This report follows experiments on the acute effects of 200 kv X-ray treatments on chickens in a series of 200 animals exposed to doses of 2 r to 1200 r, with an additional 100 chickens.

Report presenting a wind tunnel investigation to determine the downwash angles, dynamic pressure loss, and wake width behind wings with sweep angles of 45, 30, and 0 degrees. Results indicated that the spanwise distribution of downwash was affected by sweep in a manner similar to span loading, increased toward the root by sweepforward and toward the tip by sweepback.

Tests were made in the Langley 7 by 10 foot tunnel on a model of a fighter-type airplane with external stores. The data obtained is presented and compared to flight-test results to determine the feasibility of estimating flight buffet Mach number from tunnel data.

Report presenting wind-tunnel testing of submerged air inlets on the fuselage of a scale model of a typical fighter-type airplane. The results are presented for ramp plan forms with parallel and with diverging walls and show the effect of the duct-entrance location, internal ducting efficiency, and deflectors.

Memorandum presenting wind-tunnel tests of a semispan model of an unswept wing of aspect ratio 4 and taper ratio 0.5 at Mach numbers up to 0.94 to determine its aerodynamic characteristics as influenced by Mach number, Reynolds number, and modification of the basic diamond profile by rounding the ridge. Lift, drag, and pitching-moment data are presented for a range of Reynolds and Mach numbers. The results indicated that no severe static-longitudinal-stability problems up to Mach number 0.94.

Memorandum presenting the results of measurements of gust and draft velocities within thunderstorms at a selected air field over a 5-day period. They are also compared to previous flights.

"In order to understand the operation and the interaction of jet-engine components during engine operation and to determine how component characteristics may be used to compute engine performance, a method to analyze and to estimate performance of such engines was devised and applied to the study of the characteristics of a research turbojet engine built for this investigation. An attempt was made to correlate turbine performance obtained from engine experiments with that obtained by the simpler procedure of separately calibrating the turbine with cold air as a driving fluid in order to investigate the applicability of component calibration. The system of analysis was also applied to prediction of the engine and component performance with assumed modifications of the burner and bearing characteristics, to prediction of component and engine operation during engine acceleration, and to estimates of the performance of the engine and the components when the exhaust gas was used to drive a power turbine" (p. 1).

This report follows investigations of fission fragments, as they contain charged nuclear high energy and contain a high excess of neutrons.

"Results are presented of an investigation in the Langley 19-foot pressure tunnel of the longitudinal characteristics of a semispan model wing having 37 degrees sweepback of the leading edge, an aspect ratio of 6, and NACA 641-212 airfoil section perpendicular to the 27-percent-chord line. Several types of stall-control devices including extensible round-nose leading-edge flaps, a leading-edge slat, and a drooped leading edge were investigated; partial- and full-span trailing-edge split and double slotted flaps were also tested. In addition, various combinations of the aforementioned leading- and trailing-edge flaps were investigated" (p. 1).

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from August 13, 1947 to August 15, 1947 are presented.

From Summary: "Two rocket-powered models representative of a fighter-type airplane were investigated in flight at Mach numbers up to 1.01 and 1.07 by the Langley Pilotless Aircraft Research Division at its testing station at Wallops Island, Va. These models incorporated an inverse-taper wing and a vee tail and were flown with controls undeflected and wing and stabilizer set at 0 deg incidence. Values of lateral acceleration, normal acceleration velocity, and drag were obtained by use of telemeters and a Doppler velocimeter radar unit."

The gust and draft velocities from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from June 2, 1947 to June 7, 1947, are presented.

Design data are presented for the graphical construction of two-dimensional sharp-edge-throat supersonic nozzles of minimum length for test-section Mach numbers from 1.20 to 10.00. The method of characteristics used in the design is briefly reviewed.

A preliminary investigation of an axial-flow gas turbine-propeller engine was conducted. Performance data were obtained for engine speeds from 8000 to 13,000 rpm and altitudes from 5000 to 35,000 feet and compressor inlet ram pressure ratios from 1.00 to 1.17.

Performance properties and operational characteristics of an axial-flow gas turbine-propeller engine were determined. Data are presented for a range of simulated altitudes from 5,000 to 35,0000 feet, compressor inlet- ram pressure ratios from 1.00 to 1.17, and engine speeds from 8000 to 13,000 rpm.

The gust and draft velocities evaluated from records of NACA instruments installed in P-61C airplanes participating in thunderstorm flights at Clinton County Army Air Field, Ohio, from May 13 to May 29, 1947 are presented.

From Introduction: "This paper presents the test data obtained for the NACA 10-(3) (08)-03R propeller blade which was one of the blades tested to determine the effects of shank design."

"An investigation was conducted in an altitude test chamber to determine the effects of inlet airflow distortion on the compressor steady-state and surge characteristics of a high-pressure ratio, axial-flow turbojet engine. Circumferential-type inlet flow distortions were investigated, which covered a range of distortion sector angles from 20 deg to 168 deg and distortion levels up to 22 percent. The presence of inlet airflow distortions at the compressor face resulted in a substantial increase in the local pressure ratio in the distorted region, primarily for the inlet stages" (p. 1).