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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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At least 523 records · Page 29

All sources NASA NTRS DOE OSTI

NASA NTRS1975

Repair of major system elements on Skylab

In-flight maintenance, as conceived and pre-planned for the Skylab Mission, was limited to simple scheduled and unscheduled replacement tasks and minor contingency repairs. Failures during the mission dictated complicated and sophisticated repairs to major systems so that the mission could continue. These repairs include the release of a large structure that failed to deploy, the assembly and deployment of large mechanical devices, the installation and checkout of precision electronic equipment, troubleshooting and repair of precision electromechanical equipment and tapping into and recharging a cooling system. The Skylab experience proves conclusively that crewmen can, with adequate training, make major system repairs in space using standard or special tools.

Pace, R. E., Jr.↗

NASA NTRS1965

Postflight Evaluation of Atlas-Centaur AC-5 (Launched 2 March 1965)

The Atlas-Centaur AC-5 vehicle was launched from ETR Complex 36A on March 2., 1965 at 8:25.04 a.m. EST. Within about 1 second after launch the thrust of the Atlas booster engine decayed rapidly; the vehicle settled back on the launch pad and was quickly destroyed by fire and explosion. Considerable damage was sustained by the launch complex and its associated equipment. Loss of booster engine thrust was due to fuel depletion at the turbopump inlets, which is attributed to closure of the fuel prevalve or the staging valve. To preclude the recurrence of either of these fuel valving malfunctions, the following corrective action has been taken: The remote control actuator has been replaced by manual operation of the Atlas fuel prevalve; the internal passage dimensions in the staging valve have been increased to lessen the hydraulic load on the valve poppet. In addition to the Atlas fuel system malfunction, a failure in the power control circuitry of the Centaur guidance computer resulted in partial removal of power at umbilical ejection. To prevent such a guidance system failure on future flights some redundant circuitry has been eliminated and more rigorous checkout procedures have been adopted. No further anomalies were discovered in the telemetered data prior to the Atlas booster thrust decay. A prime objective of the AC-5 flight was to place a dynamic model of the Surveyor spacecraft in a simulated lunar transfer trajectory. An important facet of this problem is the demonstration of a launch-on-time capability in accordance with the proper Earth-moon relation. The window opening time was established at 8:25 a.m. EST; thus the actual launch occurred within 4 seconds of the planned time.

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NASA NTRS1975

Apollo experience report: Guidance and control systems. Lunar module stabilization and control system

A brief functional description of the Apollo lunar module stabilization and control subsystem is presented. Subsystem requirements definition, design, development, test results, and flight experiences are discussed. Detailed discussions are presented of problems encountered and the resulting corrective actions taken during the course of assembly-level testing, integrated vehicle checkout and test, and mission operations. Although the main experiences described are problem oriented, the subsystem has performed satisfactorily in flight.

Shelton, D. H.↗

NASA NTRS1975

HELIOS dual swept frequency radiometer

The HELIOS dual swept frequency radiometer, used in conjunction with a dipole antenna, was designed to measure electromagnetic radiation in space. An engineering prototype was fabricated and tested on the HELIOS spacecraft. Two prototypes and two flight units were fabricated and three of the four units were integrated into the HELIOS spacecraft. Two sets of ground support equipment were provided for checkout of the radiometer.

White, J. R.↗

NASA NTRS1975

Marking LANDSAT images with small mirror reflectors

Uniquely identifiable artificial landmarks were generated in LANDSAT imagery by making use of specular solar reflection from small, easily transportable mirrors. The results are impressive in well-registered color composite enlargements, where the mirror returns appear as bright white spots. The signatures are unique enough that returns can be readily located in the computer compatible tape records either manually or by machine search. As embodied in experiments to date, the system is entirely passive. Mirrors must be carefully positioned prior to each satellite pass, but the required angle calculations are simple enough to be made on a hand calculator and the required input data are easily available. Possible applications of the technique include providing site identification and geodetic control in remote regions of the earth, enhancement of small targets such as offshore oil derricks, providing atmospheric transmission data coincident with other LANDSAT experiments, and providing a nearly perfect optical point source for overall system checkout.

Evans, W. E.↗

NASA NTRS1976

Shuttle payload interface verification equipment study. Volume 1: Executive summary

A preliminary design analysis of a stand alone payload integration device (IVE) is provided that is capable of verifying payload compatibility in form, fit and function with the shuttle orbiter prior to on-line payload/orbiter operations. The IVE is a high fidelity replica of the orbiter payload accommodations capable of supporting payload functional checkout and mission simulation. A top level payload integration analysis developed detailed functional flow block diagrams of the payload integration process for the broad spectrum of P/L's and identified degree of orbiter data required by the payload user and potential applications of the IVE.

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NASA NTRS1976

Command decoder system

The production and testing of hardware design for use in evaluating shuttle instrumentation, data processing, and ground checkout operations are described. Changes incorporated to make improvements as a result of system testing are included.

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NASA NTRS1976

Expansion and improvements of the FORMA system for response and load analysis. Volume 1: Programming manual

Techniques are presented for the solution of structural dynamic systems on an electronic digital computer using FORMA (FORTRAN Matrix Analysis). FORMA is a library of subroutines coded in FORTRAN 4 for the efficient solution of structural dynamics problems. These subroutines are in the form of building blocks that can be put together to solve a large variety of structural dynamics problems. The obvious advantage of the building block approach is that programming and checkout time are limited to that required for putting the blocks together in the proper order.

Wohlen, R. L.↗

NASA NTRS1976

Experiment definition phase shuttle laboratory. LDRL-10.6 experiment

The work completed on the experiment definition phase of the shuttle laboratory LDRL 10.6 micrometers experiment from 27 September 1975 to 26 January 1976 was reported. This work included progress in the following areas: (1) optomechanical system: completion of detail drawings, completion of the beryllium subassembly, fabrication, checking, and weighing of approximately 95% of the detailed parts, dry film lubrication of the bearings and gears, and initiation of assembly of the gimbals; (2) optics: update of the detailed optical layout, receipt of nine mirrors and the pre-expander; (3) miscellaneous: delivery of draft material for the final report, completion of optical testing of the 10.6 micrometers receiver, and receipt, assembly, and checkout of NASA test console.

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NASA NTRS1975

Tracking subsystem test requirements survey

A survey of the test and checkout requirements of the tracking portion of the communications and tracking subsystem was performed to evaluate adequacy of planned tests and test requirement documents. Emphasis is placed on identifying test completeness, duplications, and omissions. Items that may save time, aid in testing, and present a more complete integrated test program are also noted. The results of this survey are summarized.

Orr, D. H.↗

NASA NTRS1975

Tug avionics system overview

The recently defined Tug avionics system takes maximum advantage of projected technology advances to attain: low system weight; power system capacity essentially independent of mission duration; sensors for rendezvous, docking, and navigation update; all attitude communications; onboard checkout and redundancy management; and modular fault tolerant computer control. The requirements, selection trades, and configurations are discussed for the major subsystems: data management, guidance navigation and control, communications, rendezvous and docking, and electrical power. The integrated avionics system and the interfaces with the payload, Shuttle and ground are described.

Raaberg, M. T.↗

NASA NTRS1975

Tug rendezvous and docking with a spacecraft - A remote manned approach

The development and use of a visual simulator for remote-manned rendezvous and docking utilizing frame-by-frame, slow-scan, low-light-level TV (LLLTV) was conceived and initiated in mid-1974. The effort was limited to modification, checkout, and validation of simulator hardware specific to this task, to the development of simulation (digital computer) software, and technical support to several rendezvous and docking simulation studies. Analysis and simulation has shown that LLLTV, such as would be required for satellite inspection, could provide a suitable acquisition sensor for a remote manned rendezvous/docking subsystem. A manned, remote simulation has demonstrated its feasibility during the terminal rendezvous and docking phases. Should this approach prove fully adequate in subsequent detailed simulation studies and tests, an order-of-magnitude cost savings can be obtained for early rendezvous and docking operations.

Hurley, M. J.↗

NASA NTRS1975

Large Space Telescope - Orbital crew EV maintenance operations

The paper shows that orbital EV maintenance by the crew has a tremendous impact on several areas of the program, including operations, Shuttle interfaces, support equipment rendezvous and berthing, checkout and verification, levels of servicing achievable, logistics and spares and scientific instruments in order to permit changeout and possible future refurbishment. To achieve on-orbit EV maintenance, such challenges as designing for suited-astronaut access to all subsystem equipment elements, minimization for contamination, handling of extremely sensitive instruments, development of translation techniques, and use of existing GFE and hardware must be faced early in the preliminary design and operations analysis phases. All studies to date indicate that on-orbit EV manned maintenance of the LST (Large Space Telescope) is not only feasible but can be designed to be readily within the capability of the EV functioning astronaut. Both 1-g and neutral buoyancy man-in-the-loop simulations further support this point.

Fisher, H. T.↗

NASA NTRS1976

Flight simulation testing equipment for composite material systems

A test program is discussed which aims at establishing the time-temperature-stress characteristics of several classes of high-temperature composite materials in order to determine their suitability for applications in supersonic cruise aircraft. Five advanced composite materials (a boron epoxy, a boron polyimide, a graphite epoxy, a graphite polyimide, and diffusion-bonded boron aluminum) are being evaluated using a flight-test simulator capable of long-term automatic testing based on random loading and realistic flight temperature profiles. The design, construction, and checkout of this simulator are described along with the digital load programmer, load magnitude controllers, the hydraulic pumping system, the heating and cooling systems, the control console, and the data recording system. Typical results for short-term tests performed at constant temperatures and accelerated load rates are presented in terms of a random-load spectrum and a wearout model.

Haskins, J. F.↗

NASA NTRS1976

Organizing for low cost space operations - Status and plans

Design features of the Space Transportation System (vehicle reuse, low cost expendable components, simple payload interfaces, standard support systems) must be matched by economical operational methods to achieve low operating and payload costs. Users will be responsible for their own payloads and will be charged according to the services they require. Efficient use of manpower, simple documentation, simplified test, checkout, and flight planning are firm goals, together with flexibility for quick response to varying user needs. Status of the Shuttle hardware, plans for establishing low cost procedures, and the policy for user charges are discussed.

Lee, C.↗

NASA NTRS1976

Crew safety

Crew safety in the manned spaceflight is usually associated with a small group for safety and quality assurance. Crew safety is actually an integral part of all program phases from conception through final implementation. Factors associated with improving safety at each phase of development are discussed. Topics discussed include design, manufacture, hardware/software checkout, management reviews, training and simulation, and data retrieval and analysis. Crew safety is best accomplished by flying a successful mission.

Slayton, D. K.↗

NASA NTRS1976

Payload specialist station study. Volume 2, part 1: Preliminary design document

The details of six tasks of the payload Specialist Station study are discussed: (1) derive payload control and display requirements; (2) perform functional analyses; (3) perform system synthesis; (4) perform trade studies; (5) perform preliminary design; and (6) provide data format. Functional analysis diagrams were developed for the study payloads. These diagrams presented the payload's functional activities flow based on the six mission phases established. These phases are: (1) launch, ascent, orbit insertion; (2) on-orbit checkout and activation; (3) on-orbit operation; (4) deployment/retrieval; (5) on-orbit deactivation; and (6) descent, landing, post-landing. To perform system synthesis the widest variety of available hardware and software, as individual pieces of equipment and as systems, was investigated. The intent was to synthesize a complete AFD system or systems which could accommodate the range of requirements identified for the study missions.

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NASA NTRS1976

Quality assurance plan for Solar Maximum Mission (SSM) Instruments electronic assembly - HRUV spectrometer/polarimeter

The quality assurance program demonstrates recognition of the quality aspects and an organized approach to achieve them. It ensures that quality requirements are determined and satisfied throughout all phases of contract performance, including preliminary and engineering design, development, fabrication, processing, assembly, inspection, test, checkout, packaging, shipping, storage, maintenance field use, flight preparations, flight operations and post-flight analysis, as applicable.

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