MIE222 Final Report: Fictional Aviation Accident Crash Report

Project Summary

Technical Director Dr. S.A. Meguid sent a memorandum to Chief Stress Engineer Pat McNeal, about the fictional crash of TAPA234 over Lake Ontario. We were tasked with analyzing the stiffened airframe design and providing a detailed technical report to defend TAPA from the claims of the families of the deceased passengers.

We analyzed the aircraft's stringer using four tests. The first test performed was a test of the material from which the stringer in question was manufactured, being Aluminium 6061-T6. A dogbone shaped sample of this material was tested to find the material’s mechanical properties. The second test performed was a Finite Element Analysis (FEA) of the stringer. A copy of the geometry of the stringer was created in ANSYS, and various tests were performed on it. The third test was a photoelastic examination of a copy of the stringer. This test corroborated the results of the FEA. The final test performed was a strain gauge test on a copy of the stringer. This test allowed us to find the maximum values that the material could withstand at any point on the geometry.

ANSYS Meshing and Simulation of the Stringer

Isochromatic Study of the Stringer

After performing the tests, the maximum force that could be exerted on the stringer ranged between 34.12 kN and 38.37 kN. There was also an outlier at 77.56 kN, but this test can be safely disregarded because it is larger than the range values. The outcome of the case rests on whether the stringer was subjected to conditions it was not built to handle, or conditions which were greater than the maximum stress that it could withstand at its critical point. If this happened, TAPA could lose the case based on overloading or failure to replace the part when it was fatigued. If the stringer was subjected to conditions that it was built to handle, TAPA might win the case because the part unexpectedly failed.