https://www.dau.edu
Furthermore, the report directed the Secretary of the Air Force to provide a roadmap to transition in the FY 2021 budget submission, including cost, schedule, competition, and transition plans to other programs supporting advanced engine development, EMD, and production activities. The Air Force, apprehensive about committing to technology that was not fully proven, remained noncommittal, stating that transition plans would be informed by the results of the ground testing (anonymous personal communication, January 11, 2024). While the Air Force wrestled with the following steps, the program continued executing, initiating testing of GE’s XA100 engine in December 2020 (GE Aerospace, 2021). Over the next three years, the XA100 completed three phases of testing, logging hundreds of hours of whole-engine performance and operability testing, including time at the Arnold Engineering Development Complex, where the engine was “flown” at simulated altitude pressures and temperatures (GE Aerospace, 2023b). The Air Force initiated testing of P&W’s XA101 in late 2021 (Tirpak, 2021). Few details on the XA101 testing are available in the public forum. However, the Congressional Research Service reports that the engine was still in testing as of September 2022 and that the XA101 testing remains on track and aligned with the Air Force’s development timeline (Hoehn & Parrish, 2022). Meanwhile, separate from AETP, the F-35 powerplant, the F135 engine, had started experiencing challenges. As detailed by the GAO, F135 sustainment posed the most significant sustainment risk for the F-35 over the next 10 years. F-35 aircraft needing engine repairs were growing, with 20 aircraft down for engine maintenance by the end of 2020. The JPO was projecting that if nothing was done, the program would have
119
Defense ARJ , Summer 2025, Vol. 32 No. 2: 104—130
Made with FlippingBook - Online Brochure Maker