1、Lessons Learned Entry: 1627Lesson Info:a71 Lesson Number: 1627a71 Lesson Date: 2005-05-09a71 Submitting Organization: DFRCa71 Submitted by: Jonathan Browna71 Authored by: Tom GrindleSubject: Aircraft impact by crew entry/maintenance stand Mishap Investigation Abstract: On 4 April 2005, during a rout
2、ine double engine removal operation on a F-15B, tail number 836, at NASA Dryden, the aircraft center of gravity shifted forward, compressing the nose gear strut, and the right engine inlet contacted a crew entry/maintenance stand. The first engine removal was started at 0630 with a crew briefing con
3、cerning the engine removal. The crew consisted of 4 NASA mechanics. Only one crew member had done the task within the past year, all others were either new to the aircraft or had not performed an engine removal in the past year. More than one member of the crew verified that the crew entry stand was
4、 clear of the aircraft before starting the task. The first engine removal was nominal until the engine was being rolled back on the engine removal trailer, when some difficulty was experienced due to corroded rollers (a standard Air Force 4000 trailer). After the first engine was pushed back from th
5、e F-15B and was being transferred onto the transportation dolly (a standard Air Force 3000 trailer), a NASA technician assigned to the F-15B conducted a tour of the aircraft. He briefed the crew chief and lead technician that morning prior to conducting the tour and was given an OK. He did use the c
6、rew maintenance stand, and verified that the stand was clear of the aircraft. Due to the time involved with the first engine removal, the second was not started until after lunch (approximately 1330). The crew assumed that all equipment was still clear of the aircraft and proceeded to remove the sec
7、ond engine. The removal was nominal as was the transfer this time due to repairs made to the trailer. After the engine was removed and the trailer disconnected from the aircraft, the aircraft experienced a CG shift transferring weight forward on the F-15B, this is a normal occurrence when both engin
8、es are removed. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-At approximately 1430, the aircraft was being secured for maintenance and a NASA avionics/instrumentation technician (who was not involved with the engine removal, but assigned to the F-
9、15B) went to remove the canopy strut, close the canopy and move the crew maintenance stand. When he went to remove the stand, he could not pull it away from the aircraft. Upon further inspection, he found the right engine inlet resting on the stand. He then contacted the crew chief and they placed a
10、 nose jack under the F-15B, raising the aircraft high enough to remove the stand. No one was injured in this incident. The damage consisted of approximately 1.5” by 1.5” L-shaped deformation to the edge of the engine inlet. After inspection, no other damage was found. It was determined that the prim
11、ary factor for the incident was the lack of proper aircraft area inspection when the second engine removal was started. Other contributing factors were that the stand could have been designed to prevent this situation and wasnt, and the use of additional safety equipment (nose jack) is always an opt
12、ion to the task leader, even if the written procedures do not call for it. In addition, integrity of the incident scene is important. The aircraft should have been jacked up to stabilize it, but the stand left in place and photo called to document the incident. Description of Driving Event: On 4 Apr
13、il 2005, during a routine double engine removal operation on a F-15B, the aircraft center of gravity shifted forward, compressing the nose gear strut, and the right engine inlet contacted a crew entry/maintenance stand. All aircraft TO were followed correctly. Lesson(s) Learned: 1. A second check of
14、 the area should be performed by the crew chiefs whenever an aircraft is left unattended, and prior to starting or continuing any maintenance action.2. Crew chiefs always have the option of using extra safety equipment if they feel the need, even if the written procedures do not call for it.3. For a
15、ny mishap or incident, the integrity of the scene is critical. Crew chiefs need to understand that beyond stabilizing the aircraft, no further action should have occurred.Recommendation(s): The crew entry/maintenance stand should be modified to prevent placement under the F-15B inlet. Evidence of Re
16、currence Control Effectiveness: Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-N/ADocuments Related to Lesson: Aircraft Maintenance and Safety Manual Applicable aircraft technical order (TO)Mission Directorate(s): a71 Exploration Systemsa71 Aeronaut
17、ics ResearchAdditional Key Phrase(s): a71 Accident Investigationa71 Aerospace Safety Advisory Panela71 Aircrafta71 Ground Operationsa71 Mishap ReportingAdditional Info: Approval Info: a71 Approval Organization: DFRCProvided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
