Mustang Oddities Part 2
CAC 17 Mustang, Piper Enforcer, CA 15 Kangaroo and Cavalier Mustang
CA 17 Aussie Built Mustang
In 1942 the Royal Australian Air Force (RAAF) was looking for a new fighter aircraft.
They decided on the P-51 Mustang as their high altitutde interceptor. In late 1943, an agreement between NAA and the RAAF was reached. An Australian aircraft company, Commonwealth Aircraft Corporation (CAC), would build P-51Ds under license in Australia.
As part of the agreement, NAA would supply 100 P-51D Mustangs disassembled and Packard would supply some 80+ -3 Merlin engines. Delays mounted and the first CAC P-51 did not fly until April 1945. In all, 80 P-51s were completed from these parts and designated CA-17 Mk.20, A68-1 to A68-80.
As the war came to an end, the total scratch built CAC P-51s was reduced to 120 aircraft. The CAC new built P-51s were designated CA-18. Versions would be the Mark 21, Mark 22, and Mark 23.
The Merlin V-1650-7 was used in the CA-18Mk.21 models. The CA-18Mk.23 use the British built Rolls Royce Merlin 66 or 70 versions. The CA-18Mk.22 were modified like the F-6D reconnaissance versions. The last CA-18Mk.23 came off the production line in 1952.
Australia also received 298 P-51Ds from the U.S. under Lend-Lease. After the Aussie Mustangs were surplussed, Australia became a popular site for P-51 airframes and parts.
Restorerers and collectors alike would travel down under to make deals and trades. Several P-51s have remained in Austalia and are kept airworthy and well cared for by their pilots and owners.
Piper Enforcer
In 1968, Cavalier Aircraft developed a highly modified version of the Cavalier Mustang for use as a counter-insurgency aircraft. Cavalier initially mated a Rolls-Royce Dart 510 turboprop to a Mustang II air frame.
This privately-funded prototype was also intended for the same CAS/COIN mission that the Mustang II was built for. The Turbo Mustang III had radically increased performance, along with an associated increase in payload and decrease in cost of maintenance, and was equipped with Bristol ceramic armor to protect the engine, air frame and pilot. Despite numerous sales attempts to the United States Air Force, neither the U.S. military nor any foreign operators purchased the Turbo Mustang III.
Seeking a company with mass production capability, the Turbo Mustang III, renamed the "Enforcer," was sold to Piper Aircraft in late 1970. Cavalier Aircraft Corp. was closed in 1971 so the founder/owner, David Lindsay, could help continue develop the Enforcer concept with Piper. Piper was able to lease a Lycoming T-55L-9 engine from the USAF (the engine Lindsay wanted initially) and flew the aircraft some 200+ hours. In 1984 with a $US12 million appropriation from Congress, Piper built two new Enforcers, giving the new prototypes the designation PA-48. These aircraft were evaluated by the USAF, but flown only by Piper test pilots.
In 1971, Piper built two Enforcers by heavily modifying two existing Mustang airframes, fitting them with Lycoming YT55-L-9A turboprop engines along with numerous other significant modifications. One airframe was a single seat (called the PE-1 and FAA registered as N201PE), the other a dual-control aircraft (the PE-2, registered N202PE). Prior to the Pave COIN evaluation, N202PE was lost in a crash off the Florida coast on 12 July 1971 due to flutter caused by a Piper-modified elevator trim tab. Although the Enforcer performed well in the 1971–1972 Pave COIN test flown by USAF pilots, Piper failed to secure a USAF contract.
Cavalier
In 1957, the last of the active duty P-51s were withdrawn from service. This released many P-51s to the civilian market. David Lindsay, a newspaper publisher, formed Trans Florida Aviation with the intent of refurbishing the ex-military P-51s into well-equiped civilian business aircraft.
Lindsay purchased surplus P-51s (mostly P-51D) and began a restoration process. They would strip out all the military equipment, add a second seat behind the pilot, add extra fuel capacity (some models), update the avionics, install a tall tail similar to the NACA P-51s, plush out the interior to provide the most comfort possible and finish the job with a civilian paint scheme. Lindsay flew 44-13257, with the NACA tail, and was pleased how it handled. He got the FAA STC for the tail mod so the taller vertical stabilizer could be added to the civilian Cavaliers.
One of the P-51s main attributes was its great range. The first P-51 conversion, named Cavalier, was in 1958. Orders trickled in for the first few years. The models offered were all relative to the range of the aircraft. The model numbers (all prefixed by "Cavalier") were 750, 1200, 1500, 2000 and 2500. The longest range Cavalier, the Cavalier 2500, included 110 gallon wingtip fuel tanks. Remember, with the second seat, the fuselage fuel tank was removed and the main wing tanks would yield about 180 gallons usable.
Trans-Florida was renamed Cavalier Aircraft Corporation and purchased the rights of the P-51 design from North American Aviation. The first contract with the U.S. Government was to IRAN 36 F-51 from the Dominican Air Force (FAD). These were not Cavalier conversions but were P-51s that were repaired and upgraded. Then in 1967, the USAF contracted with Cavalier to produce the F-51D for export to South America under the Military Assistance Program (MAP). These aircraft were given new serial numbers starting with the first, 67-14862 and named "Mustang II". In 1967 a total of 9 were built. These aircraft went to El Salvador.
Changes to the Mustang II were made for increased loads. The wing was strengthened to carry a total of 4,000 lbs of ordance and additional weapon hard points were installed, up to six under each wing. A rear seat was installed in these models, for observers. A new Merlin V-1650-724 was installed and these Cavaliers also received the taller tail modification. In 1968, two of the new Mustang IIs went to the U.S. Army as chase planes for the Cheyene (AH-54) helicopter program. These were serialed 68-15795 and 68-15796.
More orders placed in 1972 for 6 aircraft under MAP for export to Indonesia. The Mustang IIs did not have wingtip fuel tanks.
With new ideas of how to keep the P-51 Mustang alive and in service, David Lindsay wanted to try replacing the long-standing workhorse Merlin V-12 with a turboprop. Lindsay perferred the Lycoming T-55 but had difficulties obtaining a copy. They were able to get a Rolls Royce Dart 510 Turboprop and installed it in civilian P-51 N6167U. This mod was not funded by the USAF, but by Cavalier.
The new modification was called the Turbo Mustang III. Cavalier tried to get the USAF and other air forces interested in the project but no sales were made. Later, Cavalier sold the project to Piper and it later became the PA-48 Enforcer. The Enforcer had little in common with the original P-51.
The USAF, under pressure from Congress, did order two prototype PA-48 from Piper. No other orders were place and the project died. The two PA-48 Enforcers do exist today at USAF Museums. Many Cavalier Mustangs are still airworthy today.
Evolution of the Mustang
P-51A; P-51B/C; two early P-51Ds; P-51H; Piper Enforcer.