Tape-Wrapped "Aeroshells" Cut Cost of Hypersonic Glide Vehicles

  • Published
  • By Dr. Vernon Bechel, AFRL,RXA
  • Materials and Manufacturing
WRIGHT-PATTERSON AIR FORCE BASE, Ohio --  The Air Force Research Laboratory (AFRL) has developed and demonstrated a new process by tape-wrapping large, unique-shaped carbon-carbon aircraft shells, or aeroshells. Aeroshells are formed into a lifting body shape called Hypersonic Glide Vehicles, which are used as the primary structural element and thermal protection for future weapon delivery systems. This is a key element of a Boost-Glide concept for conducting a Prompt Global Strike mission.

Hypersonic Glide Vehicles may allow delivery of conventional payloads over long distances. Demonstration of the tape-wrap process is a major step toward development of these vehicles. This material processing demonstration achieved a large reduction in the number of parts and the labor required, and the cost of the aeroshell.

Specialized materials such as carbon-carbon are required as primary structural and thermal protection elements to sustain the severe temperatures on the surface of Hypersonic Glide Vehicles during high-speed flight. AFRL partnered with ATK Aerospace Systems to successfully develop and demonstrate the tape-wrap process; the bulk of the research focused on the development of techniques necessary to properly build up the material from plies of uncured polymer composite and cure large, lifting body-shaped sections.

The successful demonstration of the tape-wrap process was a major achievement that resulted in a more than 10 times reduction in the part count for complex-shaped, enclosed carbon-carbon atmospheric re-entry bodies. It also reduced the cost per pound for aeroshells by 40 percent and reduced human touch labor by 50 percent versus current manufacturing processes. Researchers accomplished these gains while maintaining sufficient thermal and mechanical properties in key portions of the structure. This should allow for an extended hypersonic glide within the atmosphere while still being able to sustain the inertial and aerodynamic loads produced by high G evasive maneuvers. The material performed well in ground tests that simulated long duration hypersonic glide trajectories.

Additional tests of both coupon level material samples and a small aeroshell were supported by the Air Vehicles Directorate and included extended exposures in both NASA and Air Force high temperature, high Mach arc jet facilities. These tests were critical in determining whether the switch to materials produced with the new process would be able to meet projected flight loads and ablation requirements.