1984. Advanced Composite Weight Reduction on the MD-11 Aircraft

Paper

Abstract

In order to achieve the performance guarantee of the MD- II, the weight of the newest transport plays a significant role. More than 9,000 pounds of advanced composites have been used on the NM- II to satisfy the need to save structural weight. Percent weight saving ranges from 13.3% to 55.0%, with simple structures generally having higher percentage weight savings than complex structures. The successful DC-10 composite flight service evaluation program initiated in 1976 has shown that composites are durable and require minimum maintenance. The flight service evaluation program, in addition to the MD-80 composite components in revenue service, have given us the necessary confidence to use a great quantity of composites on the MD-11. A new design philosophy has been used in the MD-11 which puts greater emphasis on reliability, maintainability, durability, and producibility, even though this may result in some reduction of the weight savings. Unique design features, new fabrication methods, repair philosophy, and repair methods are discussed. The biggest challenge of composite designers has been to achieve a well balanced design meeting the conflicting requirements of weight, strength, cost, and durability, while maintaining the goal of least amount of compromise.