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A piece of suspected reentry debris was submitted to the Materials Science Department for analysis to determine whether its composition was consistent with its supposed source. The debris consisted of a black-colored woven fabric that locally had clear fused-looking areas, with entrapped bubbles, and small metallic deposits. The time and location of the recovered debris correspond with the reentry of a Delta II second stage. The second-stage fuel tank, thrust chamber, and a pressure vessel impacted at several locations in Texas, and trajectory analysis, allowing for the prevailing winds, shows that the recovered debris is probably from the reentry event. The chemical composition of the fibers (calcium alumino silicate) and appearance of the piece of debris is consistent with it being from the outer woven E-glass fabric from the Delta second-stage thrust chamber. The metallic deposits on the fabric are believed to be residue from the aluminum flange. E-glass has a 'softening' point of about 850 deg C and a 'melting' point of approximately 1200 deg C. The large number of bubbles trapped in the fused glass is also consistent with the orbital reentry scenario and assumes the material was relatively fluid and had reached a temperature above the melting point of E-glass.

A prototype Multiparameter Sensor System (MPS) is described for impact detection and environmental condition monitoring of graphite epoxy composite structures. This system is applied to a full-scale inert Delta-II solid rocket Graphite Epoxy Motor (GEM) casing. Microelectro-mechanical (MEMS) sensors are used in this demonstration, including those for 3-axis acceleration, temperature, pressure and humidity. All sensor measurements are made within a single package mounted at the center of mass of the test article. Sensor analog outputs are sampled with a National Instruments Inc. data acquisition PCMCIA card, and data is processed on a Pentium-II 200 MHz laptop computer. Sensor information collected during this demonstration was passed wirelessly to a remote user terminal for display and data storage. Data presented in this report includes peak acceleration for impacts just below damage threshold, environmental sensor trends, and wireless RF performance in a warehouse environment.