Super Stang

The Mustang rejuvenation story began with the efforts of Cavalier Aircraft’s Mustang refurbishment program which it undertook on behalf of the USAF for the supply of upgraded twin seat P-51Os to approved South American nations. Cavalier had built up substantial expertise in the modification of the Mustang airframe both for private and military purposes. Indeed through the ’50s and ’60s many stored Mustangs were drawn from Davis Monthan to be totally re-built for two-seat executive use and later for closed-circuit air racing.

A dream of Cavalier President, David Lindsay Jnr, was to actually adapt a turboprop power plant to the standard Mustang so as to increase performance and overall capabilities. This project led to the Cavalier Mustang III which was powered by a 1670eshp Rolls-Royce Dart turboprop straight from a Viscount airliner. The Viscount style cowling was also adapted in place of the standard Mustang nacelle, the wings and spars were strengthened while the tail was increased in height by 14 inches to afford better low speed directional control so important in COIN operations.

The first prototype flew in mid-1968 and commenced a relatively slow test program dictated by economics more than market objectives. The lower powered Dart turboprop was soon replaced with a Dart Mk 529 of 2100eshp which enabled the aircraft to reach maximum speeds in the order of 540mph – almost a full 100mph faster than its World War II brother. The Cavalier Turbo Mustang Ill was armed with the standard six, 50 calibre machine guns of the original Mustang and could carry 5000Ib in stores on six underwing stations. The aircraft also featured wingtip tanks each of 110 gal capacity which more than doubled the standard P-51 tankage. In the COIN role the Turbo Mustang Ill could operate from semi-prepared strips of less than 2000ft and remain on loiter for a full two and a half hours.

The Turbo Mustang Ill has demonstrated to the USAF for possible use as a COIN aircraft but little real interest was forthcoming resulting in another redesign of the airframe to make it eligible for the forthcoming USAF Pave Coin program.

The new aircraft was re-engined with the American-produced Avco Lycoming T55 of 2535hp and featured a revised cockpit layout and redesigned canopy, all of which gave the new aircraft, named Enforcer, a bulkier appearance than the early Turbo Mustang Ill. It was at this time that Cavalier sold the entire project to Piper as the former company was on the verge of bankruptcy.

Piper developed the original Enforcer prototype and developed a second test aircraft to meet the requirements of the Pave Coin project. Unfortunately, the Enforcer was not chosen and so the entire program was abandoned.

The Enforcer had 10 ordinance stations capable of carrying a combined offensive load of 548OIb not including the six original 50 calibre machine guns and 2000 rounds of ammunition. At 14,000lb the Enforcer had a ground roll of only 1100ft and could clear a 50ft obstacle in 1680 feet, quite an achievement by any COIN standard. Similarly stalling speed at normal landing weight was 78kts for a ground roll of only 880ft. The Enforcer achieved a high level of combat manoeuvrability, provided rapid throttle response, was a stable gun platform, could sustain BG and from a low level, attack could zoom climb to 3000ft in 10 seconds.

If the Enforcer had succeeded it would have ensured the continuation of a design heritage that was born in the smoky atmosphere of a London hotel back in January of 1940 when the plans for the original P-51 were conceived between high-ranking RAF officers and a handful of North American Aviation designers. Alas, that was not to be.