LDEF (Prelaunch), M0003 : Space Environment Effects on Spacecraft Materials, Tray D04 The prelaunch photograph was taken in SAEF II at KSC prior to installation of the integrated tray on the LDEF. The Spacecraft Materials Experiment hardware consist of four LDEF peripheral trays (two sets), two Experiment Power and Data Systems (EPDS), two Environment Exposure Control Canisters (EECC), twelve LiSO2 batteries and internal support structure, instrumentation and black anodized aluminum mounting plates for experiment samples. The experiment structural members were assembled using nonmagnetic stainless steel fasteners. One six inch tray and one three inch tray with a connecting wiring harness, one EPDS, one EECC and six LiSO2 batteries were located in tray locations D08 and D09 near the LDEF leading edge and a similar set of hardware was located near the LDEF trailing edge in tray locations D03 and D04. The environmental exposure was similar with one significant exception, the trailing edge location was not exposed to continuous bombardment by the relativity high atomic oxygen flux. The experiment tray in the D04 location is divided into three sections.The right section provides space for the EPDS, the center section accommodates the Signal Conditioning Unit (SCU) and an experiment mounting plate, on an aluminum sub-structure, populated with a composite material samples. The left section houses the EECC with its complement of experiment samples consisting of coatings, thermal paints, polymers, glasses, semi-conductors. Detectors within the experiment provide environmental data for use in postflight analyses. Batteries and inter-tray connections are located beneath the tray base plates. The EPDS is underneath an aluminum cover, coated with a white thermal control paint (Chemglaze II A-276) and thermally isolated from the tray structure by fiberglass clips. The SCU cover is also coated with a white thermal control paint, IITRI S13G-LO, and the EECC is covered with a chromic anodized aluminum thermal cover.
