Memorandum presenting a linear theoretical analysis of the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. It is shown that, with the antenna stabilized in space, the effect of component lags on the response is small, so that the speed of response is small, so that the speed of response can be made to approach closely that of the airframe alone.

Memorandum presenting a linear theoretical analysis made of the performance of three proportional navigation guidance systems installed in a given supersonic, variable-incidence, boost-glide, antiaircraft missile at Mach numbers of 2.7 and 1.3. Three guidance systems are compared on the basis of the maximum obtainable speed of response of the missile and guidance-system combination consistent with adequate stability. Results regarding the effect of method of positioning the radar antenna on the speed of response, effect of Mach number on response, and effect of networks are provided.

Memorandum presenting a comparison of the maximum speed of response that can be attained by three missile configurations, a variable-incidence-wing, a canard, and a tail-control, in combination with a particular proportional navigation guidance system. The configuration that allows the most rapid overall guidance-system response depends on the control-system characteristics. Results regarding the rate-only feedback and rate and normal acceleration feedback are provided.

Report presenting steady straight-and-level and steady turning tracking runs against an aerial target using an F-51H airplane equipped with a fixed optical sight and with various combinations of maneuvering stick-force and stick-deflection gradients. Results regarding aim wander, elevator movement, and stick-force variation for various test conditions are provided.

The possibility of overshooting the anticipated normal acceleration as a result of the artificial-feel characteristics of the F-89C airplane at a condition of minimum static stability was investigated analytically by means of an electronic simulator. Several methods of improving the stick-force characteristics were studied. It is shown that, due to the lag in build-up of the portion of the stick force introduced by the bobweight, it would be possible for excessive overshoots of normal acceleration to occur in abrupt maneuvers with reasonable assumed control movements. The addition of a transient stick force proportional to pitching acceleration (which leads the normal acceleration) to prevent this occurring would not be practical due to the introduction of an oscillatory mode to the stick-position response. A device to introduce a viscous damping force would Improve the stick-force characteristics so that normal acceleration overshoots would not be likely, and the variation of the maximum stick force in rapid pulse-type maneuvers with duration of the maneuver then would have a favorable trend.

Report presenting an investigation of the feasibility of modifying the transient portion of the stick force in abrupt maneuvers in order to eliminate inadvertent normal-acceleration overshoots. The modification consists of additional stick force proportional to a quantity which leads the normal acceleration. The characteristics introduced by the inclusion of the force were considered to be very desirable by pilots.

Report presenting an investigation of internal film cooling of the exhaust nozzle of a 1000-pound-thrust liquid ammonia liquid-oxygen rocket engine. With water as a coolant, approximately 16 percent of the total propellant and coolant flow was required to film-cool the entire nozzle and with anhydrous liquid ammonia, approximately 19 percent of the total flow was required. Results regarding the coolant results and performance results are provided.

A flight investigation in natural icing conditions was conducted to determine the effect of inlet ice formations on the performance of axial-flow turbojet engines. The results are presented for icing conditions ranging from a liquid-water content of 0.1 to 0.9 gram per cubic meter and water-droplet size from 10 to 27 microns at ambient-air temperature from 13 to 26 degrees F. The data show time histories of jet thrust, air flow, tail-pipe temperature, compressor efficiency, and icing parameters for each icing encounter. The effect of inlet-guide-vane icing was isolated and shown to account for approximately one-half the total reduction in performance caused by inlet icing.

From Introduction: "This report describes some measurements of these quantities obtained by crashing fighter aircraft under circumstances approximating those observed in service."

Drag tests at zero lift have been made at Mach numbers from 0.7 to approximately 0.95 in the high speed wind tunnel of the Institute of Aerodynamics, ETH, Zurich, on a group of untapered wings of aspect ratio 3.25, having sweep angles of 0 degree and 35 degrees. For each sweep angle, a series of geometrically similar models was tested at a constant Reynolds number to provide a verification of computed tunnel blocking corrections. Tests were also made for wings having thickness ratios of 0.09 and 0.12 and the results compared with results predicted by von Karman's similarity law.

"A method of analysis based on slender-wing theory is developed to investigate the characteristics in roll of slender cruciform wings and wing-body combinations. The method makes use of the conformal mapping processes of classical hydrodynamics which transform the region outside a circle and the region outside an arbitrary arrangement of line segments intersecting at the origin. The method of analysis may be utilized to solve other slender cruciform wing-body problems involving arbitrarily assigned boundary conditions" (p. 1).

Report presenting a theoretical approach to determine the lateral frequency response of a fighter airplane to side gusts and rolling gusts at a Mach number of 0.7 and an altitude of 30,000 feet. Frequency response and power spectral density were determined with the controls fixed and in combination with three different basic types of attitude autopilots.

Report presenting an investigation to measure the flying qualities of a high-performance personal-owner airplane to investigate the possible causes of instrument flying accidents with that type of aircraft. Testing indicated that the lack of aerodynamic stall warning and rapid roll-off at the stall could contribute to stall-spin accidents with high-performance personal-owner aircraft. Results regarding the handling qualities and the control under instrument flying conditions are provided.

Report presenting tests to investigate the use of a simple centering spring, which had no variation of force gradient with impact pressure, as an artificial feel device for the elevator control of a fighter airplane. Testing was conducted using a Chance Vought F4U-4B airplane equipped with power controls. Results regarding the force experienced and effects of the feel system are provided.

"By use of an approximate equation for the wave drag of slender bodies of revolution in a supersonic flow field, the optimum shapes of certain boattail bodies are determined for minimum wave drag. The properties of three specific families of bodies are determined, the first family consisting of bodies having a given length and base area and a contour passing through a prescribed point between the nose and base, the second family having fixed length, base area, and maximum area, and the third family having given length, volume, and base area. The method presented is easily generalized to determine minimum-wave-drag profile shapes which have contours that must pass through any prescribed number of points" (p. 1).

"An investigation of the nature of the flow field behind a rectangular circular-arc wing has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured using a weathercocking vane measurements. Theoretical calculations of the variation of both downwash and sidewash with angle of attack using Lagerstrom's superposition method have been made" (p. 1).

"An investigation of the nature of the flow field behind a rectangular wing of circular arc cross section has been conducted in the Langley 9-inch supersonic tunnel. Pitot- and static-pressure surveys covering a region of flow behind the wing have been made together with detailed pitot surveys throughout the region of the wake. In addition, the flow direction has been measured by means of a weathercocking vane. Theoretical calculations have been made to obtain the variation of both downwash and sidewash with angle of attack by using the superposition method of Lagerstrom, Graham, and Grosslight" (p. 1).

"The theory of turbulence reached its full growth at the end of the 19th century as a result of the work by Boussinesq and Reynolds. It then underwent a long period of stagnation which ended under the impulse given to it by the development of wind tunnels caused by the needs of aviation. Numerous researchers, attempted to put Reynolds' elementary statistical theory into a more precise form. During the war, some isolated scientists - von Weizsacker and Heisenberg in Germany, Kolmogoroff in Russia, Onsager in the U.S.A. - started a program of research. By a system of assumptions which make it possible to approach the structure of turbulence in well-defined limiting conditions quantitatively, they obtained a certain number of laws on the correlations and the spectrum. Since the late reports have improved the mathematical language of turbulence, it was deemed advisable to start with a detailed account of the mathematical methods applicable to turbulence, inspired at first by the work of the French school, above all for the basic principles, then the work of the foreigners, above all for the theory of the spectrum" (p. 1).

From Introduction: "The analysis of flight data in the present report is, to a large extent, based on analyses and information contained in references 1 and 2 for wing deflections, reference 3 for horizontal-tail parameters, reference 4 for airplane lift-curve slopes and angles of zero lift, and reference 5 for wing centers of pressure."

Report presenting an analysis of horizontal-tail loads on a flexible multi-engined jet-propelled swept-wing medium bomber to determine the tail lift-curve slope due to tail angle of attack, tail-lift curve slope due to elevator deflection, tail pitching-moment coefficient due to elevator deflection, downwash factor, and elevator effectiveness factor. The effect of the stabilizer, effects of elevator flexibility, and effects of wing stability are presented.

Buffet boundaries, buffeting-load increments for the stabilizers and elevators, and buffeting bending-moment increments for the stabilizers and wings as measured in gradual maneuvers for a jet-powered bomber airplane are presented. The buffeting-load increments were determined from strain-gage measurements at the roots or hinge supports of the various surfaces considered. The Mach numbers of the tests ranged from 0.19 to 0.78 at altitudes close to 30,000 feet. The predominant buffet frequencies were close to the natural frequencies of the structural components. The buffeting-load data, when extrapolated to low-altitude conditions, indicated loads on the elevators and stabilizers near the design limit loads. When the airplane was held in buffeting, the load increments were larger than when recovery was made immediately.

"The primary objectives of the present paper are to report the horizontal-tail-loads measurements for configuration B which have not previously been reported and to summarize the horizontal-tail-loads results obtained with both configurations. The manner in which the aerodynamic-loads data were analyzed to include structural temperature effects and fuselage flexibility effects constitutes an important part of the present paper" (p. 1).

An extensive investigation of the changes of the local and mean heat-transfer coefficients along the pipe length, and some results.

"The flow-field characteristics around a swept-wing airplane model at low subsonic speed are described, and the loads induced on a typical missile model while operating within these flow fields are presented. In addition, theoretical flow fields are compared with experiment and are used in first-order estimations of the resulting induced missile loads" (p. 1).