Redesigning for Simplicity and Economy
CompositesWorld.com (01/02/12) Black, Sara
Composites are well established as enabling materials on virtually every military aircraft. Emphasis has shifted to redesigning and optimizing parts already produced in lightweight composites, aiming to reduce cost and simplify manufacture. One recent example is an access panel on the U.S. military’s V-22 Osprey, originally designed as a typical cored sandwich, produced via hand layup using woven carbon/epoxy prepreg and an aramid honeycomb core. The materials and design, however, were made costly due to the time and touch labor during manufacture, as well as the need for replacement panels. This prompted V-22 program operators to seek an alternate approach. The access panel has been made over into a compression-molded part with integral ribs, reducing touch labor and allowing part integration while reducing manufacturing time. For the V-22 access panel, CCS used a high-performance aerospace-grade carbon/epoxy bulk molding compound (BMC) called MS-4H. In the redesign, part models were transmitted to CCS by Boeing Rotorcraft in CATIA format. CCS engineers worked with Boeing to design the new part structure for producibility in a compression molding process. A redesigned access panel is part of a large cost-reduction project initiated by the Bell/Boeing V-22 program team to minimize cost per flight hour.