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Ground Noise Survey at a Proposed Submarine Test Facility on Lake Travis
We conducted a brief survey of ground noise at a proposed submarine test facility on Lake Travis, northwest of Austin, Texas. The purpose of the survey was to find out the nature and level of the background seismic noise on the bottom of the lake at the site where the proposed submarine test facility would be located. Because of its immediate availability, we used a seismograph designed to acquire seismic data at the ocean floor. The survey was requested by Prof. Thomas Griffy of the Physics Department and Applied Research Laboratory of the University. This report describes the field survey, the data analysis and the results.Applied Research Laboratory, University of Texas at AustinInstitute for Geophysic
Generation of long time creep data of refrac- tory alloys at elevated temperatures seventh quarterly report, 26 dec. 1964 - 26 mar. 1965
Ultrahigh vacuum creep data for tungsten, tungsten-25 per cent rhenium, TZM and TZC MOLYBDENUM alloys and AS-30 niobium allo
Generation of long time creep data of refractory alloys at elevated temperatures fifth quarterly report, 26 jun. - 26 sep. 1964
Creep testing data and machine reliability for high-temperature long-time tests on niobium, tungsten, and rhenium alloy
Inclusion of explicit thermal requirements in optimum structural design
A finite-element based procedure is described for obtaining minimum mass designs of structures subjected to combined thermal and mechanical loading and both strength and thermal constraints. The procedure is based on a mathematical programming method using the Sequence of Unconstrained Minimizations Technique (SUMT) in which design requirements are incorporated by an exterior penalty function. The procedure is limited to steady-state temperatures which are controlled by structural sizing only. The optimization procedure is demonstrated by the design of a structural wing box with both mechanical loading and external heating, subject to design constraints on stress, minimum gage, and temperature. The final design for these conditions is compared with a corresponding design in which temperature constraints are omitted
Simulation studies of STOL airplane operations in metropolitan downtown and airport air traffic control environments
The operating problems and equipment requirements for STOL airplanes in terminal area operations in simulated air traffic control (ATC) environments were studied. These studies consisted of Instrument Flight Rules (IFR) arrivals and departures in the New York area to and from a downtown STOL port, STOL runways at John F. Kennedy International Airport, or STOL runways at a hypothetical international airport. The studies were accomplished in real time by using a STOL airplane flight simulator. An experimental powered lift STOL airplane and two in-service airplanes having high aerodynamic lift (i.e., STOL) capability were used in the simulations
Terminal-area flight procedures and route design for supersonic transport New York-transatlantic operations
The results of an analytical investigation of two departure and arrival transition procedures between John F. Kennedy International Airport and projected North Atlantic track systems for supersonic transport (SST) operations are presented. The procedures studied were: (1) separated departure and arrival transition routes with departures made at supersonic speeds, and (2) superimposed departure and arrival routes with departures restricted to subsonic speed until the airplane is on the track system. For both procedures, transition routes with intercept angles of 30 deg to 90 deg to both six-and four-track systems were investigated. Track spacings of 30 and 60 nautical miles were studied
Bulk viscosity of a gas of neutrinos and coupled scalar particles, in the era of recombination
Bulk viscosity may serve to damp sound waves in a system of neutrinos coupled
to very light scalar particles, in the era after normal neutrino decoupling but
before recombination. We calculate the bulk viscosity parameter in a minimal
scheme involving the coupling of the two systems. We add some remarks on the
bulk viscosity of a system of fully ionized hydrogen plus photons.Comment: 6 pages, 4 figure
Operational limitations in flying noise- abatement approaches
Operational limitations in flying noise abatement approache
Deployment and performance characteristics of 1.5-meter supersonic attached inflatable decelerators
Attached-inflatable-decelerator (AID) canopies fabricated from lightweight Nomex cloth and tapes were deployed in a supersonic stream from the base of a 140 deg conical aeroshell. Characteristics of the deceleration system were obtained over a wide range of Mach number, dynamic pressure, and pitch angle. All models deployed rapidly by ram air and experienced only mild deployment shock loads. Steady-state drag coefficients as high as 1.3 were obtained in the supersonic stream and were relatively insensitive to Mach number, dynamic pressure, and pitch angle. All models were free of fluttering motion. Results also showed that the AID is aerodynamically more efficient without a burble fence in a supersonic stream. Though measured meridian-tape loads were higher than those predicted by theory, the ram-air deployment rates and steady-state drag coefficients were in good agreement with theory. These results indicate that the AID is a stable, efficient decelerator in a supersonic stream and its performance is readily predictable
A simulator study of the supersonic transport in the air traffic control system
Real time environment and control simulation of supersonic transport in air traffic control syste
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