A15.6.4. Examples of Hazardous and Marginal Conditions. Analyses of past accidents and incidents
identified many contributory hazards and conditions. A representative list follows:
A188.8.131.52. Excavation adjacent to runways, taxiways, and aprons.
A184.108.40.206. Mounds or stockpiles of earth, construction material, temporary structures, and other
obstacles in proximity to airport operations areas and approach zones.
A220.127.116.11. Runway surfacing projects resulting in excessive lips greater than 1 inch (2.54 cm) for
runways and 3 inches (7.62 cm) for edges between old and new surfaces at runway edges and ends.
A18.104.22.168. Heavy equipment, stationary or mobile, operating or idle near airport operations areas
or in apron, taxiway, or runway clearance areas.
A22.214.171.124. Proximity of equipment or material which may degrade radiated signals or impair
monitoring of navigational aids.
A126.96.36.199. Tall but relatively low visibility units such as cranes, drills, and the like in critical areas
such as apron, taxiway, or runway clearance areas and approach zones.
A188.8.131.52. Improper or malfunctioning lights or unlighted airport hazards.
A184.108.40.206. Holes, obstacles, loose pavement, trash, and other debris on or near airport operations
A220.127.116.11. Failure to maintain fencing during construction to deter human and animal intrusions
into the airport operation areas.
A18.104.22.168. Open trenches alongside operational pavements.
A22.214.171.124. Improper marking or lighting of runways, taxiways, and displaced thresholds.
A126.96.36.199. Attractions for birds such as trash, grass seeding, or ponded water on or near the
A188.8.131.52. Inadequate or improper methods of marking temporarily closed airport operations
areas including improper and unsecured barricades.
A184.108.40.206. Obliterated markings on active operational areas.
A220.127.116.11: Encroachments to apron, taxiway, or runway clearance areas, improper ground
vehicle operations, and unmarked or uncovered holes and trenches in the vicinity of aircraft
operating surfaces are the three most recurring threats to safety during construction.
A15.6.5. Vehicles on the Airfield. Vehicular activity on the airfield movement areas should be kept to
a minimum. Where vehicular traffic on airfield operational areas cannot be avoided, it should be
carefully controlled. A basic guiding principle is that the aircraft always has the right-of-way. Some
aspects of vehicle control and identification are discussed below. It should be recognized; however,
that every airfield presents different vehicle requirements and problems and therefore needs
individualized solutions so that vehicle traffic does not endanger aircraft operations.
A18.104.22.168. Visibility. Vehicles which routinely operate on airport operations areas should be
marked and or flagged for high daytime visibility and, if appropriate, lighted for nighttime
operations. Vehicles which are not marked and lighted may require an escort by one that is
equipped with temporary marking and lighting devices. (See USAF TO 36-1-191, Technical and
Managerial Reference for Motor Vehicle Maintenance, and Federal Aviation Administration