Open Access

ARTICLE

Structural Analysis of the Right Rear Lug of American Airlines Flight 587*

I.S. Raju¹, E.H. Glaessgen¹, B.H. Mason¹, T. Krishnamurthy¹, C.G. Davila¹

1 NASA Langley Research Center, Hampton, VA, U.S.A.
* This paper received the ASME-Boeing Best Paper Award at the 46t h AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference in Austin, Texas, April 18-21, 2005.

Computer Modeling in Engineering & Sciences 2007, 22(1), 1-30. https://doi.org/10.3970/cmes.2007.022.001

Abstract

A detailed finite element analysis of the right rear lug of the American Airlines Flight 587 - Airbus A300-600R was performed as part of the National Transportation Safety Board's failure investigation of the accident that occurred on November 12, 2001. The loads experienced by the right rear lug were evaluated using global models of the vertical tail, local models near the right rear lug, and a global-local analysis procedure. The right rear lug was analyzed using two modeling approaches. In the first approach, solid-shell type modeling was used, and in the second approach, layered-shell type modeling was used. The solid-shell and the layered-shell modeling approaches were used in progressive failure analyses (PFA) to determine the load, mode, and location of failure in the right rear lug under loading representative of an Airbus certification test conducted in 1985 (the 1985-certification test). Both analyses were in excellent agreement with each other on the predicted failure loads, failure mode, and location of failure. The solid-shell type modeling was then used to analyze both a subcomponent test conducted by Airbus in 2003 (the 2003-subcomponent test) and the accident condition. Excellent agreement was observed between the analyses and the observed failures in both cases. The moment, M_x (moment about the fuselage longitudinal axis), had significant effect on the failure load of the lugs. Higher absolute values of M_x gave lower failure loads. The predicted load, mode, and location of the failure of the 1985-certification test, 2003-subcomponent test, and the accident condition are in very good agreement. This agreement suggests that the 1985-certification and 2003-subcomponent tests represent the accident condition accurately. The failure mode of the right rear lug for the 1985-certification test, 2003-subcomponent test, and the accident load case was identified as a cleavage-type failure. For the accident case, the predicted failure load for the right rear lug from the PFA was greater than 1.98 times the limit load of the lugs.

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