Accession Number : ADA172400


Title :   Small, Self-Contained Aircraft Fatigue Data Recorder.


Descriptive Note : Final rept. Oct 85-Aug 86,


Corporate Author : ESPIRT TECHNOLOGY INC WALNUT CREEK CA


Personal Author(s) : Flanner,Philip


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a172400.pdf


Report Date : Aug 1986


Pagination or Media Count : 164


Abstract : Because of aging airframes and more severe mission requirements, the need to monitor structural fatigue damage on military aircraft has become critical. It is particularly important to be able to study the dynamic loads in remote locations such as the vertical tail, wing spar, landing gear, etc. However, there is presently no small, battery-operated data recorder available to investigate fatigue characteristics at these localized stress hot spots. Having available a miniature data-logger that could be easily attached to any desired location on an aircraft will enable engineers to quickly examine, and correct, the cause of fatigue cracks and similar structural problems. The purpose of this program was to investigate the feasibility of utilizing the latest technology in low-power circuitry, transducers and packaging to produce a small, rugged, self-contained fatigue recorder, requiring no tie-in to aircraft wiring for installation. The project stages included: feasibility study, design evaluation, submittal of an interim report, and culminated in the design layout and construction of a brassboard demonstration unit. This feasibility demonstrator is a single channel device connected to an internal accelerometer and includes a means for automatically activating the micro-processor circuitry by sensing the vibration associated with the start-up and operation of the aircraft's engines. Size of the ultimate unit is targeted at 8 cubic inches, and the demonstrator is approximately three times this volume because of using discrete devices rather than hybrids or SMD's.


Descriptors :   *MONITORS , *FLIGHT RECORDERS , LOW POWER , VIBRATION , MILITARY REQUIREMENTS , DETECTION , HIGH RATE , AIRCRAFT , MILITARY AIRCRAFT , AGING(MATERIALS) , DAMAGE , LIFE EXPECTANCY(SERVICE LIFE) , FATIGUE LIFE , AIRCRAFT ENGINES , ACCELEROMETERS , CRACKS , INTERNAL , SELF CONTAINED , MISSIONS , AIRFRAMES , PACKAGING , DATA STORAGE SYSTEMS , FATIGUE , TRANSDUCERS , RECORDING SYSTEMS , FATIGUE(MECHANICS) , CIRCUITS , WINGS , CHANNELS , STRUCTURAL COMPONENTS , LANDING GEAR , DEFECT ANALYSIS , ELECTRIC BATTERIES , BRASSBOARD MODELS , SPARS


Subject Categories : Aircraft
      Mechanics


Distribution Statement : APPROVED FOR PUBLIC RELEASE