Tests were conducted in Langley tank no. 2 on models of an unconventional flying-boat hull called a planing-tail hull to determine the effects on resistance of varying a number of afterbody parameters. The effects of varying length, width, and plan-form taper of the afterbody are presented. Tests were made with afterbodies of two widths, two lengths, and two tapers. In the tests the depth of step and the angle of afterbody keel were held constant.

The second part of a series of tests made in Langley tank no. 2 to determine the effect of varying design parameters of planing-tail hulls is presented. Results are given to show the effects on resistance characteristics of varying angle of afterbody keel, depth of step, and length of afterbody chine. The effect of varying the gross load is shown for one configuration. The resistance characteristics of planing-tail hulls are compared withthose of a conventional flying-boat hull. The forces on the forebody and afterbody of one configuration are compared with the forces on a conventional hull.

The Izod-impact strengths and flexural properties of several types of plastic laminates, which are either in use or have potential application in aircraft structures and parts, were determined at different temperatures in the range of -70 degrees to 200 degrees F.

An investigation was made to determine the aerodynamic characteristics of three planing-tail flying-boat hulls which differed only in the amount of step fairing. The hulls were derived by altering the step and afterbody of a conventional flying-boat hull having a transverse step.