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Mckinney, L. W.

Publications and source records attributed to Mckinney, L. W..

National Transonic Facility status

The National Transonic Facility (NTF) was operational in a combined checkout and test mode for about 3 years. During this time there were many challenges associated with movement of mechanical components, operation of instrumentation systems, and drying of insulation in the cryogenic environment. Most of these challenges were met to date along with completion of a basic flow calibration and aerodynamic tests of a number of configurations. Some of the major challenges resulting from cryogenic environment are reviewed with regard to hardware systems and data quality. Reynolds number effects on several configurations are also discussed.

Mckinney, L. W.

Testing and checkout experiences in the National Transonic Facility since becoming operational

The U.S. National Transonic Facility, constructed by NASA to meet the national needs for High Reynolds Number Testing, has been operational in a checkout and test mode since the operational readiness review (ORR) in late 1984. During this time, there have been problems centered around the effect of large temperature excursions on the mechanical movement of large components, the reliable performance of instrumentation systems, and an unexpected moisture problem with dry insulation. The more significant efforts since the ORR are reviewed and NTF status concerning hardware, instrumentation and process controls systems, operating constraints imposed by the cryogenic environment, and data quality and process controls is summarized.

Bruce, W. E., Jr.

Operational experience with the National Transonic Facility

Construction of the National Transonic Facility was completed in September 1982. The checkout of all systems required about one year. The facility operated to the design point of 120 million Reynolds number based on a 0.25 meter chord at a Mach number of 1.0. Performance of all systems was basically as expected. Setup for the detailed aerodynamic calibration begins late in 1983, and the calibration is expected to be complete by the last quarter of 1984.

Mckinney, L. W.

Wind-Tunnel/Flight Correlation, 1981

Wind-tunnel/flight correlation activities are reviewed to assure maximum effectiveness of the early experimental programs of the National Transonic Facility (NTF). Topics included a status report of the NTF, the role of tunnel-to-tunnel correlation, a review of past flight correlation research and the resulting data base, the correlation potential of future flight vehicles, and an assessment of the role of computational fluid dynamics.

Mckinney, L. W.

Status of the national transonic facility

The National Transonic Facility at NASA Langley Research Center, scheduled for completion in July, 1982, is described with emphasis on model and instrumentation activities, calibration plans and some initial research plans. Performance capabilities include a Mach number range of 0.2-1.2, a pressure range of 1-9 atmospheres, and a temperature range of 77-350 K, which will produce a maximum Reynolds number of 120 million at a Mach number of 1.0, based on a 0.25 m chord. A comprehensive tunnel calibration program is planned, which will cover basic tunnel calibration, data qualities, and data comparisons with other facilites and flights.

Mckinney, L. W.

High Reynolds number research - 1980

The fundamental aerodynamic questions for which high Reynolds number experimental capability is required were examined. Potential experiments which maximize the research returns from the use of the National Transonic Facility (NTF) were outlined. Calibration plans were reviewed and the following topics were discussed: fluid dynamics; high lit; configuration aerodynamics; aeroelasticity and unsteady aerodynamics; wind tunnel/flight correlation; space vehicles; and theoretical aerodynamics

Mckinney, L. W.

Status and operational characteristics of the National Transonic Facility

The article discusses the development and capabilities of the National Transonic Facility which is planned for operation in 1981. The fan-drive, cryogenic-pressurized, closed-return facility will have operating parameters of: 0.1-1.2 Mach, 1-9 bars pressure, 78-340 K, 150 dB sound pressure, and plus or minus 0.001 rms turbulence intensity. These operating conditions have been selected on the basis of several current and future aircraft and space transportation systems. The facility will provide full-scale testing conditions for calculating subsonic drag, airloads, and stability and control information. Data for pre-test conditions, on-line information, and post-test analysis will be computer-processed.

Nicks, O. W.

The U.S. 2.5-Meter Cryogenic High Reynolds Number Tunnel

The U.S. 2.5-Meter Cryogenic High Reynolds Number Tunnel is a fan-driven transonic wind tunnel scheduled for operation in 1981. It will operate at Mach numbers from 0.1 to 1.2, stagnation pressures from 1 to 9 bars, and stagnation temperatures from 352 to 80 Kelvin. The maximum Reynolds number capability will be 120 million at a Mach number of 1.0 based on a reference length of 0.25 meter. This paper describes the basis for the conceptual approach, the engineering design including unique features, and the performance operating envelopes for the tunnel.

Howell, R. R.

The characteristics of the planned National Transonic Facility

The National Transonic Facility is a high Reynolds number transonic wind tunnel designed to satisfy the research and development needs of NASA, DOD, and industry. The facility design incorporates the cryogenic approach to achieving high Reynolds numbers with manageable model loads. By using temperature as a test variable, a unique capability to clearly separate aeroelastic, Reynolds number, and Mach number effects will be possible. This capability will open new horizons in transonic aerodynamic research. The tunnel design including unique features and operating envelopes is described. A brief overview of the general operating arrangement and the schedule for facility construction is presented.

Mckinney, L. W.

Effect of wing-mounted nacelles on a 42 deg swept supercritical wing configuration at near-sonic speeds

An investigation was made to assess the effect of wing-mounted nacelles on a supercritical wing configuration at near-sonic Mach numbers. The investigation was made by utilizing the Cornell Aeronautical Laboratory 8-foot transonic tunnel and covered a Mach number range from 0.90 to 0.99. Force data and pressure measurements at selected locations were obtained. The investigation with the nacelles on included the effect of spanwise location of the nacelle (semispan locations of 35 and 70 percent) and the effect of area ruling for the nacelles located at the 35 percent semispan station. Tests were also made with the outboard nacelle extended forward so that it was directly adjacent to the inboard nacelle location. These tests provided a direct assessment of the extent of the nacelle interference flow field in a lateral direction.

Mckinney, L. W.

Canard-wing lift interference related to maneuvering aircraft at subsonic speeds

An investigation was conducted at Mach numbers of 0.7 and 0.9 to determine the lift interference effect of canard location on wing planforms typical of maneuvering fighter configurations. The canard had an exposed area of 16.0 percent of the wing reference area and was located in the plane of the wing or in a position 18.5 percent of the wing mean geometric chord above the wing plane. In addition, the canard could be located at two longitudinal stations. Two different wing planforms were tested: one with a leading-edge sweep angle of 60 deg and the other with a leading-edge sweep angle of 44 deg. The results indicated that although downwash from the canard reduced the wing lift at angles of attack up to approximately 16 deg, the total lift was substantially greater with the canard on than with the canard off. At angles of attack above 16 deg, the canard delayed the wing stall. Changing canard deflection had essentially no effect on the total lift, since the additional lift generated by the canard deflection was lost on the wing due to an increased downwash at the wing from the canard.

Gloss, B. B.

Maneuver and buffet characteristics of fighter aircraft

Recent research efforts in the improvement of the maneuverability of fighter aircraft in the high-subsonic and transonic speed range are reviewed with emphasis on the factors affecting aerodynamic boundaries, such as maximum obtainable lift, buffet onset, pitchup, wing rock, and nose slice. The investigations were made using a general research configuration which encompassed a systematic matrix of wing-design parameters. These results illustrated the sensitivity of section and planform geometry to a selected design point. The incorporation of variable-geometry wing devices in the form of flaps or leading-edge slats was shown to provide controlled flow over a wide range of flight conditions and substantial improvements in maneuver capabilities. Additional studies indicated that the blending of a highly swept maneuver strake with an efficient, moderately swept wing offers a promising approach for improving maneuver characteristics at high angles of attack without excessive penalties in structural weight.

Ray, E. J.

Maneuver and buffet characteristics of fighter aircraft

The high subsonic and transonic characteristics of fighter aircraft and the factors affecting aerodynamic boundaries, such as maximum obtainable lift, buffet onset, pitchup, wing rock, and nose slice are discussed. Investigations were made using a general research configuration which encompassed a systematic matrix of wing design parameters. These results emphasized the sensitivity to section and planform geometry at the selected design point. The incorporation of variable-wing-geometry devices in the form of leading-edge slats or flaps was shown in a number of flight and wind-tunnel studies to provide controlled flow over a wide range of flight conditions and substantial improvements in maneuver capabilities. Additional studies indicated that the blending of a highly swept maneuver strake with an efficient moderately swept wing offers a promising approach for improving maneuver characteristics at high angles of attack without excessive penalties in structural weight.

Ray, E. J.