parking and GSE storage for a combined air cargo apron planning metric. These ratios are based on survey data from an extensive data collection effort. As presented in Table 4-9, cargo aircraft parking space utilization based on annual cargo tonnage throughput is approximately 0.19 annual tons per square foot for domestic cargo for integrated express carriers and 0.19 for the same carrier type at international gateway airports. Ratios for GSE are typically not broken out in a master plan’s facility requirements but are provided here. Cargo ramp or apron facility requirements in a typical master plan combine aircraft parking ramp areas and GSE storage areas. Since the data Integrated Express Pax Belly Third-Party Providers and All- Cargo Carriers Building Domestic 0.92 0.64 0.81 International gateway 0.37 0.64 0.81 Master plan review ratios* 0.93 0.63 0.57 Ramp Domestic 0.19 0.16 International gateway 0.19 0.91 GSE Storage General 0.57 0.36 1.11 *Various airport master plans from literature review. Source: CDM Smith. Table 4-9. Air cargo facility requirements ratio matrix.

Planning Considerations and Metrics 41 collection effort focused on data related to GSE spatial needs, this analysis provides GSE space ratios for integrated express carriers. 4.3.5.3 Integrated Express GSE Storage Apron The weighted average analysis related to average ton per square foot for integrated express carriers’ GSE storage requirements, located at both international gateway and domestic airports, is 0.57 annual tons per square foot. 4.3.6 Applying the GSE Storage and Aircraft Parking Ratios The air cargo facility requirements ratio matrix (Table 4-9) provides the metrics for convert- ing annual cargo tonnage flows into cargo aircraft parking and GSE storage area requirements. Simplified calculations based on empirical data from this study’s research can assist in providing an estimate of the air cargo apron requirements in a preliminary design stage. For example, the size of the apron area required for the typical cargo volume can be calculated by dividing the annual cargo volume by the throughput per unit of apron area. This methodology can be applied to current conditions at the airport as well as forecasted air cargo tonnage. Representative values for integrated express O&D station aircraft parking, based on the research and analysis of this project, are 0.19 U.S. ton/square feet per year for the U.S. domestic and international operations and 0.57 U.S. ton/square feet per year for GSE storage. (Note that the representative, or indicative, value is based on a series of measurements and is the one that is closest to the real value of the measurement. If one carries a series of measurements, the representative value will be their aver- age, excluding those outlier values that have proved to be far from the true value.) For example, if an airport had an integrated air express tenant moving 80,000 U.S. tons annually, it would require 413,600 ft2 (9.5 acres) of apron space to accommodate its aircraft operations (see Table 4-10). For the same amount of cargo volume, an additional 139,200 ft2 of apron space for GSE would be needed. Combining the two requirements results in 552,800 ft2 (12.7 acres) of apron to accom- modate the 80,000 annual tons. The integrated express industry operates on average 5.5 days per week; 80,000 annual tons then translates to approximately 559,400 pounds of inbound and outbound cargo per day, or about eight fully loaded B757s (inbound and outbound). Table 4-10 also provides metrics for converting annual cargo tonnage flows into cargo aircraft parking and GSE storage area requirements for third-party handlers and all-cargo carriers. Rep- resentative values for an all-cargo freighter station aircraft parking area are 0.91 U.S. tons/square feet per year for U.S. international operations and 1.11 U.S. tons/square feet per year for GSE storage. For example, if an airport had an all-cargo carrier tenant moving 80,000 U.S. tons annu- ally, it would require 87,912 ft2 (2.0 acres) of apron space to accommodate its aircraft operations (see Table 4-11). For the same amount of cargo volume, an additional 72,000 ft2 of apron space would be needed for GSE storage. Combining the two requirements results in approximately 159,912 ft2 (3.7 acres) of apron to accommodate the 80,000 annual tons. Apron Required (Square Feet) Apron Required (Square Yards) Apron Required (Acres) Integrated Express Carrier Annual Tonnage Ton/Ft2 Ratio Apron 80,000 / 0.19 = 413,600 45,956 9.5 GSE storage 80,000 / 0.57 = 139,200 15,467 3.2 Total 552,800 61,422 12.7 Source: CDM Smith. Table 4-10. Air cargo facility requirements ratio application: integrators.

42 Guidebook for Air Cargo Facility Planning and Development While passenger airlines do not have air cargo apron requirements related to parking of cargo aircraft, they do have pavement requirements related to the operations adjacent to their air cargo terminal facilities. A representative value for an air cargo terminal apron for passenger airlines is 0.36 U.S. ton/square feet per year for the United States. If a passenger airline terminal is moving 10,000 tons per year, it would require 27,777 ft2 of paved space (10,000/0.36) to accommodate tugs and cargo trains. An important factor that airport planners need to take into consideration related to the cargo tonnage throughput methodology is the industry practice of air cargo carriers sharing one aircraft to serve two markets. For example, UPS operates an Omaha–Cedar Rapids–Louisville route with a B757-200 aircraft, yet the Cedar Rapids station may only be allotted 30% of the capacity. When aircraft are shared in these types of situations, the annual volume does not necessarily translate into a corresponding ramp size. In other words, the aircraft serving the market may be larger than the market demands and thereby require a larger apron area than one would expect. That is why it is important for airport planners to interview the key cargo stakeholders in order to better understand their needs and plans for aircraft equipment anticipated to operate in the market. Several practices within the industry also affect the amount of space needed for aircraft parking. For one, at spoke airports many integrated express operators park their aircraft during the day on the apron and fly to their respective hubs at night where packages are sorted. But it is not unusual for integrators to only stop an aircraft in a market then fly on to its final destination where it remains parked all day. The airport planner then must take into consideration the peak hour of demand for cargo aircraft parking. In Casper, Wyoming, for example, FedEx Express schedules two B757s that arrive from the Memphis hub, but one continues on to Grand Junction, Colorado, and the other to Boise, Idaho. In addition, FedEx operates about six Cessna 208 feeder flights into the airport. All of these operations require considerable apron space for an airport with a relatively small market area. Also at Casper, UPS operates a single contracted Metro III aircraft, which is supported by the airport’s FBO and requires limited space on the general aviation ramp. The all-cargo freighter businesses may also share aircraft with airports in other markets. For example, Kalitta Air Cargo operates a B747-400 from Hong Kong to Rickenbacker International in Columbus, Ohio, which then continues empty to JFK International where it is loaded with backhaul to Hong Kong. Tonnage on this route then is only reflective of inbound cargo. These types of nuances within the industry may not necessarily translate well when applying the air cargo facility requirements ratio matrix, which emphasizes the importance of airport planners’ understanding of industry practices at their airports. 4.3.7 Cargo Apron Design Considerations Older versions of air cargo planning documents often made algorithmic associations between cargo building and ramp size on the basis of the payload capacity of aircraft. While still an Third-Party Handler and All-Cargo Carrier Apron Required (Square Feet) Apron Required (Square Yards) Apron Required (Acres) Annual Tonnage Ton/Ft2 Ratio Apron 80,000 / 0.91 = 87,912 9,767 2.0 GSE storage 80,000 / 1.11 = 72,000 8,000 1.7 Total 159,912 17,767 3.7 Source: CDM Smith. Table 4-11. Air cargo facility requirements ratio application: freighters.

Planning Considerations and Metrics 43 intuitively logical approach, it requires considerable more nuance than such a simplistic com- putation may suggest. The freighter fleet itself has changed dramatically since older methodologies were created, although smaller spoke markets may have been left largely unaffected as Cessna Caravan feeder aircraft flying one or two more daily operations would have less dramatic effects than large inter- national gateways that may have planned for earlier versions of the Boeing 747 freighter fleet to be the permanent workhorse of the industry. While only applicable to transcontinental gateways for now, airports have been challenged to either build or expand aprons to accommodate new, larger freighters, often having to sacrifice the number of positions in the process. While cargo building utilization rates can be raised by adding labor and automation, ramps are much less forgiving. Domestically, carriers have windows in order to meet the sortation operations at their regional and national hubs, so peak periods for aircraft on the ground tend to be bundled. Similarly, international carriers with transatlantic and transpacific operations will have their own windows, albeit possibly countercyclical to those of domestic operators (due to stage length and time zone differences). Further complicating the planning issues, partial freighters have become a useful tool for airlines that may not have enough demand in individual U.S. markets to justify a transpacific flight but can improve payloads by allocating portions to multiple markets, such that a freighter may stop in Atlanta and Dallas/Ft. Worth prior to refueling in Anchorage and returning to Asia. On a theoretical basis, cargo building demand should only be affected by the amount of payload dedicated to the local market. While it is also possible that the aircraft may be unloaded and loaded more quickly when only a portion is to be handled in a market, there is no similar effect on the ramp size required; the ramp must be large enough to accommodate the largest freighter that will use it. At least for near- to mid-term planning, flight schedules are critically important tools for ramp planning. While schedules are fluid and often seasonal, a single ramp position can be reused multiple times per day if schedules permit. For carriers and handlers, this is also true for labor and GSE utilization. As an example, a gateway that is almost exclusively either a trans- atlantic or transpacific gateway may anticipate lower utilization rates for ramp space as carriers will tend to require the same operating windows. Gateways with a healthy mix of transatlantic and transpacific freighters may be more able to reuse ramp positions. Gateways with multiple daily operations by a single international carrier will also tend to be able to reuse positions as the carrier typically is trying to meet multiple windows in its own schedule and will attempt to not have redundant flights on the ground. However, gateways at which an international carrier may have both passenger and freighter flights could easily have both all-cargo and belly cargo throughput in the cargo building concurrently. While much of the preceding focused on international gateways, planners at domestic cargo hub-and-spoke cities must also pay attention to integrator fleets and schedules. Declarations in late 2012 by FedEx signaled an intention to potentially fly larger domestic freighters but at lower frequencies and possibly fewer destinations served by air. Trucking would continue to be the beneficiary in terms of shares of domestic cargo transported by all modes. Some industry observers anticipate that UPS would likely follow suit. Therefore, U.S. airports should be prepared for the possibility that larger ramp positions may be required in the near- to mid-term, or alternatively that need could be diminished, depending on whether the market is a beneficiary or victim of the trend. Either way, the dominant cargo carriers at the majority of U.S. commercial airports are in a prolonged period of operational transition that will require airports to remain flexible in their planning and development of air cargo facilities.

44 Guidebook for Air Cargo Facility Planning and Development 4.3.8 Cargo Apron Markings The FAA usually does not control aircraft activity on aprons and does not publish guidance related to markings in the leased portions of the cargo apron. However, ACI-NA, the Interna- tional Air Transport Association (IATA), ICAO, and A4A do publish passenger terminal and cargo apron marking guidelines. Airports and carriers need to coordinate the development of a consistent cargo apron marking protocol and have it applied to all appropriate aircraft aprons. The following section contains a generalized discussion related to common air cargo apron markings and guidelines available to the airport planner. 4.3.8.1 Lead-in/Lead-out Lines Lead-in and lead-out lines are gate-specific pavement markings that allow an aircraft to taxi under its own power or be towed to a gate or aircraft parking position. When an aircraft is parked appropriately, the center of the aircraft fuselage will be centered above the marking on the pavement. These lines are typically yellow and are the same width as the taxiway/taxi-lane centerlines, but in certain instances, a lead-in line is in black to provide contrast for light-colored pavement such as concrete (see Figure 4-4). 4.3.8.2 Stop Lines Nose-wheel stopping points along a parking centerline are typically labeled by aircraft type (B-757, B727, etc.) and are provided to aid aircraft marshallers and aircraft tug drivers in posi- tioning aircraft. 4.3.8.3 Aircraft Safety Envelope Aircraft safety envelopes define the areas where no vehicles or GSE should be positioned unless they are specifically servicing the aircraft occupying that particular gate. These lines, also called “foul lines” by ramp workers, provide a necessary buffer from vehicles and equipment in Source: Google Earth Pro, CDM Smith analysis. Aircra safety envelope line Taxi-lane center line Hardstand gate ID number Taxi-lane edge Stop line Lead-in line Generic outline to illustrate aircra parking Light pole Figure 4-4. Air cargo ramp markings.

Planning Considerations and Metrics 45 the gate area that are servicing other aircraft on the ramp. The area outside the aircraft parking and service envelopes up to the cargo building face can be used for GSE parking, ULD storage, and other apron activities. Many cargo operators use only white markings to identify the air- craft safety envelope. A4A recommends 10 ft as the minimum distance that the safety envelopes should protect from any point on the aircraft. 4.3.8.4 Push-Back Area When an aircraft is parked perpendicular or diagonal to a cargo building, a tug vehicle must push it away from the structure to position it for access to the taxiway system. The push-back process may move the aircraft into the aircraft movement area, such as a taxi lane, and through the tail-stand roadway. [Movement areas are under the control of the FAA air traffic control tower (ATCT), whereas non-movement areas are not under ATCT control, but aircraft may be under the control of ramp tower controllers when in non-movement areas.] If there is ample space, it is ideal for airport planners to provide a push-back area to support aircraft departing from an apron, optimally without affecting airfield or apron area taxiing flows. The provision of an aircraft push-back area can be made to accommodate aircraft maneuvers, allowing aircraft to safely push back and start engines without adverse jet-blast impacts or without penetrating the movement area or encroaching on any apron taxi lanes used for the directional movement of aircraft. (Coordination with ATCT personnel would be required if penetration is unavoidable.) Figure 4-5 provides an example push-back area between the hardstand and the taxi lane. 4.3.8.5 Jet-Blast Fence Jet blast is the thrust-producing exhaust from a running jet engine and propeller wash pushed to the rear of the aircraft when it is in motion. Some air cargo aprons require jet-blast fences to deflect jet blast, propeller wash, and noise when taxiing to and from the cargo apron (Figure 4-6). Source: Google Earth Pro, CDM Smith analysis. Cargo building/warehouse Push back area Centerline taxi lane Push back tug Figure 4-5. Air cargo apron push-back area and process.

46 Guidebook for Air Cargo Facility Planning and Development 4.3.9 Ground Support Equipment GSE is the support equipment found at an airport, usually on the ramp, which is the servicing area by the terminal. This equipment is used to service the aircraft prior to and after air car- rier flights. As its name implies, GSE is there to support the operations of aircraft and involves ground power operations, aircraft mobility, and loading operations (for both cargo and pas- sengers). GSE used to service all-cargo aircraft and the facilities that support all-cargo aircraft operations are substantially different from those used in passenger terminal facilities and are usually best located in a designated cargo area. When ULDs are loaded onto the lower decks of aircraft, air cargo GSE is likely located on the passenger terminal apron. GSE related to air cargo on the passenger ramp will include tugs, dollies, and lower-deck loaders. 4.3.9.1 GSE Storage GSE storage areas are used to park and stage GSE when it is not in use. These areas are often located on the apron in close proximity to aircraft parking positions but outside the aircraft safety envelope. The position of aircraft parked on an apron typically provides large areas in front of its wings that are used for GSE storage and maneuvering. Prior to a flight’s arrival, GSE may be positioned by carrier personnel just outside the aircraft safety envelope to minimize aircraft access time. During periods on inclement weather and in latitudes where winters are severe, cargo carriers may opt to store motorized GSE in a cargo terminal building or hangar. Battery powered GSE with an electric motor will need access to power plug-in outlets during storage. 4.3.9.2 Stationary GSE When aprons consistently service one cargo aircraft type and park consistently at the same gate, it often makes sense for the carrier or ground handler to install affixed GSE. This would include mounted preconditioned air units, APUs, lower-deck loading units, and potable water supply cabinets. Nose-load docks may also be a fixed to the apron and lead out of the cargo terminal building. Some carriers also install covered side door loaders (as shown later in Fig- ure 4-10). The use of fixed equipment expedites ground handling and reduces congestion around the aircraft parking position by eliminating additional stand-alone carts or vehicles. 4.3.9.3 Mobile GSE Most GSE is mobile and is transferred to and from the aircraft while the aircraft is being ser- viced. Equipment that is pulled up to the aircraft may include tugs, belt loaders, cargo (baggage) carts, empty dollies, loaded dollies (with ULDs and pallets), loaders, fuel trucks, lavatory and potable water vehicles, stairs, main deck (nose-door) loaders, and air start trucks. Source: Google Earth Pro, CDM Smith analysis. Figure 4-6. Air cargo ramp jet-blast fence at SEATAC International Airport.

Planning Considerations and Metrics 47 4.3.9.4 GSE Use Generally speaking, the larger the gauge of cargo aircraft being serviced, the larger the number of vehicles required to service it, which increases demand for GSE storage. Figure 4-7 identifies GSE in position to service a Boeing 747 with a cargo nose door. 4.3.9.5 Security Gates The security of the apron is largely controlled by ensuring that only authorized individuals or vehicles are provided access through security gates at the edges of the AOA or in cargo buildings. Cargo security gates are primarily used by airline support vehicles, and entrance is gained by use of a magnetically coded card, lock and key, an electronic device, or a proximity badge. Access to service and cargo gates is restricted and typically requires cargo employees to complete specific training in order to obtain permission to use them. 4.3.9.6 Apron Lighting Artificial lighting on the cargo apron enables nighttime cargo operations at airports. By pro- viding nighttime illumination of the apron, air cargo aircraft handling, parking, and cargo sort- ing and processing are maximized. Safety and security are enhanced as well. There needs to be enough lighting on the apron to read labels, placards, and documents as well as to provide safety for ramp workers. Multiple zones of illumination can be achieved by the installation of both fixed and portable lighting equipment. Lighting is commonly affixed to the air cargo terminal building, and where aprons are extensive in size, light poles are used. Source: Boeing 2002. Figure 4-7. Air cargo GSE service areas for a B747.

48 Guidebook for Air Cargo Facility Planning and Development 4.3.9.7 Deicing Apron or Pads When aircraft are covered with frost, snow, or ice contamination on their wings and other critical aeronautical surfaces prior to departure, deicing fluid is applied to remove the contami- nation and to prevent the accumulation of snow or slush for a period of time. If an apron is not equipped with the proper deicing fluid collection system, deicing fluid recovery vehicles or glycol recovery vehicles are used to recover deicing fluids from the airport pavement. Deicing pads may also be located adjacent to cargo aprons to consolidate the deicing activity and collect fluids, which are piped into storage tanks for recycling. 4.3.9.8 Hydrant Fueling Hydrant fueling systems consist of a network of underground pipes from airport fuel farm tanks to cargo hardstand locations. Fuel is pumped through the hydrant via a fuel cart to transfer fuel from the hydrant fueling network to an aircraft. Hydrant fuel pits are to be located near air- craft fuel ports, which are typically under the aircraft wing. The vehicles or carts are positioned by air carrier or contracted fuel staff near the underground hydrant pit and connected to the aircraft fuel tank port via a fuel hose and pressure coupling system. Once the hydrant fueling system is connected to the cart and grounded, fuel is transferred to the aircraft from the under- ground pipe system. When no hydrants are available, fuel is transferred from a fuel truck to the aircraft via a fuel hose and pressure coupling system. 4.3.10 Ground Vehicle Access Apron service roads serve as the main vehicle circulation arteries in and around the air cargo terminal core and other apron facilities. The purpose of apron service roads is to channelize the movement of air cargo–related vehicles so that pilots know where these vehicles are and to prevent conflicts with aircraft or engine jet blast. 4.3.10.1 Head-of-Stand Road A head-of-stand road is located between the nose of the parked aircraft and a cargo building. This configuration allows for uninterrupted access to aircraft because vehicle movements are not stopped for aircraft entering or exiting a gate. With this configuration, vehicles and GSE can travel from storage/staging areas around the gate areas directly to aircraft for servicing without accessing taxiways or taxi lanes, having to wait for aircraft pushing back or pulling into a gate position, and without other potential interactions. Head-of-stand road alignments also tend to increase apron depth. Figure 4-8 shows an example head-of-stand road at the UPS cargo ramp at Dulles International Airport. It is noteworthy that head-of-stand roads require apron dimensions with greater depth, especially to accommodate aircraft tugs without interfering with vehicle movements on these roads. These roads may create conflicts with apron-level cargo ter- minal door exits for personnel and ground vehicles. Overall, the head-of-stand configuration enhances safety by limiting interactions between vehicles and moving aircraft. 4.3.10.2 Tail-Stand Road A tail-stand road is located at the tail of the aircraft where they are parked on the cargo apron and is at times referred to as an apron-edge service road because the road can delineate the limit of the leased areas. As shown in Figure 4-9, the layout of this type of service road usually reflects the physical limits of aircraft parking areas; it may also reflect the taxiway/taxi-lane alignment. Tail-stand roads can result in potential conflicts between vehicles and aircraft since aircraft must cross them to enter or exit gates. Figure 4-9 provides an example tail-stand road at the DHL cargo ramp at JFK International Airport. To avoid operational consequences, tail-stand service roads must be located outside all taxiway and taxi-lane object-free areas (OFAs) since penetrations of these areas can result in

Planning Considerations and Metrics 49 Source: Google Earth Pro, CDM Smith analysis. Head of stand road Cargo building GSE storage GSE vehicle parking Figure 4-8. Head-of-stand road and GSE storage configuration. Source: Google Earth Pro, CDM Smith analysis. Tail stand road/lane Center of taxi lane Cargo building Edge of taxi lane Figure 4-9. Tail-stand road and taxi-lane configuration.

50 Guidebook for Air Cargo Facility Planning and Development limitations on the size of aircraft that can use the affected taxiways/taxi lanes. On aprons with tail-stand roads located on each side of a taxiway or taxi lane, it is common for these tail-stand roads to be connected across the taxiway/taxi lane by a service road marked on the pavement to provide vehicles a defined route to cross pavement areas, which can be expansive. 4.3.10.3 Roads Between Cargo Terminal Buildings It is not uncommon for air cargo aprons to be supported by a vehicle pass-through road between air cargo terminal buildings. These two-lane roads provide access to the landside parking areas through a secured gate. Vehicles that use these roads include trucks transporting bypass ULDs or loose freight as well as emergency and delivery vehicles. Figure 4-10 shows an example service road between two cargo buildings on the FedEx cargo ramp at Dulles International Airport. 4.4 Landside Cargo Facility Planning Landside air cargo facilities include cargo buildings (warehouses), truck parking and maneu- vering lots, and automobile parking lots for employees and customers. Integrators, passenger airlines, and all-cargo carriers have multiple operating models within the landside facilities. This section identifies the types of carriers operating within the landside area, the throughput implications of each carrier, and the types of cargo buildings serving these carriers and their respective design attributes. 4.4.1 Utilizing Facility Planning Metrics for Cargo Building Design As indicated in the cargo apron discussion in Section 4.3.5, facility utilization data was based on analysis of 31 air cargo facility surveys for apron area, warehouse space, GSE storage, and Source: Google Earth Pro, CDM Smith analysis. Tail stand lane Service road between warehouses Cargo warehouse Fixed cargo aircraft side door loader Figure 4-10. Roads between cargo buildings and apron configuration.

Planning Considerations and Metrics 51 truck/auto parking. Airports were analyzed in this study to estimate the annual ton per square footage utilization of air cargo for warehouses. This section provides a facility requirements data matrix of ratios for the following cargo facilities based on cargo operator type, which include: • Integrated express carriers, • Passenger airlines, and • Third-party providers/all-cargo carriers. It is important to point out that these ratios are generic in nature to provide high-level guid- ance for air cargo area facility planning and are not typically applicable to individual carrier practices, which will likely have substantial variations in space requirements. These ratios, how- ever, provide capacity requirements for air cargo activity at an airport. Carrier-specific utiliza- tion data should be obtained during the inventory process. 4.4.1.1 Cargo Building Throughput Analysis Air cargo arrives via truck to the cargo building landside in one of two forms: as loose, bulky cargo, including cargo bundled on wooden pallets, or as containerized, loaded ULDs and cookie sheet pallets. Cargo building throughput rates are the standard measures to define the capacity of freight facilities, and these rates are expressed in annual tons of freight per square feet of cargo building. Airport master plans can use several other methods for determining warehouse space. Air cargo throughput rates can include the number of ULDs arriving per year, annual bulk tons per year, annual tons per ULD storage position, storage positions per elevated transfer vehicle (ETV), and annual tons per truck dock. For the purposes of this framework, the suggested throughput ratios are expressed in annual tons of freight per square feet of cargo building. 4.4.1.2 Integrated Express Cargo Building Integrated express carriers operate at most airports and have air cargo buildings with truck dock doors and an aircraft parking apron. However, one integrated express carrier commonly has a larger sortation facility on airport, and another maintains a much smaller cargo building and trucks air cargo off airport to a regional sortation facility. While these produce substantial variances in the amount of air cargo facility space required at an airport, both commonly have aircraft parking aprons at an airport if the airport does not provide a non-exclusive aircraft apron for loading and unloading of air cargo. When planning for the amount of land required to accommodate a certain volume of air cargo at an airport, airport planners would be well advised to assume that both of the major integrated express carriers would eventually need air cargo facilities that include larger cargo buildings, aircraft parking aprons, and truck circulation space and set aside ample land to accommodate a complete on-airport air cargo facility. Based on the survey data, air cargo buildings for integrated express carriers at domestic airports average 29,100 ft2 and at international gateway airports average 81,200 ft2, and aircraft apron averaged 138,000 ft2 at domestic airports and 305,000 ft2 at international airports. GSE support space for integrated express carriers averaged 79,000 ft2 at domestic airports and 171,000 ft2 at international gateway airports. This analysis provides airport planners ratios for determining space requirements metrics for the integrators. These suggested ratios are based on survey data from an extensive data collection effort. As presented in Table 4-12, cargo building space utilization based on annual cargo tonnage throughput is approximately 0.92 annual tons per square foot for domestic cargo for integrated express carriers and 0.37 for the same carrier type at international gateway airports.

52 Guidebook for Air Cargo Facility Planning and Development 4.4.1.3 Ground Handling Companies/All-Cargo Carriers As presented in the previous sections, ground handling companies operate at both interna- tional gateway airports and domestic airports. Due to the similar operating nature of ground handling companies and all-cargo carriers at airports, this analysis combines the requirements of each into one category. 4.4.2 Applying the Air Cargo Building Ratios As for the apron ratios, the air cargo facility requirements ratio matrix provides the metrics for converting annual cargo tonnage flows into cargo building requirements. Simplified calcula- tions based on empirical data from this study’s research assist in providing a range of air cargo building requirements in a preliminary design stage (see Table 4-12). The size of the cargo build- ing required (in ft2) for the typical cargo volume can be calculated by dividing the annual cargo volume by the appropriate ratio (in tons per ft2) found in Table 4-12. A representative value for an integrated express domestic O&D station cargo building is 0.92 U.S. tons/ft2 per year. For example, if an airport had an integrated air express tenant moving 80,000 U.S. tons annually, it would require approximately 87,000 ft2 of floor space (80,000 tons divided by 0.92 ft2/ton). For the same amount of cargo volume at an integrated express international gateway, 216,000 ft2 of cargo building space would be needed because it has a lower efficiency, as reflected in its smaller ratio. When applying the passenger airline ratio of 0.64 ton/ft2, the amount of cargo building space required to handle 80,000 annual tons indicates a less efficient use of space for domestic cargo. (The average tons/ft2 ratio was obtained from master plans analyzed in the literature review; ratios from this study’s survey effort were too low for facility forecasts.) Third-party handlers and all-cargo carriers would need nearly 100,000 ft2 of space to accommodate the same amount of annual volume. This methodology can be applied to current conditions at the airport as well as forecasted air cargo tonnage. 4.4.3 Cargo Building Occupants and Activity When considering the entire universe of air cargo within the United States, one finds the majority of tonnage concentrated at cargo hubs and gateway airports rather than being equally spread across the entire U.S. airport network. In fact, analysis of ACI-NA cargo tonnage data Cargo Building Annual Tons/Ft2 Required Tonnage Ratio (ft2) Integrated Express Carriers Domestic building (warehouse) 80,000 / 0.92 = 86,957 Int’l gateway building (warehouse) 80,000 / 0.37 = 216,000 Passenger Airlines Domestic building (warehouse) 80,000 / 0.64 = 125,467 Int’l gateway building (warehouse) 80,000 / 0.64 = 125,467 Third-Party Providers and All-Cargo Carriers Domestic building (warehouse) 80,000 / 0.81 = 98,400 Int’l gateway building (warehouse) 80,000 / 0.81 = 98,400 Source: CDM Smith. Table 4-12. Air cargo facility requirements ratio application: cargo building.

Planning Considerations and Metrics 53 indicates that the total cargo tonnage of the top 20 airports in the United States makes up 80% of all cargo enplaned and deplaned at the top 150 airports. The primary drivers for these large volumes of cargo at these top 20 airports are integrated express hubs (making up seven of the 20) and the global trade reflected in large volumes of imports and exports. These international gate- way and hub airports must be able to accommodate a large amount of cargo in a relatively short period of time. Cargo buildings then are not really warehouses at all but are terminals, similar to passenger terminals, with capabilities to handle rapid change and flux and dramatic variations in hourly demand. The cargo terminal serves four principal functions: • Conversion (break down and buildup of cargo pallets and ULDs), • Sorting (arranging ULDs and cargo by airline, destination, and flights), • Storage (on a short-term basis), and • Facilitation (customs, etc.) and documentation. Typical air cargo handling methods range from being manual and labor intensive to highly automated, and depend largely on the volume and speed of cargo handling required at the airport. The air cargo marketplace offers a wide variety of systems, ranging from fairly basic to technically sophisticated. Each has its place, form, and function. As illustrated in Figure 4-11, the type of handling system used is dependent to a large degree on the amount of cargo being handled and the speed at which it is being processed. Most landside air cargo terminal systems are simply dock doors to allow surface transportation (mostly trucks) to deliver goods to the building. However, not all surface cargo goes through build- ings. Many shipments are built up (prepared to be placed in the aircraft, either inside containers/ ULDs or as break-bulk) and delivered through the airport’s airside security gates, which allow trucking directly to the aircraft ramp, bypassing the cargo building, where they are loaded onto the aircraft. However, most shipments arrive through typical dock doors located along the landside of the cargo buildings. Again, some cargo has already been prepared off-site for shipment, while other cargo must be built up on-site inside the cargo building. Source: Lynxs Group. Throughput Velocity Vo lu m e Figure 4-11. Determining appropriate handling systems.

54 Guidebook for Air Cargo Facility Planning and Development For purposes of this research, airports in the United States are divided into two categories: domestic O&D airports and international gateways. This analysis does not take into consideration the express carrier hubs. Integrated express hubs are highly specialized facilities designed to move large cargo volumes in a short span of time. Integrated express hubs are typically planned and developed by the carrier’s own industrial engineers or their hired engineering consultants. Hub development in the United States is considered fully developed, and no new hubs are anticipated to be constructed in the next decade, and likely not in the next two decades. It is worthwhile to note that there are several integrator hub facilities in the Ohio Valley that have been vacated and will likely never be used again as air cargo hubs. (The U.S. integrator hub and regional hub sys- tems are fully developed for the near- to medium-term, at least. FedEx and UPS have adequate spacing and capacity in their current networks.) 4.4.3.1 International Gateways The gateway functions as a consolidation, distribution, and processing point for international air cargo. Gateway airports typically have substantial passenger airline activity, with wide-body aircraft capable of accommodating large volumes of air cargo in the belly-hold compartments. Based on historic trends, gateway airports are the airports best positioned to experience growth in international cargo traffic. To a certain extent, an international air cargo gateway is similar to a hub airport in that the gateway airport is not reliant on the surrounding market area to gener- ate sufficient cargo to justify air cargo–related operations. As with the air cargo hub, much of the cargo moving through a gateway airport does not originate and is not destined for the gateway airport’s surrounding market area. Airports in the United States that are considered international gateway airports include those in Miami, New York (JFK), Los Angeles, and Chicago. Evolving gateway airports include those in Atlanta, Dallas, and Houston. Detroit International Airport functions as a gateway to a lesser degree since the airport accommodates Delta international flights to Asia and Europe. 4.4.3.2 Domestic O&D/Local Market Stations The criteria for a local market station (a term developed for this research to identify the spoke facilities serviced by the hubs) or direct air cargo service (O&D service to an airport’s surround- ing market area) generally coincide with population centers where there is a concentration of industry, commerce, and transportation infrastructure. Often referred to as a “node” within a cargo carrier’s network, the local market station is the simplest and most common type of air cargo facility. For airport-to-airport service providers, the local market station represents the origin or destination point for the cargo they are transporting. The sole function of a direct air cargo service facility is to collect from a customer’s outbound air cargo and distribute the customer’s inbound air cargo to the airport’s surrounding market area. In order to make direct air cargo service economically feasible, the airport’s surrounding market area, or catchment area, must generate enough inbound and outbound cargo and rev- enue to offset the carrier’s aircraft operational costs. If the carrier cannot meet the aircraft opera- tional costs, the cargo is trucked to the hub or another local market station, where it is loaded onto an aircraft. Trucking to an airport outside the market area is detrimental to the carrier’s service delivery and pickup times. Air cargo terminals or cargo buildings are either occupied by a single tenant or by several tenants. 4.4.3.3 Single-Tenant Facility This warehouse type is an air cargo building/warehouse with one occupant occupying the entire facility. At most airports, single-tenant warehouses are not the predominant facility. For domestic air cargo facilities, single-tenant facilities are almost always occupied by an integrator. At international gateways, single-tenant facilities may be occupied by an all-cargo carrier and

Planning Considerations and Metrics 55 a third-party handler. There are also instances where the single tenant at gateway airports is a combi carrier (passenger airline with a dedicated freighter fleet). 4.4.3.4 Multi-Tenant Facility This warehouse type is an air cargo building/warehouse with several occupants occupying assigned areas. Tenants may be solely air cargo businesses and carriers or may be a mix of carriers and supporting businesses. Some may have no relationship with the air cargo industry but may only provide services to the passenger carriers. 4.4.4 Cargo Handling and Building Design Considerations A ULD (see Figure 4-12) is a container or a pallet that is loaded onto the aircraft and unloaded at its destination. Containers are aluminum, Plexiglas, or Fiberglass boxes that are shaped to fit the contoured sides of an aircraft. Pallets are solid wood, metal, or plastic transport structures on which shipments are stacked and wrapped in plastic and netting. The advantages of pallets over containers are that pallets are lower in tare weight, cheaper to own/repair, easier to handle, and can be stacked empty. The main advantages of containers are that they are fully enclosed, protecting their contents from the elements and theft. A disadvantage of both is that they are easy to damage. ULD loads can be assembled at the airport or arrive pre-assembled. Wide-body aircraft have rollers on both the main and lower decks, while narrow-body aircraft have rollers strictly on the main deck. The lower decks of these aircraft are bulk loaded or loaded manually. Specialized ground handling equipment lifts containers and pallets to the main deck. Containers and pallets are typically loaded and unloaded in a warehouse that may be located at an airport. Containerizing or palletizing air cargo allows for quick and efficient loading and unloading of aircraft as well as trucks. In addition, some warehouses have roller-deck flooring, which allows for movement of pallets and containers without the need for forklifts, dollies, or tugs. Igloos are similar to ULDs but are designed and contoured to load onto the main deck of a passenger airline equipped to accommodate both passengers and igloos. Approximately 50% of international air cargo travels in the baggage compartment, or lower deck, of passenger aircraft; this cargo is also referred to as “belly cargo.” The wide-body aircraft that typically serve these routes offer substantial freight capacity in lower-deck containers. Narrow-body jet aircraft, such as freighter versions of the Boeing 757, Boeing 737, and McDonnell Douglas DC9, are typically used for short-haul domestic routes, while feeder aircraft serve small market needs. Narrow-body aircraft payloads range from 18,000 to 95,000 pounds. (i) Upper Deck Container (ii) Lower Deck Container (iii) Upper Deck Pallet Source: (i) and (ii) CDM Smith; (iii) Rickenbacker International Airport. Figure 4-12. Examples of ULDs.

56 Guidebook for Air Cargo Facility Planning and Development Feeder aircraft payloads can range from 2,000 to 10,000 pounds. Upper decks on narrow-body aircraft accommodate containers, while the lower deck is bulk loaded in a process where indi- vidual pieces of freight are placed directly into the aircraft without the benefit of containers. Feeder aircraft are typically bulk loaded only. 4.4.5 Cargo Handling Systems and Storage Air cargo (mail and freight) typically arrives on the landside of an air cargo building in two forms: containerized on air cargo pallets and ULD containers and in bulk, which is loose parcels and packages that require sorting and batching prior to loading onto air cargo pallets or being packed into ULDs. Additionally, some air cargo parcels, boxes, and packages may arrive on wooden pallets, which require forklift transfers into ULDs or air cargo pallets. Cargo arriving on the landside is unloaded from trucks, typically via a truck loading dock. Typical storage methods are conventional-pallet single-deep racks, double-deep racks (allow- ing for two pallets to be inserted into a slot), drive-through racks (can be entered from either end), cantilever racks, pallet staking frames, and gravity-flow racks. Similarly, typical equipment in an air cargo building includes forklift vehicles, narrow-aisle trucks, transfer devices, elevating transfer devices, and storage-retrieval machines. The amount and type of equipment depend primarily on the type of carrier or operator using the space. In a terminal dedicated to integrated express parcel processing, the operations (mainly sorting) may be performed at ground level as well as using an elevated conveyor and slide system. Arriving air cargo is handled with a number of methods depending on the level of warehouse automation, but four categories of cargo build- ing emerge as the most common types: • Manual-load facilities • Moderately mechanized sort and load • Automated terminals and gateways • Regional integrator sort-and-load facilities 4.4.5.1 Manual-Load Facilities These are often, but not necessarily, low-volume terminals. Where manpower is available and inexpensive, freight may be moved by hand and forklifts. Extensive layouts of roller beds and transfer tables may be used. Racks may be used to store lose cargo but not ULDs. Such terminals are also desirable when there are limited funds to purchase equipment and where the operator lacks skilled labor for equipment maintenance (see Figure 4-13). 4.4.5.2 Moderately Mechanized Sort and Load ULD containers are moved by extensive layouts of roller beds, mobile lifting, and transfer equipment, such as forklift trucks. Conveyor systems and sortation platforms and slides may make up the integrated express terminal interiors. ULDs may be stored on racks. These open, mechanized terminals are suitable for medium freight flows but have two major disadvantages: they are space intensive, and the forklift operations incur high levels of ULD container damage (Figure 4-14). 4.4.5.3 Automated Terminals and Gateways Involving transfer vehicles and ETVs, these heavily automated facilities use single- or multiple- level storage of containers, which are moved within the terminal mainly by railed transfer vehicles. ETV operations produce high throughputs per square foot, with minimum container damage and reduced labor requirements. These facilities are expensive to construct and operate and require a steady stream of demand for return on investment. The advantages of this system include the

Planning Considerations and Metrics 57 savings in the number of workers and floor area, the potential for the maximum utilization of cargo terminal space, the minimization of accidents, enhanced security of the air cargo, and the minimiza- tion of damage to cargo and ULDs (see Figure 4-15). 4.4.5.4 Regional Integrator Sort-and-Load Facilities Conveyor systems and sortation platforms and slides may make up the integrated express ter- minal interiors. Containers are moved by mobile lifting and transfer equipment—for example, forklift trucks. ULDs may be stored on racks and moved on ball decks (see Figure 4-16). Source: CDM Smith. Figure 4-13. Manual-load facility. Source: CDM Smith. Figure 4-14. Moderately mechanized sort-and-load example.

58 Guidebook for Air Cargo Facility Planning and Development 4.4.6 Cargo Handling Systems The cargo storage system (CSS) is used for storing ULDs. Each cargo compartment can be designed for holding one or multiple standard IATA ULDs or pallets. Each compartment is provided with a roller deck on which the ULD moves. In the case of multiple ULDs stored in one compartment, the system ensures that they do not collide. Two types of roller deck normally installed in the storage rack are powerless storage roller decks and motor-driven roller decks. The powerless storage roller deck is driven by the ETV/stacker friction drive, which moves the ULD in or out of the storage deck. The ULDs are pushed onto or retrieved from the roller conveyor by these devices. Motor-driven roller decks are used on both the airside and landside, together with ETVs/stackers. An ETV lifts and carries aircraft ULD containers between the floor-level working and transfer environment and storage positions in the CSS structure. ETVs work best in warehouses where the cargo arrives off trucks pre-packed in ULDs or on cookie sheet pallets. Source: Lynxs Group. Figure 4-15. Automated terminal facilities. Source: Lynxs Group. Figure 4-16. Regional integrator sort-and-load facility (FedEx Express sorting system).

Planning Considerations and Metrics 59 Transfer vehicles and transfer shuttles are the traditional rail-mounted prime movers within the floor-level ULD storage and transfer systems of large airport cargo terminals. Transfer vehicles are operated by an onboard driver, while transfer shuttles are driven remotely by an operator or automated control system. Ball decks provide a multi-directional transfer medium to allow staff to manually maneuver, redirect, and reorient ULDs. Small deck areas may be installed as junctions between conveyors and other equipment, while in more extensive installations, large ball decks act as the prime mover and are used to manually transfer and manipulate ULDs between an array of interfacing equipment. Castor decks provide a high-performance alternative suitable for lighter-weight ULDs typical of express operations. Castor decks fully encapsulate the castors with treaded walkway plates, providing a safe surface on which staff can manipulate the containers. Nose-dock loading systems (see Figure 4-17) allow nose-loading aircraft (e.g., B747) to load directly from the ETV system (see Figure 4-18) through the open nose of the aircraft, which is parked immediately adjacent to the system within the cargo terminal building. Cargo terminal buildings supporting CSS vertical storage systems have ceiling heights up to 40 ft high, depending on roof trusses and fire sprinkler systems. Cargo terminal warehouses for airports supporting largely domestic cargo activity typically have ceiling heights ranging from 20 to 23 ft in height. Building heights need to be taken into consideration by airport planners since higher structures typically need to be set further back from runways to avoid penetrating the airport’s controlled airspace. Source: Boeing 2012. Figure 4-17. Nose-dock loading system.

60 Guidebook for Air Cargo Facility Planning and Development 4.4.7 Cargo Building Height Air cargo buildings in the past were often merely concrete pads with a roof and walls to func- tion as cargo consolidation and sorting stations for passenger airlines. The early cargo buildings were often refitted aircraft maintenance hangars located on a remote part of the airport. Trans- porting the cargo within the building from the storage area to the processing area and truck doors was often inefficient and space intensive. Placing the cargo on racks improved the efficiency, but tug times to the aircraft did not improve due to the remote location. First-generation cargo- exclusive buildings were low-rise structures with lower productivity per square foot since racking cargo vertically was limited. These buildings were placed closer to the terminal but were limited in footprint, and the number of truck doors was limited when compared to today’s standards. The international passenger gateway airports were often land-constrained, and space for air cargo terminals came at a high cost. Airport planners and industrial engineers had no choice but to design and build taller air cargo buildings in order to fit them on a limited land envelope. Today, at the largest international gateway airports, air cargo facilities may have up to 40-ft ceil- ing heights with multiple levels of build and break space as well ULD and pallet storage. These facility’s operators use information technology systems to anticipate loads based on bookings, airline schedules, and truck delivery schedules. These modern facilities are designed for specific airlines or third-party handlers with a particular profile in commodity types; operating equip- ment and schedules thereby increase facility efficiency. If these facilities are vacated, however, it is often difficult to find a replacement tenant that requires identical industrial designs. Retrofit- ting these facilities can come at a great expense to the facility owner. The maximum storage height depends on the cargo handling and ETV equipment capabili- ties, the quality of floor leveling (which can affect racks and ETV installation), and the storage policy of the terminal. (Priority cargo is stored at low levels for faster access.) In multi-rack stor- age systems, pallets are placed into fixed-dimension slots, and the typical height of a commod- ity pallet plus a height margin multiplied by the number of rack levels leads to the total height requirements in the warehouse area. When this height is already determined (e.g., in the reengi- neering of an existing air cargo facility), a similar calculation will provide the maximum number of levels in the multi-rack storage system. A typical height dimension for an automated-terminal Source: CDM Smith. Figure 4-18. ETV system being installed at Centurion air cargo facility.

Planning Considerations and Metrics 61 warehouse is 35 ft, but the planner should take into account the specifications for the minimum distance between the fire sprinklers systems, skylights, and roof trusses. Airports that are land rich have the advantage of not necessarily having to build tall air cargo facilities since there is typically ample space for building horizontally. These facilities may require vertical space for storage racks but may only need ceiling heights of 20 to 25 ft. The manual-load facilities and the moderately mechanized sort-and-load facilities typically can function in these lower ceiling facilities, while the automated terminals and gateways typically require greater ceiling heights. An additional advantage of warehouses with higher vertical capabilities is that office space can be accommodated on a mezzanine if the warehouse is equipped with one. Mezzanines provide cargo or equipment storage below and office space above. Airport planners need to be aware that Americans with Disabilities Act (ADA) guidelines and requirements may apply to mezzanine installation. 4.4.8 Truck Parking and Maneuvering Space Considerations The landside portion of an air cargo facility must have sufficient space for truck operations. While trucking companies make up the surface component of air cargo operations, they rarely lease space at an airport, yet airport planners must ensure that air cargo buildings where integra- tors, all-cargo carriers, and third-party handlers lease space be designed to accommodate trucking, including frontage, access, and roadway geometry. In many airports, older cargo facilities were designed to accommodate smaller 40-ft-long trucks but not today’s larger trucks (up to 75 ft) typi- cally used for long-haul trucking. Another critical element of landside planning are the employee and customer automobile parking requirements for the air cargo facility. Ideally, both must have close-in parking that is physically separated from the trucking operations, but often it is not. In instances where auto- mobile parking is limited, employee parking is usually shifted to a remote lot. Most air freight facilities have to interact with trucks for pickups and deliveries. The place this occurs is the loading bay, which by definition is the area where goods are loaded onto and unloaded from vehicles and where the freight facility interacts with the outside world. Loading bays have the following physical features: • At the truck-building interface are loading docks. Loading docks lead directly to staging areas inside the facility and, in taller warehouses, to ETV systems. • Outside the warehouse building are berths, parking pads, parking aprons, parking area, and sometimes gates. The loading dock is the crucial element that bridges the building and the truck. What should loading docks look like and how should they function? According to the Whole Building Design Guide (a web-based information base providing comprehensive guidance on building design and has been developed collaboratively by federal agencies, private-sector companies, non-profit organi- zations and educational institutions), an information resource established by the National Institute of Building Sciences, loading docks should have the following design features (Greenbaum 2011): • Location: Away from the main entrance and away from pedestrian traffic for safety reasons. • Height: Typical loading docks are platforms built 55 in. high in order to accommodate most trucks. If the height of incoming vehicles’ truck beds varies by more than 18 in., at least one berth should have a dock leveler to adjust the height. Furthermore, there should be a ramp of 1:12 grade from the loading dock to the parking area in order to facilitate unloading from the parking lot.

62 Guidebook for Air Cargo Facility Planning and Development • Depth: They should be deep enough for forklifts and other loading and unloading equipment, for rough sort, and should be easy to pull forward into the facility. [For distribution centers, the modern standard is depths of 100 feet (KOM International 2010)]. • Doors should be of the overhead coiling type, and a small personnel door should be provided. Within the facility, staging areas need to be big enough to keep the dock clear while goods are readied for movement deeper into the building. In multi-story structures, they should be adja- cent to freight elevators, which themselves must be large enough to accommodate bulky items. The property outside the building allows the truck to enter from the street, wait for entry to the loading dock, and maneuver in and out of the dock amidst other vehicles. For operations using drop trailers, there needs to be space sufficient to park a loaded trailer and to collect an empty trailer from an inventory in the yard. The outside components are berths, trucking park- ing, landing strips, aprons, and gates. • Berths are where the truck pulls in. Loading docks typically are divided into individual dock doors, with the berth serving as the entry point. Given a width of tractor-trailers at parking pads of 102 in. (8 ft 6 in.), the width of berths should be at least 12 ft, and 18 ft is recommended. • Parking pads are the concrete parking areas adjacent to the loading docks, sized to meet the needs of the largest trucks. • Parking aprons are the maneuvering area for trucks to get in and out of berths and parking spaces. • Parking area: The rule of thumb is that the number of truck parking spaces should be equal to the maximum number of trucks loading and unloading at any time (Tompkins and Smith 1998). In the majority of situations where trucks are actively engaged in transferring freight, parking space is used for queuing and holding and not for down time; in the absence of a load- ing dock, parking serves as a berth. Additional space is needed if trailers are being dropped, both to hold the loaded vehicle and to replace it from a supply of empties; aprons must be able to accommodate this activity as well. • Gates are security features typical of higher-volume operations such as those at large air cargo hubs and international gateways, or are used for valuable goods needing protection. Because trucks will queue as they enter and exit gates, approach areas or driveways should exist to allow this. 4.4.9 Truck Traffic At the larger international gateway airports where the airlines and integrated express carriers have large air cargo facilities that drive a substantial amount of truck traffic, and even at domestic airports where the integrated express carriers have substantial truck traffic, air cargo facilities are best positioned in an area that has direct access to major roadways or freeways as well as the airside taxiway system. If at all possible, airports do not want air cargo trucks comingled with vehicles going to or coming from the airport passenger terminals. For example, at George Bush Intercontinental Airport, international freighter operations are located on the opposite side of the airport from passenger terminals and have direct access to the Houston freeway system. 4.4.9.1 Cross-Docking In some cases, air cargo may be cross-docked to transfer inbound air cargo at one airport to an outbound truck destined for another airport. For example, an airline in a large market with multiple airports to choose from may use one major gateway airport as a drop station for another major gateway airport. Reasons for this could be that the airline does not have dedicated freighter/main deck service at one airport but does have it at another, or one airport has a strong market but that airline does not have the uplift capacity at that airport but has it at another air- port. This cargo would not typically be reported to the airport by an airline as enplaned cargo,

Planning Considerations and Metrics 63 and therefore, the airport will likely not know exactly how much cargo was being handled in that facility. These type of operations may be significant at some airports, and one study at JFK International Airport estimated that 25% of cargo volumes within an air cargo building may be cross-dock related. This would significantly affect an airport’s ability to plan future facilities and capacity since simply adding up tonnage from the airlines that use a facility may not always lead to an accurate portrayal of actual usage. In fact, a facility may not appear to be operationally full when the reported enplaned and deplaned volumes are reviewed, yet it may be operating above throughput capacity without an airport being aware of the constraint. 4.4.9.2 Warehouse Bypass It is not uncommon for air cargo buildings and aircraft parking aprons to be supported by a vehicle pass-through road adjacent to air cargo terminal warehouses. These two-lane roads pro- vide access from the ramp to the landside parking areas through a secured gate. Some carriers load ULDs at off-airport warehouses, then truck them to the airport. Some airports, however, do not allow trucks to pass through the security gates directly to the apron where aircraft are loaded. As a result, some carriers have installed special docks for trucks to unload ULDs and bypass the main warehouse staging area. This facility design expedites the ULD container unload without the need for the truck to drive onto the air cargo ramp area. Figure 4-19 shows an example bypass dock at Austin Bergstrom International Airport. Figure 4-19. ULD bypass dock at Austin Bergstrom International Airport. Source: CDM Smith.