at the Glenn Research Center in Cleveland, Ohio, where it was used for propulsion experiments involving turboprop engines. In 1996 this aircraft was moved Dryden as a chase aircraft. That aircraft was returned to the U.S. Navy in 2002. The second T-34C was obtained in early 2005 from the Naval Air Warfare Center Aircraft Division (NAWCAD) at NAS Patuxent River, where it was due to be retired. At Armstrong, the T-34C is primarily used for chasing remotely piloted unmanned air vehicles which fly slower than NASA's F/A-18 mission support aircraft can fly. As a NASA mission support chase plane, the back seat would be occupied by a photographer or flight test engineer during research missions. It is also used for required pilot proficiency flying. Non-U.S. military service As of 2007, Mentors are still used by several air forces and navies. From 1978, the T-34C Turbo-Mentor was the Argentine Naval Aviation basic trainer used by the 1st Naval Aviation Force (Training), alongside 15 T-34C-1 light attack aircraft forming the Fourth Naval Air Attack Squadron. During the 1982 Falklands War, four T-34C-1s were deployed to Port Stanley on 25 April 1982, primarily to be employed in a reconnaissance role. The main encounter with British forces occurred on 1 May 1982 when three Turbo-Mentors attacked a Royal Navy Westland Sea King helicopter in the area of Berkeley Sound but were intercepted by Royal Navy Sea Harriers flown by Lt 'Soapy' Watson and Lt Cdr 'Sharky' Ward of 801 Naval Air Squadron flying from HMS Invincible, with one of the T-34Cs being damaged by cannon fire from Ward's aircraft. The four T-34C-1 Turbo-Mentors continued to operate, flying a few reconnaissance missions, but were redeployed to Borbon Station where they were ultimately destroyed by the SAS Raid on Pebble Island on 15 May 1982. Although all four hulks remained on the island for a considerable length of time, eventually, 0729/(1-A)411 was recovered on 10 June 1983 and stored for future display at the Fleet Air Arm Museum. Civilian use In 2004, due to a series of crashes involving in-flight structural failure during simulated combat flights, the entire US civilian fleet of T-34A/Bs was grounded by the Federal Aviation Administration. The grounding has since been eased to a slate of restrictions on the permitted flight envelope. Via a series of Airworthiness Directives (ADs) established by or Alternate Methods of Compliance (AMOCs) negotiated with the FAA, including