NASA Completes X-59 Supersonic Jet Engine Tests

The General Electric F414-GE-100 engine is a modified version of the powerplant used in fighters like the F/A-18 Super Hornet and Sweden's Saab JAS 39E Gripen. For the X-59, GE updated the engine's external design and control systems while retaining the core turbomachinery, allowing it to produce 22,000 pounds of thrust with its afterburner. The aircraft is designed to cruise at Mach 1.42 (937 mph) at an altitude of 55,000 feet. Its unique airframe, especially the nearly 33-foot-long nose, is engineered to shape and spread out shockwaves, preventing them from coalescing into a loud sonic boom. The result is a projected ground noise level of just 75 perceived level decibels (PLdB)—comparable to a car door closing. To further mitigate noise, the F414 engine is mounted on the top of the fuselage, shielding some of its sound from reaching the ground. The airframe also incorporates proven components from other aircraft to reduce cost and risk, including a canopy from a T-38 trainer and landing gear from an F-16. Due to the elongated nose, the pilot has no forward visibility. Instead, they rely on an eXternal Vision System (XVS) that uses a high-resolution camera to feed a 4K monitor in the cockpit, providing the critical forward view for navigation and landing. Following initial airworthiness flights at NASA's Armstrong Flight Research Center, the X-59 will undergo acoustic validation over the Edwards Air Force Base test range. This phase will use techniques like air-to-air Schlieren imaging to visually confirm the shockwave patterns match computational fluid dynamics models. The final phase of the QueSST mission involves flying the X-59 over several U.S. cities to gather data on public perception of the quiet "sonic thump." This community response data is critical for the ultimate goal: providing the FAA and international regulators with the information needed to establish a new noise-based standard for supersonic flight over land.