Project 8.4 = Thermal Effects on the Strength of Aircraft Structural Sandwich Type Panels - LCDR A. Julian OBJECTIVE The objective of this project was to determine the effects of shortduration, high intensity thermal inputs on the strength of aircraft structural sandwich type panels, and thereby to establish critical temperature limits for delivery of special weapons by aircraft utilizing this type of construction. Two distinct efforts are required to accomplish the objective of Project 8.4; a field phase and a laboratory phase. The field phase, accomplished with participation on ah 2? Shot (CHEROKEE), is directed toward measuring the temperature-time history in the specimen panels, and making visual observations of panel behavior under irradiation. The laboratory phase will be to determine the strength and moduli changes in irradiated panels as a result of transient heating of the type producing the temperature-time histories measured in the field test. INSTRUMENTATION Instrumentation for the field phase of Project 8.4 consisted of exposing several types of representative aircraft structural sandwich panels to thermal radiation effects. The test display, erected at Station 840,01 on Aomoen (GEORGE) contained several types of instrumented panel specimens in no-load mountings. Also, panels of a variety of face gages (0.008 inch to 0,032 inch) and colors (gray and white) were exposed in an attempt to obtain variations in temperature rise. Temperature history was taken by thermocouples mounted on the panels and was recorded as a function of time. CoieD Lint peO0g - 8 -