NTF model concept for the X-29A. Part 1: Requirements, guidelines, and design loads

A few Charpy samples containing a transverse EB weld at the V-notch location were produced. Three tensile specimens containing a transverse weld were also produced. These samples were tested at cryogenic temperatures. The welded Charpy samples resulted in average impact values of 20 ft-lb. This average value is as good as the NASA test samples with the base metal. The tensile specimens broke at slightly higher loads than had been calculated. The Charpy specimens did not come up to the prescribed level of 25 ft-lb. The results of the specimen tests are presented

Initial development of an ablative leading edge for the space shuttle orbiter

A state-of-the-art preliminary design for typical wing areas is developed. Seven medium-density ablators (with/without honeycomb, flown on Apollo, Prime, X15A2) are evaluated. The screening tests include: (1) leading-edge models sequentially subjected to ascent heating, cold soak, entry heating, post-entry pressure fluctuations, and touchdown shock, and (2) virgin/charred models subjected to bondline strains. Two honeycomb reinforced 30 pcf elastomeric ablators were selected. Roughness/recession degradation of low speed aerodynamics appears acceptable. The design, including attachments, substructure and joints, is presented