Demonstration, Qualification, and Airworthiness Certification of Structural Damage Sensing (SDS) Systems for Air Force Application

Structural Health Monitoring (SHM) sensor systems have gained much interest in the aerospace community as potentially enabling technologies for reducing maintenance costs while maintaining flight safety of aging structures. Many candidate SHM technologies are essentially damage detection systems, i.e. variations of well-established NDI methods such as ultrasonics, electro-magnetic (eddy current), and acoustic emission. Still others employ displacement detection such as strain-sensing and dynamic vibration sensing. Unfortunately, the path for transition onto United States Air Force (USAF) weapon systems is not well defined. Before SHM technologies can be qualified for fleet-wide usage, these systems must demonstrate their capability to meet performance requirements in terms of detection capability, reliability, and safety while and providing an economic benefit. Ultimately the qualification program must be sufficiently robust to support an airworthiness certification decision. This document provides guidance for the demonstration and qualification of permanently mounted damage detection systems intended for use on USAF aircraft. More specifically, this document will a) focus on applications where damage tolerance principles are used to manage structural integrity, b) propose a task-based approach for system qualification, and c) identify existing Air Force policies that define the path for modification management and obtaining airworthiness certification approval.