The Naval Ordnance laboratory's participation in Operations Redwing and Teapot included the measurement of drag forces on staple model shapes under atomic blast conditions. Later, laboratory tests were performed on the same (identical) models. These tests were performed both in wind tunnels and in shock tubes to determine whether laboratory tests could adequately substitute for field tests and thus permit better understanding and elaboration of the field data from the atomic operations. Since the test models ranged in size from three to ten inches (in the characteristic dimension) and because of the limited size of the SOL wind tunnel and shock tube facilities, almost all laboratory tests were performed at other locations such as the Ballistic Research Laboratories, David Taylor Model Basin, and Armor Research Foundation. Each of these test series became, in itself, a small scale field operation with the adverse conditions of tight scheduling between agencies, transportation of equipment, testing under less than optimum conditions, and inability to repeat or elaborate upon tests after the data had been completely reduced and analyzed. In view of these difficulties it was decided that a small force gage, which could be used in the NOL 4-inch by 8-inch shock tube and in the NOL 40-cm by 40-cm wind tunnel，should be developed. With this gage, answers to some of the many questions remaining from the previous tests (References 1 and 2) could be obtained. Primarily these questions involve scaling criteria, both with respect to the model configurations and with respect to the aerodynamic conditions.nIt is the purpose of this report to describe the development and testing of the new force gage and to present the characteristics of the gage insofar as these affect the presently-intended use of the gage for drag test purposes.
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