Report presenting calculations of the dynamic lateral stability characteristics of a mock-up configuration of the Douglas X-3. The oscillations were found to be stable for all calculations investigated but would not meet the Air Force damping requirements for the majority of the conditions. The use of an autopilot was found to greatly improve oscillation damping.

Models of two types of high-speed surface craft were tested in Langley tank no. 1 to obtain rough-water data for an evaluation by the David Taylor .Model Basin of the relative merits of the designs. Time-history records were obtained of trim, rise, and normal acceleration at two points in the hulls for various speeds and two sizes of waves.

The take-off stability characteristics of a Consolidated Vultee Aircraft Corporation Skate 7 seaplane were determined in the Langley tank no. 2. Trim limits of stability, trim tracks, and elevator limits of stability are presented.

Memorandum presenting a two-dimensional wind-tunnel investigation of the effects of maximum-thickness location on fluctuating pressures and normal-force coefficients on 9-percent-thick airfoils, which indicated that for normal-force coefficients up to 0.6, the section variables had little effect on the pressure pulsations and root-mean-square normal-force-coefficient fluctuations. Results regarding pressure fluctuations and normal-force-coefficient fluctuations are provided.

Results are presented showing the effects of gap, elevator, nose shape, balance, cut-out, and tabs on the aerodynamic characteristics of a horizontal tail surface tested in the NACA full-scale tunnel.

An investigation to determine and correlate the experimental surface heat-transfer coefficients of finned cylinders with different air-stream cooling arrangements was conducted at the Langley Memorial Aeronautical Laboratory from 1932 to 1938. The investigation covered the determination of the effect of fin width, fin space, fin thickness, and cylinder diameter on the heat transfer. Wind-tunnel tests were made in the free air stream with and without baffles and also with various devices for creating a turbulent air stream. Tests were also made with blower.

This report presents the results of measurements of flow in the boundary layer of a 1/40-scale model of the U. S. Airship "Akron" (ZRS-4) made with the object of determining the boundary-layer thickness, the point of transition from laminar to the turbulent flow, and the velocity distribution in the boundary layer.