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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 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS1974

Apollo experience report: Manned thermal-vacuum testing of spacecraft

Manned thermal-vacuum tests of the Apollo spacecraft presented many first-time problems in the areas of test philosophy, operational concepts, and program implementation. The rationale used to resolve these problems is explained and examined critically in view of actual experience. The series of 12 tests involving 1517 hours of chamber operating time resulted in the disclosure of numerous equipment and procedural deficiencies of significance to the flight mission. Test experience and results in view of subsequent flight experience confirmed that thermal-vacuum testing of integrated manned spacecraft provides a feasible, cost-effective, and safe technique with which to obtain maximum confidence in spacecraft flight worthiness early in the program.

Mclane, J. C., Jr.↗
NASA NTRS1972

Apollo experience report: Mission planning for lunar module descent and ascent

The premission planning, the real-time situation, and the postflight analysis for the Apollo 11 lunar descent and ascent are described. A comparison between premission planning and actual results is included. A navigation correction capability, developed from Apollo 11 postflight analysis was used successfully on Apollo 12 to provide the first pinpoint landing. An experience summary, which illustrates typical problems encountered by the mission planners, is also included.

Bennett, F. V.↗
NASA NTRS1976

Apollo Experiment Report: Lunar-Sample Processing in the Lunar Receiving Laboratory High-Vacuum Complex

A high-vacuum complex composed of an atmospheric decontamination system, sample-processing chambers, storage chambers, and a transfer system was built to process and examine lunar material while maintaining quarantine status. Problems identified, equipment modifications, and procedure changes made for Apollo 11 and 12 sample processing are presented. The sample processing experiences indicate that only a few operating personnel are required to process the sample efficiently, safely, and rapidly in the high-vacuum complex. The high-vacuum complex was designed to handle the many contingencies, both quarantine and scientific, associated with handling an unknown entity such as the lunar sample. Lunar sample handling necessitated a complex system that could not respond rapidly to changing scientific requirements as the characteristics of the lunar sample were better defined. Although the complex successfully handled the processing of Apollo 11 and 12 lunar samples, the scientific requirement for vacuum samples was deleted after the Apollo 12 mission just as the vacuum system was reaching its full potential.

White, D. R.↗
NASA NTRS1972

Apollo experience report: Certification test program

A review of the Apollo spacecraft certification (qualification) test program is presented. The approach to devising the spectrum of dynamic and climatic environments, the formulation of test durations, and the relative significance of the formal certification test program compared with development testing and acceptance testing are reviewed. Management controls for the formulation of test requirements, test techniques, data review, and acceptance of test results are considered. Significant experience gained from the Apollo spacecraft certification test program which may be applicable to future manned spacecraft is presented.

Levine, J. H.↗
NASA NTRS1972

Apollo experience report: Processing of lunar samples in a sterile nitrogen atmosphere

A sterile nitrogen atmosphere processing cabinet line was installed in the Lunar Receiving Laboratory to process returned lunar samples with minimum organic contamination. Design and operation of the cabinet line were complicated by the requirement for biological sterilization and isolation, which necessitated extensive filtration, leak-checking, and system sterilization before use. Industrial techniques were applied to lunar sample processing to meet requirements for time-critical experiments while handling a large flow of samples.

Mcpherson, T. M.↗
NASA NTRS1997

Formal Methods of V&V of Partial Specifications: An Experience Report

This paper describes our work exploring the suitability of formal specification methods for independent verification and validation (IV&V) of software specifications for large, safety critical systems. An IV&V contractor often has to perform rapid analysis on incomplete specifications, with no control over how those specifications are represented. Lightweight formal methods show significant promise in this context, as they offer a way of uncovering major errors, without the burden of full proofs of correctness. We describe an experiment in the application of the method SCR. to testing for consistency properties of a partial model of requirements for Fault Detection Isolation and Recovery on the space station. We conclude that the insights gained from formalizing a specification is valuable, and it is the process of formalization, rather than the end product that is important. It was only necessary to build enough of the formal model to test the properties in which we were interested. Maintenance of fidelity between multiple representations of the same requirements (as they evolve) is still a problem, and deserves further study.

Easterbrook, Steve↗
NASA NTRS1972

Apollo experience report: Command and service module environmental control system

A comprehensive review is presented of the design philosophy of the Apollo environmental control system together with the development history of the total system and of selected components within the system. In particular, discussions are presented relative to the development history and to the problems associated with the equipment cooling coldplates, the evaporator and its electronic control system, and the space radiator system used for rejection of the spacecraft thermal loads. Apollo flight experience and operational difficulties associated with the spacecraft water system and the waste management system are discussed in detail to provide definition of the problem and the corrective action taken when applicable.

Samonski, F. H., Jr.↗
NASA NTRS1973

Apollo experience report: Command module crew-couch/restraint and load-attenuation systems

The Apollo command module crew-couch/restraint and load-attenuation system was required to support and restrain the crewman during mission phases and to limit the load imposed on the crewman during landing. Component designs evolved when requirements changed and tests were conducted. Advancement in the state of the art for energy-absorbing devices and changes in restraint philosophies for impact protection resulted from the efforts and experiences presented.

Drexel, R. E.↗
NASA NTRS1973

Apollo experience report: Ascent propulsion system

The development of the Apollo lunar module ascent propulsion subsystem is documented. The ascent propulsion subsystem was designed, built, and tested to provide propulsive power for launching the ascent stage of the lunar module from the surface of the moon into lunar orbit for rendezvous with the orbiting command and service module. Because total redundancy was prohibitive in this subsystem, special emphasis had to be placed on reliability in design with adequate demonstration short of an extensive flight-demonstration program. The significant technical problems encountered during all phases of the program are identified and the corrective actions are discussed. Based on this experience, several recommendations are made for any future program with similar subsystem requirements.

Humphries, C. E.↗
NASA NTRS1973

Apollo experience report: Evolution of the rendezvous-maneuver plan for the lunar-landing missions

The evolution of the nominal rendezvous-maneuver plan for the lunar landing missions is presented along with a summary of the significant development for the lunar module abort and rescue plan. A general discussion of the rendezvous dispersion analysis that was conducted in support of both the nominal and contingency rendezvous planning is included. Emphasis is placed on the technical developments from the early 1960's through the Apollo 15 mission (July to August 1971), but pertinent organizational factors also are discussed briefly. Recommendations for rendezvous planning for future programs relative to Apollo experience also are included.

Alexander, J. D.↗
NASA NTRS1972

Apollo experience report: Electronic systems test program accomplishments and results

A chronological record is presented of the Electronic Systems Test Program from its conception in May 1963 to December 1969. The original concept of the program, which was primarily a spacecraft/Manned Space Flight Network communications system compatibility and performance evaluation, is described. The evolution of these concepts to include various levels of test detail, as well as systems level design verification testing, is discussed. Actual implementation of these concepts is presented, and the facility to support the program is described. Test results are given, and significant contributions to the lunar landing mission are underlined. Plans for modifying the facility and the concepts, based on Apollo experience, are proposed.

Ohnesorge, T. E.↗
NASA NTRS1972

Apollo experience report: Lunar module display and control subsystem

The lunar module display and control subsystem equipment is described with emphasis on major problems and their solutions. Included in the discussion of each item is a description of what the item does and how the item is constructed. The development, hardware history, and testing for each item are also presented.

Farkas, A. J.↗
NASA NTRS1972

Apollo experience report: S-band system signal design and analysis

A description is given of the Apollo communications-system engineering-analysis effort that ensured the adequacy, performance, and interface compatibility of the unified S-band system elements for a successful lunar-landing mission. The evolution and conceptual design of the unified S-band system are briefly reviewed from a historical viewpoint. A comprehensive discussion of the unified S-band elements includes the salient design features of the system and serves as a basis for a better understanding of the design decisions and analyses. The significant design decisions concerning the Apollo communications-system signal design are discussed providing an insight into the role of systems analysis in arriving at the current configuration of the Apollo communications system. Analyses are presented concerning performance estimation (mathematical-model development through real-time mission support) and system deficiencies, modifications, and improvements.

Rosenberg, H. R.↗
NASA NTRS1972

Apollo experience report: Acceptance checkout equipment for the Apollo spacecraft

The acceptance checkout equipment for the Apollo spacecraft is described, and the history of the major equipment modifications that were required to meet the Apollo Program checkout requirements is traced. Some major problem areas are outlined, and a discussion of future checkout methods is included. The concept of the future checkout methods presented provides for an increase in test equipment standardization among NASA programs and among all testing phases within a program. The capability for increased automation and reduction in the test equipment inventory is provided in the proposed concept.

Burtzlaff, I. J.↗
NASA NTRS1972

Apollo experience report: Structural loads due to maneuvers of the command and service module/lunar module

Analyses were performed to determine the structural loads caused by maneuvers of the docked Apollo command and service module/lunar module (CSM/LM). Results of CSM/LM docked interface loads analyses and service-propulsion-system engine support structure load analyses are compared with the structural allowable loads of the CSM/LM docked interface and the service-propulsion-system engine thrust mount, respectively, for different phases of spaceflight operations. An analysis also was performed to investigate the loads that resulted from the failure case in which the LM descent propulsion system is started in the full-throttle position.

Rutkowski, M. J.↗
NASA NTRS1972

Apollo experience reports: Window contamination

The problem of window contamination in the Apollo command module is reviewed. All five command module windows were contaminated while in earth orbit on the first three manned Apollo flights. The contamination sources were identified and eliminated. Preflight testing of lunar module windows showed that no serious contamination should occur, and this conclusion was verified in subsequent manned flights. The command module window designs and materials are described, the window contamination sources are identified, and the inflight and chemical analyses of the contamination are outlined. The corrective actions that were taken are reviewed. For the lunar module, the window design and materials and the preflight and fight evaluations are described. Window design recommendations are made.

Leger, L. J.↗
NASA NTRS1972

Apollo experience report: Onboard navigational and alignment software

The onboard navigational and alignment routines used during the nonthrusting phases of an Apollo mission are discussed as to their limitations, and alternate approaches that have more desirable capabilities are presented. A more efficient procedure for solving Kepler's equation, which is used in the calculation of Kepler's problem and Lambert's problem is included, and a sixth-order predictor scheme with a Runge-Kutta starter is recommended for numerical integration. The extension of the rendezvous navigation state to include angle biases and the use of a fixed coordinate system is also evaluated.

Savely, R. T.↗