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Northrop Grumman Systems Corp. in San Diego, CA received an $8.2 million contract to provide Phase II data rate communications upgrades for the Aircraft Structural Integrity Program (ASIP).
The US Air Force initiated the ASIP because of catastrophic, unanticipated, in-flight fatigue failures of in-service aircraft. ASIP is the management tool for the USAF to safely manage the fleet from initial operating capability through the design service goal and beyond.
The program focuses on monitoring the structural integrity of USAF aircraft, including:
* B-2 bomber
* B-52 bomber
* C-17 transport aircraft
* E-8C surveillance aircraft
* C-5 transport aircraft
* F-15 fighter
* A-10 close air support aircraft
* F-16 fighter
The primary analysis tool to determine the fatigue life of a structural component in ASIP is linear elastic fracture mechanics (LEFM). In this effort, 9 LEFM parameters were identified that affect the fatigue life: initial flaw assumption, boundary correction factor, load interaction models, crack growth rate data, stress intensity factor, threshold stress intensity factor, yield stress, and critical stress intensity factor. Data on these factors is collected and analyzed on the aircraft.
At this time, $2 million has been obligated under the Northrop Grumman contract. The 303 AESG/SYK at Wright-Patterson Air Force Base in Ohio manages the contract (F33657-01-C-4600).