A new research apparatus has been developed to study the effect of gravity levels in a drop tower environment. A centrifuge test device was installed inside a drop rig used in the Zero-Gravity Facility at NASA Glenn Research Center. The centrifuge consists of a large rotating chamber with rotation rates up to 1 RPS with no measurable effect on the overall Zero-Gravity drop bus. Gravity levels from zero to lg (at a radius of rotation : 30 cm) can be produced. Experiments were conducted to examine the maximum oxygen concentration at which three different materials ignited in lunar gravity would self-extinguish. All three materials burned to lower oxygen concentrations in lunar gravity than in normal gravity, although the low-g extinction limit criteria are not the same as lg due to time constraints in drop testing. The margin of safety of the lg test method relative to actual low gravity material performance is presented. In broader application, a modified Test 1 protocol is suggested to provide the option of selecting better materials based on the best margin of safety relative to the use environment, as opposed to what would be considered just "passing" from a flammability point of view. This paper discusses these results and demonstrates that the Zero-Gravity Centrifuge is a useful tool for researchers interested in the effects of partial gravity on experiments, especially as NASA embarks on future missions which may be conducted in non-Earth gravity.
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