SBIR-STTR Award

The arresting system is a critical component to ensure mission readiness and pilot safety during landing operations on an aircraft carrier. The Advanced Arresting Gear (AAG) water twister is the most critical mechanical component for absorbing kinetic energy from landing aircraft and as such it is necessary to ensure its reliability and health status. Issues have previously been identified with the design of the new AAG technology, specifically with the water twister, which has led to delays for system delivery and increased cost. A man portable diagnostic tool is desired to accurately and reliably assess the health of the water twister, for which no inspection tools have yet proven reliable. This proposal describes an acoustic emission (AE) inspection solution which will allow for detection, localization, and classification of damage within both the rotor blades as well as the stator plates. AE technology has had great success in early damage detection in a wide variety of rotating machinery applications. New, patent-pending shear sensitive AE sensors will be used to distinguish and isolate water-borne noise sources. Detection will focus on both cracking and corrosion damage, and advanced algorithms will be used to precisely identify damage location within the water twister.

Benefit:
As a result of the proposed work, an AE system will be developed for inspection and monitoring of damage in the Advanced Arresting Gear (AAG) water twister. The use of both conventional and new shear sensitive sensors to distinguish between water-borne and structure-borne noise sources will be a new contribution to the field of AE testing. Advanced algorithms will be developed to allow localization of AE sources on the rotor blades even during rotation. Reliable, early detection of damage in the water twister will allow advanced notice and planning for maintenance operations. Additionally, an AE system will provide damage information earlier than the current vibration monitoring system. After successful development of an advanced AE inspection system for the AAG water twister, the technology will be transferred to other commercial applications with rotating components in a fluid-filled housing such as water turbines for power generation or fluid-filled gearboxes.

Keywords:
Acoustic Emission, Acoustic Emission, AAG Water Twister, structural health monitoring, non-destructive evaluation

The arresting system is a critical component to ensure mission readiness and pilot safety during landing operations on an aircraft carrier. The Advanced Arresting Gear (AAG) Water Twister is the most critical mechanical component for absorbing kinetic energy from landing aircraft and as such it is necessary to ensure its reliability and health status. Issues have previously been identified with the design of the new AAG technology, specifically with the Water Twister, which has led to delays for system delivery and increased cost. A man-portable diagnostic tool is desired to accurately and reliably assess the health of the Water Twister. This proposal describes continued development of a combined acoustic emission (AE) and ultrasonic testing (UT) inspection solution which will allow for detection, localization, and classification of damage within the Water Twister using exterior sensors to perform in-situ inspection without disassembly. Initial Phase I results show great promise for AE technology to detect and locate cracks on interior components and the housing and for UT technology to assess damage status in key hot-spot areas. This effort will result in a prototype hardware and software system which will assist the user in damage testing and assessment.

Benefit:
As a result of the proposed work, a combined AE and UT inspection system will be developed for inspection and monitoring of damage in the Advanced Arresting Gear (AAG) Water Twister. Conventional and new shear-sensitive sensors may be used to distinguish between water-borne and structure-borne noise sources, which will be a new contribution to the field of AE testing. Advanced algorithms will be developed to allow localization of AE sources on the rotor blades, even during rotation, and to automatically classify noise sources. Reliable, early detection of damage in the Water Twister will allow for advanced notice and planning for maintenance operations. Additionally, an AE system will provide damage information earlier than the current vibration monitoring system. After successful development of an advanced inspection system for the AAG Water Twister, the algorithms and custom analysis software will be applied to other commercial applications with rotating components in a fluid-filled housing, such as water turbines for power generation or fluid-filled gearboxes.

Keywords:
Acoustic Emission, non-destructive evaluation, AAG Water Twister, ultrasonic testing, structural health monitoring