NASA has added two decommissioned F-15 fighter jets to its research fleet, a strategic move to accelerate testing of its X-59 “quiet” supersonic aircraft. The jets, acquired from the U.S. Air Force in December 2025, will play a critical role in gathering data and supporting flight operations for the groundbreaking X-59 project.
The Quest for Quiet Supersonic Flight
The X-59 is designed to break the sound barrier without creating the disruptive sonic booms that have historically limited supersonic travel. If successful, this technology could revolutionize air travel, dramatically reducing flight times across long distances, and opening new possibilities for industries reliant on rapid transit. This is a significant challenge because the conventional shockwaves generated at supersonic speeds are not just loud but also physically disruptive.
Role of the F-15s in Testing
One of the F-15s will be refitted with specialized research equipment, while the other will serve as a parts source to maintain the fleet. These jets will provide essential chase plane capabilities, allowing NASA researchers to collect real-time data during X-59 test flights. Specifically, they will carry sensors to measure air pressure changes caused by shock waves and house Schlieren photography systems to visualize airflow around the aircraft.
High-Altitude Data Collection
The F-15s are uniquely suited for this task due to their high-altitude performance. The X-59 typically cruises at 55,000 feet (17 km), but the modified F-15s can reach up to 60,000 feet (18 km) to gather critical data in the upper atmosphere. This altitude is vital because atmospheric conditions significantly influence how shock waves propagate and interact with the environment.
A Long History of F-15 Research
NASA has a decades-long track record of using F-15s for aeronautical research. Director of Flight Operations, Troy Asher, noted the aircraft have already contributed significantly to high-speed flight studies. The F-15s’ proven reliability and adaptability make them ideal for supporting cutting-edge projects like the X-59.
The X-59 itself completed its first test flight in October last year, with Lockheed Martin reporting the aircraft performed as expected. This latest addition of the F-15s signifies NASA’s commitment to pushing the boundaries of supersonic flight and underscores the importance of rigorous testing in achieving a quieter, more efficient future for air travel.
