NASA-LLIS-0617

Abstract

<strong>Description of Driving Event:</strong> <br>At approximately 4 p.m. on June 7, 1996, a liquid oxygen fire occurred in the "A" Leg of the LOX feed system for the 750k lb. position of Test Stand 116 located in the East Test Area of MSFC. The fire occurred as the "A" Leg engine shutoff valve reached the "20T open" position while closing after completion of the fourth of a series of six planned set point tests. These test were being conducted to provide data for establishing the correct throttle valve setting for subsequent planned hot fire testing of a 650k lb. Thrust Chamber Assembly provided by Rocketdyne. At the time of ignition, the "A" Leg shutoff valve had closed far enough to permit it to take control of the LOX flow from the venturi. The LOX fire started in the seat region of the valve, progressed from the engine shutoff valve outlet to the test article within 120 ms, and burned for approximately 25 seconds. For the first 8 seconds, the fire was fed by high pressure LOX. The fire partially consumed the lower part of the engine shutoff valve body, the two elbows and straight pipe section that connected the engine shutoff valve and the test article. The test article, all instrumentation devices, hydraulic fluid lines, control wires and cables on the stand were destroyed. The hydraulic fluid fire primarily charred pipe insulation and coated the test stand and its equipment with soot.