Decompression procedures for the safe ascent of aerospace personnel from ground level to altitude, supplement B Final report
Repetitive diving/flying decompression table for safe ascent to cabin pressure altitudes
Schreiner, H. R.↗
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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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Providing safe landing at high approach speeds for space shuttle
Safe space shuttle landing at high approach speeds using automatic landing system and drag chutes
Pruin, R. J.↗
Safe-arm initiator Patent
Electroexplosive safe-arm initiator using electric driven electromagnetic coils and magnets to align charge
Parker, L. C.↗
Fail-safe bidirectional valve driver
Cross-coupled diodes are added to commonly used bidirectional valve driver circuit to protect circuit and power supply. Circuit may be used in systems requiring fail-safe bidirectional valve operation, particularly in chemical- and petroleum-processing control systems and computer-controlled hydraulic or pneumatic systems.
Fujimoto, H.↗
Safe handling practices for electrostatic-sensitive devices
Review is detailed compilation of safe handling practices for Metal-Oxide Semiconductor (MOS) circuit elements and other devices that are susceptible to damage by electrostatic discharge. Article lists safety procedures for all aspects of handling and use of these components. Included are guidelines for setting up static-free work station and list of materials and equipment needed to maintain antistatic protection. Appendix gives vendors of these items.
Herring, L. L.↗
Modified pipe extension safely releases chain binders
Pipe, cut partly in half lengthwise, and cupped and notched at one end, safely releases tension in chain binders that cinch tiedown chains around truck loads. Device prevents binder-handle from being thrown violently during release.
Haw, D. W.↗
Experience with fluorine and its safe use as a propellant
The industrial and the propulsion experience with fluorine and its derivatives is surveyed. The hazardous qualities of fluorine and safe handling procedures for the substance are emphasized. Procedures which fulfill the safety requirements during ground operations for handling fluorinated propulsion systems are discussed. Procedures to be implemented for use onboard the Space Transportation System are included.
Bond, D. L.↗
The determination of nutritional requirements for Safe Haven Food Supply System (emergency/survival foods)
The Space Station Safe Haven Food System must sustain 8 crew members under emergency conditions for 45 days. Emergency Survival Foods are defined as a nutritionally balanced collection of high density food and beverages selected to provide for the survival of Space Station flight crews in contingency situations. Since storage volume is limited, the foods should be highly concentrated. A careful study of different research findings regarding starvation and calorie restricted diets indicates that a minimum nutritional need close to RDA is an important factor for sustaining an individual's life in a stressful environment. Fat, protein, and carbohydrates are 3 energy producing nutrients which play a vital role in the growth and maintenance process of human life. A lower intake of protein can minimize the water intake, but it causes a negative nitrogen balance and a lower performance level. Other macro and micro nutrients are also required for nutritional interrelationships to metabolize the other 3 nutrients to their optimum level. The various options for longer duration than 45 days are under investigation.
Ahmed, Selina↗
Recent advances in efficient long-life, eye-safe solid state and CO2 lasers for laser radar applications
The key problems in the development of eye-safe solid-state lasers are discussed, taking into account the energy transfer mechanisms between the complicated energy level manifolds of the Tm, Ho, Er ion dopants in hosts with decreasing crystal fields such as YAG or YLF. Optimization of energy transfer for efficient lasing through choice of dopant concentration, power density, crystal field and temperature is addressed. The tailoring of energy transfer times to provide efficient energy extraction for short pulses used in DIAL and Doppler lidar is considered. Recent advances in Pt/SnO2 oxide catalysts and other noble metal/metal oxide combinations for CO2 lasers are discussed. Emphasis is given to the dramatic effects of small quantities of H2O vapor for increasing the activity and lifetime of Pt/SnO2 catalysts and to increased lifetime operation with rare isotope (C-12)(O-18)2 lasing mixtures.
Hess, R. V.↗
How Safe Is Control Software
Paper examines issue of software safety. Presents four case histories of software-safety analysis. Concludes that, to be safe, software, for all practical purposes, must be free of errors. Backup systems still needed to prevent catastrophic software failures.
Dunn, William R.↗
Eye-safe coherent laser radar system at 2.1 microns using Tm,Ho:YAG lasers
An eye-safe pulsed coherent laser radar has been developed by using single-frequency Tm,Ho:YAG lasers and heterodyne detection. Returns from a mountainside located 145 km from the laser radar system and the measurement of wind velocity to ranges exceeding 20 km have been demonstrated with transmitted pulse energies of 22 mJ.
Henderson, Sammy W.↗
Comparison of eye-safe solid state laser DIAL with passive gas filter correlation measurements from aircraft and spacecraft
Differential Absorption Lidar (DIAL) using solid state Ti:sapphire lasers finds current application in the NASA/LASE Project for H2O vapor measurements in the approximately = 0.820 micron region for the lower and mid-troposphere and in potential future applications in planned measurements of the approximately = 0.940 micron region where both strong and weak absorption lines enables measurements throughout the troposphere and lower stratosphere. The challenge exists to perform measurements in the eye-safe greater than 1.5 micron region. A comparison between DIAL and passive Gas Filter Correlation Radiometer (GFCR) measurements is made. The essence of the differences in signal to noise ratio for DIAL and passive GFCR measurements is examined. The state of the art of lasers and optical parametric oscillators (OPO's) is discussed.
Hess, Robert V.↗
Fail-Safe Synchronizer For Power Supply
Fail-safe synchronizer feeds external synchronizing signal to switching power supply. When external synchronizing signal lost, it feeds signal from relaxation oscillator to power supply.
Katz, Richard B.↗
Improved inhalation technology for setting safe exposure levels for workplace chemicals
Threshold Limit Values recommended as allowable air concentrations of a chemical in the workplace are often based upon a no-observable-effect-level (NOEL) determined by experimental inhalation studies using rodents. A 'safe level' for human exposure must then be estimated by the use of generalized safety factors in attempts to extrapolate from experimental rodents to man. The recent development of chemical-specific physiologically-based toxicokinetics makes use of measured physiological, biochemical, and metabolic parameters to construct a validated model that is able to 'scale-up' rodent response data to predict the behavior of the chemical in man. This procedure is made possible by recent advances in personal computer software and the emergence of appropriate biological data, and provides an analytical tool for much more reliable risk evaluation and airborne chemical exposure level setting for humans.
Stuart, Bruce O.↗
The role of simulation in determining safe aircraft landing separation criteria
The role of flight simulation in determining safe aircraft landing separation criteria is reviewed and discussed. A broad conclusion is made that previous vortex-encounter simulations were useful for predicting the general response of an aircraft in the presence of trailing vortices and the type of separation criteria to emphasize. These simulations, however, were generally limited in scope and validation. Broad requirements for an accepted simulation methodology are presented. Key technological issues are addressed, including the addition of high-fidelity vortex models and aircraft/vortex interaction effects in the simulation, and validation of simulations with experimental data. Finally, results from a preliminary one-degree-of-freedom simulation are shown. These indicate that reduced landing spacings may be feasible and that current aircraft categorizations should be reviewed.
Stuever, Robert A.↗
Eye-safe visible wavelength lidar
Recent technological advances on several fronts offer the possibility for relatively low-cost, eye-safe visible-wavelength lidar systems for autonomous aerosol/environmental monitoring applications. Improved silicon photodiodes and avalanche photodiodes that have become available offer high-quantum-efficiency detection at very low dark counts (10 to 1000 count/s) and can be used in a photon counting mode for signal plus background and dark current photoelectron count rates of megahertz. The essential requirements and features of a possible lidar system that capitalizes on technical advances on several fronts are outlined. A baseline lidar system is suggested for monitoring tropospheric and stratospheric aerosols. Sensitivity to wavelength, background radiation, detector characteristics, and other system parameters is discussed for several simulated data sets.
Cooley, T. W.↗
A method of calculating the safe fatigue life of compact, highly-stressed components
This paper describes a method which has been developed for estimating the safe fatigue life of compact, highly-stressed and inaccessible components for aeroplanes and helicopters of the Royal Air Force. It is explained why the Design Requirements for British Military Aircraft do not favor the use of a damage-tolerance approach in these circumstances.
Cardick, Arthur W.↗
Review of Issues Associated with Safe Operation and Management of the Space Shuttle Program
At the request of the President of the United States through the Office of Science and Technology Policy (OSTP), the NASA Administrator tasked the Aerospace Safety Advisory Panel with the responsibility to identify and review issues associated with the safe operation and management of the Space Shuttle program arising from ongoing efforts to improve and streamline operations. These efforts include the consolidation of operations under a single Space Flight Operations Contract (SFOC), downsizing the Space Shuttle workforce and reducing costs of operations and management. The Panel formed five teams to address the potentially significant safety impacts of the seven specific topic areas listed in the study Terms of Reference. These areas were (in the order in which they are presented in this report): Maintenance of independent safety oversight; implementation plan for the transition of Shuttle program management to the Lead Center; communications among NASA Centers and Headquarters; transition plan for downsizing to anticipated workforce levels; implementation of a phased transition to a prime contractor for operations; Shuttle flight rate for Space Station assembly; and planned safety and performance upgrades for Space Station assembly. The study teams collected information through briefings, interviews, telephone conversations and from reviewing applicable documentation. These inputs were distilled by each team into observations and recommendations which were then reviewed by the entire Panel.
Johnstone, Paul M.↗