AEDC sea level facility helps validate sensors on turbofan engine Published Oct. 7, 2021 By Deidre Moon AEDC/PA ARNOLD AIR FORCE BASE, Tenn. -- The same nine vendors who visited Arnold Air Force Base as part of the Propulsion Instrumentation Working Group, or PIWG, meetings last fall recently returned. This time, instead of simply viewing an engine installed in the Arnold Engineering Development Complex Sea Level Test Cell 1 and making plans to test, they put SL-1’s capabilities to use by performing validation of new sensors and instrumentation. As part of the Engine Life Extension and Health Monitoring Program, or ELEHM, funded by the Air Force Research Laboratory Aerospace Systems Directorate, or AFRL/RQ, the sensor validation was completed on a military turbofan engine, specifically an F404 engine, originally developed by General Electric for the F/A-18 Hornet. The F404 engine was set up as a laboratory testbed. Modifications to borescope port viewing plugs and the low pressure turbine, or LPT, section of the engine allowed sensors to be installed through the engine case giving access to the gas flow path and LPT turbine blades. This enabled the sensors to be evaluated at high temperature and pressure conditions. Ohio Aerospace Institute, also known as OAI, assisted in overseeing the project as the prime contractor. Carol Cash, OAI program manager for the ELEHM program, stated it was a unique project and not an easy one to execute, so she is extremely pleased with the results of the F404 testing at Arnold. “It was certainly a challenging program with an unproven testbed and the pandemic in the middle of our test planning,” Cash said. “But AEDC rose to the challenge and executed a test that provided valuable engine data that helped to further mature multiple sensor and measurement technologies. “A special thank you to Bernie Williamson and Dr. Robert Howard and their team for all the hard work and support, and to Todd Pickering and the U.S. Navy for their assistance in helping to modify the F404.” Ruth Sikorski, aerospace engineer with the Turbine Engine Integrity Branch of the AFRL Aerospace Systems Directorate, or AFRL/RQTI, commended the AEDC team for its efforts in ensuring a successful test program. “Kudos to the team at AEDC for their flawless execution of a challenging program in the midst of an ongoing pandemic – all the while keeping their AFRL customers updated on the latest developments, good and bad,” she said. “As a result, we were able to solve problems in real-time before they had a chance to grow into major headaches.” Brian Runyon, a senior aerospace engineer with AFRL/RQTI, echoed her sentiments, noting that team set out to find a way to cost-effectively test sensor technologies in a large engine demonstrator and met every objective. “It is a true testament to what can be accomplished when you have a great team that is focused on success,” Runyon said. “The team leaders would like to express many thanks to participants from AEDC, AFRL, Navy, OAI and PIWG, who put in the long hours to make this happen. Not only was this new AEDC testbed critical to the ELEHM program, but there’s no doubt future programs will benefit from this as well.” The test has also been years in the making, according to Bernie Williamson, test project manager at Arnold. “We have been working with these vendors on this project since 2018,” Williamson said. “AFRL and PIWG are both happy with the outcome, but our AEDC team is also very excited to have accomplished the successful sensor validation, as to my knowledge, it had never been executed on a design and modified engine at that scale before.” This was just one of the most recent tests performed by PIWG, which has been in existence as a working group since 1995 to address turbine engine test instrumentation and sensor issues for the development of future gas turbine engine programs.