Airside Snow Removal Practices for Small Airports with Limited Budgets (2015)

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28 This section addresses NOTAMs and other condition reporting techniques, winter accident and incidents, and general operational safety. NOTICES TO AIRMEN Airport managers have a duty and responsibility to inform airport users about field conditions and hazards that exist on the airport. By establishing standard design criteria for pavement surfaces, markings, lights, signs, and other areas of airports, the FAA seeks to minimize hazard exposure and provide for a common and familiar layout for pilots operating among airports. For this reason, airport operators are required to inspect their facilities on a regular basis. Any change in the condition of the inspected items requires notification to pilots and airport users. The NOTAM system is the primary method for disseminating information to the pilot about the change in conditions at an airport. NOTAMs issued to reflect winter conditions at airports are often referred to as SNOWTAMs. For reporting special winter operational conditions such as braking actions, winter conditions, runway light obscuration, and snow bank obstructions, the airport manager can find guidance in the FAA advisory circular and the joint order on NOTAMS (AC150/5200-28D 2008; FAA Order JO 7930.2P 2014). Pertinent to the need to remove snow and ice from pavement surfaces, AC 150/5200-28D reads: For commercial service airports, the FAA requires “prompt” removal of snow. For general aviation airports, the FAA does not impose any specific responsibility on the airport to remove snow or ice other than providing a safe and usable facility. If a winter storm renders parts of the airport unsafe, the airport is only obligated to promptly issue the necessary NOTAM, and close all affected parts of the airport until the unsafe conditions are remedied. The airport should then correct unsafe conditions within a “reasonable” amount of time. The interpretation of “‘reasonable’ amount of time” is reflected in the recommended clearance times identified in Tables 7 and 8 in chapter two. Different methods can be used for issuing NOTAMs. The primary means of dissemination is to contact the privately contracted Flight Service Station (FSS), either by telephone or by submitting a digital NOTAM (d-NOTAM). A newer system for authorized airports allows for direct electronic sub- mission of information into the NOTAM database (e-NOTAM). The difference between a d-NOTAM and an e-NOTAM is primarily the level of authorization for issuing a NOTAM. With a d-NOTAM, information is conveyed to the FSS and is checked for conformance and clarification before entering the system. Under the e-NOTAM system, a trained airport operator has the authorization to enter the data directly into the system through a web-based standard menu-driven template approved for that airport (https://notams.aim.faa.gov/scert/). Other means can be used to supplement NOTAMs and ensure that a change in airport condi- tion is conveyed, as depicted in Table 27. Nearly half of the basic airports surveyed do not issue condition reports and instead rely either on a pilot to call the manager or to use Unicom frequency to request conditions. One interviewee mentioned that in his very northern state, it is common, and expected, that a pilot would call ahead to an airport to ask about conditions before conduct- ing a flight because conditions change frequently and any report made to FSS can easily become outdated. chapter four SAFETY ISSUES

29 Standard practice in the airport industry is to monitor changing airfield conditions carefully and disseminate information about those conditions in a timely manner to airport users. Runway condition reports are to be updated any time a change to the runway surface condition occurs. This presents a challenge to small airports with limited budgets, as the airport is not normally staffed 24 hours a day. For those airports that do not monitor weather conditions between certain hours owing to staffing limitations, the FAA suggests the airport issue a NOTAM and include the following text: “Airfield surface conditions are not monitored between the hours of ‘x – y’.” This additional text helps to avoid erroneous condition assessments by users of the information. Airport managers are responsible for ensuring NOTAMs are issued for their airports. If a contractor is engaged to conduct snow removal operations, provisions are necessary to ensure notices are issued properly. Illustrative of one problem is an operator who commented that while the contractors he uses were diligent in their snow removal, they were not versed in field condition reporting. This made it necessary for the airport manager or other trained airport employee to be available whenever the contractor was conducting snow removal operations. RUNWAY FRICTION MEASUREMENT The expected condition for a runway is that it is in “no worse than wet” condition, as aircraft performance tabulations are based upon such conditions. Because contaminants such as ice, snow, slush, and sand on the runway can greatly impede the performance characteristics of aircraft and cause hazardous conditions, the FAA limits aircraft operations as contamination develops on the pavement surfaces. In general, ice of any kind, accumulation of slush not exceeding one-half inch, wet snow not exceeding one inch, and dry snow not exceeding two inches are the trigger points for snow removal operations need to begin. The trigger points can be at lower thresholds for some aircraft types, which is why it is important to be familiar with the type of aircraft using an airport. Reports of braking action using measuring devices can be reported as Mu (the symbol represent- ing the coefficient of friction, or slipperiness of a paved surface), or by the descriptive terms of good, medium (fair), poor, or Nil. There is debate about the usefulness of braking action reports made to pilots, centering on the concern for variability and lack of correlation between the readings obtained and the actual braking experienced by aircraft. NOTAM-Condition Reporting Basic Local Regional Reliever NP COMM SVC Call to FSS 2 15 5 5 5 d-NOTAM — 5 1 1 2 e-NOTAM 1 10 3 1 2 Supplemental Reporting ARTCC — 1 — — — ATCT — 1 4 2 1 ATIS/AWOS — 5 2 2 1 Unicom 3 10 1 2 3 Internet — 3 2 — — Intranet — — — — — Social Media — 2 1 — — Telephone Recording — 1 — — — Verbal or Oral Delivery — 5 3 — 1 Post on Board — 1 — — 2 Pilots Call Manager 3 10 4 3 1 No Special Reports 2 — — — — Note: Many airports use multiple methods to disseminate information. — = no data. Source: SMQ Airport Services. TABLE 27 SURVEY RESULTS OF WAYS NOTAM INFORMATION IS DISSEMINATED

30 The FAA is concerned that pilots may rely on information that can be misleading when making decisions about whether they can safely operate on the runway surface. The FAA has established that the correlation of a braking action report by vehicle or measuring device to the actual braking action that a pilot will experience is not consistent (AC150/5220-30C 2008): Airport operators must not attempt to correlate friction readings (Mu numbers) to Good/Medium (Fair)/Poor or Nil runway surface conditions, as no consistent, usable correlation between Mu values and these terms has been shown to exist to the FAA’s satisfaction. It is important to note that while manufacturers of the approved friction measuring equipment may provide a table that correlates braking action to Mu values, these correlations are not supported by the FAA. To ensure that data collected are accurate, qualified personnel should use FAA- approved equipment and follow the manufacturer’s instructions for use. Further guidance on runway friction measurement may be found in AC 150/5320-12C, Measurement, Construction, and Maintenance of Skid-Resistant Airport Pavement Surfaces. Comments in the survey reflected the concerns stated in the AC about the accuracy of the deter- minations, with three airports reporting they use a vehicle to assess a runway condition only upon a pilot request. The use of friction measurement devices and the reporting of runway braking action varies among the airports. For this reason, the FAA is transitioning to a new runway condition assessment matrix (RCAM) in 2016. The RCAM will provide for a standardized method of reporting runway surface conditions. Mu values or friction readings will no longer be used. FAA Order JO7930.29 NOTAMs has been revised to reflect the new standardized terminology (FAA Order JO7930.29 2014). Although RCAM will not rely on friction measurements, the FAA views the use of friction mea- surement devices, which are eligible for AIP funding, as an aid to assist the airport operator in assessing the condition of the pavement surface over time, rather than as the actual state of pavement condition. AC 150/5220-30C specifically states: Therefore continued transmittal of Mu values is permissible with the understanding that the particular numerical value has no particular significance other than to provide changing runway condition trend information when associated with previous or subsequent runway friction measurement values. Airport operators are cautioned against using Mu values as their sole indicator of winter runway slipperiness. Additionally, note the U.S. movement to the use of the [International Civil Aviation Organization] term ‘medium’ instead of the term ‘fair.’ Until the transformation to ICAO terminology is complete, this AC will express the term as ‘medium (fair).’ It is recognized in the industry that pilots continue to seek information from airports with or without approved devices, as any report is considered an additional piece of information pilots may find use- ful to their decision-making process to operate safely. AC 150/5220-30C instructs airport operators to conduct runway friction assessments or inspections whenever necessary to determine if conditions are deteriorating. Deteriorating conditions can include: • frozen or freezing precipitation • falling air or pavement temperatures that may cause a wet runway to freeze • rising air or pavement temperatures that may cause frozen contaminants to melt • removal of abrasives previously applied to the runway as a result of wind or airplane affects • frozen contaminants blown onto the runway by wind. The FAA expects the airport operator to take reasonable steps to improve any deteriorating pave- ment condition, if he/she have the capability; or to otherwise issue a NOTAM. The FAA reports in AC 150/5200-30C that studies it has conducted indicate a pilot’s braking action report or a braking action assessment by the airport operator that results in a “nil” condition is a serious concern no matter what type of device or means made to measure the condition. The AC states: A NIL pilot braking action report (PIREP), or NIL braking action assessment by the airport operator, requires that the runway be closed before the next flight operation. The runway must remain closed until the airport operator is satisfied that the NIL condition no longer exists. . . . Under the conditions noted above, the airport operator must take all reasonable steps using all available equipment and materials that are appropriate for the condition to improve the braking action.

31 Of the airports in the survey using friction measurement devices, all identified them as being decelerometers (Table 28). It was not identified if the decelerometers were of the electronic or mechanical type. The FAA suggests in the AC that airports with mechanical decelerometers upgrade to the electronic type for better reporting capabilities. Whether or not an airport has a friction measuring device, the FAA expects the operator to con- tinuously monitor the airfield conditions and file NOTAMs as necessary. “Continuous monitoring” procedures can vary from airport to airport and can include the following: • observing which exit taxiways are being used • maintaining a regular program of friction testing to identify trends in runway traction • monitoring runway physical conditions including air and surface temperatures, contaminant types, and depths • monitoring pilot communications • monitoring weather patterns. APPLICATION OF DE-ICING, ANTI-ICING, OR OTHER AGENTS In the event of deteriorating pavement conditions, improvement may be achieved by application of treatment or by removal of contaminant. The means to prevent, improve, or correct a Nil or other braking action condition that impedes runway safety include the application of sand or chemicals to the runway surface. Because of cost, the majority of airport managers in the survey do not use any treatment method. Only 12 of the 45 airports in the survey reported using solid de-icing chemicals or sand to mitigate poor braking action. None of the surveyed airports reported the use of liquid de-icing chemicals. Sand applied to runways and taxiways are to meet specific FAA specifications, except in the state of Alaska. Ordinary sand is not acceptable. Several airport operators lacked adequate space or equipment for sand or chemical storage. Storage facilities are eligible for funding under AIP. Table 29 identifies those airports that have available, and are able to apply, friction enhancements. Five managers in the survey noted they were often hesitant to use sand because of objections by pilots using the airport (concern for sand ingestion into the engines); and because of the added cost of having to clean any sand application from the pavement surface afterwards. As one airport operator noted, sand is simply not needed if they do a good job of snow removal (i.e., brooming slush or snow off before it becomes ice). Braking Action Reporting Basic (6) Local (21) Regional (7) Reliever (6) NP COMM SVC (6) None 6 11 1 2 1 Vehicle Braking — 6 — 2 — Decelerometer — 4 6 2 5 — = no data. Source: SMQ Airport Services. TABLE 28 NUMBER OF SURVEYED AIRPORTS THAT MAKE RUNWAY FRICTION OR BRAKING ACTION REPORTS AND THE TYPE OF EQUIPMENT OR METHOD USED Apply Runway Material Basic Local Regional Reliever NP COMM SVC None Applied 6 13 4 3 4 Sand Applied — 7 2 — 3 Chemical Applied — 7 2 3 — — = no data. Source: SMQ Airport Services TABLE 29 NUMBER OF AIRPORTS THAT HAVE PAVEMENT FRICTION MATERIAL AVAILABLE

32 More than half of the surveyed airports did not have friction enhancement capabilities. Beyond the cost, environmental issues also may apply, though the majority of respondents indicated stormwater pollution prevention was not a concern at their airports. One effective means for managing icing conditions is to place an anti-icing agent on the pavement surfaces before the event to prevent the ice from forming. However, survey respondents stated anti-icing compounds are little used at their airports because of their cost, the dedicated equipment needed for spreading or dispersing the compounds, and the lack of facilities to store the material and protect it from the elements before disbursement. The use of mechanical ice removal is preferred. SNOWBANKS Safe airport operation requires that any accumulation of snow is not to interfere with aircraft propellers, landing gear, or obscure runway or taxiway lights, signs, or NAVAIDs (AC150/5200-30C 2008). This can become a challenge as snow is pushed by plows from the center or far edge of a runway to one side. The snowbanks formed can obstruct a pilot’s view of the lights and signs, or be of a hazardous height that might interfere with aircraft operation, propellers, or wings. Consistent winter storms with no melting in between add to the accumulation, possible obscuration, and difficulty of removal. Figure 11 is an example of hazardous snowbanks at the approach to a runway as a result of poor plowing technique. The standard tool described by survey respondents for removing snow banks and leaving clean edges is the snowblower (Figure 12). Two related methods are to plow snow either to the pavement edge or plow to the center of the pavement and then use the rotary snowblower to cast the accumula- tion over the lights and signs (Figure 13). FIGURE 11 Example of hazardous snowbanks at a runway approach. Photo credit: S. Quilty, SMQ Airport Services. FIGURE 12 Example of snowblower eliminating hazardous snowbanks at a runway approach. Photo credit: G. Sussey, Watertown, New York.

33 Another method is to run a plow along the pavement edge lights, pushing the snow toward and onto the adjacent pavement. This is most effectively accomplished when the ground is frozen to prevent a tire rut from forming or the vehicle becoming mired in soft ground. The berm is then cast over the lights with a blower or picked up by a loader. Survey respondents used both techniques, with the wind direction and frozen ground determining where they placed the windrow. In the absence of a blower unit, several survey respondents call in a third party (city, county, contractor) to assist them with snow bank pushback or clearing with a loader. Yet another method is to use a snowblower to clear either side of the lights or signs, provided the ground is frozen. An example is shown in Figure 14. Another method is to use a front-end loader with a bucket or blade attachment to push the snow past the lights. The last method, while not indicated as available at any of the airports surveyed, is a blade attachment that is split open to allow the light fixture to pass through. One airport developed a site plan that does not allow snow mounds in certain areas of the airport. If the accumulation gets too high in any area where mounds are not allowed, it is moved with a loader and dump truck (Figure 15). Several airports call for the PWD or a contractor to move the banks. One airport operator in the basic category stated he had no option but to issue a NOTAM for hazardous snowbanks, as his equipment did not have the capability to prevent or remove them. RUNWAY INCURSION PREVENTION A runway incursion is any occurrence at an aerodrome involving the incorrect presence of an aircraft, vehicle, or person on the protected area of a surface designated for the landing and take-off of aircraft (FAA Order 7050.1A 2010). In essence, an incursion can occur when SRE or an individual is within FIGURE 13 Example of snow having been windrowed to allow for a snowblower to remove it. Photo credit: C. Lawson, Romeoville, Illinois. FIGURE 14 Example of using a snowblower to eliminate snow accumulations around lights and signs. Photo credit: G. Sussey, Watertown, New York.

34 the runway environment and aircraft is moving to, from, or on the runway. An incursion poses a serious hazard to people and equipment. For an airport with an ATCT, vehicle movements on the runways and taxiways must be authorized by an air traffic controller whenever the tower is in operation. Preventing runway incursions at an uncontrolled airport becomes more problematic. The majority of airports for this synthesis are considered uncontrolled airports, as they do not have an ATCT (Table 30). The six airports in the survey that have an ATCT have part-time hours of operation, 7 a.m. to 11 p.m. The other 40 follow the procedures to prevent incursions outlined in the FAA’s Aeronautical Information Manual (AIM) for operations at uncontrolled airports (AIM 2014). With many snow events occurring in the late night or early morning hours, snow removal can occur when the ATCT is closed and uncontrolled procedures are to be used. Extra vigilance by equipment operators for radio communication and possible aircraft operation is necessary. Radios and NOTAMs are means of communicating with pilots about hazardous winter conditions or for ongoing SRE operations. Table 31 identifies the number of airports in the survey that had radios installed in their SRE. A combination of radios refers to several SRE having a mixture of radios that receive and transmit, or receive only. Installing runway entry signs and pavement hold line markings to prevent runway incursions are standard safety practices at many airports in the survey, as noted in Table 32. FIGURE 15 Example of a front-end loader removing snow mounds. Photo credit: R. Lanham, Auburn, Maine. Air Traffic Control Tower Operation Basic Local Regional Reliever NP COMM SVC Has Part Time ATCT — — — 3 3 Has No ATCT 6 21 4 3 6 — = no data. Source: SMQ Airport Services. TABLE 30 NUMBER OF AIRPORTS HAVING ATCT OPERATION Type of Radio Basic Local Regional Reliever NP COMM SVC Receiver/Transmit 1 1 7 6 6 Receive Only 5 20 — — — Combination 1 3 — 2 — — = no data. Source: SMQ Airport Services. TABLE 31 NUMBER OF AIRPORTS AND THE AVAILABILITY OF RADIOS INSTALLED IN THE SRE VEHICLES

35 Interviewees indicate the lack of signage is due primarily to the cost of installation for a low activity airport and that a hold line was considered adequate for their operation. However, pavement markings can be easily obscured by winter operations (Figure 16). Because of higher activity levels at the regional, reliever, and NPCS airports, those airports have appropriate signage installed, with the exception of one airport. For airports without signage, special snow removal effort is necessary to keep hold lines visible. ACCIDENTS AND INCIDENTS Despite the installation of signs and markings, airport surface incidents continue to occur. A surface incident is defined as an occurrence of an unauthorized or unapproved movement within the designated movement area (excluding runway incursions), or an occurrence in that same area associated with the operation of an aircraft that affects or could affect the safety of flight (FAA Order 7050.1A 2010). In essence, a surface incident occurs when a vehicle or person interferes with the movement of an aircraft other than on the runway. To help understand the hazards that can be present at small airports during winter operations, a survey question asked airport managers to identify various accidents or incidents over the previous three years (Table 33). Not all the accidents or incidents were reported to the FAA. Damage to light- ing was the highest reported incident in the survey. Lights are generally damaged as a result of the force of plowed snow or by being struck by a SRE. Although all of the circumstances referred to in Table 33 are safety issues, the prevalence of NOTAM issuance or cancellation issues and SRE break- age or maintenance are concerns for airport operators. They are also budgetary concerns because of the disruption, expense, and impact it can have on airport business activity. The study did not delve into the nature of the breakages. Incursion Prevention Basic (6) Local (21) Regional (7) Reliever (6) NP COMM SVC (6) Hold Lines Available 2 do not have All have All have All have All have Signs Available 3 do not have 10 do not have All have 1 does not have All have Source: SMQ Airport Services. TABLE 32 NUMBER OF AIRPORTS THAT DO OR DO NOT HAVE RUNWAY HOLD LINES OR SIGNS FIGURE 16 Example of obscured runway hold and taxiway centerline markings. Photo credit : S. Quilty, SMQ Airport Services.

36 SUMMARY The accumulation of snow and ice can greatly impede the performance characteristics of aircraft. Ice is reported to be the greatest challenge, but about one-third of the surveyed airports do not have the ability to use sand or de-icing/anti-icing chemicals owing to cost, equipment, and storage limitations. Friction measuring devices are not used at approximately half of the airports in the survey; however, the FAA has announced a new format for communicating runway conditions and the reporting of friction values will no longer be disseminated. The most frequent mishaps on airports in the survey during snow removal are damage to runway or taxiway lights. A surprising number of airports have experienced equipment breakage on the airfield or cannot use equipment because of maintenance issues. Incident/Accident Occurrence Basic Local Regional Reliever NP COMM SVC Vehicle or pedestrian incursion — 2 — 1 — Aircraft excursion due to poor friction — 2 — 1 — Aircraft collision with a snow bank 1 2 — — — Vehicle–aircraft collision (accident) — — — — — Near vehicle collision (incident) — 1 — 1 — Damaged lights from SRE operation 5 16 6 6 3 Damaged navaids from SRE operation 1 — 1 — 1 Vehicle breakage while on the airfield 2 8 5 3 2 Inability to use equipment due to a maintenance issue 1 9 4 3 2 Miscommunication between SRE operator and ATCT or aircraft — 3 — — 1 NOTAM not issued, revised, or cancelled properly — 6 2 4 3 — = no data. Source: SMQ Airport Services. TABLE 33 LIST OF ACCIDENTS OR INCIDENTS AT SURVEYED AIRPORTS OVER THE LAST THREE YEARS