Impact of Operational Issues on Design of Advanced Composite Structures for Army Helicopters

A review of Army helicopter service experience vividly demonstrates that operationally induced failures are the dominant cause of structures maintenance requirements. Furthermore, many of these induced events will most likely exist regardless of the materials or design approaches selected for future helicopters. Recognition of this situation dictates that careful consideration be given to the general damage tolerance and, repair requirements and limitations of proposed advanced (composite) structures. This paper reviews the Army's helicopter operational service history regarding structures externally induced damage and relates this knowledge to design considerations for future composite concepts. The potential problem of environmental effects on structures repairs is discussed along with the interrelationship of design/materials selection and logistic support. Finally, a review of an ATL ongoing R&D program to more fully assess the reliability, maintainability, and operational and support cost characteristics of candidate helicopter advanced structures concepts is provided.