"The object of this investigation is to make available to the aircraft industry authoritative information on the strength, weight, and cost of a number of types of welded joints. This information will, also, assist the aeronautics branch in its work of licensing planes by providing data from which the strength of a given joint may be estimated. As very little material on the strength of aircraft welds has been published, it is believed that such tests made by a disinterested governmental laboratory should be of considerable value to the aircraft industry" (p. 323).

From Summary: "Additional tests of a 1/7-size model of the Grumman XJR2F-1 amphibian were made in Langley tank no. 1 to compare the behavior during take-off of the model equipped with split- and slotted-type flaps. The slotted flag had a large effect on locating the forward center-of-gravity limits for stable take-offs. Stable take-offs within the normal operating range of positions of the center of gravity could be made with the split flaps deflected 45 degrees or with the slotted flaps deflected less than 20 degrees."

Report presenting flight tests to determine the longitudinal stability and control characteristics of models of the Lark pilotless aircraft. Testing included the standard configuration with the horizontal wing flaps deflected 0 degrees, 15 degrees, and 60 degrees, and a test with the tail surfaces in line with the wings with the wing flaps not deflected. Results regarding time-history records, drag, longitudinal stability, and control effectiveness are provided.

Report presenting an investigation of the NACA 4-(4)(06)-057-45A and NACA 4-(4)(06)-057-45B two-blade swept propellers in the high-speed tunnel at blade angles of 25 degrees, 55 degrees, 60 degrees, 65 degrees, and 70 degrees. The swept propellers were compared with straight propellers and were found to be 10 percent more efficient at a forward Mach number of 0.85 for the design blade angle of 60 degrees. Results regarding the effect of forward Mach number, blade sweep, advance ratio, and constant power coefficient on efficiency are also provided.

Report discussing an investigation of the longitudinal trim and drag characteristics of two airplane configurations through the transonic speed range. One configuration had a thin straight wing and tail and one had a thicker 35 degree sweptback wing and a 46 degree sweptback tail on the same fuselage-fin arrangement. Information about the control effectiveness and stability and application to a full-scale airplane is also provided.

Report presenting a temperature survey made in the wake of two closely located parallel jets emerging into the atmosphere from two types of twin convergent nozzles. Results regarding the twin unshrouded nozzles and twin nozzles with twin geometry-simulated shrouds are provided.

From Introduction: "Presented in this paper are the results of an investigation of a semispan model of a delta wing with 60^o sweepback at the leading edge which was equipped with a large triangular control having an overhang balance mounted on a skewed hinge axis. The purpose of this investigation was to determine the aerodynamic characteristics of a delta wing with a control which was designed to provide aerodynamic balance at zero control deflection based on the span load distribution of reference 1."

From Introduction: "The wings were tested in combination with fuselage similar to the one used in the 7- by 10-foot wind-tunnel investigations. The results are reported herein and are compared with results for three similar model wings on the transonic bump (references 1, 2, and 3)."

Report presenting a direct-connect altitude test chamber investigation of the combustion performance of a 28-inch-diameter ramjet engine with a can-type center pilot burner. Combustion-chamber configurations with three different flame holders were investigated at a simulated flight Mach number of 2.0 and several different altitudes.

Report presenting an investigation in the 20-foot free-spinning tunnel to determine the motions and trim conditions from 0 to 90 degrees angle of attack for the X-3 airplane, which is a supersonic airplane with an extremely long nose and s mall wing. Testing was conducted on several scales of models and component parts. Results from dynamic and static tests are provided.

"The performance and operational characteristics of a Python turbine-propeller engine were investigated at simulated altitude conditions in the NACA Lewis altitude wind tunnel. In the performance phase, data were obtained over a range of engine speeds and exhaust nozzle areas at altitudes from 10,000 to 40,000 feet at a single cowl-inlet ram pressure ratio; independent control of engine speed and fuel flow was used to obtain a range of powers at each engine speed. Engine performance data obtained at a given altitude could not be used to predict performance accurately at other altitudes by use of the standard air pressure and temperature generalizing factors" (p. 1).

Report of theoretical values of performance parameters for liquid hydrogen and flourine as a rocket propellant for a wide range of fuel-oxidant and expansion ratios. Parameters computed include specific impulse, combustion-chamber temperature, nozzle-exit temperature, equilibrium composition, mean molecular weight, characteristic velocity, coefficient of thrust, ratio of nozzle-exit area to throat area, specific heat at constant pressure, coefficient of viscosity, and coefficient of thermal conductivity.

Theoretical values of performance parameters for liquid hydrogen and liquid fluorine as a rocket propellant were calculated on the assumption of equilibrium composition during the expansion process for a wide range of fuel-oxidant and expansion ratios. The parameters included were specific impulse, combustion-chamber temperature, nozzle-exit temperature, equilibrium composition, mean molecular weight, characteristic velocity, coefficient of thrust, ration of nozzle-exit area to throat area, specific heat at constant pressure, coefficient of viscosity, and coefficient of thermal conductivity. The maximum value of specific impulse was 364.6 pound-seconds per pound for a chamber pressure of 300 pounds per square inch absolute (20.41 atm) and an exit pressure of 1 atmosphere.

Report presenting testing of a wing with 0 degree sweepback of the 0.25-chord line in combination with a body of revolution at Mach numbers from 0.60 to 1.11 for angles of attack up to 24 degrees. Results regarding lift characteristics, pitching moment, drag characteristics, and lift-drag ratio are provided.