Termination of shell burning of helium in solar-mass stars
He shell burning termination in solar mass stars evolution to white dwarf stage
Kutter, G. S.↗
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Results for “TERMINAL”
Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Factors affecting handling qualities of a lift- fan aircraft during steep terminal area approaches
Handling qualities of V/STOL research vehicles during steep terminal area approaches, discussing powered lift fan VTOL aircraft limitations and instrument landing approach
Gerdes, R. M.↗
Switched-mode adaptive terminal control for propulsive landing of nonlifting spacecraft
Switched mode adaptive terminal control for propulsive landing of nonlifting gravity turn ballistic vehicle under uncertain atmospheric conditions
Bejczy, A. K.↗
A technique for lifting entry and terminal phase system optimization for the 1975 Mars Viking lander
Lifting entry and terminal phase system optimization for 1975 Mars Viking lander, considering graphical tradeoff approach including design parameter and atmosphere model variations
French, C. E.↗
Improved silver-zinc battery-terminal seals
Development of battery terminal seal for sealing electrolyte for periods of three to five years is discussed. Operating conditions of battery are defined. Components of electrolyte seal and method of production are reported. Schematic diagrams of device are included.
Snider, W. E.↗
On optimal scheduling and air traffic control in the near terminal area
A scheme is proposed for automated air traffic control of landing aircraft in the vicinity of the airport. Each aircraft is put under the control of an airport-based computer as soon as it enters the near-terminal area (NTA). Scheduling is done immediately thereafter. The aircraft is given a flight plan which, if followed precisely, will lead it to the runway at a prespecified time. The geometry of the airspace in the NTA is chosen so that delays are executed far from the outer marker, and violations of minimum altitude and lateral separations are avoided. Finally, a solution to the velocity mix problem is proposed.
Sarris, A. H.↗
Study of automatic and manual terminal guidance and control systems for space shuttle vehicles. Volume 1: Sections 1 through 3
The results of a study to analyze, design, and evaluate guidance and control systems are presented that start at an altitude of about 100,000 feet and bring the unpowered space shuttle orbiters to a precision horizontal landing. The systems under consideration included fully automatic versions which involve no pilot participation as well as various manual configurations that provide combinations of displays and control augmentation which permit the pilot to control the vehicle to a successful landing. Two classes of vehicles were studied: the low cross range or straight-wing orbiter and the high cross range or delta-wing (delta body) orbiter. The recommended navigation, guidance and control system is shown to be compatible with realistic physical constraints that would exist in space shuttlecraft and to be consistent with the 1971 avionics equipment state of the art. Aircraft capable of aerodynamically simulating the various candidate space shuttlecraft in their unpowered, terminal area descent were investigated, and flight test recommendations, including system mechanizations, are made.
Osder, S.↗
Study of automatic and manual terminal guidance and control systems for space shuttle vehicles. Volume 2: Section 4 through appendix B
Guidance and control design studies that were performed for three specific space shuttle candidate vehicles are described. Three types of simulation were considered. The manual control investigations and pilot evaluations of the automatic system performance is presented. Recommendations for systems and equipment, both airborne and ground-based, necessary to flight test the guidance and control concepts for shuttlecraft terminal approach and landing are reported.
Osder, S.↗
Space shuttle orbiter handling quality criteria applicable to terminal area, approach, and landing
An analytical pilot-vehicle study was made to determine the performance criteria for the space shuttle vehicle. Specifications for the flying qualities of piloted aircraft were used for appropriate portions of the space shuttle mission. The handling qualities during the terminal phases of the space shuttle flight were simulated to develop the necessary criteria. Additional criteria required for conditions during the unpowered approach and landing trajectory portion of the flight are explained.
Hardy, G. H.↗
Procedure for potting electrical cable assembly terminations
Procedures for the safe cleaning and potting of cable assembly terminations are given. Data cover primer application and injection of the potting compound. Required safety precautions for the process are listed.
Williams, H. F.↗
An algorithm for terminal air traffic control
An area-navigation method for automatic control of aircraft arriving in a random fashion from the en-route centers to the near terminal area is proposed. Control is exercised by a ground computer that sequences and schedules the aircraft. Altitude segregation is used to separate aircraft in velocity classes. Merging of all aircraft occurs near the outer marker. The merging region is designed so that no near misses will occur if the aircraft follow the assigned trajectories.
Sarris, A. H.↗
Analysis of pilot warning indicator performance in terminal area traffic.
Three pilot warning indicator concepts for collision hazard avoidance are analyzed using computer fast-time simulation. A hazard measure is defined based on a 1/2-g maximum horizontal acceleration, a maximum climb or dive angle of 10 deg for each aircraft, and a 20-sec warning time, through escape completion. The traffic model is based on flight tracks recorded in the Atlanta terminal area over an 11 hr period during August 1967. The basic PWI concept studied alarms on range to flashing beacons mounted on intruder aircraft as a function of relative azimuth and elevation. The alarm-hazard epoch ratio is about 17/1 to maintain the missed-alarm rate below 10%. Beacon vignetting or range-rate discrimination are shown to reduce the false-alarm rate by about 75%.
Ruetenik, J. R.↗
Statistical analysis of several terminal area traffic collision hazard factors.
An 11 hr sample of air traffic, comprising 584 tracks recorded at Atlanta during peak periods of August 1967, is analyzed to examine the statistical characteristics of range-guard intrusions and airspace conflicts in a terminal area. The number of intrusions (of an imaginary 3-naut mile, 500-ft range guard surrounding each aircraft) and number of conflicts (of the projected airspace for two aircraft) for a track exhibit Poisson variations with track duration. The hourly rate of intrusions follows the gas model square-law variation with traffic density, but the hourly conflict rate, contrary to the gas model, decreases with greater traffic density.
Ruetenik, J. R.↗
Automated aircraft scheduling methods in the near terminal area.
A general scheduling algorithm for aircraft from terminal area entry to touchdown is developed. The method has the following novel features: (1) many speed classes of aircraft are considered and speed variations within classes and along portions of the flight path are permitted; (2) multiple paths are considered which may merge or diverge - the analysis is not restricted to a single runway nor to departures only; (3) landings are scheduled along conflict free flight paths in minimum time. The algorithm is currently being incorporated in a fast-time simulation of a STOL air traffic system.
Tobias, L.↗
Optimal horizontal guidance law for aircraft in the terminal area.
A complete nonlinear control law is derived for guiding an aircraft in minimum time from an arbitrary initial position and heading to a prescribed terminal position and heading in the horizontal plane. The solution is obtained with the aid of the maximum principle, and is implemented by constructing a digital-computer program for the resulting switching logic.
Pecsvaradi, T.↗
A thin film, high sensitivity, two terminal, semiconductor strain sensor.
A two terminal semiconductor strain sensor which makes use of an evaporated piezoelectric layer to modulate the forward current-voltage characteristics of a thin film diode is described. The physical mechanisms are discussed and compared to other types of semiconductor sensors. Application to the electromechanical design of ultraminiature pressure transducers is discussed.
Mallon, J. R.↗
An investigation of vehicle dependent aspects of terminal area ATC operation.
Description of a terminal area simulation which permits analysis and synthesis of current and advanced air traffic management system configurations including ground and airborne instrumentation and new and modified aircraft characteristics. Ground elements in the simulation include navigation aids, surveillance radars, communication links, air-route structuring, ATC procedures, airport geometries, and runway handling constraints. Airborne elements include traffic samples with individual aircraft performance and operating characteristics and aircraft navigation equipment. The simulation also contains algorithms for conflict detection, conflict resolution, sequencing and pilot-controller data links.
Britt, C. L., Jr.↗
Terminal-area STOL operating systems experiments program
Information which will aid in the choice by the U.S. Government and industry of system concepts, design criteria, operating procedures for STOL aircraft and STOL ports, STOL landing guidance systems, air traffic control systems, and airborne avionics and flight control systems. Ames has developed a terminal-area STOL operating systems experiments program which is a part of the joint DOT/NASA effort is discussed. The Ames operating systems experiments program, its objectives, the program approach, the program schedule, typical experiments, the research facilities to be used, and the program status are described.
Smith, D. W.↗