The Northrop YA -9A was the prototype of a Erdkampfflugzeuges the Northrop Corporation.
The YA -9 was developed as a counterpart to the A-10 Thunderbolt for the AX (Attack Xperimental ) of the U.S. Air Force. For those awarded in April 1967 orders for Studies and revised in May 1970 specifications for these various aircraft manufacturers. The requirements were high; so the machine with 300 m off distance should be commented, a 180 - degree turn should be at full load and about 300 km / h is also just 300 meters take to complete, and the duration of use in the target area should not be less than five hours. The price per aircraft was determined to be not more than 1.4 million U.S. dollars. For this call the YA -10A and the YA -9A went on May 18, 1970 as the winner, and so two prototypes were ever built for a comparison flies. Northrop awarded $ 28,900,000 for this order. The prototypes were built in Hawthorne, New York and had on 30 May 1972 ( 71-1367 with Lew Nelson at the wheel ) and on 23 August 1972 ( 71-1368 ) in Edwards its maiden flight. The Y -9A was defeated after three months of test flight just the A-10, the prototype according to the decision of January 18, 1973 were shortly to NASA and then to various museums ( March Air Field Museum and Edwards).
The aircraft is a high wing with unswept wings and two turbofan engines ( derivatives of T55 helicopter drive with geared turbofan ) in the wing roots. The large horizontal stabilizer had a V- position, and the control was a combined side and aileron control ( lateral force control). It is armed with a 30 mm Gatling gun GAU- 8 / A Avenger was provided, but was replaced in the prototypes lack of availability through a 20 -mm M61 Vulcan cannon. This represented the main armament of the aircraft and caused by their dimensions some constructive changes - so the large body diameter and the lateral offset of the nose wheel. The cockpit was armored with a five centimeter layer of light metal ( the prototype of aluminum; titanium for the series was planned). The controller was designed redundantly in order to increase survivability.