Ozone effects on construction materials for the stationary high-altitude relay platform (SHARP) aircraft

The effects of low concentrations of ozone on modern aircraft construction materials was investigated, as relates to the SHARP (Stationary High-Altitude Relay Platform). A mission of one year was simulated by increasing ozone concentration and pressure from the flight parameters, in order to accelerate the tests.;The materials tested were graphite-reinforced epoxy and PEEK (a thermoplastic matrix), e-glass-epoxy, Kevlar-epoxy, balsa and basswood, Kapton, Mylar, Tedlar, Delrin, and nylon. No definite effects were seen for any of the man-made composites. The woods showed no measurable degradation, but the odour of the samples after exposure indicated that a reaction was taking place. Kapton may have been very slightly affected. Nylon, however, showed substantial surface stickiness due to exposure, rendering it unsuitable as a construction material. All of the other materials may be considered inert to ozone for SHARP purposes.