Engineering topics

Rawls, E. A.

Publications and source records attributed to Rawls, E. A..

4 records

NASA NTRS1984

Water impact laboratory and flight test results for the space shuttle solid rocket booster aft skirt

A series of water impact tests was conducted using full-scale segment representations of the Space Shuttle Solid Rocket Booster (SRB) aft skirt structure. The baseline reinforced structural design was tested as well as various alternative design concepts. A major portion of the test program consisted of evaluating foam as a load attenuation material. Applied pressures and response strains were measured for impact velocities from 40 feet per second (ft/s) to 110 ft/s. The structural configurations, test articles, test results, and flight results are described.

Kross, D. A.↗

NASA NTRS1983

Space Shuttle solid rocket booster initial water impact loads and dynamics - Analysis, tests, and flight experience

A series of scale model tests, finite element dynamic response analyses and full scale segment tests have been performed for purposes of developing design criteria for the initial water impact loading conditions applied to the internal stiffener rings located in the aft skirt portion of the Space Shuttle Solid Rocket Booster (SRB). In addition, flight experience has yielded information relative to structural reinforcement requirements. This paper discusses the test and analysis methods and summarizes significant results. It is noted that, although scale model test data are valuable for identifying trends, they have shortcomings concerning definition of full scale design loads criteria. Also, the frequently used static equivalent loads definition approach is not applicable for this type impact loading condition applied to an aft skirt type structure. Various types of ring structural fixes, including the addition of selected types of foam, are presented as well as associated full scale segment test results. Depending on the type and contour shape of the foam, reductions on applied pressures and peak measured strains over 50 percent are noted.

Kross, D. A.↗

NASA NTRS1982

Space shuttle solid rocket booster water entry cavity collapse loads

Solid rocket booster cavity collapse flight measurements included external pressures on the motor case and aft skirt, internal motor case pressures, accelerometers located in the forward skirt, mid-body area, and aft skirt, as well as strain gages located on the skin of the motor case. This flight data yielded applied pressure longitudinal and circumferential distributions which compare well with model test predictions. The internal motor case ullage pressure, which is below atmospheric due to the rapid cooling of the hot internal gas, was more severe (lower) than anticipated due to the ullage gas being hotter than predicted. The structural dynamic response characteristics were as expected. Structural ring and wall damage are detailed and are considered to be attributable to the direct application of cavity collapse pressure combined with the structurally destabilizing, low internal motor case pressure.

Keefe, R. T.↗

NASA NTRS1971

Space Shuttle: Static pressure distribution on Chrysler Corporation Space Division SERV booster configuration

A dual purpose test was conducted in the propulsion wind tunnel (PWT) to evaluate the performance of an aerospike engine, in the presence of a booster, and obtain forebody and base pressure distributions on the booster in which it is installed. The test item was a 2.5 percent scaled replica of the SERV booster employing a 5 percent spike length aerospike engine installed in the base region of the model. Cold flow air was used to simulate engine jet operation. Two booster configurations were investigated, one on which reentry aerospike engine thermal protection doors were installed, and another where the doors were removed. The data presented are representative of the latter configuration for a Mach number range of 0 to 1.25 at angles of attack of 0 and 8 degrees and 0 degrees angle of sideslip.

Price, E. A.↗