380 p refs (NASA-TN-D-5481) Avail: CFSTI CSCL 01A The model consisted of a semispan wing-propeller combination and half fuselage The tests were made for both up-at-the-tip modes of propeller rotation, with and without a leading edge slat and with and without fences. The tests consisted of the measurement of the wing surface pressures over a range of angles of attack from 5 to 80° for thrust coefficients of 0.90, 0.80, 0.60, and 0.30 for flap deflections at 0°, 20°, 40°. and 60° The data are presented in tabulated form with only a minimum of analysis. Author AIRCRAFT Includes fixed-wing airplanes, helicopters, gliders, balloons, ornithopters, etc; and specific types of complete aircraft (e.g., ground effect machines, STOL, and VTOL); flight tests; operating problems (e.g., sonic boom); safety and safety devices; economics; and stability and control. For basic research see: 01 Aerodynamics. For related information see also: 31 Space Vehicles; and 32 Structural Mechanics. A69-13367* AIRCRAFT WITHOUT WINGS. C. A. Syverts on (NASA, Ames Research Center, Moffett Field, Science Journal, vol. 4, Dec. 1968, p. 46-51. Discussion of the M2- F1 and M2- F2 wingless aircraft, which will enable astronauts to make their own landings at an airport of their own choice. These aircraft are of the lifting-body type, and the basic shape from which they were evolved was a cone. At modest cost, these vehicles are capable of reconciling the very different demands of hypersonic atmosphere entry and conventional airfield landing. It is suggested that the lifting body aircraft offers an attractive, proven alternative to purely ballistic manned capsules. F. R. L. Review of the presently known characteristics and possible future applications of flexible wings. Among the various flexible wings, the all-flexible wing is exciting much interest because for the same gross weight and steady sink speed it requires only 1/10 as much area as the conventional parachute. Stiffened high-performance flexible wings show promise of becoming economical, lightweight, rugged, stowable wings for cargo tow gliders, and a variety for sports gliders; they may also be useful in the recovery of boosters and hypersonic aircraft. Attempts to use stiffened flexible wings were not encouraging because a greater performance is needed than that provided by the rigid or inflated frame of wings of conical shape used. Wind-tunnel results show that the maximum lift-drag ratio of the single-keel wing is about 2-1/2 while that of the twin-keel wing is about 3. G.R. A69-14930 * TRAILING VORTEX HAZARD. William A. McGowan (NASA, Aeronautical Vehicles Div., Society of Automotive Engineers, Business Aircraft Meeting, Light aircraft that encounter the trailing vortex system generated by heavy transport aircraft can experience high roll rates, loss of altitude, and large structural loads. Envelopes of vortex system velocities, duration, and movement for various wind conditions have been determined. Specific operational procedures for the takeoff, landing, and en route phases of flight are suggested to enable the light aircraft pilot to avoid the wake turbulence of heavy aircraft. A69-15563. (Author) V/STOL SESSION INTRODUCTORY AND REVIEW PAPER. New York Academy of Sciences, Annals, vol. 154, Nov. 22, 1968, p. 843-855. 7 refs. Description of the basic characteristics of V/STOL aircraft with emphasis on propeller, ducted fan, and turbojet types. An illustration of the basic tradeoffs between hovering capability and cruising speed is given for the various V/STOL types. It is shown that the compound helicopter achieves higher speeds by unloading the rotor and using an additional means of propulsion for cruising flight. It is concluded that the various V/STOL types afford a wide range of capabilities to satisfy a variety of mission requirements and that at least two or three V/STOL types in addition to the helicopter will eventually see wide-spread operational use. A69-15568 * NASA RESEARCH ON FLEXIBLE WINGS. B.H. Francis M. Rogallo (NASA, Langley Research Center, Hampton, Va.). (New York Academy of Sciences, International Congress on Subsonic Aeronautics, New York, N. Y., Apr. 3-6, 1967.) New York Academy of Sciences, Annals, vol. 154, Nov. 22, 1968, P. 953-961. 16 refs. A69-15571 * LIFTING-BODY RESEARCH VEHICLES IN A LOW-SPEED FLIGHT TEST PROGRAM. John G. McTigue and Bertha M. Ryan (NASA, Flight Research (New York Academy of Sciences, International Congress on Subsonic Aeronautics, New York, N. Y., Apr. 3-6, 1967.) New York Academy of Sciences, Annals, vol. 154, Nov. 22, 1968, p. 1014-1032. Discussion of a multiphased flight study to determine the handling qualities of lifting-body entry vehicles. Although manned orbital experience with ballistic shapes has been successful, the recovery of such vehicles leaves much to be desired. The maneuverability footprint at the time of retrofire for the Mercury and Gemini vehicles is extremely limited in comparison to the larger footprint of a lifting body with a maximum hypersonic lift-to-drag ratio of 1 to 1.3. In addition, the lifting body would provide a horizontal landing capability on prepared landing sites anywhere within the continental U.S. on a single orbit. Predictions based on small-scale wind-tunnel data are not always satisfactory, while predictions based on data obtained in full-scale wind tunnels with the actual flight vehicles are closer to the flight data for low-speed conditions. Fourteen glide flights on the M2-F2 have shown that the longitudinal handling qualities are good. It is hoped that the use of lifting bodies for space missions can be recommended within two years. G.R. A69-18058 *# EXPERIENCE USING BALAKRISHNAN'S EPSILON TECHNIQUE Members, $1. 00; nonmembers, $1.50. A technique for computing optimum profiles is developed which differs from the classical gradient method in that a term representing the constraint of satisfying the equations of motion is included in the cost function to be minimized. Although the number of unknown independent functions is increased to include the state variables, the dimensionality of the gradient of the modified cost is greatly re THE DYNAMIC RESPONSE OF A FLEXIBLE ROTOR BLADE TO John F. Ward and William J. Snyder (NASA, Langley Research American Institute of Aeronautics and Astronautics and American Approximate analytical solution of the dynamic response of a flexible rotor blade to a radially moving force. The results are interpreted specifically in terms of helicopter rotor-blade vibration characteristics associated with tip-vortex impingement. These results indicate that low-frequency mode resonant amplification of repetitive impulse loadings can be encountered at moderate to high forward speeds on lifting rotor systems. The resonant conditions are encountered in sequence with increasing forward speed. For blades of conventional design, the resonant frequencies are encountered at noninteger multiples of rotor rotational speed. (Author) Note aircraft against a background of the original plans and goals. worthy results were obtained in aerospace piloting problems, in validation of ground research and developmental testing facilities, and in the study of heat transfer in the presence of complex flow fields. The ability of the X-15 system to fly out of the atmosphere for a few minutes of space flight, followed by a steep reentry, produced additional data of value to the space program. Considerable detailed research and development efforts in many areas were given impetus, new and unsuspected problems were identified, and new technology was developed in time for urgent but initially unforeseeable applications. F. R. L. A69-29702 * FLIGHT INVESTIGATION OF THE WING-ROTOR LIFT-SHARING CHARACTERISTICS OF A HINGELESS ROTOR COMPOUND HELI COPTER. Perry L. Deal and Julian L. Jenkins, Jr. (NASA, Langley Research Center, Hampton, Va.). Society of Experimental Test Pilots, Technical Review, vol. 9, no. 3, 1969, p. 78-85. Results of a NASA flight test program utilizing the Army/ Lockheed hingeless rotor compound aircraft to determine the liftsharing characteristics of the wing and rotor in both level and maneuvering flight. The data show that there is an inherent reduction in rotor lift as level flight airspeed is increased. speed tendencies could require constant attention during maneuvering F.R. L. flight. The rotor over A69-30369 * SONIC BOOMS - FUNDAMENTAL CHARACTERISTICS. IN: MAN IN HIS ENVIRONMENT; INSTITUTE OF ENVIRON- Mt. Prospect, Ill., Institute of Environmental Sciences, 1969, p. 185-188. Description of the nature of the aircraft-created pressure patterns which are responsible for the sound commonly referred to as the sonic boom. Experimental and theoretical studies dealing with the problem are reported. It is pointed out that analytic and wind-tunnel studies have also served in the establishment of aircraft design techniques for sonic-boom minimization. A69-22379 *# A COMPARISON OF NEWTON-RA PHSON AND OTHER METHODS Lawrence W. Taylor, Jr., Kenneth W. Iliff, and Bruce G. Powers A new technique of determining stability derivatives from flight data is formulated and compared with the simple equations, analog matching, least squares, and Shinbrot methods of analysis. It is shown that the new technique, termed Newton-Raphson, is superior to the others whether flight data or a statistical model is used. Although the new method uses the Newton-Raphson technique, it is also similar to quasi-linearization. The Newton-Raphson technique has been developed to enable the use of a priori (wind tunnel) information and to automatically adjust bias terms and initial conditions to compensate for errors. The technique has been successfully applied to the X-15, XB-70, F-111, and HL-10 vehicles and has application to many other system identification problems. A69-26872 * THE X-15 PROGRAM IN RETROSPECT. (Author) John V. Becker (NASA, Langley Research Center, Aero-Physics Raumfahrtforschung, vol. 13, Mar. -Apr. 1969, p. 45-53. 21 refs. Review of the principal results of 199 flights of the X-15 research A69-30480 *# G. R. THE POTENTIAL OF NUCLEAR POWER FOR HIGH-SPEED OCEANGOING AIR-CUSHION VEHICLES. Frank E. Rom and Albert F. Kascak (NASA, Lewis Research Center, Cleveland, Ohio). American Institute of Aeronautics and Astronautics, Advanced Marine Vehicles and Propulsion Meeting, 2nd, Seattle, Wash., May 21-23, 1969, Paper 69-416. 17 p. 11 refs. Members, $1.00; nonmembers, $1.50. Investigation of the performance potential of air cushion vehicles powered with nuclear power plants based on nuclear aircraft technology. It is shown that aircraft nuclear power plants would be more than ten times lighter than current nuclear marine power plants. Based on a simplified cost analysis, the nuclear air cushion vehicle can carry payloads at the rate of 2 to 5 cents per ton mile. The cargo carrying capacity and the cost of hauling cargo in terms of cents per mile is independent of the range. The unrefueled range for these vehicles is expected to be of the order of 1 to 2 million miles. B. H. A69-35639 * # A STEERABLE LANDING GEAR FOR VEHICLES WITH MAIN GEAR SKIDS. Upshur T. Joyner (NASA, Langley Research Center, Hampton, Va.). American Institute of Aeronautics and Astronautics, Aircraft Design and Operations Meeting, Los Angeles, Calif., July 14-16, 1969, Paper 69-790. 11 p. 8 refs. Members, $1.00; nonmembers, $1.50. Description of a proposed steering system for lifting body spacecraft, consisting of a freely castoring corotating wheel nose gear with an axle that can be tilted right or left under pilot control, and skids on the main gear. A prototype gear used in research has developed a maximum usable steer force, or side force, of about 500 Ib with an applied vertical load of 2000 lb. This amount of steer force is shown to be sufficient to prevent the HL-10 vehicle from leaving the side of a 150-ft-wide runway following touchdown on center line with a lateral drift rate of 25 ft per second. (Author) A69-35648 * # FUTURE TECHNOLOGY TRENDS IN AIRBREATHING PROPULSION. James F. Dugan, Jr. (NASA, Lewis Research Center, Propulsion Section, Cleveland, Ohio). American Institute of Aeronautics and Astronautics, Aircraft Design and Operations Meeting, Los Angeles, Calif., July 14-16, 1969, Paper 69-774. 11 p. 34 refs. Members, $1.00; nonmembers, $1.50. For subsonic jet transports, noise control is a very pressing problem. The means to control this noise at its source (the engine) are assessed. These include designing for high bypass ratio, lining the ducts with acoustic material, using resonators, choking the engine airflow in the inlet or compressor guide vanes, and rotor-stator blade spacing. Further advances in lower SFC and engine weight are forthcoming through higher turbine inlet temperature, higher bypass ratios, new fuels, and advanced materials. The current trends in turbine-blade cooling are discussed along with the use of blowing and suction techniques for achieving higher stage loading in compressors and turbines to reduce their size and weight. The propulsion systems for a possible nuclear-powered subsonic cargo aircraft are briefly reviewed. For V/STOL aircraft, a wide variety of propulsion systems are being evaluated in prototype aircraft. The major types and tradeoffs among engine weight, low fuel consumption, and noise are illustrated. The major trends in hypersonic airbreathing propulsion are in engines that operate in two or more modes and in supersonic combustion. (Author) A69-35649 # RECENT STUDIES ON EFFECTS OF RUNWAY GROOVING ON AIRPLANE OPERATIONS. Upshur T. Joyner, W. Pelham Phillips, and Thomas J. Yager (NASA, Langley Research Center, Hampton, Va.). American Institute of Aeronautics and Astronautics, Aircraft Design and Operations Meeting, Los Angeles, Calif., July 14-16, 1969, Paper 69-773. 15 p. 14 refs. Members, $1.00; nonmembers, $1.50. Runway grooving is a significant way of improving tire traction in adverse weather conditions, and this technique has been under study by NASA. Various groove patterns have been evaluated for wet traction; one of the better groove patterns (with grooves 1/4 in. wide and 1/4 in. deep on 1 in. centers) was installed on a research runway. Full-scale traction studies were made using a Convair 990A transport and an F-4D fighter aircraft. Braking traction values obtained on the wet grooved runway were substantially higher than those obtained on the wet ungrooved runway. The results from these investigations were used as the basis for calculations of the effects of grooving on aircraft landing field length and takeoff balanced field length under wet conditions. Grooving is shown to be very beneficial on both (American Institute of Aeronautics and Astronautics, Aerodynamic Deceleration Systems Conference, 2nd, El Centro, Calif., Sept. 23-25, 1968, Paper 68-934.) Journal of Spacecraft and Rockets, vol. 6, May 1969, p. 621-623. 16 refs. Results are summarized from the 13-flight test program designed to furnish data applicable to decelerators for use on Mars. During the series, deployment was initiated at Mach numbers between 1.15 and 3.16 in the altitude region of 122, 000 to 159, 000 ft. Two techniques were employed to achieve the test conditions, one using a rocket vehicle and the other a large helium-filled balloon. The rocket-launched tests were conducted to obtain basic information on the candidate types and the balloon-launched tests to investigate their deployment performance in the wake of a large aeroshell. Three parachute types with diameters from 30 to 85 ft and a 15-ftdiam Ballute were tested. Deployment characteristics and loadings, drag values, and stability characteristics are summarized. Effects of porosity, sterilization, and mortar-type deployments are discussed. A unique "post-reefing" system for minimization of descent time after the data period is described. (Author) A69-37154* # INFLUENCE OF DRAG ON THE MISSION PERFORMANCE OF HYPERSONIC AIRCRAFT. Lionel L. Levy, Jr. (NASA, Ames Research Center, Moffett Field, Calif.). Journal of Aircraft, vol. 6, July-Aug. 1969, p. 326-329. 6 refs. The variations of drag during the climb and cruise phases of representative hypersonic-cruise transport missions were examined in detail for several possible hypersonic aircraft to assess the influence of drag on mission performance. During cruise, the drag due to lift has the most influence on estimates of performance, independent of configuration and altitude. During climb, the dominant drag component depends on configuration and/or flight path. In some cases, the friction drag was estimated to be 20 to 40 per cent of the total, a percentage great enough so that erroneous estimates would significantly affect performance estimates. Increasing the cruise Mach number increases the drag due to lift during both climb and cruise, and decreasing the allowable sonic-boom overpressure increases the drag due to lift during climb. Significant gains in performance can be realized for reasonably small reductions in drag. In one case, it was found that the payload capacity could be increased from 187 to 231 passengers by reducing the total drag 10 per cent throughout the mission. (Author) (American Institute of Aeronautics and Astronautics, Aerodynamic Deceleration Systems Conference, 2nd, El Centro, Calif., Sept. 23-25, 1968, Paper 68-929.) Journal of Spacecraft and Rockets, vol. 6, June 1969, p. 654-660. 6 refs. An extensive research program encompassing both structural and aerodynamic disciplines has demonstrated the potentiality and workability of attached inflatable decelerators (AIDs) for supersonic application. An AID consists of an inflatable fabric afterbody attached to a payload which can be deployed at supersonic speeds to provide a sizable increase in drag. An analysis for the determination of constant tension (isotensoid) AID shapes and masses is presented, and results are given in the form of plots. Performance data obtained from both subsonic drop tests and supersonic windtunnel tests of models designed from the analysis are presented. The most significant results are those obtained in the AEDC 16-S propulsion wind tunnel on two 5-ft-diam models deployed at Mach numbers 2.2 and 3. Both models deployed successfully and experienced flutter-free flight. The internal pressure and total drag agreed well with values obtained from the analysis. (Author) A69-39413 * # DESIGN, DEVELOPMENT, AND FLIGHT TEST EXPERIENCE WITH LIFTING BODY STABILITY AUGMENTATION SYSTEMS. Ronald P. Kotfilia (Sperry Rand Corp., Phoenix, Ariz.) and Weneth D. Painter (NASA, Flight Research Center, Edwards, Calif.). American Institute of Aeronautics and Astronautics, Guidance, Control, and Flight Mechanics Conference, Princeton, N.J., Aug. 18-20, 1969, Paper 69-887. 13 p. 7 refs. Members, $1.00; nonmembers, $1.50. Description of the design and development of lifting body stability augmentation systems, and discussion of the ground test techniques that were used for their evaluation. Test criteria and procedures are established for various ground tests, such as frequency response, limit cycle, and structural resonance. Ground test results SECONDARY EXPERIMENT SPACE AVAILABLE ON BALLOON John C. McFall, Jr. (NASA, Langley Research Center, Applied Materials and Physics Div., Hampton, Va.). IN: EARTH OBSERVATIONS FROM BALLOONS; AMERICAN SOCIETY OF PHOTOGRAMMETRY, SYMPOSIUM, WASHING. TON, D.C., FEBRUARY 6, 7, 1969, PROCEEDINGS. (A69- Falls Church, Va., American Society of Photogrammetry, 1969, p. Provision of information to new experimenters on secondary payload space availability on balloon flights, indicating the steps to follow in obtaining use of this space. There are three launching agencies: the USAF, the National Center for Atmospheric Research (NCAR), and the USN. Experiments should be autonomous, and weigh around 30 lb. The procedure for obtaining "hitch-hike" space is outlined, and the names and addresses of representatives of the METEOROLOGICAL CONSIDERATIONS FOR TETHERED AGRICULTURAL AND FORESTRY APPLICATIONS OF BALLOONS. A. B. Park (U.S. Department of Agriculture, Washing- ton, D.C.), p. 19-27. (See A69-40805 22-34) BALLOON FLIGHTS TO TEST REMOTE SENSORS. A. P. Colvocoresses (U.S. Geological Survey, Washington, D.C.), p. 30-35. SECONDARY EXPERIMENT SPACE AVAILABLE ON BALLOON FLIGHTS-1969. J. C. McFall, Jr. (NASA, Langley Research Center, Hampton, Va.), p. 38-43. (See A69-40807 22-02) REPORT ON A TEST OF A HOT-AIR BALLOON AS A PLATFORM FOR MARINE OBSERVATIONS. R. R. Green, F. J. Hester, J. Rockwell, Jr. (U.S. Bureau of Commercial Fisheries, La Jolla, Calif.), and R. R. Whitney (U.S. Bureau of Sports Fisheries and Wildlife; Washington, University, Seattle, Wash.), p. 45-63. MONITORING WATER POLLUTION FROM AN AIRBORNE PLATFORM. J. I. Bregman (U.S. Department of the Interior, STATIONARY BALLOONS FOR USE IN THE BUREAU OF LAND MANAGEMENT. G. B. Torbert (U.S. Department of the Interior, Washington, D.C.), p. 81-90. TETHERED BALLOON FOR STUDY OF COASTAL DYNAMICS. C. J. Sonu (Louisiana State University, Baton Rouge, La.), p. 91-102. (See A69-40808 22-02) A SURVEY OF THE POTENTIAL OF BEAMED MICROWAVE POWER FOR BALLOONS. J. C. Graham (Raytheon Co., Sudbury, Mass.), p. 103-112. (See A69-40809 22-03) A UNIQUE APPROACH TO BALLOON STATION KEEPING. E. R. Bourke (Raytheon Co., Waltham, Mass.), p. 113. THE HOT AIR BALLOON AS AN OBSERVATIONAL PLAT- FORM. J. A. Winker (Raven Industries, Inc., Sioux Falls, S. Dak.), p. 115-127. (See A69-40810 22-02) ADVANCED BALLOON SYSTEMS AS PHOTOGRAPHIC PLATFORMS. R. S. Ross (Goodyear Aerospace Corp., Akron, Ohio), p. 129-154. (See A69-40811 22-02) THE CURRENT STATE OF THE ART OF PLASTIC BALLOONS. J. Nelson (Winzen Research, Inc., Minneapolis, Minn.), p. 155-161. (See A69-40812 22-02) PERFORMANCE CHARACTERISTICS OF A TETHERED BALLOON SYSTEM. M. N. Silbert (NASA, Wallops Station, Wallops PERFORMANCE CHARACTERISTICS OF A TETHERED BAL- Mendel N. Silbert (NASA, Wallops Station, Vehicle Analysis Section, IN: EARTH OBSERVATIONS FROM BALLOONS; AMERICAN SOCIETY OF PHOTOGRAMMETRY, SYMPOSIUM, WASHING- TON, D.C., FEBRUARY 6, 7, 1969, PROCEEDINGS. (A69- Falls Church, Va., American Society of Photogrammetry, 1969, p. Description of tests determining the aerostatic and aerodynamic characteristics of the Dart Vee balloon. The physical properties of four Dart Vee balloons (nominal volumes range from 250 to 750 cubic feet) are presented, and their flight characteristics are evaluated. Results of the aerostatic analysis indicate that, due to the permeability of the gas envelope to helium, the balloon experienced a complete loss of super pressure and a loss of approximately ten per cent of its initial usable free lift in a 24 hour period. The results of the aerodynamic analysis indicate that the Dart Vee balloon has a lift to drag ratio of approximately 1.5 and a stall angle of 16.5 degrees. The balloon exhibited a static lift of 7.5 pounds and an aerodynamic lift of 70 pounds measured just prior to an observed instability which A69-41127 FLIGHT SAFETY FOUNDATION, ANNUAL INTERNATIONAL Arlington, Va., Flight Safety Foundation, Inc., 1968. 249 p. (American Airlines, Inc., New York, N.Y.), p. 1-10. (See A69- RELIABILITY APPROACH TO AIRCRAFT SAFETY. I. OVERALL WORLD STATISTICS. W. W. Moss (Pan American PLANNING FOR THE SUPERSONIC FUTURE. O. Bakke |