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
- AIRFIELD PAVEMENT MGT
- A/C RESCUE & FIRE FIGHTING (ARFF)
- SNOW AND ICE CONTROL
- SAFETY INSPECTIONS
- 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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