North American P-51 Mustang Cavalier Mustang

The Cavalier Mustang grew out of an unusual idea: turning surplus Second World War fighters into fast business aircraft. In 1957 Florida newspaper publisher David Lindsay (1922–2009) founded Trans Florida Aviation in Sarasota to convert surplus military P-51s into executive aircraft. Many of the airframes and spares came from scrap dealers who intended to melt them down, and Lindsay built up an immense stockpile of P-51 parts that he sold to Mustang owners worldwide. The first aircraft were called the Trans-Florida Executive Mustang and were soon renamed Cavalier Mustang. The first was built in 1958, and for the next few years only a handful of airframes were built and sold.

The process was a complete remanufacture: each P-51 was fully disassembled, stripped of its military equipment and rebuilt with a second seat (a "tight" seat fitted in the space formerly occupied by the military radio and the fuselage fuel tank), new avionics, leather interiors, luggage bays and civilian paint schemes. By 1961 the aircraft fitted with wingtip tanks were renamed Cavalier 2000, after their approximate range of 2000 miles (about 3200 km). Five models were eventually offered, the Cavalier 750, 1200, 1500, 2000 and 2500, differing in fuel capacity, the number giving the approximate range in miles. Nearly 20 civil examples were built over the following decade. The company obtained FAA approval for a series of improvements: canopy-frame fresh air vents, wingtip fuel tanks, a fuselage baggage door, fuel tanks in the gun and ammunition bays, an autopilot, a high-pressure oxygen system and a vertical fin 36 cm taller. Trans Florida did not just sell the aircraft: it trained new owners to fly them and maintained them after purchase. North American Aviation itself, the Mustang's original builder, bought two Cavaliers for its famous test pilot R. A. "Bob" Hoover, one in 1962 and another in 1971, to promote the company name at air shows.

Between 1964 and 1965 Trans Florida inspected and overhauled more than 30 Dominican Air Force F-51Ds in Sarasota, with State Department approval. In 1967, because of the strong identity of its product, the company was renamed Cavalier Aircraft Corporation, and that same year the Department of Defense contracted it to build military-specification F-51Ds for export under the Military Assistance Program (MAP). These Cavalier F-51Ds kept most of the civil improvements but were optimised as ground-attack fighters: nine single-control aircraft and two dual-control TF-51Ds were built. According to the main P-51 article, these remanufactured aircraft received new V-1650-7 engines, a new radio, tall F-51H-type fins and a stronger wing with six 12.7 mm machine guns and eight underwing hardpoints able to carry two 450 kg bombs and six 127 mm rockets; they kept the original F-51D canopy with a second seat for an observer, while TF-51D 67-14866 had an enlarged canopy and only four guns. They were delivered to the USAF in full USAF markings but with new serial numbers (67-14862/14866, 67-22579/22582 and 72-1526/1541). Nine, including the two two-seaters, went to Bolivia under the "Peace Condor" programme. The US Army, which had used a vintage F-51D as a chase aircraft for the Lockheed YAH-56 Cheyenne helicopter, ordered two F-51Ds from Cavalier in 1968 for Fort Rucker, fitted with wingtip tanks and unarmed (68-15795 and 68-15796); the first was used to evaluate a 106 mm recoilless rifle and the second survives at the Air Force Armament Museum at Eglin Air Force Base, Florida.

Also in 1967 Cavalier developed the Mustang II, an outgrowth of the F-51D for close air support and counter-insurgency, with improved avionics, a strengthened wing with four additional hardpoints and an improved Rolls-Royce Merlin V-1650-724A. Two batches were built: five Mustang IIs, one of them a TF-51D, for El Salvador in 1968, with wingtip tanks to extend combat range, and five Mustang IIs and one TF-51D for Indonesia in 1972 and 1973, without tip tanks because of a State Department restriction. The Indonesian aircraft were completed under the USAF "Peace Pony" contract by Field Services Inc., the company Lindsay set up after closing Cavalier Aircraft Corp. in 1971 to work on the Piper PA-48 Enforcer, a turboprop derivative that began in 1968 as the Cavalier Turbo Mustang III and is a separate aircraft. The documented specifications are those of the Cavalier F-51D: a 1,283 kW Rolls-Royce Merlin 724 driving a four-blade Hamilton Standard propeller, a 12.60 m span with tip tanks, a gross weight of 6,350 kg, a maximum speed of 708 km/h, a range of 3,218 km and a service ceiling of 11,465 m. Many civil conversions and a number of re-imported military Cavaliers have since been restored as P-51Ds and still fly on the air show circuits of the United States and Europe, often retaining Cavalier improvements.