Landing Gear Strut Operational Readiness Monitoring

ABSTRACT:Landing gear systems are one of the more problematic subsystems on USAF aircraft. The most common landing gear failures are caused by mis-servicing of the OLEO-pneumatic landing gear shock strut, resulting in transmission of much higher loads to the airframe structure (even for a "normal" landing events or cause excessive fatigue damage than originally assumed). This phenomena is present and problematic for multiple aircraft platforms. The ability to measure, record, and alert maintainers and crew of the condition of the landing gear shock strut without physical inspection would significantly reduce the maintenance burden, while supporting readiness objectives. The information would also allow USAF to make more intelligent management decisions about operational limits, inspection intervals, removal intervals, and depot overhaul cycle values. ES3 proposes to address strut improper servicing issues through the use of a stand alone, self powered, on-aircraft, miniaturized STrut Operational Readiness Monitoring (STORM) system. The STORM system will have the ability to process and store captured data, and use programmed logic to detect improper servicing and alert operators to a problematic landing gear without physical inspection via wireless transmission. The Phase I effort successfully determined the technical feasibility of developing a multi-function STORM system to assess the shock strut critical readiness parameters (fluid level, pressure, and temperature). Technology readiness was advanced via component and breadboard testing in a laboratory environment utilizing a commercial main landing gear assembly. Phase II will continue to advance technological readiness to include full development, demonstration, and validation of the ES3 STORM system, utilizing the equipment and approaches identified during the Phase I effort. The demonstration and validation will be in a high fidelity laboratory environment, on a representative landing gear system. BENEFIT:ES3 anticipates the results of Phase II work will validate the feasibility and need for immediate pursuit of Phase II.5/III efforts. ES3 anticipates that current SMS technology is available to design and prototype a system that will meet the objectives of the program. The immediate benefit will be the ability to warn operators of low fluid level. This, in turn, will allow for more intelligent maintenance requirements, or inspection and repair intervals. This will maximize the utilization of the landing gear components, without compromising their safe operation; which will ensure life cycle cost reductions.