Search Results

Large space structures will be a key element of our future space activities. They will include spacecraft such as the planned Space Station and large antenna/reflector structures for communications and observations. These large structures will exceed 100 m in length or 30 m in diameter. Concepts for construction of these spacecraft on orbit and their materials of construction provide some unique research challenges. This paper will provide an overview of our research in space construction of large structures including erectable and deployable concepts. Also, an approach to automated, on-orbit construction will be presented. Materials research for space applications focuses on high stiffness, low expansion composite materials that provide adequate durability in the space environment. The status of these materials research activities will be discussed.

On December 1, 1984, the National Aeronautics and Space Administration (NASA) and the Federal Aviation Administration (FAA) conducted the first remotely-piloted air-to-ground crash test of a transport category aircraft. The Full-Scale Transport Controlled Impact Demonstration (CID) was the culmination of four years of effort by the two agencies. NASA and the FAA had many objectives during the joint planning and conduct of the Controlled Impact Demonstration. NASA's interest was primarily structural crashworthiness. The FAA's primary interest was the demonstration of an antimisting fuel additive's performance. Demonstration of improved crashworthy design features was a secondary objective for the FAA. This paper is a report on the NASA experiments conducted during the CID. A portion of the preliminary structural loads data was released to the public at a Government/Industry CID Workshop held April 10, 1985, at Langley Research Center, Hampton, Virginia.

Results are presented of an experimental and analytical study of the dynamic response to crash loadings of five different load-limiting subfloors for general aviation aircraft. These subfloors provide a high-strength structural floor platform to retain the seats and a crush-able zone to absorb energy and limit vertical loads. Experimental static load-deflection data and dynamic deceleration response data for the five subfloors indicated that the high-strength floor platform performed well in that structural integrity and residual strength was maintained throughout the loading cycle. The data also indicated that some of the subfloor crush zones were more effective than others in providing nearly constant load for a range of displacement. The analytical data was generated by characterizing the nonlinear crush zones of the subfloor with static load-deflection data and using the DYCAST nonlinear finite element computer program.