NASA Had Its Very Own F-15 Fighter For a Special Reason

Summary and Key Points: NASA operated a unique F-15 fighter jet, known as the F-15 Flight Research Facility, which was highly modified from its U.S. Air Force counterparts. This one-of-a-kind aircraft was used to test and demonstrate advanced integrated flight and propulsion control technologies.

-It was the first to showcase a fully integrated inlet-engine-flight control system and a Self-Repairing Flight Control System (SRFCS), among other innovations.

-The F-15 was involved in over 25 research projects, including testing the Space Shuttle’s thermal protection tiles, contributing significantly to NASA's aerodynamics, propulsion control, and safety advancements.

NASA Had A Special F-15 Fighter

Did you know that NASA operated a single F-15 fighter jet? NASA’s lone F-15 was a highly modified version of its U.S. Air Force counterparts. NASA used this aircraft to demonstrate and evaluate advanced integrated flight and propulsion control technologies. 

The jet was known as the F-15 Flight Research Facility. 

One of a kind

The F-15 Flight Research Facility is the only aircraft of its kind ever made. The jet hit plenty of other firsts, too, as “the first aircraft to demonstrate a fully integrated inlet-engine-flight control system, a self-repairing flight control system, and a propulsion-only flight control system,” NASA explains.

Whereas a standard F-15 features mechanical electronic flight controls, the NASA F-15 carried a dual-channel, fail-safe digital flight control system. The result was an airframe used across an expansive flight envelope to conduct “complex and sophisticated research projects.”

Here are a few of the systems that the F-15 Flight Research Facility testing helped to develop: ADECS (Adaptive Engine Control System); SRFCS (Self-repairing Flight Control System); PSC (Performance Seeing Control); and PCA (Propulsion Controlled Aircraft). Not bad for a single testing platform. 

In all, the F-15 was used for “more than 25 advanced research projects involving aerodynamics, performance, propulsion control, control integration, instrumentation development, human factors, and flight test techniques.”

Perhaps the most publicly prominent test the F-15 Flight Research Facility ever conducted was for the Space Shuttle’s thermal protection tiles. The tiles coat the surface of the Space Shuttle to act as a collective heat shield during re-entry to the Earth’s atmosphere. They were notoriously difficult to design, manufacture, and install on the Space Shuttle. The F-15 had a significant role getting the tiles dialed in and ready for installation, which allowed the Space Shuttle to finally take flight – one of NASA’s biggest wins ever.

Learning to Fly

NASA’s F-15 was the first aircraft to demonstrate a Self-Repairing Flight Control System. The SRFCS “demonstrated the ability of a flight control system to identify the failure of a control surface and reconfigure commands to the other control devices such as ailerons, rudders, elevators, and flaps to continue the aircraft’s mission or allow it to be landed safely,” according to NASA.

Here’s an example of how the SRFCS might work: A rudder is damaged, or fails entirely mid-flight. The SRFCS identifies the dead rudder and calculates how the still-functioning flight surfaces can be adjusted to compensate for the dead rudder. Meanwhile, the SRFCS displays information in the cockpit telling the pilot how the remaining flight surfaces are being reconfigured, The pilot also learns the new operational limits resulting from the reconfigurations, i.e. reductions in “G’ loading, airspeed, angle-of-attack, and altitude.

In addition to identifying failures in flight surfaces, the SRFCS could diagnose failures in the jet’s electrical, hydraulic, and mechanical systems.   

About the Author: Harrison Kass 

Harrison Kass is a defense and national security writer with over 1,000 total pieces on issues involving global affairs. An attorney, pilot, guitarist, and minor pro hockey player, Harrison joined the US Air Force as a Pilot Trainee but was medically discharged. Harrison holds a BA from Lake Forest College, a JD from the University of Oregon, and an MA from New York University. Harrison listens to Dokken.

Image Credit: Creative Commons.