The F-16 Fighting Falcon was produced by General Dynamics who became Lockheed who then merged with Martin Marietta to become Lockheed Martin. The F-16 entered service in January 1979 as a multi-role jet fighter that evolved into an all-weather multi-role aircraft capable of sustaining 9-g turns. The F-16 is relatively inexpensive to purchase and maintain so the U.S. and 25 other countries added it to their inventory. The Fighting Falcon is referred to by its pilots as the Viper and will remain in USAF service until 2025. In 1991 General Dynamics F-16A 82-0976 c/n 61-569 was transferred from the 3246th Test Wing, Eglin AFB, Florida to NASA located at Langley AFB. Here it was registered as N516NA #516 where its primary NASA mission was a chase plane for the two F-16XLs. On January 10, 1993 the aircraft was re-registered as N816NA and #816 and transferred to the Dryden Flight Research Center and used for engine testing. In 2004 the aircraft was withdrawn from service and is now on display in front of the Lockheed Skunk Works in Palmdale, California.