Cavalier Mustang & Enforcer

Executive Mustang

Design changes

Going military again

Last of the breed: the PA-48 Enforcer


Serial numbers

3-Way drawings



Going military again

In 1965 the company was contracted in by the government of the Dominican Republic, with US State Department approval, to IRAN (Inspect, Repair as Necessary) 36 aircraft in Sarasota.

Ironically, in the late 1960s and early 1970s, when the US Department of Defense wanted to supply aircraft for close air support and counter insurgency to friendly South American countries, it turned to Cavalier in order to meet the short deadline.

They contracted Cavalier in 1967 to produce F-51Ds for export under the Military Assistance Programme (MAP). They were named “Cavalier Mustang II” and given serial numbers starting with 67 and 68, the first being 67-14862.

The first Cavalier Mustang II flew in December of 1967.

These Mustang IIs incorporated most of the civilian Cavalier improvements but were optimized for ground attack. Changes were:

  • New Packard Merlin V-1650-724A engine which could produce 1,800hp

  • New radio package

  • Tall P-51H tail

  • Stronger wings which could carry six 0.50 caliber guns and eight underwing hardpoints which could carry a total of 4,000lbs of ordnance

  • A second seat was kept for an observer

  • Fixed wingtip tanks as with Cavalier 2000 and 2500 models

In 1967, the USAF ordered a batch of nine F-51D and two TF-51D dual control Mustangs were built. Nine were delivered to Bolivia (including the two TF-51Ds) under program “Peace Condor” and two went to the USAF for use as chase planes for the Lockheed YAH-56 Cheyenne helicopter gunship program (serials 68-15795 and 68-15796). After the Cheyenne program was cancelled they were used in short-term experiments in close air support operations. they eventually ended up in hands of the Navy for testing of wingtip-mounted 106mm recoilless rifles at NAS China Lake in the 1970s.

Photo by Bob Garrard
Above: 67-22581 was built in 1968 and served with the Bolivian Air Force as FAB 523. It currently flies as N151MC (44-15459/HL-B) as P-51D "American Beauty"

Although the F-51Ds were intented for South American and Asian nations, they were delivered with full USAF markings and serial numbers (67-22579 through 67-22582 and 72-1526 through 72/1541).

The USAF ordered a second batch of five Mustang IIs for export to Indonesia in 1972 under project “Peace Pony”. These did not have the wingtip fuel tanks due to a US State Department restriction. Five F-51Ds and one TF-51D featuring wingtip fuel tanks were sold to El Salvador.

David Lindsay wanted to take the Mustang one step further and mated the airframe with a turboprop engine in 1968. He prefer-red the Lycoming T-55, but was unable to obtain a license copy. He was able to get a Rolls Royce Dart 510 Turboprop engine and installed it in a civilian P-51 N6167U.

The modification was founded by Cavalier itself and was named Turbo Mustang III. Several attempts were made to get the USAF interested in the project, but to no avail. The Mustang III was designed for the close air support role and featured much improved performance, reliability, and lower maintenance costs. 

Cavalier Mustang II & Turbo Mustang III

Cavalier sold the Turbo Mustang III prototype and its rights to Piper Aircraft in November of 1970, where it became known as the PA-48 Enforcer. Cavalier Aircraft Corporation was sold and Lindsay moved on to work with Piper to assist with the Enforcer.



Last of the breed: the PA-48 Enforcer

The saga of the production Mustang ends with the story of the Enforcer.

At that time, the US was involved in the Vietnam War. Experience learned that a low-cost, high performance combat aircraft for close air support was needed. The project to evaluate such an aircraft was dubbed “Pave Coin”.

Cavalier originally built two privately funded prototypes: one single-seat airframe (PE-1, N201PE) and one dual-control air-frame (PE-2, N202PE). The first flight flight occurred on April 29th, 1971.

N201PE (Please contact me if you are the copyright owner of this photo)

The first prototype (N202PE) was lost in a crash after flutter caused by a separated elevator trim from the tailplane. The pilot ejected safely.

After acquiring the prototype and design rights for the Turbo Mustang III from Cavalier in November of that same year, Piper Aircraft was able to obtain the turboprop engine that Cavalier failed to obtain: the 2455hp Lycoming T55-L-9.

The prototype performed well in the Pave Coin tests and its performance was confirmed by the USAF. However, the USAF did not show very much interest for the project and Piper failed to obtain an Air Force contract.

For the next eight years, Piper and Lindsay repeatedly lobbied Congress to force the USAF to officialy re-evaluate the Enforcer. Eventually, their perseverance paid off: in September of 1981, after pressure from Congress, Piper received a $11.9 million contract to build two new prototypes to be tested and evaluated by the USAF.

The Enforcer never was in the Air Force inventory and as such was never given an official military designation or serial number. It carried the Piper designation PA-48 en civilian registration numbers.

PA-48 Enforcer N481PE (Photo by USAF)
Above & below: N481PE, one of 2 PA-48 Enforcer prototypes. Clearly visible are the turboprop exhaust, wingtip fuel tanks and underwing hardpoints.

PA-48 Enforcer N481PE (Photo by USAF)

The PA-48 Enforcer showed some resemblance with a Mustang but had in fact little in common with the original P-51 (it shared less than 10% of their structure with the P-51). They were essentially a completely new, bigger and meaner looking aircraft. Some of the biggest changes in the design were:

  • It was a single seat aircraft

  • A 2,455hp T55-L-9 turboprop engine was installed

  • The belly scoop was completely removed and a large turboprop exhaust was fitted on the left-hand side of the fuselage, just ahead of the cockpit. The exhaust was masked by the wing to reduce infrared signature and was carefully canted to counter the torque from the propeller.

  • The airframe was 15” (38 centimeters) longer

  • A bigger tail

  • A four-bladed paddle propeller

  • Plastic armor

  • Self sealing fuel tanks

  • A total of 10 underwing stores pylons

  • Provisions for wingtip fuel tanks

  • No built-in armament in the wings, guns would be carried in external gun pods

  • An Yankee rocket ejection seat

The first prototype (N481PE) took to the skies on April 9th, 1983. The second followed soon after on July 8th, 1983.

The USAF did evaluate the Enforcer, but again to no avail. Both prototypes were again found to perform well in the role they were designed for, but the Air Force did not decide to purchase any further PA-48s and eventually the project died. Both prototypes were put in storage by the USAF in late 1986.

Both PA-48 Enforcer prototypes (Photo courtesy of Michael O'Leary)
Above: both PA-48 prototypes N481PE and N482PE on the ramp of Edwards AFB.

Both PA-48 Enforcers still exist today: N482PE is awaiting restoration at Edwards AFB and N481PE has been fully restored and resides in the “Prototype Hangar” at the National Museum of the USAF at Wright Patterson AFB.

Of the Cavalier Mustang, several airframes still fly today.

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