AEDC's accelerated mission test provides savings for the U.S. Air Force Published Sept. 25, 2014 By Deidre Ortiz AEDC/PA Arnold Air Force Base, TENN. -- Project engineers at Arnold Engineering Development Complex (AEDC) have led a significant effort in accelerating mission testing (AMT) that will ultimately result in a large payoff for the Air Force. A 15-month AMT of Pratt & Whitney's F100-PW-220 engine, which powers the Air Force fleet of F-16 Fighting Falcons and the F-15 Strike Eagles, was recently conducted in AEDC's Sea Level 3 (SL-3) test cell. The test, part of a $17.5 million program, which ran from January 2013 until spring of this year, is one of the longest running jet engine tests in AEDC history. This successful test has extended the life of the F100-PW-220 by two years, from 8 years to 10. "We were able to take the engine from 4,000 to 5,000 calculated cycles," said 1st Lt. Stuart Coston, Air Force team leader for the project. "Essentially, it eliminates an entire depot level overhaul in the engine life cycle." Tom Schmidt, ATA project manager for AEDC's Aeropropulsion Products Branch, added that increasing the time between performing a major overhaul of an engine is financially beneficial for both the government and taxpayers. "Benefits include a more dependable engine for the pilots and cheaper costs to maintain for the depots and taxpayers," he said. "This will potentially save [the Air Force] many millions of dollars in depot maintenance costs when applied to the fleet of F100-PW-220s in service." It's estimated the test will actually lead to a more than $100 million savings in reduced depot overhaul costs through 2045. An AMT simulates the operational stresses the engine would experience in flight between depot overhaul visits. Jeremy Morris, lead project engineer, explained the objectives of this AMT were to demonstrate the durability of the bill of material (BOM) and task hardware by exposing it to 5,000 CCYs via test standards. "This is done by running the engine through carefully designed throttle profiles, representing different missions of the F-15 and F-16 aircraft in service," he said. "In simpler terms, we simulate about 15 years of wear and tear the engine would see in service before needing to be overhauled and see how the hardware performs and endures. When complete, the engine is sent back to Logistics Command and is torn down for detailed inspection of all its parts." The test crew worked together seamlessly in completing the AMT, finding several ways to achieve desired results while remaining on schedule. Test engineers Bernie Williamson and Ray Joellenbeck were instrumental in coordination of inspections and maintenance between SL-2 and SL-3 given the project's reduced manpower requirements. In addition to reduced staffing, testing changed from a two-shift operation to around-the-clock test coverage, decreasing the test schedule by more than a month. Lastly, the test team was in constant coordination with multiple AEDC test support resources to minimize project delays. Paul Kelly, senior analysis engineer, explained that "the test results provided engine performance, durability and reliability assessments, and documented engine hardware component distress." Innovative thinking during the planning stages of the project resulted in the creation of modified mission profile definitions. These modifications decreased engine fuel consumptions and resulted in savings of $524,000 for the systems program office. Team leaders applauded the project team on a job well done. "Aerospace Testing Alliance personnel worked around the clock to ensure the test was completed on time," Coston said. The test team incorporated lean staffing and efficiencies to run 1,968 test hours for 58 weeks. On two occasions during this program, the F100 was one of five engines testing simultaneously at AEDC. Due to the efficient use of manpower and resources, the test exceeded customer expectation and was completed at $733,000 under cost. Morris explained testing in the AEDC sea level test cell also had its advantages. "By using SL-2 or SL-3, we can operate at sea level ambient, variable inlet RAM or heated inlet sea level without RAM," he said. "Having the ability to test with multiple facility configurations offers the test customer an additional measure of flexibility during a crowded test window." Completion of this test marks the successful demonstration required to certify and extend the service life of the engine for the F-15 and F-16 by 25 percent. For their outstanding effort, the F100 test team was recently presented the General Lee Gossick Team Excellence Recognition.