Force Tests of Concrete Practice Bombs M38A2 Practice Bomb AN-M43 G.P. 500LB. Bomb AN-M56 L.C. 4000LB. Bomb

This report covers model tests in the High Speed Water Tunnel and Polarized Light Flume of the Hydrodynamics Laboratory at the California Institute of Technology on the following aircraft bombs for use against land targets and surface targets on water Concrete Practice Bombs (a) with large fin box tail, (b) with small fin box tail (c) with drum type tail M38A2 Practice Bomb AN-M43 G.P. 500 lb. Bomb AN-M56 L.C. 4000 lb. Bomb The tests were authorized under Project OD 99. Tests were made on two-inch diameter models in the High Speed Water Tunnel to determine the hydrodynamic forces (drag, cross force, and moment) under steady state conditions. No tests were made to determine the damping forces The test results apply only to velocities below the velocity of sound. Tests were made 1n the Polarized Light Flume to give a visual indication of the streamline patterns in steady flight. A comparison is made of the results of the Water Tunnel tests with tests previously made on models of the same bombs at the Wright Field Wind Tunnel.