sentences:  A mixture of carbon and fiberglass is used for various elements, including the Friese ailerons and air brakes.Normal behaviour of both ailerons and air brakes has been observed even during deliberately-induced stall conditions.In the early 1990s, RFB and Rockwell International developed in a joint venture a jet-powered variation of the Fantrainer under the denomination Ranger 2000, which was evaluated as a trainer aircraft in the JPATS contest by the USAF and the U.S. Navy, but no orders were placed as the aircraft lost to the T-6 Texan II.