Report presenting data on the thermal performance and the static pressure drop characteristics of two finned-type exhaust gas and air heat exchangers. One heater was constructed of copper and stainless steel while the other was constructed from aluminum alloy. The measured thermal outputs and static pressure drops are compared with predicted magnitudes.

Report presenting an investigation of the possibility of using internal cooling instead of fuel enrichment to suppress knock and to estimate the fuel savings that will result. Data from four different sources was examined and an analysis of the fuel consumption was conducted. Four different types of coolants were explored.

Report presenting an investigation to determine the permissible increase in engine power by using various internal coolants from the consideration of fuel knock and cylinder cooling. The internal coolants tested were water, 30-70 methyl alcohol-water volume percent mixture, 70-30 methyl alcohol-water volume percent mixture, methyl alcohol, and 80-20 ethyl alcohol-water volume percent mixture.

From Introduction: "The purpose of this report is to show that it is practical to apply a least-squares method to the correlation of engine-cooling data."

"Friction and heat-dissipation data are presented for use in determining the load-carrying capacity of 2- by 1.25-inch bearings with the following types of lining: copper-lead, lead-indium-coated silver, and lead-coated copper-lead. The tests were made in a four-bearing friction machine and covered operation with three clearances using three oils of different viscosity at three oil-inlet temperatures. Values are computed to indicate the safe loads at various speeds for bearings lined with each of the three types of material" (p. 1).

"Charts are presented for the calculation of the critical compressive stress - the stress at which local instability occurs - for idealized web- and T-stiffened panels, and examples of the use of the charts are given" (p. 1).

Report divided into two sections. One discusses a correction that must be applied to a heat meter when it is used at temperatures other than temperatures at which it was calibrated. The other section contains the results of an application of the two methods of correcting the heat-transfer rates for contact and heat-meter resistance to experimental data.

Report presenting tests to determine the thermal and pressure-drop performance and durability of a cross-flow, internally finned, tubular exhaust-heat exchanger. The test covered a range of exhaust-gas flows, cooling-air flows, and exhaust-gas temperatures.

Report presenting the results of a wind-tunnel investigation of propellers operating at negative thrust. Negative-thrust characteristics of two- and four-blade single propellers and four- and eight-blade dual propellers were determined. The results indicate that the constant-speed reversed-pitch propellers posses aerodynamic characteristics that should make them excellent aerodynamic brakes.