CH= 6 A/P OPS MGT UNDER FAR PART 139

Airport Operations Management Under FAR PART 139
                            Certification of Airport

FAR PART 139
      For A/Ps serving air carrier ops, FAA’s Regulations FAR Part 139-Certification and Operations, defines specific policies, activities, and standards for A/F ops mgt are to be followed
        FAR Part 139 applies to A/Ps that serve scheduled/unscheduled passenger air carrier ops that is conducted with A/C having a seating capacity of more than 30 passengers
        Regulations described in FAR Part 139 are designed to be broad ranging and general in nature, so applicable to any civil-use A/P
         Approx 700 A/Ps in the US are certificated to be in either full compliance or limited compliance with FAR Part 139
      FAR PART 139 

CERTIFICATION of AIRPORTS
      All A/P are required to create operational procedures specific to its unique environment that comply regulations listed in FAR Part 139
        For compliance, a comprehensive list of operational procedures are required to be compiled into an Airport Certification Manual (ACM)
        A/P in limited compliance are required to have a series of Airport Certification Specifications (ACS), which describe procedures in accordance with FAR Part 139
        FAA assesses an A/P’s compliance with A/P ops regulations mainly on basis of A/P’s ACM or ACS
A/P are required to have written plans for managing following areas
  1.  AIRFIELD PAVEMENT MGT
  2.  A/C RESCUE & FIRE FIGHTING (ARFF)
  3. SNOW AND ICE CONTROL
  4. SAFETY INSPECTIONS
  5. WILDLIFE HAZARD MANAGEMENT
 
PAVEMENT MANAGEMENT
      For most A/C, strong, level, dry, and well-maintained pavement surfaces are required for safe movement on A/P
        Thus inspection, maintenance, and repair of the runways, taxiways, and apron areas as part of A/F pavement mgt program are of utmost importance
        FAR Part 139, Section 139.305, covers some specific characteristics that define the minimum quality standards for airfield pavement

FLEXIBLE (ASPHALT) RUNWAYS
      Asphalt is less expensive than concrete, but requires much more maintenance in the long run
        Much depends on preparation/grading of underlying ground (subgrade), vigilance , and prompt attention to maintenance needs
        Moisture is the primary enemy
        If water does not drain off surface and away from the pavement edging quickly, it will filter to underlying layers of pavement and weaken it to the point where the overlying layers  break open
        Potholes then appear as heavy rains wash away loose material
        Similarly, years of use and by exposure to atmospheric conditions, asphalt R/Ws begin to lose their elasticity. When this occurs, cracks begin to appear on the pavement surface, which allows moisture to penetrate and further weaken the pavement
  Ultimately, when pavement is no longer able to support heavy loads, pavement failure occurs

CONCRETE RUNWAYS
      Concrete R/Ws/ T/Ws are found at large A/Ps with high volumes of air traffic because of their high load-bearing capabilities & resistance to the destructive effects of weather
        Concrete also resists deterioration from oil or fuel spillage better than asphalt, and for this reason is generally used for parking ramps and around hangars at all types of A/Ps
        Concrete, being a rigid material that expands and contracts with temperature change, is laid down in slabs separated by contraction and expansion joints
        Joints are filled with flexible binder, which either expands or shrinks as the concrete contracts or expands
      Concrete R/Ws/ T/Ws are found at large A/Ps with high volumes of air traffic because of their high load-bearing capabilities & resistance to the destructive effects of weather
        Concrete also resists deterioration from oil or fuel spillage better than asphalt, and for this reason is generally used for parking ramps and around hangars at all types of A/Ps
        Concrete, being a rigid material that expands and contracts with temperature change, is laid down in slabs separated by contraction and expansion joints
        Joints are filled with flexible binder, which either expands or shrinks as the concrete contracts or expands
      In colder temperatures, as concrete contracts, the joints might separate enough to admit material that is incompressible, such as sand or water when frozen
        When incompressible materials infiltrate the joints in concrete, tremendous pressures are generated during later expansion of the slabs, and the concrete might fracture in the joint area. This is known as spalling
        Fractured edges permit rain to seep under pavement surface, causing subgrade to washed away. This leads to empty foundation under the concrete slabs, which in turn causes the slabs to become misaligned and break
      Incompressible materials can also cause the slabs to pop out over adjacent slabs
        It can also cause slabs to buckle upward, cracking the surface and opening up areas for moisture to seep under the pavement surface
        Considerable amounts of concrete surface can be destroyed in a relatively short time because of poorly maintained expansion joints
        Even if the concrete slabs are misaligned only to a small degree, they present a hazard
 
        Landing gear, particularly nose wheels, can be significantly damaged, because irregular surfaces can blow tires and jerk airplanes out of control 

REMEDIAL SOLUTIONS
      Number of actions can be taken to repair the damages that occur in concrete and asphalt pavements
        Selecting an action is the degree to which the pavement has deteriorated
        Pavements that have little deterioration generally require moderate maintenance, whereas pavements that are more extensively deteriorated require rehabilitation or reconstruction
        FAA defines pavement maintenance as “any regular or recurring work necessary, on a continuing basis, to preserve existing pavement facilities in good condition, any work involved in the care or cleaning of existing pavement facilities, and incidental or minor repair work on existing pavement facilities.

PAVEMENT REHABILITATION
      FAA defines pavement rehabilitation as the “development required to preserve, repair, or restore the financial integrity” of the pavement.
         Adding an additional layer of asphalt on the surface of a runway with the goal of re-strengthening the pavement would be considered rehabilitation 

PAVEMENT RECONSTRUCTION
      Approaches to repairing pavements may differ, but experts say that suitably timed maint. and rehab prevents the need for pavement reconstruction, which is a far more expensive process
        An suitable maint. program can minimize pavement deterioration
        Similarly, rehabilitation can extend the time needed until the pavement must be replaced 

PAVEMENT MANAGEMENT PROGRAM
      A proper pavement management program evaluates the present condition of a pavement and predicts its future condition through the use of a pavement condition index
        By projecting the rate of deterioration, a life cycle cost analysis can be performed for various alternatives, and the optimal time of application of the best alternative is determined
      During 1st 75 % of its life, a pavement’s performance is relatively stable
        During last 25 % of its life, pavement begins to deteriorate rapidly
        Challenge of pavement mgt programs is to predict as accurately as possible when that 75 % life cycle point will be reached for a particular piece of pavement so its maintenance and rehabilitation can be scheduled at the appropriate times
        Longer a pavement’s life can be stretched until it must be rehabilitated, the lower the overall life cycle cost of the pavement will be
        According to FAA’s estimates, total costs for ignoring maint. and periodically rehabilitating poor pavement can be up to four times as high as the cost for maintaining the same piece of pavement in good condition 

EVALUATION OF THE PAVEMENT SYSTEM
      Accurate & complete evaluation of pavement system is one of the key factors contributing to the success of a maintenance project
        Major strides is development and application of non destructive testing (NDT)
        One of the most effective and valuable of the nondestructive techniques is vibratory or dynamic testing
        Technique measures strength of pavement system by subjecting it to a vibratory load and measuring the amount the pavement responds or deflects under this known load
        Rigid concrete pavements may also examined with this technique
        Testing of surface will reveal maint needed to upgrade the pavement system to the specifications as outlined in the A/P plan 

  RUNWAY SURFACE FRICTION
      One of the characteristics of R/W pavements is surface friction
        Surface friction allows A/C to safely accelerate for takeoff, and to decelerate after landing
        Lack of sufficient surface friction will result in A/C skidding, slipping, and general loss of control on the R/W surface
        R/W pavement surface friction is threatened by normal wear, moisture, contaminants, and pavement abnormalities
        Repeated traffic movements wear down the runway surface
      Wet weather can create dynamic or viscous hydroplaning
        Dynamic hydroplaning is a condition where landing gear tires ride up on a cushioning film of water on the runway surfaces
        Viscous hydroplaning occurs when a thin film of oil, dirt, or rubber particles mixes with water and prevents tires from making sure contact with pavement
        Contaminants, rubber deposits, and dust particles accumulate over a period of time and smother the surface. The pavement itself might have depressed surface areas that are subject to ponding during rainfall

 METHOD OF REDUCING HYDROPLANING
      Most effective & economical method of reducing hydroplaning is runway grooving
       1/4 inch grooves spaced approx 1.25 inches apart are made in the runway surface
        Safety grooves help provide better drainage on the R/W surface, furnish escape routes for water to prevent dynamic hydroplaning
        Grooving also assists in draining surface areas that tend to pond, reducing the risks of spray, fluid drag on takeoff
        Unfortunately, the grooves become filled with foreign matter and must be cleaned periodically 

REMOVAL OF RUBBER DEPOSITS AND OTHER CONTAMINANTS
 
      High-pressure water method 
 is based on high-pressure water jets aimed at the pavement surface to blast contaminants off the pavement surface. The technique is environmentally clean and removes deposits in minimum  time

      High-velocity impact method 
consists of throwing rough particles at high velocity at the runway surface. This technique blasts contaminants from the surface and can be adjusted to produce the desired surface texture

      Chemical solvents  
have also been used successfully to remove contaminants from both concrete and asphalt runways. Chemicals must meet environmental standards. Acid-based chemicals are used on concrete runways and alkaline chemicals on asphalt 

PAVEMENT MANAGEMENT PROGRAM
      Regardless of the type of pavement used on an airfield’s runways, taxiways, and apron areas, a prescribed plan for pavement inspection, maintenance, and rehabilitation is essential for the safe operation and movement of A/C at the A/P 

AIRCRAFT RESCUE AND FIRE FIGHTING (ARFF)
      Although the incidents of fires are rare, when they occur (especially on A/C), fire fighting and rescue capabilities at A/P may save life  of pilots, passengers, and A/P personnel
        Resultantly, ARFF services are required to be present at all A/P operating under FAR Part 139
        For those A/P not operating under FAR Part 139, agreement with local rescue and firefighting agencies is necessary for safe ops
      Characteristics of A/C fires are different because of the speed at which they develop and the intense heat they generate
       So FAR Part 139 designates specific ARFF requirements based on type of A/C that use A/P. Requirements are as follows
        FAR Part 139.315 designates the ARFF index of an A/C based on the length of  A/C  using A/P and average no of daily departures of  A/C
        FAR Part 139.317 describes the required ARFF equipment and agents to be present at A/P, based on the A/P’s ARFF index
        It indicates a min response time of the first vehicle to an incident
        It suggests that all ARFF training curriculum should be held
        At least, one ARFF person on duty must be trained in emergency medical care
        It requires all ARFF personnel to participate in at least one live-fire drill every 12 months

SNOW AND ICE CONTROL
      Removal of snow and ice from A/F pavements  consume significant portion of A/P’s ops budget
        FAR Part 139.313, states that all A/Ps where snow and icing conditions regularly occur shall prepare, maintain, and carry out a snow and ice control plan
        Snow and ice control plans should include ATC comm, safety considerations, inspection standards, and notice to airmen (NOTAM) responsibilities

SNOW LIMITATIONS FOR AIRCRAFT
      Large jet A/C have takeoff limitation of 1/2 inch of heavy wet snow, and 1 inch of snow of medium moisture content
        So removal ops must start before such conditions occur, and must continue without interruption until the end of snowfall and snow removal has progressed to the point where A/C ops may be carried on with safety
        Snow removal ops are started on the active R/W and progress to other R/W & T/Ws
        In tandem, snow clearing from ramps, A/C loading positions, service areas, and public facilities also takes place

METHODS OF REMOVING SNOW AND ICE
      Two basic methods of removing snow and ice: mechanical and chemical
 
Mechanical Means
      Most removal is accomplished by mechanical means, because chemical methods are generally more expensive and less effective
      Underground hot water and electrical heating systems are used around ramps areas at some large airports
       Such systems are very expensive to construct and maintain, preventing them from implementation at most airports. The three mechanical methods of snow removal include plows, blowers/throwers, and brushes
 
  Chemical Means
       For airfield pavements, different types of chemicals may be used to prevent or remove snow and use accumulations
        Such chemicals include urea, acetate based compounds, and sodium formate
        Urea is effective in removing ice and snow in temperatures as low as 15 deg Fahrenheit
        Acetate-based compounds are known to be effective in temperatures as low as -50 deg Fahrenheit 

  ICE ACCUMULATION
      Snow accumulation pose serious risks to the safety of A/F ops as ice is the greatest hazards to A/C ops
        Many A/P attempt to control such conditions through the use of sand but dry sand spread on R/W and T/W is quickly removed by A/C engine blast, so a means of securing the sand to the ice is necessary
        Most successful method uses conventional weed-burning equipment. The procedure is to apply sand to the icy surface. These lay down a uniform layer of sand. This is immediately followed by flame-thrower type burner units, which heat the sand particles and melt the ice sufficiently to produce coarse, sandpaper like surface upon refreezing

  AIRCRAFT DEICING 
      Presence of ice or snow accumulation on A/C’s wings or fuselage has potential adverse effects on the performance of A/C in flight
        So removal of accumulations is required prior to flight. This removal process is known as aircraft deicing
        A/C deicing is accomplished by spraying one of two types of heated aqueous solutions onto the aircraft
       Heat of the solution and the force of the spray melt and remove the accumulation. The chemical properties of the solution act as an antifreeze to prevent significant accumulation prior to takeoff

  SAFETY INSPECTION PROGRAMS
      To ensure FAR regulations, A/P mgt should carry out comprehensive safety inspection program
        Frequency of inspections varies by A/P, but certain facilities and equipment (R/W, T/W, and nav aids) must be inspected daily
        FAA’s Airport Certification Program Handbook suggests the following general categories in which emphasis on elimination, improvement, or education should be placed
        Hazards by weather conditions such as snow, ice, and slush
        Obstacles on and around airfield surfaces
        Hazards that threaten the safety of the public
        Hazards created by erosion, or broken or damaged facilities
        Hazards occurring on A/P during construction activity, such as holes, ditches, obstacles
        Bird hazards adjacent to the airport
        Inadequate maintenance personnel or equipment 

BIRD AND WILDLIFE HAZARD MANAGEMENT
      Birds and wildlife striking A/C in operation at A/P has the potential to cause serious damage to A/C and loss of human life
        In 2001, over 5,600 aircraft reported a wildlife strike, nearly five times the amount reported in 1990
        An estimated $400 million/yr in A/C damage and over 500,000 hrs/yr of A/C downtime was associated with these events
        Because most strikes occur on or near airports, emphasis on bird and wildlife management is mandated
        FAR Part 139.337 directs A/Ps to conduct a study and provide a wildlife management program for A/P 

  BIRD HAZARD
      A flock of birds ingested into a jet engine at takeoff can cause a dangerous stall, and a single large bird hitting an engine with the force of a bullet might smash a fan blade that can cost thousands of dollars to replace
        FAR Part 139 requires that A/P operators must established instructions and procedures for the prevention or removal of factors at the A/P that attract, or might attract, bird activity
        Most allowable control techniques are intended to discourage birds from feeding at the airport
        Use of trained birds of prey, such as falcons and hawks, complements a number of other measures
        Several airports have turned to border collies as an effective way to chase birds

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