Foreign Object Debris and Damage
Prevention
Foreign object debris (FOD) at
airports can cause damage that costs airlines, airports, and airport tenants
millions of dollars every year. FOD is any object that does not belong in or
near airplanes and, as a result, can injure airport or airline personnel and
damage airplanes. A FOD-prevention program of training, facility inspection,
maintenance, and coordination between all affected parties can minimize FOD and
its effects.
Foreign object debris
(FOD) at airports includes any object found in an inappropriate location that --
as a result of being in that location -- can damage equipment or injure airplane
or airport personnel. The resulting damage is estimated to cost the aerospace
industry $4 billion a year. Airports, airlines, and airport tenants can reduce
this cost by taking steps to prevent airport FOD.FOD includes a wide range of
material, including loose hardware, pavement fragments, catering supplies,
building materials, rocks, sand, pieces of luggage, and even wildlife. FOD is
found at terminal gates, cargo aprons, taxiways, runways, and run-up pads. It
causes damage through direct contact with airplanes, such as by cutting airplane
tires or be
ing ingested into
engines, or as a result of being thrown by jet blast and damaging airplanes or
injuring people.
A program to control
airport FOD is most effective when it addresses four main
areas:
1 Training.
2
Inspection by airline, airport, and airplane handling agency personnel.
3
Maintenance.
4 Coordination.
1 TRAINING
All airport
and airline personnel and airport tenants should receive training in the
identification and elimination of FOD, including the potential consequences of
ignoring it. This training can supplement the general FOD awareness incorporated
into the airside driver-training curriculum at many airports. FOD training for
flight crews includes following the recommended procedures identified in the
Flight Crew Operating Manual and pre- and postflight inspection procedures
covered during line training.
Effective training should
stress safety to personnel and passengers, the hazards to equipment, the direct
costs associated with FOD damage, and the indirect costs associated with flight
delays and rescheduling. It should also include procedures for removing and
eliminating FOD at its source, and should be reinforced through the use of
posters and signs. Recurrent training is necessary to help maintain an awareness
of FOD.
2 INSPECTION
Airline
personnel, when feasible, should join the airport staff in daily airside
inspections. This practice helps increase familiarity with local airfield
conditions, and promotes effective communication between the airport and
airlines.
The U.S. Federal Aviation
Administration (FAA) and International Civil Aviation Organization (ICAO)
require a daily, daylight inspection of airplane maneuvering areas and removal
of FOD. In addition to performing these inspections at the beginning of the day
or shift, personnel on the airside should look for FOD during their normal
shifts.
Ongoing construction
requires more frequent inspections. It may even be necessary to assign dedicated
personnel to continually inspect for FOD during major construction activities.
Flight crews should report to air traffic control and station operations any FOD
they observe on runways and taxiways. Airlines and airplane handling agents
should designate individuals to inspect gate areas prior to airplane movement to
and from the gate.
3
MAINTENANCE
Maintaining control of FOD includes using several
methods:
Sweeping. Sweeping may be done manually or
with the airfield sweeper, which is the most effective equipment for removing
FOD from airsides. The sweeper removes debris from cracks and pavement joints,
and should be used in all areas except for those that can be reached only with a
hand broom. All airside areas, including aircraft maneuvering areas, aprons and
gates and the areas adjacent to them, should be swept routinely. The areas in
which ground support equipment (GSE) is staged should be swept
periodically.
Magnetic bars. These bars can be suspended
beneath tugs and trucks to pick up metallic material. However, the bars should
be cleaned regularly to prevent them from dropping the collected debris.
Vehicles operating on the airside should be inspected periodically to ensure
that they have no loose items that can fall off.
Rumble strips. Driving over rumble strips
dislodges FOD from vehicle undercarriages. The strips, which are 10 to 15 ft
long, can be moved and used at transitions from the landside to the airside, or
adjacent to airside construction areas.
FOD containers. These containers should be placed
at all gates for the collection of debris. The containers should be emptied
frequently to prevent them from overflowing and becoming a source of FOD
themselves. In addition, airport personnel can wear waist pouches to collect
debris. Evaluating the debris collected in containers and pouches can reveal its
sources and indicate where personnel and equipment should be deployed for more
effective control.
Other means for preventing FOD
damage include wind barriers and netting to restrict the movement of airborne
FOD, fencing to prevent animals from entering the airfield, and well-maintained
paved surfaces. If damaged pavement cannot be repaired immediately, airplanes
should take an alternate route.
COORDINATION
Airports with a
FOD committee of airport tenant representatives tend to control FOD more
successfully than those without such a committee because the representatives can
address local conditions and specific problems. At airports served by multiple
airlines, the airlines should have these representatives as well as an airport
user's committee to coordinate FOD control efforts among
themselves.
Both airside and landside
construction activities, as well as scheduled maintenance, should be
communicated to airport users as early as possible. Airport preconstruction
planning should include a means for controlling and containing FOD generated by
the construction. This is especially true in high-wind environments where debris
is more likely to become airborne. Access to and from construction sites should
avoid areas of aircraft operation. Contractors must fully understand the
requirements and penalties incorporated in their contracts regarding the control
and removal of FOD.
FAA Advisory Circulars
150/5380-5B, Debris Hazards at Civil Airports, and 150/5370-2C, Operational
Safety on Airports During Construction, provide excellent guidelines for
coordinating day-to-day FOD prevention during
construction.
SUMMARY
An effective
debris-control program can greatly reduce the high cost of FOD damage and the
potential for injury to personnel. The program is founded on initial and
recurring training, and it is carried out through the inspection and maintenance
of airport facilities. FOD control is most effective when all affected parties
coordinate their efforts.
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BOEING FOD AUDITS
Boeing is
available to perform an operational FOD audit upon request. The audit provides
an independent review of existing conditions, and results in recommendations for
enhanced debris control. It includes a review of maintenance and servicing
procedures, installation of recommended service bulletins, a review of flight
crew operating procedures, and an inspection of the airport operating
environment, including FOD-avoidance procedures used by ramp and airport
personnel.Operators may use audit findings to develop corrective procedures and
training programs, and to improve coordination between operators, airport
personnel, and airport tenants.
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|
FOD AND MAINTENANCE COSTS | |
|
The effect of
Foreign Object Debris (FOD) on maintenance costs can be significant. For
example, the cost to repair a FOD-damaged engine can easily exceed $1
million. FOD can also incur extensive indirect costs,
including:
The cost of
repairing FOD damage to an engine can easily exceed 20 percent of its
original purchase price. | |
|
Purchase cost of MD-11 engine |
$8-10 million |
|
Purchase cost of MD-80 engine |
$3-4 million |
|
MD-11 engine overhaul to correct FOD damage |
$500,000-1.6 million |
|
MD-80 engine overhaul to correct FOD damage |
$250,000-1.0 million |
|
MD-11 fan blades (per set*) |
$25,000 |
|
MD-80 fan blades (per set*) |
$7,000 |
|
*Fan blades are balanced and replaced as a set. | |
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RESPONSIBILITY FOR PREVENTING
FOD
The two main parties with a role in preventing foreign object debris
(FOD) and the potential resulting damage are airports and
airlines.
Airports. Regulatory agencies define the
responsibility of airports serving scheduled airlines. Regulations defined by
the U.S. Federal Aviation Administration for U.S. airlines differ from those
defined by the International Civil Aviation Organization (ICAO) for other
countries.
FAA Part
139.305(a)(4)
states, "except as provided in paragraph (b) of this section, mud, dirt, sand,
loose aggregate, debris, foreign objects, rubber deposits and other contaminants
shall be removed promptly and as completely as practicable." FAA Advisory
Circular 150/5200-30A, Airport Winter Safety and Operations, specifies cleanup
requirements for sand applied during winter operations.
ICAO Annex 14
Recommendation,
Pavements-paragraph 9.4.2 states, "The surface of pavements (runways, taxiways,
aprons, etc.) should be kept clear of any loose stones or other objects that
might cause damage to airplane structures or engines, or impair the operation of
airplane systems." The regulatory agencies of many countries have adopted this
statement by ICAO as a requirement.
Airlines. Airlines and airport tenants
generate much of the FOD found in gate areas, service roads, baggage makeup
areas, and areas near flight kitchens. Agreements between airlines and their
support organizations should specify which of the parties are responsible for
cleaning various areas.
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SOURCES OF FOD
Foreign object
debris (FOD) comes from many sources. The most common are:
Airport
infrastructure.
The deterioration, maintenance, and construction of the airport infrastructure
can contribute to FOD. For example, pieces of concrete can break loose from
holes in pavement or from fatigue corner cracks, and building materials can fall
from construction vehicles or be blown from gate areas onto airplane maneuvering
areas. Broken pieces of pavement can collect at the edge of the gate area and be
carried onto the airplane maneuvering area by the tires of vehicular ground
support equipment (GSE). Service roads that cross taxiways should be monitored
closely to prevent the vehicles using these roads from moving FOD onto the
taxiways.
Normal aircraft operations.
Refueling,
catering, cabin cleaning, and baggage and cargo handling can produce broken
materials. Baggage pieces, including bag tags and wheels, can break off luggage
and either fall onto the apron or collect in the door sill. Items collected in
the door sill can damage the door or prevent it from fully sealing. They can
also be knocked out of the sills and onto the apron at the next station. Other
areas where FOD is likely to collect include the ground at both ends of the
conveyor, and the area between the baggage cart and the conveyor
belt.
Maintenance activities at the gate
require a variety of small objects, such as rivets, safety wire, and bolts, that
become FOD when they are inadvertently left behind. An effective tool control
program will reduce the number of missing hand tools.
FOD typically peaks during the
early spring, when airports often begin construction activities, and during the
winter because of operations in snow and ice. Issued by the U.S. Federal
Aviation Administration, Advisory Circular 150/5200-30A, Airport Winter Safety
and Operations, contains specific guidance on using and removing sand to
minimize its chances of becoming FOD in winter weather
conditions.
Aft galley catering operations
through the aft main deck door can be a potential FOD hazard to a rear-mounted
No. 1 engine not protected by an inlet cover. Without the cover, catering
supplies can be set down in the engine intake, where they can be inadvertently
left behind. These supplies can also fall or spill their contents into an
unprotected engine.
FOD can collect both on and below
ground support equipment stored or staged adjacent to the gate area. Jet blast
can then blow FOD onto personnel or an airplane. It can also create runway FOD
when an airplane transitions from a 150-ft-wide runway onto a 75-ft-wide taxiway
(figure 3). Outboard engines blow any loose dirt and materials from the shoulder
and infield areas back onto the runway. Also, the outboard engines of
four-engine airplanes can move debris from the runway edge and shoulder areas,
where it tends to accumulate, back toward the center of the runway or
taxiway.
Helicopters that maneuver over
freshly mowed or loose-dirt infield areas can also move FOD onto runways,
taxiways, and ramps. In addition, the rotor wash from a helicopter can propel
lightweight GSE or materials staged nearby.
Personal
belongings. Pens,
coins, identification badges, hats, soda cans, paperwork, and any other object
that airport or airline personnel carry can become FOD if inadvertently left in
an inappropriate location.
Brad
Bachtel
Senior Staff
Engineer
Airport Technology Office
Douglas Products Division
© 1998 The Boeing Company. All rights
reserved.