"A principle formerly used in an instrument for cloud detection was further investigated to provide a simple and rapid means for measuring the liquid-water content of clouds at temperatures above and below freezing. The instrument consists of a small cylindrical element so operated at high surface temperatures that the impingement of cloud droplets creates a significant drop in the surface temperature. The instrument is sensitive to a wide range of liquid-water content and was calibrated at one set of fixed conditions against rotating multicylinder measurements. The limited conditions of the calibration Included an air temperature of 20 F, an air velocity of 175 miles per hour, and a surface temperature in clear air of 475 F" (p. 1).

Report presenting measurements made at transonic speeds by the freely-falling-body method to compare the drag of a rectangular plan-form airfoil of aspect ratio 7.6 with an NACA 65-006 airfoil section. Results regarding the velocity measurements, base-pressure measurements, and airfoil drag measurements are provided.

Report presenting an analysis of a series of wing-body combinations in the 8-foot high-speed tunnel. The paper presents the results of an investigation of a wing-fuselage combination with a wing of unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and an NACA 65A006 airfoil section. Results regarding force and moment characteristics and wake and downwash characteristics are provided.

Report presenting the damping-in-roll stability derivatives of a missile configuration and its components as determined experimentally and theoretically. The experimental damping derivative of the wing-body combination was found to be 67 percent of its theoretical value. Results are given for the wing-body combination, the tail-body combination, and the wing-tail-body combination.

"A method of measuring instantaneous flow rates of liquid propellants for rocket research is presented. The instrument investigated utilizes the principle of electromagnetic induction. An electromagnetic flowmeter was built, investigated, and satisfactorily placed in service to measure the rate of flow of an oxidant into a rocket" (p. 1).

Report presenting an investigation of two versions of a type of forward underslung scoop mounted on a pointed fuselage in the supersonic blowdown tunnel. The scoop entrances were in the shape of a 60 degree sector of an annulus, but the sides of one scoop were sweptback, while the others were unswept. Results regarding the shadowgraphs and surface-pressure distributions and total-pressure recovery are provided.

Report presenting tests of rocket-propelled models at transonic speeds to compare the zero-lift drags of 45 degree sweptback wings with and without solid nacelles at the wing tips. The wing drag coefficient was lowered at high subsonic and supersonic speeds when the aspect ratio was reduced from 6.0 to 3.55. Results regarding the favorability of the wing-tip nacelles and the force-break Mach number of the varying configurations are also provided.

A study investigated the effects of suction through porous leading-edge surfaces on the longitudinal aerodynamic characteristics of a 47.5 degree sweptback wing-fuselage configuration in the full-scale tunnel. The wing section normal to the quarter-chord line was NACA 64(sub 1)A112, the aspect ratio was 3.4, and the taper ratio was 0.51. Results regarding the basic wing characteristics and effect of area suction on the longitudinal characteristics are provided.

Report presenting an investigation to determine the performance of 17 cooling-air ejectors at primary-jet pressure ratios from 1 to 10, secondary pressure ratios to 4.0, and a temperature ratio of unity. Results regarding pumping characteristics, effect of spacing ratio on pumping, effect of diameter ratio on pumping, thrust characteristics, effect of spacing ratio on thrust, effect of diameter ratio on thrust, comparison of cylindrical and conical ejectors, comparison of performance with small model ejectors, and a comparison of performance with full-scale installation are provided.

Report presenting a determination of the combustion efficiency of gaseous hydrogen fuel in a ramjet engine in a connected-pipe test facility. Operating conditions simulated a range of Mach numbers and altitudes. Results regarding the effect of inlet parameters and design variables on combustion efficiencies, comparison between methods of determining efficiency, and ignition characteristics are provided.

Report presenting an investigation in the supersonic pressure tunnel to determine the effects of various vertical positions of a wing and horizontal tail on the static longitudinal aerodynamic characteristics of a trapezoidal wing model. Results regarding effect of wing vertical position and tail-on characteristics are provided.

Report discussing testing on a high-thrust turbojet engine capable of operation at high flight speeds. The report presents the overall performance and blade-element performance of the engine at a specified hub-tip radius ratio and specific weight flow of air.

Memorandum presenting an investigation in the supersonic pressure tunnel to determine the stability and control characteristics of two canard airplane configurations equipped with various sizes of canard control surfaces. Two wings of equal area but differing in plan form were provided. Results regarding longitudinal characteristics and lateral characteristics are provided.

Tests were conducted in calm water in Langley tank no. 2 and in calm and rough water at an outdoor catapult in order to determine the best way to make a forced landing of an Army A-26 airplane and to determine its probable ditching behavior. These tests were requested by the Air Materiel Command, Army Air Forces, in their letter of March 26, 1943, WEL:AW:50.

The teat results showed that with either of the three tail arrangements, the model usually spun in flat attitudes with oscillations about the lateral and longitudinal axes. In general, full reversal of the rudder pedals did not stop the spinning rotation. To make the model satisfactorily meet-the spin-recovery requirements it was found that installation of either a very large ventral fin (l7.9 square feet, full scale) below the tail or a somewhat smaller ventral fin and rudder (12.4 square feet, total . full-scale area) with a rudder throw of at least +/-22deg was required. Either a 21.3-foot tail parachute or a 6.4-foot wing-tip parachute (drag coefficient approximately 0.70) appears necessary as an emergency spin-recovery device during demonstration spins.