Crashworthy design of helicopter composite airframe structuresThe crashworthy behavior of composite materials and generic structural elements is investigated. Cruciform structural elements are crushed in order to determine their energy absorption capability to rotorcraft crash-type loads, and quasi-static compression tests are conducted on a series of aluminum and composite cruciform elements. These elements are representative of keel beam and bulkhead intersections in the subfloor of rotorcraft. Various designs of 'trigger mechanisms' reducing initial peak failure loads and initiating stable crushing failure modes are considered. It is shown that a carbon-fiber-composite/aramid-fiber-composite hybrid element with a columnlike midsection behaves more like a well-designed tubular composite element. Specimens which fail primarily in bending are typical of structural components used in the upper and lower portions of rotorcraft airframes.
Document ID
19910060791
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Boitnott, Richard L. (NASA Langley Research Center; U.S. Army, Army Aviation Research and Technology Activity, Hampton VA, United States)
Kindervater, Christof (DLR, Institut fuer Bauweisen- und Konstruktionsforschung, Stuttgart Federal Republic of Germany, United States)