Wild Argentinian Mustango's

**Spinners** · August 4, 2018

Rockwell F-31K Mustang II - Grupo 6 de Caza, Fuerza Aerea Argentina, 2018

The X-31 experimental jet fighter was designed and built by Rockwell and Messerschmitt-Bölkow-Blohm as part of a joint US/Germany 'Enhanced Fighter Maneuverability' programme to test thrust vectoring technology in both pitch and yaw allied to an advanced flight control system to provide controlled flight at very high angles of attack. Whilst being a radical new design the X-31 used a wide variety of parts from previous production aircraft including the F/A-18 Hornet front fuselage (including the cockpit, ejection seat and canopy) and the F-16 Fighting Falcon's landing gear plus the Cessna Citation's main landing gear wheels and brakes. This dramatically reduced the development time and risk by using flight-qualified components and enabled the first of just two X-31's to take to the air on October 11th, 1990 and over 500 test flights were flown between 1990 and 1995.

With a huge fall in defence spending from the 'peace dividend' Rockwell began to look at ways of using many of the X-31's technologies in a low-cost fighter aircraft and in 1992 they proposed an 'F-31' version powered by a non-afterburning version of the General Electric F110 turbofan rated at 16,000lbs dry thrust. Deleting the thrust-vectoring and afterburner reduced a considerable amount of weight from the rear fuselage and Rockwell calculated that the lack of an afterburner would give the small and light F-31 such an increase in range that most missions could be flown without external drop tanks. On the home-front Rockwell proposed an A-31 version to supplement and eventually replace the A-10 Thunderbolt claiming that the A-31 would be about one-half of the cost of the proposed A-16 Fighting Falcon.

But Rockwell's main efforts were on the export market and especially the Gulf States and Saudi Arabia and it was interest from the latter and also South Korea that encouraged Rockell to proceed with development at the end of 1993. Marketing their new fighter as the 'F-31 Mustang II' orders were placed by South Korea (72) and Saudi Arabia (59) followed by a home order of 30 aircraft for the US Navy to supplement their F-5E Aggressor Force and then 100 A-31C's for the US Air Force.

In December 1998, the Royal New Zealand Air Force became the third export customer when they placed an order for 34 F-31K's to replace it's ageing Skyhawks but the acquisition was cancelled by the new Labour government in March 2000 in a controversial move as "an air combat force is not a priority in the current benign security environment". With most of the F-31K's having already rolled off the production line Rockwell did not take the cancellation lightly and, faced with huge cancellation charges, the New Zealand government breathed a sigh of relief when the Argentinian Government, led by Fernando de la Rúa, negotiated the purchase of the 34 F-34K's for the Fuerza Aerea Argentina at a reduced price. Entering service with Grupo 6 de Caza in August 2001 the F-31K's continue in service based at the Tandil Military Air Base in the Buenos Aires Province.