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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 1,387 records · Page 77

Solid rocket motors for the Space Shuttle booster.

The evolution of the space shuttle booster system is reviewed from its initial concepts based on liquid-propellant reusable boosters to the final selection of recoverable, solid-fuel rocket motors. The rationale associated with each of the several major decisions in the evolution process is discussed. It is shown that the external tank orbiter configuration emerging from the latest studies takes maximum advantage of the solid rocket motor development experience and promises to be the optimum configuration for fulfilling the paramount shuttle program requirements of minimum total development risk within acceptable costs.

Odom, J. B.↗

Space Shuttle bipropellant RCS engine.

The requirements of the Space Shuttle bipropellant reaction control system engine technology contract and the scheduled contract effort are presented herein. The requirements included an engine concept scalable from 400 to 1100 lbf, with a 100 mission life employing N2O4/MMH propellants. Emphasis is placed on reusability and minimum post-flight servicing. The engine components are reviewed and their selection is supported by tradeoff analyses, thrust chamber firing test data, materials test data, and metallurgical evaluations. The materials test data indicate that the proposed silicide coated columbium chamber and uncoated columbium injector have the potential of meeting the mission life requirements. The engine valve trade studies resulted in the selection of a torque motor operated bipropellant valve configuration. Fuel vortex film cooling of the insulated chamber is described together with the fuel vortex film cooling scaling parameter and its verification by test data to a thrust level of 5500 lbf.

Sanscrainte, W.↗

Revolutionary implications of the space shuttle.

The space shuttle concept, generated to meet the stringent requirement for a low-cost transportation system for further exploration and utilization of space, is discussed. By virtue of being a recoverable and reusable delivery vehicle, the space shuttle will provide a substantial reduction in recurring expenses associated with expendable launch vehicles. With its generous volume capacity and weight capability, the shuttle will have a drastic impact on all payloads, regardless of their destination, and will be able to recover spacecraft on a cyclic basis in order to permit their updating and refurbishing for later reuse. The shuttle's maintenance responsibilities may also involve performing scheduled or unscheduled repairs of malfunctioning satellites, either in orbit or after landing. The impact of the space shuttle, as a research laboratory, on the method of space experimentation has even more far-reaching implications.

Von Braun, W.↗

Contamination damage avoidance concepts for propulsion feed system components.

The potential gain in the reliability of reusable long-term mission vehicles through the minimization of component damage due to the ingestion of particulate contamination by feed system components has been recognized by the NASA-LeRC and MDAC, and a program to investigate these problems has been completed. This investigation covered the determination of the cycle life of a typical 2-in. poppet type of shutoff valve in an uncontaminated GH2 environment and then compared this component performance with simulated operation with GN2 and LN2 containing controlled amounts of AL2O2 contaminant particles. The original valve design was tested for contamination damage tolerance characteristics under full flow and cyclic operating conditions, redesigned to improve the damage tolerance to contaminants and then retested. A second method of approach to damage tolerance control was investigated through the evaluation of various types of particulate separation devices. The study included various types of dynamic separators but did not cover conventional filter assemblies.

Endicott, D. L.↗

Nonstationary ascent wind analysis.

A statistical approach for computing launch vehicle response to inflight winds is presented. In the response analysis the zonal component of the ascent wind velocity is modeled as a nonstationary random process. Model parameters are computed by processing available measured wind data. Pertinent pitch plane response statistics are computed and their value in constructing fatigue load spectra for a reusable launch vehicle is demonstrated. A method for using the response statistics to estimate structural reliability is also discussed. The accuracy and the cost saving potential of the probabilistic structural dynamics approach are assessed by performing comparisons with digital simulation results.

Howell, L. J.↗

Space Shuttle response to atmospheric turbulence.

A fully reusable Space Shuttle configuration has been analyzed during ascent flight to determine its response to atmospheric turbulence. Propellant sloshing, gust penetration, and automatic control system effects were included. The steady-state aerodynamic method of Woodward was used to derive the generalized aerodynamic forces, using the standard quasi-steady assumption. Aerodynamic interference effects between adjacent wings and bodies were found to be significant, with symmetric responses generally higher than antisymmetric. The stability augmentation system tended to lower booster response while increasing orbiter response. Loads due to 9 m/s quasi-square-wave gusts were considerably higher than the 3 sigma random turbulence loads. The elastic portion of the response accounted for about 15% of the total wing load in the discrete gust analysis, while in the random case the elastic effect was small.

Huntington, R. G.↗

Low cost space.

It is pointed out that a contradiction between boundless space and limited resources has put the space program in the distressing position of cutting good and worthy projects from its activities during this decade. One approach to ameliorate the situation is to increase the productivity of space activities by greater utilization of the equipment developed for its projects. The Space Shuttle constitutes the first big step in that direction. The reusable character of the Shuttle orbiter will cut operational costs by permitting recovery and reuse of payload equipment through routine round-trip operations to space.

Tischler, A. O.↗

An international space transportation and service system.

An overview of the state of the art in international space transportation systems, covering current launch vehicles, the space shuttle system, and the related aspects of IR astronomy, space physics, and space biology. A phase-over from expendable vehicles to a shuttle-based reusable space transportation system is visualized in 1980.

Naugle, J. E.↗

The Space Tug mission role and program planning.

More than half of the planned payload programs require a velocity increment beyond that nominally provided by the Space Shuttle. The reusable Space Tug system can satisfy this placement requirement and, in addition, can provide other, vital operational services for payloads in the 1980s. To realize maximum operational and economic benefits, it is desired that an orbital propulsive stage such as the Space Tug be available concurrently with Space Shuttle initial operations. Potential tug missions, significant interfaces, system characteristics, and configuration alternatives are discussed in conjunction with salient program planning factors.

Schnyer, A. D.↗

A concept for Space Shuttle payload ground operations.

The functional elements of payload operations and support are discussed together with some of the features of the operational concept. The existence of clear and simple lines of responsibility and authority is an important factor in a simplification of the decision process. A high orbiter utilization rate is a key to the economic advantage of the reusable transportation system.

Mccoy, G.↗

Earth-orbit mission considerations and Space Tug requirements.

The reusable Space Tug is a major system planned to augment the Space Shuttle's capability to deliver, retrieve, and support automated payloads. The Space Tug will be designed to perform round-trip missions from low earth orbit to geosynchronous orbit. Space Tug goals and requirements are discussed together with the characteristics of the full capability Tug. The Tug is to be operated in an unmanned 'teleoperator' fashion. Details of potential teleoperator applications are considered, giving attention to related systems studies, candidate Tug mission applications, Tug 'end-effector' alternatives, technical issues associated with Tug payload retrieval, and Tug/payload accommodations.

Huber, W. G.↗

Miniature biaxial strain transducer

Transducer is completely reusable and permits relocation to alternate points to be accomplished quickly. Size permits measurements to be made simultaneously over small areas and yields outputs directly proportional to strains measured. Transducer verifies elastic modulus, Poisson's ratio, and principal strain axes on materials.

Hoffman, I. S.↗

Space shuttle RCS engine

The design of the space shuttle RCS engine has the primary objective of reusability with minimum servicing. Engine S/N FT-2A has successfully completed all ten environmental (salt water spray, sand and dust, vibration and humidity) and hot fire cycles with no change in engine performance (steady state or pulse mode).

Source record↗

Rocket engine bipropellant valve problems and current efforts

In developing the highly successful bipropellant valves for the Apollo primary propulsion engines, a variety of developmental problems were encountered and resolved. These problems and the new technology that is being pursued to eliminate or minimize these problems on the space shuttle orbital maneuvering engine are discussed. The space shuttle, being a reusable system, has new requirements of the valve. The potential effects of these requirements on valve design and potential solutions are also discussed.

Fries, J.↗

Catalysis study for space shuttle vehicle thermal protection systems

Experimental results on the problem of reducing aerodynamic heating on space shuttle orbiter surfaces are presented. Data include: (1) development of a laboratory flow reactor technique for measuring gamma sub O and gamma sub N on candidate materials at surfaces, T sub w, in the nominal range 1000 to 2000, (2) measurements of gamma sub O and gamma sub N above 1000 K for both the glass coating of a reusable surface insulation material and the siliconized surface of a reinforced pyrolyzed plastic material, (3) measurement of the ablation behavior of the coated RPP material at T sub w is greater than or equal to 2150 K, (4) X-ray photoelectron spectral studies of the chemical constituents on these surfaces before and after dissociated gas exposure, (5) scanning electron micrograph examination of as-received and reacted specimens, and (6) development and exploitation of a method of predicting the aerodynamic heating consquences of these gamma sub O(T sub w) and gamma sub N(T sub w) measurements for critical locations on a radiation cooled orbiter vehicle.

Breen, J.↗

Acquisition/expulsion system for earth orbital propulsion system study. Volume 5: Earth storable design

A comprehensive analysis and parametric design effort was conducted under the earth-storable phase of the program. Passive Acquisition/expulsion system concepts were evaluated for a reusable Orbital Maneuvering System (OMS) application. The passive surface tension technique for providing gas free liquid on demand was superior to other propellant acquisition methods. Systems using fine mesh screens can provide the requisite stability and satisfy OMS mission requirements. Both fine mesh screen liner and trap systems were given detailed consideration in the parametric design, and trap systems were selected for this particular application. These systems are compatible with the 100- to 500-manned mission reuse requirements.

Source record↗

Medical electronics: A need and a challenge

Space programs have led to the development of telemetry pills for diagnosis of diseases of the digestive tract, reusable X-ray image storage plates that require no chemical processing, and muscular augmentation systems for the handicapped. These examples, together with countless other examples of technological innovation that can be drawn from research and development programs supported by government funds, offer a potential opportunity to stimulate growth and to control rising costs in medical electronics.

Dimeoff, J.↗