The US Defense Advanced Research Projects Agency (DARPA) has successfully conducted a series of test flights on a converted Lockheed Martin F-16D fitted with a flight control system (FCS) that uses artificial intelligence (AI) software.
The former NF-16D – rebadged in 2021 with the X-62A designation – is operated by the USAF Test Pilot School at Edwards AFB in California. Also known as VISTA (Variable In-flight Simulator Test Aircraft), the aircraft was converted to the X-62A under DARPA’s Air Combat Evolution (ACE) program to demonstrate how AI software can control a full-scale aircraft in flight.
A 13 February DARPA release says the test flights also involved pilots from the USAF TPS, with the Air Force Research Laboratory (AFRL), Lockheed Martin, and AI-development contractors CALSPAN also contributing to the program.
“Thanks to the outstanding teamwork and coordination between DARPA, the Air Force Test Pilot School, the Air Force Research Laboratory, and our performer teams, we’ve made rapid progress in Phase 2 across all areas of the ACE program,” DARPA program manager for ACE, LtCol Ryan Hefron said in the release. “VISTA allowed us to streamline the program by skipping the planned subscale phase and proceeding directly to a full-scale implementation, saving a year or more and providing performance feedback under real flight conditions.
“We conducted multiple sorties with numerous test points performed on each sortie to test the algorithms under varying starting conditions, against various simulated adversaries, and with simulated weapons capabilities,” he added.
“We didn’t run into any major issues but did encounter some differences compared to simulation-based results, which is to be expected when transitioning from virtual to live. This highlights the importance of not only flight-testing advanced autonomous capabilities, but doing so on testbeds like VISTA which allowed us to rapidly learn lessons and iterate at a much faster rate than with other air vehicles.”
Several different algorithms were trialled on the X-62A, the FCS of which can be programmed to demonstrate the flight-handling characteristics of different aircraft types. Despite being capable of operating autonomously, the aircraft carried a safety pilot who could take control if required.
The aim of the program is to develop AI models that can be applied to uncrewed aircraft such as those being developed for the AFRL’s Skyborg program. The AFRL describes Skyborg as an “autonomous aircraft teaming architecture that will enable the Air Force to posture, produce, and sustain mission sorties at sufficient tempo to produce and sustain combat mass in contested environments.”
Uncrewed and optionally-crewed air vehicles from General Atomics, Northrop Grumman’s Scaled Composites, Kratos, and Boeing have also participated in the Skyborg development program using various levels of autonomy and AI.