US Air Force Research Laboratory Perspective on Structural Health Monitoring in Support of Risk Management

Abstract

The US Air Force (USAF) and US Department of Defense has a long history of research and development in the exploration of on-board sensors being used for detection of damage in aircraft structures. Initial activities can be traced to the early 1980’s which led to an extensive on-aircraft assessment of acoustic emission based (i.e. “passive) sensor system. In the late 1990’s an effort was launched to revitalize the capability which cumulated in the “Hot Spots” program which explored the use of an ultrasonic guided wave (i.e. “active”) sensor system. Each of these programs encountered challenges that have hindered the use of these technologies on fixed-wing military aircraft. This paper briefly reviews these previous efforts, present current USAF Military Standards that define Structural Health Monitoring (SHM) for fixed wing aircraft, and provide a discussion of current and future concepts for research and development to resolve these challenges and enable eventual adaptation of SHM for fixed-wing applications. This will include a summary of current initiatives within the Materials and Manufacturing Directorate of AFRL and notional thoughts on potential projects for future developments required for this capability to be applied to fixed wing military aircraft.