Aeronautics Study - Safety Threats Term Paper

Excerpt from Term Paper :

Percentage (a)

System operated unsafely during maintenance 80 13

Incomplete installation 48 8

Maintenance worker contacted hazard 45 7

Incorrect assembly or location 44 7

Towing event 44 7

Vehicle or equipment contacted aircraft 31 5

Material left in aircraft 27 4

Wrong equipment or part installed 23 4

Part not installed 22 4

Part damaged during repair 21 3

Panel or system not closed 21 3

Required service not performed 20 3

Failure of component or tool 15 2

Fault not found 15 2

Falls and trips 14 2

System not made safe before maintenance 12 2

System not reactivated 10 2

Pin or tie left in place 9 1

Documentation error 9 1

Note. For an additional 14 occurrences, the outcome could not be determined.

A a) Figures are rounded to nearest percentage.


Perceptual error

Example: After being on duty for 18 hr on a long overtime shift, the worker was carrying out a general inspection on an engine at around 22:00. He missed obvious damage to the internals of the cold stream duct area. The damage was found later, when another defect was being investigated.

Memory lapse

Example: Just prior to the departure of the aircraft, I remembered I had left a blanking plug within the engine inlet area. I advised the pilot that I needed to check that area again and retrieved the blank.


Example: Without thinking, I moved to wipe oil with a rag. The rag was ingested in the engine intake causing FOD [Foreign Object Damage].

Rule-based error

Example: A mechanic did not check the position of the flap lever before he pushed in a cockpit circuit breaker that provided electrical power to a hydraulic pump. When the pump started, the flaps began to retract automatically. This could have caused damage to the aircraft or injured other workers.


Example: At the end of a shift we realized that an engine hadn't been run to check for oil leaks when the aircraft was to be placed online. Under pressure to avoid a delay due to this oversight, the run was carried out too quickly and the engine was not un-cowled properly to check for oil leaks and consequently after departure that particular engine ran out of oil as the result of a damaged seal.

Knowledge-based error

Example: I wanted to turn the radio master on but could not find it, as the switches were poorly marked or unreadable. I was unfamiliar with the aircraft, so I asked an airframe tradesman who was working on the aircraft and he pointed to a red rocker switch. I queried him and he said that must be it. I pushed the switch and the right engine turned over, with the propeller narrowly missing a tradesman who was inspecting the engine. There is no radio master in this aircraft. I immediately marked the "start" and some other switches and learned a valuable lesson.


Example: A service procedure was carried out in accordance with the aircraft maintenance manual. The manual however, contained an error, which resulted in an aircraft system failing to operate correctly during a functional test at the end of the maintenance procedure.

Factor n or Fatigue 1-0.2

Pressure 8-1.9

Coordination 6-1.4

Training 1-0.2

Supervision 5-1.9

Procedure 16 9.0 **

Equipment 1-0.3 deviation 4-4.3 *

Environment 1-0.8 chi square](9, N = 805) 46.68

Wald test significant at p

Cite This Term Paper:

"Aeronautics Study - Safety Threats" (2007, November 25) Retrieved February 21, 2018, from

"Aeronautics Study - Safety Threats" 25 November 2007. Web.21 February. 2018. <>

"Aeronautics Study - Safety Threats", 25 November 2007, Accessed.21 February. 2018,