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Monta, W. J.

Publications and source records attributed to Monta, W. J..

18 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1983

Supersonic loads due to shuttle-orbiter/external-tank attachment structures

A large variety of tests were conducted during development of the Space Shuttle to determine the strength, fatigue, and thermal characteristics of the thermal-protection system of the orbiter. The research and analysis carried out to accurately define and simulate the flow characteristics immediately ahead of the external tank attachment structures are described. The highest known acoustic pressure loads occur in these regions and tests to insure the ability of the titles to withstand these acoustic loads, plus those due to pressure gradient, were thought necessary. First flight-critical wind tunnel tests were therefore conducted in the Langley 8-Foot Transonic Pressure Tunnel (8-Ft. TPT), which simulated the time histories of Shuttle ascent loads on tile arrays bonded to structures which accurately duplicated those of the Shuttle. The time-varying free stream conditions were provided by controlling the deflection angle history of diffuser spoiler flaps in an automated way. Time histories of the critical load parameters imposed on the tile arrays in the tunnel are compared with those expected in flight.

Edwards, C. L. W.↗
NASA NTRS1981

Description and calibration of the Langley unitary plan wind tunnel

The two test sections of the Langley Unitary Plan Wind Tunnel were calibrated over the operating Mach number range from 1.47 to 4.63. The results of the calibration are presented along with a a description of the facility and its operational capability. The calibrations include Mach number and flow angularity distributions in both test sections at selected Mach numbers and tunnel stagnation pressures. Calibration data are also presented on turbulence, test-section boundary layer characteristics, moisture effects, blockage, and stagnation-temperature distributions. The facility is described in detail including dimensions and capacities where appropriate, and example of special test capabilities are presented. The operating parameters are fully defined and the power consumption characteristics are discussed.

Jackson, C. M., Jr.↗
NASA NTRS1981

Control characteristics for wrap-around fins on cruise missiles configurations

This paper presents selected results of a panel loads study conducted as part of the final phase of an extensive investigation of an air-breathing missile concept employing wrap-around aerodynamic surfaces. Typical results for M = 2.36 are presented for the fin load results, plus a brief review of basic results of the previously reported tests. Vapor screen results are also discussed. The present results indicate that the fin load characteristics are nearly identical for planar and curved fins having the same projected planform and would permit the use of planar-surface predictions for supersonic speeds in the preliminary design stages of missiles employing wrap-around curved fins.

Sawyer, W. C.↗
NASA NTRS1980

Effect of conventional and square stores on the longitudinal aerodynamic characteristics of a fighter aircraft model at supersonic speeds

The effects of conventional and square stores on the longitudinal aerodynamic characteristics of a fighter aircraft configuration at Mach numbers of 1.6, 1.8, and 2.0 was investigated. Five conventional store configurations and six arrangements of a square store configuration were studied. All configurations of the stores produced small, positive increments in the pitching moment throughout the angle-of-attack range, but the configuration with area ruled wing tanks also had a slight decrease on stability at the higher angles of attack. There were some small changes in lift coefficient because of the addition of the stores, causing the drag increment to vary with the lift coefficient. As a result, there were corresponding changes in the increments of the maximum lift drag ratios. The store drag coefficient based on the cross sectional area of the stores ranged from a maximum of 1.1 for the configuration with three Maverick missiles to a minimum of about .040 for the two MK-84 bombs and the arrangements with four square stores touching or two square stores in tandem. Square stores located side by side yielded about 0.50 in the aft position compared to 0.74 in the forward position.

Monta, W. J.↗
NASA NTRS1978

Effects of stores on longitudinal aerodynamic characteristics of a fighter at supersonic speeds

Experimental investigations of single and twin stores representative of advanced, elliptical cross section missile concepts were made at Mach numbers from 1.60 to 2.16 to substantiate theoretically predicted results. The stores were mounted on the fuselage of a model representing a fighter configuration. Store base closure effects in the carriage condition were also obtained through tests with and without base closure fairings.

Dollyhigh, S. M.↗
NASA NTRS1977

Longitudinal aerodynamic characteristics at Mach 0.60 to 2.86 of a fighter configuration with strut braced wing

An investigation was made to determine the effects on longitudinal aerodynamic characteristics of utilizing struts to brace the wing to allow the wing thickness reduction on the LFAX-8 fighter configuration. Structural and load analysis indicated that the maximum airfoil thickness could be reduced from 4.5 to 3.1 percent with the strut brace concept. Wave drag theory indicated that reducing the wing maximum thickness from 4.5 percent to 3.1 percent would yield a significant reduction in zero-lift wave drag of about 28 percent at the design Mach number of 1.60. Strut arrangements designed and tested included, a single straight strut, a single swept strut, and a set of tandem straight struts. In addition, a wire of approximately the same cross sectional area replaced the single straight strut on one series of runs. The original LFAX-8 with the 4.5-percent-thick wing was retested to serve as a base line for this investigation.

Dollyhigh, S. M.↗
NASA NTRS1973

Effect of reaction control system jet-flow field interactions on a 0.015 scale model space shuttle orbiter aerodynamic characteristics

The effects of the reaction control system (RCS) jet-flow field interactions on the space shuttle orbiter system during entry are discussed. The primary objective of the test program was to obtain data for the shuttle orbiter configuration to determine control amplification factors resulting from jet interaction between the RCS plumes and the external flow over the vehicle. A secondary objective was to provide data for comparison and improvement of analytic jet interaction prediction techniques. The test program was divided into two phases; (1) force and moment measurements were made with and without RCS blowing, investigating environment parameters (R sub e, Alpha, Beta), RCS plume parameters (Jet pressure ratio, momentum ratio and thrust level), and geometry parameters (RCS pod locations) on the orbiter model, (2) oil flow visualization tests were conducted on a dummy balance at the end of the test.

Monta, W. J.↗