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- Aluminum 6061-O was chosen as the material because welding the inner step probably eliminated its temper.
- No connections were set.
- The outer step was chosen as the fixed geometry. Technically, the Avionics Bay Coupler only constrains the outer step in one direction (the vertical direction), but the bulkhead is also constrained radially within the Avionics Bay Coupler by the inner step. The bulkhead is not strictly constrained circumferentially except by friction after putting the Avionics Bay Coupler under compression (in an ideal execution of the design, which was not necessarily achieved for this test): this is irrelevant to the load applied.
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