NASA Scientific and Technical Aerospace Reports

of no penetration as described in Section 3.3. 6) SSMOD_CE.WKS Determines the number and maximum size of perforations
expected in an aluminum bumper of a Space Station common module over its orbital lifetime as discussed in Section 3.3.
Derived from text
Ceramics; Composite Materials; Hypervelocity Impact; Impact Tests; Meteoroid Protection; Space Debris; Spacecraft
Shielding; Shock Loads; Orbital Velocity; Velocity Distribution; Spreadsheets
20040112017 NASA Glenn Research Center, Cleveland, OH, USA
Degradation of Spacecraft Materials
Dever, Joyce; Banks, Bruce; deGroh, Kim; Miller, Sharon; [2004]; 91 pp.; In English
Contract(s)/Grant(s): 22-319-20-E1; No Copyright; Avail: CASI; A05, Hardcopy
This chapter includes descriptions of specific space environmental threats to exterior spacecraft materials. The scope will
be confined to effects on exterior spacecraft surfaces, and will not, therefore, address environmental effects on interior
spacecraft systems, such as electronics. Space exposure studies and laboratory simulations of individual and combined space
environemntal threats will be summarized. A significant emphasis is placed on effects of Earth orbit environments, because
the majority of space missions have been flown in Earth orbits which have provided a significant amount of data on materials
effects. Issues associated with interpreting materials degradation results will be discussed, and deficiencies of ground testing
will be identified. Recommendations are provided on reducing or preventing space environmental degradation through
appropriate materials selection.
Author (revised)
Degradation; Spacecraft Structures; Earth Orbital Environments
20040112021 NASA Glenn Research Center, Cleveland, OH, USA
Leo Spacecraft Charging Design Guidelines: A Proposed NASA Standard
Hillard, G. B.; Ferguson, D. C.; [2004]; 4 pp.; In English; 42nd AIAAAerospace Sciences Meeting and Exhibit, 5-8 Jan. 2004,
Reno, NV, USA
Contract(s)/Grant(s): WBS 319-20-D1; No Copyright; Avail: CASI; A01, Hardcopy
Over the past decade, Low Earth Orbiting (LEO) spacecraft have gradually required ever-increasing power levels. As a
rule, this has been accomplished through the use of high voltage systems. Recent failures and anomalies on such spacecraft
have been traced to various design practices and materials choices related to the high voltage solar arrays. NASA Glenn has
studied these anomalies including plasma chamber testing on arrays similar to those that experienced difficulties on orbit.
Many others in the community have been involved in a comprehensive effort to understand the problems and to develop
practices to avoid them. The NASA Space Environments and Effects program, recognizing the timeliness of this effort,
commissioned and funded a design guidelines document intended to capture the current state of understanding. This document,
which was completed in the spring of 2003, has been submitted as a proposed NASA standard. We present here an overview
of this document and discuss the effort to develop it as a NASA standard.
Author
Low Earth Orbits; Spacecraft Charging; Standards; Aerospace Vehicles; Spacecraft Design; NASA Programs
20040112033 Ohio Univ., Athens, OH, USA
A Flight Control Approach for Small Reentry Vehicles
Bevacqoa, Tim; Adams, Tony; Zhu. J. Jim; Rao, P. Prabhakara; [2004]; 13 pp.; In English; AIAA Guidance, Navigation, and
Control Conference, 16-19 Aug. 2004, Providence, RI, USA; Original contains black and white illustrations
Contract(s)/Grant(s): NAS8-01098; Copyright; Avail: CASI; A03, Hardcopy
Flight control of small crew return vehicles during atmospheric reentry will be an important technology in any human
space flight mission undertaken in the future. The control system presented in this paper is applicable to small crew return
vehicles in which reaction control system (RCS) thrusters are the only actuators available for attitude control. The control
system consists of two modules: (i) the attitude controller using the trajectory linearization control (TLC) technique, and (ii)
the reaction control system (RCS) control allocation module using a dynamic table-lookup technique. This paper describes the
design and implementation of the TLC attitude control and the dynamic table-lookup RCS control allocation for nonimal flight
along with design verification test results.
Author
Flight Control; Linearization; Lifting Reentry Vehicles; Spacecraft Configurations; Aerospace Planes
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