American Airlines Flight 191 - Case Study Example

Instead of carrying out the procedure according to the accompanying directions, American Airlines decided to replace the assembly via a cheaper method that involved less time and effort to undertake."Postaccident investigation revealed that a portion of the upper forward flange ofthe aft bulkhead had been fractured by overload in the inboard-outboard directionjust forward of the radius between the flange and the bulkhead plane. The fracturehad been initiated by a downward bending moment at the center section of the flangejust forward of the fracture plane due to contact between the clevis and the flange.

As a result of this contact, the aft fracture surface of the upper flange was deformedinto a crescent shape that matched the shape of the lower end of the wing clevis.The length of this overload fracture was 10 inches. Fatigue cracking was present atboth ends of the overload fracture, and the total length of the crack due to both overloadand fatigue was 13 inches" (Failure Analysis, 2008, pg. 1).The aft bulkhead could have been brought into contact with the wing-mounted clevis via a number of different ways.

Either during or after the hardware in the aft bulkhead fitting was removed, a load could have been applied that would have been sufficient enough to produce a crack. When attaching the pylon, the maintenance personnel had to be extremely careful because of the small distance between the pylon and wing attachments and the structural elements. It would only take a minor error for the forklift operator to damage the bulkhead and its upper flange (Failure Analysis, 2008). "The structural separation of the pylon was caused by a complete failure of theforward flange of the aft bulkhead after its residual strength had been reduced bythe fracture induced during the maintenance operation as well as by additional fatiguecrack growth in service.

It is also clear the poor communications between engineeringand maintenance personnel, and between the FAA, the manufacturer, andthe airlines contributed to this accident" (Failure Analysis, 2008, pg. 1). Overall, an effort to maintain the aircraft in a cheaper fashion on the part of American Airlines was the ultimate cause of the disaster. Had the Tulsa, OK maintenance facility followed McDonnell-Douglas' initial instructions for the procedure, the crash may never have happened in the first place.

This has, thus, become a case study since then as to what can happen when the wrong corners are cut.