NASA’s Quesst mission has achieved a significant milestone with the start of tests on the X-59’s engine, the experimental supersonic aircraft. On October 30, 2024, NASA’s X-59 supersonic research aircraft ignited its engine for the first time at the Lockheed Martin Skunk Works facility in Palmdale, California.
The X-59’s engine, a modified F414-GE-100 with a thrust of 22,000 pounds, enables the aircraft to reach its target cruising speed of Mach 1.4 (1,488 km/h or 925 mph) at an altitude of around 55,000 feet. The engine’s unconventional placement on the aircraft contributes to the X-59’s quieter operation.
The engine operation tests, which began on October 30, allowed the X-59 team to verify that the aircraft’s systems work together while powered by its own engine. In previous tests, the X-59 used external power sources. These engine tests lay the groundwork for the aircraft’s next steps towards its first flight.
The engine tests are part of an integrated ground testing series necessary to ensure a safe flight and the mission’s objectives. Due to the challenges associated with reaching this critical testing stage, the first flight of the X-59 is now expected in early 2025. The team will continue with essential ground tests and address any technical issues found on this unique experimental aircraft.
The X-59 team will have a more precise date for the first flight as these tests are successfully completed. In the subsequent phases, the team will conduct high-power tests with rapid acceleration changes, followed by real-flight condition simulations.
In this initial phase, the X-59’s engine rotated at a relatively low speed without ignition to check for leaks and ensure all systems communicated properly. The team then refueled the aircraft and began low-power engine tests to verify that it and other aircraft systems operated without anomalies or leaks when powered by the engine itself.
“The initial engine testing was actually a warm-up to ensure everything looked good before running the engine“, stated Jay Brandon, NASA’s X-59 chief engineer. “We then moved to the first true engine start. This took the engine out of preservation mode, where it had been since installation on the aircraft. It was the first check to verify it was operating correctly, and that all impacted systems (hydraulic, electrical, environmental control, etc.) functioned as expected.”
The X-59 is an experimental aircraft that will fly supersonic without the typical loud sonic boom, aiming to revolutionize commercial supersonic flight. It will be the first of its kind to fly with this feature, with the goal of collecting sound data for NASA’s QueSST mission, which could pave the way for commercial supersonic flights over land, not just over oceans, in the future.
Today, commercial supersonic flight is allowed only over oceans. This restriction, implemented in 1973, has hampered commercial supersonic ventures, limiting faster-than-sound travel to oceanic flights. British Airways and Air France, which operated the Concorde, were two airlines that offered such services from 1976 to 2003.
The X-59 is at the heart of NASA’s QueSST (Quiet SuperSonic Technology) mission, which focuses on providing data to help regulators reconsider rules prohibiting commercial supersonic flight over land. For 50 years, the United States and other nations have banned such flights due to the noise impact of loud sonic booms on communities below. The X-59 is expected to fly at 1.4 times the speed of sound, at an altitude of 55,000 feet (16,764 meters). Its design, shape, and technologies will allow it to reach these speeds while generating a quieter sound.
Images: NASA / Carla Thomas