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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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Suggested Citation:"Chapter 5 - Case Examples." National Academies of Sciences, Engineering, and Medicine. 2019. Airport Surface Weather Observation Options for General Aviation Airports. Washington, DC: The National Academies Press. doi: 10.17226/25670.
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52 Case Example 1: Pocono Mountains Municipal Airport (KMPO), Tobyhanna, PA The Pocono Mountains Municipal Airport is owned and operated by the Pocono Mountains Municipal Airport Authority. The airport had an existing ASOS system located at the northeast intersection of Runways 5-23 and 13-31. The ASOS, shown in Figure 11, was correctly sited and located outside of all protected surfaces. In 2011, an adjacent industrial developer had a need to expand an existing stormwater detention basin onto airport property to accommodate pro- posed offsite development. The expansion would move the edge of the basin to within 100 feet of the ASOS. An FAA Form 7460, Notice of Proposed Construction or Alteration, was filed, and the deter- mination indicated that the presence of potential standing water in the basin could create an adverse effect on the ASOS readings for temperature, dew point, and visibility. The determina- tion required either a redesign of the basin to maintain a 400-foot clearance from the ASOS or a relocation of the ASOS. In the event of a relocation, the determination noted that a Reimbursable Agreement would be required with the FAA. The authority elected to allow the basin to be constructed as planned, and in exchange received a sum of money in escrow to fund a future relocation of the ASOS. The basin was completed in 2013. In 2014, the authority began the process of relocating the ASOS. A Reimbursable Agree- ment with the FAA with a face value of $55,850.20 was executed in March 2015. The Reimburs- able Agreement allowed for limited design review services by the FAA to ensure the relocation design complied with applicable guidance. The authority was subject to certain financial limits on procurement, and as a result had to competitively bid the relocation. A contractor would construct the new site work, including elec- trical infrastructure, gravel access road, and all equipment foundations. No obstruction removal was required for the site. The NWS and the FAA would relocate the existing equipment to the new site once it was built. The design required local township design review and permitting, as well as the preparation of a Categorical Exclusion to meet National Environmental Policy Act (NEPA) requirements. Design coordination and FAA design review occurred throughout the fall and winter of 2015/2016. The project was bid in the summer of 2016. Construction of the relocated site work was com- pleted in December 2016. The total cost of the permitting, design, bidding, and construction was $139,000. The NWS completed the equipment relocation in December 2017, nearly a year after the site work was completed. The Reimbursable Agreement was closed in August 2018, at a final cost of $35,150, bringing the total project cost to $174,150. This exceeded the amount of the escrow by approximately $100,000. It is fortunate that there was enough land that met the siting requirements and did not require any clearing or grading. C H A P T E R 5 Case Examples

Case Examples 53 The timeline of this project spanned approximately 42 months from the signing of the Reimbursable Agreement in the late winter of 2015 to its closeout in the summer of 2018. This is considerably longer than what might have been expected for the relocation of existing equip- ment. However, work requiring Reimbursable Agreements will always take extra coordination time and effort. In addition, there was extensive coordination between the FAA and the NWS that required many schedules to align, which they often did not, resulting in lengthy periods of project inaction. The final cost of the relocation greatly exceeded the original estimates that generated the escrow amount. The formulation of that escrow value may not have accurately accounted for the effort required to successfully relocate the system. The Pocono Mountains Municipal Airport exists in an often-harsh wintertime environment, so the ASOS is an extremely valuable asset for aviation safety. In addition, the airport’s main operator is a Part 135 air charter service that relies on the ASOS for legal operations. Maintaining the ASOS was a necessity for the airport, despite the steep cost. Case Example 2: Seminole Regional Airport (KSRE), Seminole, OK The Seminole Regional Airport is owned and operated by the city of Seminole. The airport had an existing AWOS III P/T that was installed in the late 1990s. Over the ensuing 15+ years, the system became more difficult to maintain, with parts availability and cost becoming prob- lematic. In addition, the electrical infrastructure that supported the AWOS was old, resulting in increasing system downtime. The airport lies in an area known for extreme thunderstorm and tornado activity. The airport received a fiscal year 2016 AIP grant to install a replacement AWOS III P/T (see Figure 12). The AIP grant paid 90% of the project’s costs, with the city paying the remaining 10%. The use of AIP funding required the new system to pass a BCA per FAA Order 5100.38D, which it did. Furthermore, the work required an environmental Categorical Exclusion to meet NEPA requirements. The new system would be nominally at the same location as the existing system but would require new foundations for the all-new equipment, including a new wind tower. A new power infrastructure was installed, consisting of approximately 1,200 feet of cable distance, from the terminal building, below Runway 16-34, to the new site. The project was publicly bid, so the owner could not specify exactly what system it wanted, only that it be a certified AWOS III P/T capable of reporting to the WMSCR. This narrowed the selection of equipment to either AWI or Vaisala, as those were the only two certified systems at Source: Delta Airport Consultants, Inc. Figure 11. ASOS site work at Pocono Mountains Municipal Airport, owned by the FAA and operated by the NWS.

54 Airport Surface Weather Observation Options for General Aviation Airports the time. The winning bidder elected to install an AWI system, which was not the manufacturer of the existing system, an older Vaisala model. This change in manufacturers initially caused some trepidation for the owner, who was unsure about the usability or reliability of a new system. Ultimately, the owner reported great satisfaction with the usability of the system, including its graphics and the ability to append verbal updates to the AWOS broadcast. In addition, there has been no system downtime due to power interruptions. The final construction cost was approximately $250,000. The system was commissioned by the FAA in 2017, although an oversight in the project specifications resulted in the system not reporting to the WMSCR at startup. Ultimately, additional equipment, at a cost of $1,000, was required, plus a maintenance agreement with an FAA-approved third-party provider to com- plete the uplink. This coordination also took approximately 9 months, so that by January 2018 the system was finally reporting to the WMSCR. During the commissioning process, the FAA noted that some adjacent trees needed to be removed to comply with the wind sensor siting criteria. The owner has been attempting to clear the trees to the present date, but the work is not yet complete. Some tenants have noted that the wind sensor readings from the system are at times not consistent with their experience on the field, likely a result of the trees. The owner reports the system functions as intended and with higher than expected satis- faction for ease of use. Some pilots continue to note anomalous wind reporting, and this was also an issue with the older system. The owner continues to address this issue. The use of federal funds on a grant-obligated airport did trigger some additional administrative burdens, but these were generally a minor impact to the overall project. The coordination issues related to the WMSCR were not anticipated and resulted in a significant delay in the system reporting to the NAS, as well as a minor unanticipated cost at the project conclusion. Case Example 3: Saline County Regional Airport (KSUZ), Benton, AR The Saline County Regional Airport is owned and operated by Saline County. Prior to 2013, the airport had no weather reporting equipment. The airport secured a federal fiscal year 2012 AIP grant to install an AWOS II. The AIP grant supported 90% of the project costs, with the county paying the remaining 10%. The total project cost was approximately $180,000. The installation site did not require any specialized grading or obstruction removal. The AWOS II was operational in 2013. The system was manufactured by AWI. Figure 12. AWOS III P/T, owned by the city of Seminole. Source: Delta Airport Consultants, Inc.

Case Examples 55 The airport secured a state grant in 2018 to add a ceilometer to the system. The state grant supported 90% of the approximately $40,000 cost of the equipment. With the installation of a certified ceilometer, the system was upgraded from an AWOS II to an AWOS III, and by the end of 2018 the system was reporting to the WMSCR, so its data was available nationally. (It is noted that the FAA database, at https://www.faa.gov/air_traffic/weather/asos/?airportId=KSUZ, currently lists the system as an AWOS II and does not link to the system METAR.) The airport has a Category 1 instrument landing system (ILS) to Runway 2, which was installed in 2011. The AWOS II was not co-located with the glide slope when it was installed, nor was the system relocated with the upgrade to an AWOS III. FAA Order JO 6560.20C lists co-location with the glide slope antenna as one installation option, with the other option being placement 1,000 feet to 3,000 feet from the runway end. The location of the system appears to meet the criteria for this second option. The airport reports no plans to relocate the system. It is unknown by current airport personnel what drove the decision to initially install an AWOS II instead of an AWOS III. Possibilities discussed included the need to pass a BCA or total project cost, but no firm answer could be given. The siting requirements for the two systems are identical. The push to upgrade the system was organized by the airport manager, who is an IFR-rated pilot, in response to a desire from the local pilot community for the system information to be available nationally for flight planning purposes. The Saline County Airport Commission supported the initiative. The FAA was unable to financially support the upgrade, so the project was pursued under a state grant. System reliability has generally been good. The airport manager reports minor issues with keeping lenses clean on optical equipment as well as a minor issue with a heating unit. The airport contracts out their triannual maintenance and pays approximately $2,500 per year for this service. The airport manager reports great satisfaction with the upgrade of the system from an AWOS II to an AWOS III, due to the ability to disseminate data nationally, as well as the increased safety the system provides by reporting all relevant data. This is viewed by the airport commu- nity as a very positive development for airport utility and safety. The upgrade also allows certain corporate operators to now file flight plans to the airport due to the availability of the data, which is an additional economic benefit. Case Example 4: Carroll County Regional Airport (KDMW), Westminster, MD The Carroll County Regional Airport is owned and operated by the commissioners of Carroll County. The airport has an AWOS III, which it is proposing to relocate as part of a larger airport expansion program. The approved airport layout plan depicts a proposed AWOS III relocation site that accommodates the future airport development. In 2018, the county began discussions with a private organization proposing to construct a solar farm on airport property. This project has the potential to generate revenue for the airport as well as to support local sustainability initiatives. The solar farm location is on a portion of airport property currently being leased for agricultural use, but it also lies within the proposed AWOS III relocation site. A portion of the proposed solar farm would occupy approximately 140 degrees of the 360 degree arc of the wind sensor 500-foot clearing radius for the proposed AWOS III, and the solar panels would be located within a portion of the northern octant of the visibility sensor. Impacts from solar panels on the visibility sensor are noted in Order JO 6560.2C, Section 2.4 (p. 2-2) as follows: “The sensor should be located as far as practicable from strobe lights and other modulated light sources, as well as clusters of solar panels (farms).”

56 Airport Surface Weather Observation Options for General Aviation Airports The presence of the solar panels within the wind arc and the visibility octant was discussed with the coordinator of the FAA’s Non-Federal Program for NAVAIDs and AWOS. If relocat- ing the proposed AWOS III or the solar farm is not possible, the coordinator recommended the private firm submit a Form 7460 in order for the FAA to officially evaluate the proposed impacts and determine how or whether this installation could meet the AWOS siting order. As of this report, the FAA evaluation is still under way. Although there has yet to be an FAA opinion on this project, this issue is relevant to general aviation airports for several reasons. To meet federal grant assurances, general aviation airports are often under pressure to generate revenue that makes them self-sustaining, a practice which is difficult in the general aviation realm for many but the largest operators. Furthermore, out- side agencies may see large swaths of greenspace on airports that appear ideal for solar instal- lations and that could have the multiple benefits of meeting environmental goals, supporting local industry, and generating airport revenue. Given the large land area required to support an AWOS with wind reporting, however, these and other proposed developments may present competing priorities. Requests for solar installations at airports are growing nationwide, and in 2018 the FAA issued updated guidance to reflect this: Technical Guidance for Evaluating Selected Solar Technologies on Airports (FAA 2018). Ensuring that a proposed solar installation does not impact an airport’s weather observation system is just one of many variables that must be assessed when considering a solar installation, but it could be significant. The 500-foot wind arc covers an area of 18 acres, and solar farms could impact this area. Airports looking to incorporate solar should conduct an assessment of their weather station siting surfaces and coordinate any development with their FAA Non- Federal coordinator as an early step in the process. Case Example 5: Virginia Department of Aviation In 2010 the Virginia Department of Aviation (DOAV) embarked on a program to install automated weather observation stations at all remaining airports in the state that did not already have weather stations available on the field. At the time there were 67 public-use airports in the state, and 46 of these had a certified AWOS or ASOS station on the field. The remaining 21 air- ports had a mix of uncertified systems or no weather observation at all. The state issued an RFP for engineering services to design, bid, and administer the construction of certified weather stations at the remaining airports. An engineering consultant was selected in August 2010. The DOAV would pay 100% of all project costs from design through construction. Early in the process, one airport, Grundy Municipal, was removed from the project because the airport was proposed to be relocated in the next few years. This left 20 airports, seven of which were privately owned and 13 publicly owned. The initial project scoping included an assessment of AWOS system types from AWOS A through AWOS III for each site, with the intent to assign different system levels based on cost- benefit and overall value to the airport system. However, when it was discovered that the FAA would accept only AWOS III or better connections to the NADIN, the decision was made to proceed with AWOS III systems at every airport. The DOAV required all airports to sign a grant agreement to comply with system mainte- nance for a 20-year period. At this stage, three of the privately owned airports dropped out of the program, leaving 13 publicly owned airports and four privately owned airports, for a total of 17 airports (Figure 13). The final design managed to locate the systems so that they mostly met the criteria. Given the land constraints of many of the airports, most of which were smaller GA airports, it was not

Case Examples 57 possible to locate all the systems so that they met all the siting criteria. The siting issues were resolved by first reviewing each airport with the FAA Non-Federal coordinator to identify the challenges and select locations that would be least compromised but that could still provide reliable data. This included a review of aerial photos, site photos, and survey data for the local topography. In many cases, this required locating the systems closer to the runway than the sit- ing order specifies. However, because the runway offset criteria are mostly an airspace issue, all systems had an FAA Form 7460—Notice of Proposed Construction or Alteration filed, and all systems were cleared as No Hazard before installation. The installation of additional obstruction lights was required for some systems. As part of the review process, the FAA recommend the installation of the wind sensor on a taller-than-standard tower at nine locations, with seven towers at 40 feet and two at 50 feet. The use of higher towers helped to mitigate the effects of close-in airport buildings or trees and was a cost-effective solution because available land was limited at many locations. In addition, two systems were installed as a “split system,” where the wind sensor was not co-located with the remaining equipment. This flexibility allowed for the location of the wind sensor where it could gather reliable data but where other ground conditions (localized fog, ambient lighting) could impact the other sensors. The remaining sensors were located in a com- pliant area, and the full system was linked together via data cables or UHF data transmission to the AWOS processor. Early and clear coordination with the FAA was vital to the approval of these nonstandard locations, but also to installation of systems that could still provide reliable certified data. The decision was made to bid the project in two phases, with the first phase to include system installation and minor tree removal, and the second phase to include the large-scale obstruc- tion (tree) removal at two airports. Ultimately the tree clearing at one airport was accomplished under a parallel but unaffiliated project at that airport, meaning only one site required large- scale clearing of 11 acres of trees. The design of the systems occurred through 2011 and 2012. Much of this time was spent coor- dinating FAA airspace approvals, NEPA environmental compliance for the five NPIAS airports, and local permitting and plan approval. The project also required extensive work with the coordinator for the FAA’s Non-Federal Program for NAVAIDS and AWOS in Atlanta. The Non-Federal coordinator was instrumental Source: Delta Airport Consultants, Inc. Figure 13. One of 17 AWOS III systems installed by the Virginia Department of Aviation.

58 Airport Surface Weather Observation Options for General Aviation Airports in assisting with airspace coordination, system information gathering, and facilitating the VHF frequency assignment for the new systems. This last item was challenging, because it was atypical for so many new frequencies to be assigned at once. Options were even investigated to transmit the AWOS systems over shared NAVAIDS or UNICOM at some airports, but ultimately the FCC found dedicated frequencies. The discussion of frequency congestion and interference was a serious item of concern during this phase of the project. In fact, the system installed at the Front Royal Airport (KFRR) required extensive tuning and filtering because the assigned frequency bled heavily over the CTAF. This issue took months to resolve. An additional frequency issue was the assignment of UHF frequencies for some systems. A UHF frequency is often utilized to transmit data on site from the field equipment to the pro- cessor at an airport terminal. Some facilities did not have a terminal building or could accom- plish this data transmission via hardwire connection if the distance between the locations was short. Thirteen systems required a UHF frequency, and this task could only be accomplished through an FCC-approved frequency coordinator. An approved coordinator was found, and ultimately all licenses were obtained. The system installation project was bid in the fall of 2012, and the winning bidder elected to install AWOS III systems manufactured by Vaisala, Inc. The project could not dictate the manu- facturer, only that the systems be certified by the FAA, which meant only one of two manufacturers was eligible; AWI was the other. The installation of the systems began in the spring of 2013, and by early 2014 all systems were operational. The installation contractor was responsible for coordinating the FAA com- missioning of all systems. This contractor had extensive experience installing and inspecting AWOS systems and installed all systems to the satisfaction of the FAA. The DOAV manages NADIN connections for all AWOS systems in the state, and facilitated and paid for the connec- tions for the new systems. The single-site clearing project was bid in the summer of 2013 and the tree removal was complete by the end of 2013, although site restoration was not finalized until early 2016. The average system installation cost for the 17 systems was $140,000, and the bid prices per system ranged from $115,000 to $165,000. Including the site-clearing costs for the 11 acres, the most expensive site cost rose to $265,000. These costs do not include the engineering design or administration costs or materials testing for construction. These costs are much lower than those that should be anticipated today. The contracting environment was much different in 2012 and strongly favored the owner. The Great Recession was still lingering in the construction industry, and the favorable bid prices reflected this. As an example, an AWOS III bid in 2006, during better economic times, as part of a $4 million Phase 2 bid package for a new AIP-funded general aviation airport in Virginia was bid at $197,000. The Virginia project did not include any AIP provisions. This project also presented great economy of scale for the contractor, who was located within 100 miles of most of the sites and was able to sequence the work to keep his personnel efficiently working on multiple systems at once. The geographic reach of the project covered nearly all of Virginia east of the I-81 corridor, from the Maryland border in the north to the North Carolina border in the south, and to Tangier Island in the Chesapeake Bay. All of the systems are owned by the respective airports. At the time of the project, the DOAV supported system maintenance and parts statewide at an 80% level. Subsequently, the state increased this support level to 95%, providing one of the best, if not the best, state financial sup- port systems in the country.

Case Examples 59 System benefits have not been documented in any official manner. Working under the theory that more weather reporting provides for a safer system overall, the project provided a benefit by expanding nationally available METAR coverage to many rural areas that were underserved by NAS weather reporting. This should have benefits not only to aircraft using the airports, but also to the helicopter industry, which is striving for increased density of weather reporting in many states. The DOAV was also simultaneously undertaking a project to develop instrument approaches for all airports in the state, so on-site weather would also assist by eliminating poten- tial RASS penalties. Finally, these airports will also now become accessible to certain Part 91 and Part 135 operators who require local weather reporting. Case Example 6: New Kent County Airport (KW96), Quinton, VA The New Kent County Airport is located approximately 15 miles east of Richmond, Virginia. It is a local service GA airport with a 3,600-foot runway and a GPS approach. It is located about 9 miles from the Richmond International Airport (KRIC) and is situated underneath the outer ring of Richmond’s Class C airspace. KRIC is a small-hub commercial service airport with a 9,000-foot runway and has ILS and GPS approaches. Both airports are located off Interstate 64, with only occasional summer vacation traffic slowing travel between the two. KRIC is easily accessible to KW96, with little congestion, and has readily available ground transportation from the airport to the city. The city of Richmond is supported by two other GA airports: Richmond Executive (KFCI) to the southwest and Hanover County (KOFP) to the north. Both have good access to downtown Richmond, both have runways over 5,000 feet and GPS approaches, and KFCI has an ILS approach. All four of these airports have AWOS III or better, and all report to the WMSCR. The Middle Peninsula Regional Airport (KFYJ) is located about 17 miles east of New Kent. It has a 5,000-foot runway, a GPS approach, and an AWOS III reporting to the WMSCR. Twenty years ago, KW96 traffic was generally from local enthusiasts, with some business and golf traffic mixed in. The fleet mix was almost all piston, with occasional turboprop, and very little jet traffic. Although close to the city of Richmond, KW96 is 10 miles farther from the city than KRIC. The 3,600-foot runway has a swamp on one end and a road on the other, so length- ening the runway to attract larger, higher-performance aircraft would be very costly. In the 1990s, weather advisories at KW96 consisted of a windsock and an occasional UNICOM operator. Pilots generally called by phone to get the weather from KRIC or KFYJ. The local pilots saw the lack of any type of weather advisories as the biggest challenge to using the airport, so the airport staff investigated affordable options. Neither the FAA nor the state would fund an AWOS, since there were three others within 20 miles of the airport, and this coverage was considered to be sufficient by these agencies. To meet the airport’s need for some type of weather advisory, the state agreed to fund a Belfort DigiWx system. The system was easy to install, pulling power from the windsock and transmitting wirelessly back to the processor and monitor in the terminal. Although the system was strictly advisory, it provided wind speed and direction, temperature, dew point, a ceiling estimation based on adiabatic lapse rate, and barometric pressure. The system could be accessed by phone but required a special handheld receiver to receive in the air. There was a monitor in the terminal building with a clear graphic display of the runway and wind, and text for the other

60 Airport Surface Weather Observation Options for General Aviation Airports information. It was very easy for the UNICOM operator to interpret and relay information to pilots, but they had to make sure that they included the word “advisory.” In the mid-2000s, the DOAV set a goal to have GPS approaches and AWOSs reporting at all the public-use airports in the state. In 2013 a new AWOS III was installed at KW96 (see Figure 14) as part of a larger statewide project by the DOAV, at a cost of $130,000. The DOAV paid 100% of the design and installation costs. To ensure that all the AWOS systems in the state are properly maintained and inspected, the DOAV later established a 95% funding program to support the 50+ eligible AWOS systems in the state. In addition, the DOAV pays all the NADIN access fees, so there is minimal O&M cost to the airport. The impacts of installing this upgraded weather system at the airport are difficult to quantify, and there has been no dedicated effort to do so. There are four other airports within 20 miles, all of which have at least 5,000-foot runways, GPS or ILS approaches, and good ground accessibil- ity to Richmond. KW96 still has a 3,600-foot runway without current justification to expand, and although the number of annual operations has increased, the types of operations remain largely the same. The installation of the AWOS III hasn’t opened the doors to larger, higher- performance aircraft because the runway length is still the limiting factor. The on-site weather technically provides greater utility for Part 135 and Part 91K operations, but the runway length is likely limiting for these operations, especially when considering the 60% rule and 80% rule associated with them. The primary value of establishing the initial advisory weather system at KW96 was to satisfy the needs of the local pilot community, and that advisory system largely met those needs. Invest- ing in the AWOS III certainly provided the pilot community with a more sophisticated and certi- fied level of weather observation, as well as increased access to the data on a national level, but it did not address a local need that wasn’t already met by the advisory system and the numerous certified systems surrounding the airport. Source: Delta Airport Consultants, Inc. Figure 14. AWOS III owned by New Kent County.

Case Examples 61 Case Example 7: Alaska Aviation Camera System According to the website of the Alaska Department of Statewide Aviation, Alaska has more than 400 public-use airports. With a land area exceeding the size of Texas, California, and Montana combined, Alaska relies heavily on aviation because 82% of Alaskan communities are not linked by roads. Aviation needs are met by a pilot community six times larger per capita, and an aircraft fleet 16 times larger per capita, than the rest of the country. Alaska’s geogra- phy and climate vary greatly from the national norms, with rapidly fluctuating and often harsh weather over challenging and rugged terrain. Pilots in Alaska face many operational challenges, not just from the extreme terrain and the weather. As their planes are often the only means to move people and supplies, the pilots are faced with economic pressures. Commercial operators are very often faced with not just a go/no go decision, but a go-or-someone-else-will-do-it-instead decision. So, a weather-based decision can become a weather and revenue decision. Very often, for a destination with no source of weather information, the decision has been to initiate the flight and see how far they get. These are the types of operations that are not just economically inefficient but also potentially dangerous. In 2016, the Alaska Aviation System Plan indicated that there were 160 sources for approved weather in Alaska. Unfortunately, due to the size of the state, to match the density of approved weather for the rest of the country, Alaska would need to more than double the number of weather facilities by adding another 200 approved stations. To help overcome the challenges posed by operating in such a harsh and rapidly changing weather environment, the FAA installed a network of weather observation cameras at 228 air- ports around the state. The cameras are all accessed through an FAA website (see Figure 15) that Source: https://avcams.faa.gov/. Figure 15. Screenshot of FAA website for accessing Alaska’s weather observation cameras.

62 Airport Surface Weather Observation Options for General Aviation Airports allows users to see for themselves what the current conditions are at a destination airport, and any METARs, terminal aerodrome forecasts (TAFs), and pilot reports (PIREPs). Each airport has color-coded indicators for the types of weather data available (see Figure 16). More than 900 cameras, typically offering four views per airport, are strategically aimed to give the pilot visual confirmation that the airport is accessible and that surrounding terrain is visible (see Figure 17). For each camera angle, a clear-day photo with notes about obstruction heights and distances is provided for reference (see Figure 18). The website also makes available any advisory weather that may be available (Figure 19). It is the only FAA website that was identified as part of this study that provides weather that is documented at “Advisory Weather.” Many commercial operators have made checking the website part of their operational stan- dard operating procedures because it significantly decreases the number of flights that fail to make it to their destination for weather reasons. The actual camera views do not provide certified weather observations for the pilot and are only of use during daylight hours. The FAA has labeled the camera information as “supplemen- tal.” But both the website and the cameras represent an innovative approach to helping pilots operate in an unforgiving environment and make better decisions before leaving the ground. Other states are beginning to use similar technology, but none have the robust and comprehen- sive website that the FAA has put in place in Alaska. Case Example 8: Mississippi Center for Emergency Services: Air Ambulance Operation The Mississippi Center for Emergency Services (MCES) is a department of the University of Mississippi Medical Center in Jackson, MS. One of the services provided by the MCES is air transport services for critical-care patients. The MCES owns four air ambulance helicopters, and they are operated under a Part 135 certificate maintained by PHI Air Medical, LLC. Source: https://avcams.faa.gov/. Figure 16. Screenshot of FAA web page showing color-coded indicators.

Source: https://avcams.faa.gov/. Figure 17. Screenshot of FAA web page showing four camera angles. Source: https://avcams.faa.gov/. Figure 18. Screenshot of FAA web page showing clear-day reference photo.

64 Airport Surface Weather Observation Options for General Aviation Airports The air transportation of medical patients by helicopter is colloquially referred to by many names: medevac, life-flight, air ambulance, air-care, and others. The FAA regulations for these operations utilize the term air ambulance, and that is used here. Regulation 14 CFR Subpart L, Section 135.611—IFR Operations at Locations Without Weather Reporting, specifies minimum weather reporting data needed to conduct IFR opera- tions for air ambulance operations in the event the aircraft is operating to or from an airfield not served by an NWS or FAA-certified weather reporting system. Section 135.611(a)(1) states: The certificate holder must obtain a weather report from a weather reporting facility operated by the NWS, a source approved by the NWS, or a source approved by the FAA, that is located within 15 nautical miles of the airport. If a weather report is not available, the certificate holder may obtain the area forecast from the NWS, a source approved by the NWS, or a source approved by the FAA, for information regard- ing the weather observed in the vicinity of the airport. The primary requirement conveyed in this passage is that for IFR operations, an air ambu- lance must receive certified weather data from a source within 15 nautical miles of the opera- tion. The FARs do allow for some exceptions to this; however, Section 135.617—Pre-Flight Risk Analysis also requires operators to assess the weather in totality and document why they made a go/no go decision. The assessment of risk by any one operator will vary greatly and is not the subject of this case example. Instead, the focus will be on the ability to meet the primary metric: certified weather within 15 nautical miles. By necessity, air ambulances may be called upon to operate in every weather condition and in every part of a state. The medical director for the MCES, Damon Darsey, M.D., indicates that approximately 60% of their operations are conducted from one medical facility to another, and 40% are conducted on scene. The term “on scene” does not mean the aircraft lands directly at the scene of an incident (e.g., on a highway at a traffic accident), but more commonly the helicopter will land at the nearest airport, helipad, or suitable landing site and the victim will be ground-transported to the helicopter at that location and then air-transported to an appropriate medical facility. The location of these on-scene landing facilities is variable and unpredictable, as is their prox- imity to a certified weather reporting station. This proximity is a function of how many certified weather systems are available statewide. The FAA database indicates that there are 33 ASOS or AWOS III (or higher) weather stations in Mississippi. The MCES further reports that three of these systems are currently inoperable. Each weather station supports a Part 135 coverage area of approximately 935 square miles, meaning the 33 systems cover approximately 31,000 square miles, or 63% of the state. This is a slight oversimplification, because many coverage areas over- lap or extend beyond state borders. In reality, around 50% of the state lies within 15 nautical miles of a certified weather system. Source: https://avcams.faa.gov/. Figure 19. Screenshot of FAA web page showing advisory weather data.

Case Examples 65 The medical director of the MCES indicated that in 2018 they had to deny support of approx- imately 500 transport calls due to a lack of sufficient weather information on site. (Note that this number is anecdotal and not perfectly data supported.) The MCES website also indicates that no other air ambulance program in Mississippi is certified to conduct IFR operations. The lack of certified weather stations with sufficient geographic coverage has the potential to threaten public safety in many parts of the state, especially rural areas which are the farthest from advanced medical care centers. The possible extent of these impacts is discussed in the Future Research section of this report. Mississippi has 73 public-use civil airports listed in the NPIAS, a further six public-use airports not in the NPIAS, and six military airports. The current certified weather systems are predominantly installed at these airports. However, over half of the NPIAS airports have no certified weather reporting system. These airports are eligible for federal funding for an AWOS III system, and the additional installation of these systems would broaden the cover- age access for air ambulance operations, as well as increase flight safety and overall NAS utility for all users. It is possible that the smaller NPIAS airports could not pass the required BCA for an AWOS III or could not support the installation or maintenance costs of the systems. Mississippi has a population density over 50 people per square mile and so does not meet the BCA exemption threshold included in the FAA Reauthorization Act of 2018. The ability for Mississippi’s only IFR-certified air ambulance service to support public safety is compromised by the coverage area provided by the current FAA-certified weather system network in the state. This coverage area includes approximately half of the state, which means that many (mostly rural) areas cannot be served at all, or that extended ground transport time is required in the patient transport process. This topic is discussed further in the next chapter.

Next: Chapter 6 - Conclusions and Future Research »
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The needs of airports may vary depending on the types of operations typically conducted at the airport, as well as the type of weather common to the airport.

The TRB Airport Cooperative Research Program's ACRP Syntheis 105: Airport Surface Weather Observation Options for General Aviation Airports aims to provide the operators of general aviation (GA) airports a comprehensive source of information about airport-based weather observation options so they may make informed decisions to support the specific operational needs of their airport.

Weather observations at airports can come from either FAA-approved (certified) or advisory (non-certified) sources. Weather reporting at a GA airport, whether certified or not, typically comes from automated sources, as human observers are increasingly being phased out or are stationed mainly at commercial service airports.

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