X-37: ALTV STRUCTURAL PROOFLOAD TEST

摘要

The following paper will discuss the challenges of the X-37: ALTV (Approach Landing TestVehicle) Structural Proofload Test. The challenges discussed will be in the following areas:Analysis, Test Build-up, and in Conducting the Test.The main objective of the X-37 ALTV Structural Proofload Test was to verify the structuralintegrity of the X-37 primary structure at proof load levels (1.2 X DLL). This was accomplishedby verifying the applied loads, measured reaction loads, and strain and deflection gaugemonitoring of key structures to pretest predictions. The unique test setup and all compositeprimary structure of the X-37, with both bonded and bolted joints, created a unique situation forverifying both the measured reaction loads and strain gauge measurements against pretestpredictions. The analysis portion of this paper will address the challenges and solutions faced bythe analysts during and after the structural proofload test.The test build-up incorporated some new and innovated techniques to solve inherent difficultiesassociated with this test vehicle. The test fixture incorporated for this test was used before tosimulate the Space Shuttle Cargo Bay, which tested the Space Station Truss Segments (S1 andS0). In addition to this test fixture, a separate beam structure was designed to interface with theB-52 Canopy on the X-37 vehicle. The benefit of this structure was two fold. One, it was usedto transport the test vehicle in and out of the Space Shuttle Cargo Bay simulated fixture. Two, isthe main reaction structure for the test vehicle under structure loads. In this paper, the authorwill discuss the advantages and disadvantages of using this fixture.Conducting the X-37: ALTV Structural Proofload Test was a challenge. The program scheduleand budget left no room for error. The test team was under excruciating pressure to meet all theobjectives of the test, on schedule and on budget. The authors of this paper will discuss howthey meet all the objectives, for a successful structural test.