Report presenting testing of a cambered and twisted wing with constant-chord elevons with a slender fuselage to determine the longitudinal and lateral control from the elevons for a range of Mach numbers. Results regarding lift, drag, pitching-moment, and rolling-moment characteristics for various elevon deflections are provided.

From Summary: "An investigation was conducted in the combustor of a 3000-pound-thrust turbojet engine to determine the altitude performance characteristics of AN-F-58 fuels. Three fuels conforming to AN-F-58 specification were prepared in order to determine the influence of boiling-temperature range and aromatic content on altitude performance. The performance of the three AN-F-58 fuels was compared with the performance of AN-F-48 (grade 100/130) fuel in the range of simulated altitudes from 20,000 to 55,000 feet, corrected engine speeds from 6000 to 12,500 rpm, and flight Mach numbers of 0.2 and 0.6."

The following report discusses special shielded containers, called coffins, that are used for removing beam hole plugs from the reactor, transporting them to plug storage and inserting them therein. This report focuses on the handling of dummy and experimental beam hole plugs.

Report presenting a wind-tunnel investigation of a semispan pointed wing of aspect ratio 1.7 with 60 degree leading-edge sweepback and 30 degree trailing-edge sweepforward with a control surface. The purpose of the investigation was to determine the effectiveness of flap-type controls at transonic and supersonic speeds. Results regarding the wing characteristics and control-surface characteristics are provided.

This report discusses methods of producing aluminum nitrate for the Redox process. Large amounts of aluminum nitrate are consumed during the Redox process, so this report explores preparation of this material through the dissolution of hydrated aluminum oxide in nitric acid.

Report presenting an approximate method for calculating the interference pressure distribution at zero lift of a symmetrical sweptback wing mounted on a circular cylindrical body with the chord plane of the wing passing through the axis of the body. An example is provided using a circular cylindrical body and an untapered wing with 60 degrees of sweepback.

"Available information on gust structure, airplane reactions, and pertinent operating statistics has been examined. This report attempts to coordinate this information with reference to the prediction of gust loads on airplanes. The material covered represents research up to October 1947" (p. 807).

"An investigation has been conducted in the Langley 20-foot free-spinning tunnel of a 1/29-scale model of the Republic XF-91 airplane with a.conventional-tail arrangement installed. Previously, tests were made on the model with a vee tail installed. The erect spin and recovery characteristics of the model were determined for the normal loading with the wing installed at various amounts of incidence. The spin investigation also included inverted-spin tests, spin-recovery-parachute tests, tests with the center of gravity moved rearward, and tests with external fuel tanks added to the model" (p. 1).

Report presenting the results of lift, drag, and pitching-moment measurements on a model of the Douglas D-558-2 airplane at a range of angles of attack and Mach numbers. The model was also tested with two different sets of chordwise fences in order to investigate their effects on force and moment characteristics at high speeds.

From Summary: "A theoretical investigation of the velocity profiles for laminar mixing of a high-velocity stream with a region of fluid at rest has been made assuming that the Prandtl number is unity. A method which involves only quadratures is presented for calculating the velocity profile in the mixing layer for an arbitrary value of the free-stream Mach number. Detailed velocity profiles have been calculated for free-stream Mach numbers of 0, 1, 2, 3, and 5."

Tests were made to determine the loss in exhaust-jet thrust and engine power resulting from the insertion of an exhaust-gas-to-air heat exchanger in a jet-type exhaust stack of an aircraft engine. The thermal performance of the heat exchanger was also determined.

"In the present paper an analysis is made of the compressible-flow variations occurring in heat-exchanger passages. The results of the analysis describe the flow and heating characteristics for which specific flow passages can be treated as segments of generalized flow systems. The graphical representation of the flow variations in the generalized flow systems can then be utilized as working charts to determine directly the pressure changes occurring in any specific flow passage. On the basis of these results, working charts are constructed to handle the case of air heated at constant wall temperature under turbulent-flow conditions" (p. 1).

A wind tunnel investigation was conducted to determine the performance of a 4000-pound-thrust axial-flow turbojet engine with a high flow compressor. Pressure altitudes included 5000 to 40000 feet with ram pressure ratios from 1.00 to 1.82. Altitudes included 20000 to 40000 feet and ram pressure ratios from 1.09 to 1.75. A comparison is made between engine performance with high flow and low flow compressors.

Operating characteristics of the 11-stage 4000-pound-thrust axial-flow turbojet engine were determined. A standard compressor and a compressor with the blade angles of the rotor and stator blades increased 5 degrees to obtain greater air flow, were investigated.

Report presenting an investigation to study cowling-spinner combinations based on the NACA 1-series nose inlets and to obtain systemic data for one family of approximately ellipsoidal spinners. 11 of the spinners were also tested in various combinations with 9 NACA open-nose cowlings, which were also tested without spinners. Results regarding flow over spinners, internal flow, external flow over cowling, critical Mach number characteristics, envelope values, and cowling section are provided.

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 September 10, 1947 to September 15, 1947, are presented.

A finite-difference method previously presented for computing elastic stresses in rotating disks is extended to include the computation of the disk stresses when plastic flow and creep are considered. A finite-difference method is employed to eliminate numerical integration and to permit nontechnical personnel to make the calculations with a minimum of engineering supervision. Illustrative examples are included to facilitate explanation of the procedure by carrying out the computations on a typical gas-turbine disk through a complete running cycle. The results of the numerical examples presented indicate that plastic flow markedly alters the elastic-stress distribution.

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 16, 1947 to August 20, 1947 are presented.

Report presenting an investigation to obtain the pressure distribution over a sharp-nose body of revolution with a circular-arc profile and fineness ratio 6 at transonic speeds using the NACA wing-flow method. Results regarding the variation of pressure coefficient with Mach number, pressure distributions along the body axis, pressure drag, and effects of interference and horizontal gradient are provided.

From abstract: "The chemical analyses of graphite test bars obtained from National Carbon Company and the analyses performed by the Hanford Works Laboratories Division do not correlate significantly with the test pile results, nor do the chemical analyses obtained from National Carbon Company agree with those done in the Handford Works Laboratories. Chemical results obtained at Hanford on samples taken lengthwise from individual bars correlated significantly with the individual test pile results."

From Summary: "The results of an experimental investigation of an NACA submerged-air-inlet system on a 1/5-scale model of a fighter airplane are presented. Preliminary development tests were conducted to select the optimum entrance configuration. Duct-system total-pressure losses and pressure distributions over the lip and ramp of this air intake were obtained."

The variation of pressure distribution is calculated for a two-dimensional supersonic airfoil either experiencing a sudden angle-of-attack change or entering a sharp-edge gust. From these pressure distributions the indicial lift functions applicable to unsteady lift problems are determined for two cases. Results are presented which permit the determination of maximum increment in lift coefficient attained by an unrestrained airfoil during its flight through a gust. As an application of these results, the minimum altitude for safe flight through a specific gust is calculated for a particular supersonic wing of given strength and wing loading.

Compilation of the papers presented at a NACA conference on transonic airplane design, including stability and control and configurations with extreme sweep. From Introduction: "The purpose of this conference was to convey to those involved in the study of the aerodynamic problems of transonic aircraft these recent research results and to provide those attending an opportunity for discussion of the results."

From experience gained by NACA test pilots in flying at high subsonic Mach numbers and from interpretation of the data obtained, some general precautionary rules for test flying near sonic Mach numbers have been formulated. The reasons for these rules are discussed and observations are made with respect to the hazards arising from undesirable stability and control characteristics which have been noted in test flights of various airplanes. This paper, although written primarily for the attention of test pilots, contains general information of interest to those who are concerned with various phases of flight testing near sonic Mach numbers.