Landing Gear Structural Health Prognostic/Diagnostic System

Landing gear systems are one of the more problematic subsystems on Naval aircraft. Landing gear failure can be caused by hard landings due to actual severe high sink rate with high enough GW to exceed the design strength, but are extremely rare. More common are fatigue and environmentally caused failures. Aircraft managers address this issue by making estimations of operational loads, and doing detailed fatigue analysis as appropriate to ensure safe landing gear operation. These estimations are conservative by nature, and frequently necessitate assumptions about landing, ground or braking conditions that may be different in actual operational service. The ability to measure, record, and possibly process the operational loads data for each aircrafts landing gear would give Aircraft Program Offices the ability to make more intelligent management decisions about operational limits, inspection intervals, and removal & depot overhaul cycle values. Additionally, landing gear failures can be caused by mis-servicing of the landing gear, resulting in much higher loads (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 proposed SHM system would address this issue at two levels - detecting and prevent mis-servicing gears hence eliminating higher peak load failures, and also minimize/avoid unnecessary inspections due to perceived "hard landings". ES3 proposes to address all these issues through the use of an on-aircraft miniaturized data acquisition system, with sufficient data storage and processing capabilities to utilize multiple sensor inputs. During the Phase I SBIR effort, ES3 evaluated several of these systems, and numerous applicable sensors for their suitability in a SHM system. During the Phase I activities, prototype hardware was laboratory tested for various SHM functionality. The N121-043 Phase II effort intends to capitalize on the significant opportunity to resolve problems with the current SHM systems/datavia the integration of new technologies for sensors, communication devices, and miniaturized Data Acquisition Systems (DAQ). In Phase I, ES3 demonstrated the technical feasibility of developing this type of multi-function SHM system that could address four main categories 1) fatigue life management, 2) safety, 3) maintenance reduction, and 4) mission impactin order to aid in the technology evaluation process The primary focus of the Phase II solution will be development/demonstration/validation on the P-8 (PMA-290) acquisition program. However, the proposed solution will be directly transferable to other acquisition programs included in the N121-043 SBIR topic, currently including V-22 (PMA-275), C-130 (PMA-207), and H-53K (PMA-261).