The P-51 Mustang Down Under

Dec 24, 20247 min read

Updated: Dec 29, 2024

Much has been recorded about the North American P-51 Mustang, from it being designed in response to a Royal Air Force (RAF) specification, to its ability to escort long range bombing missions into the heart of Germany and its excellent handling characteristics. However, perhaps less-well-known is the Mustang’s extensive service with the Royal Australian Air Force (RAAF) and how Australia- a country that, before 1936, had virtually no aircraft industry - became the only nation outside of the United States to build the Mustang under license. Read on as we explore this story and how Australia managed to build one of the most advanced piston-engine aircraft of its time.

The Search for a New Fighter:

The search to replace Australia’s main fighter aircraft, the Curtis P-40 Kittyhawk, began in 1942. By the end of the year, it was clear that the P-40 was no longer competitive against contemporary allied and enemy fighters. Australia needed to begin looking for a new modern fighter for production within Australia. In early 1943, a mission was sent overseas to America and the United Kingdom to select both a new fighter aircraft and a new bomber aircraft for production back home. The mission was led by Daniel McVey, then at the time Secretary of the Department of Aircraft Production (DAP), and included Lawrence Wackett (General Manager of the Commonwealth Aircraft Corporation (CAC)) and representatives from the RAAF. They would consider four options:

An improved version of the P-40 Kittyhawk.
The P-47 Thunderbolt
The Spitfire
The P-51 Mustang.

Ultimately, selection was narrowed down to the Spitfire and the Mustang. The mission was unable to come to a final decision until a meeting with Air Marshal Sir Ralph Sorley of the RAF, who recommended the Mustang over the Spitfire. As such the mission agreed to recommend the Mustang as the next production fighter for Australia.

Why the Mustang?

Wackett was a key advocate for the Mustang over the Spitfire citing its superior speed, greater range (a critical requirement for the RAAF), and ability to carry bombs, rockets, fuel tanks, and other stores. Furthermore, overall it was an easier aircraft to manufacture. Australian Mustangs would be built and assembled by the Commonwealth Aircraft Corporation, and be powered by the Packard merlin engine. The engines were both imported as well as built by CAC at their Lidcombe plant.

Mustangs of No.84 squadron in formation — Mustang's of No.84 Squadron in formation - 27/07/1945. Source: Australian War Memorial

Mustang Production in Australia:

The original production requirement was for 690 aircraft, with deliveries planned for the beginning of 1944. Delays did transpire and it wasn’t until late 1944 that a P-51D Mustang was delivered to Australia as a pattern aircraft. The first 80 Mustangs, designated CA-17 Mustang Mk.20, were assembled from imported components. The first CAC built Mustang took to the air for the first time on the 30th of April 1945. However by now the original order had already been altered to 350 locally produced machines, supplemented by 285 P-51D’s and Ks were to be imported from the United States.

Imported Mustang’s began arriving in April 1945, with all 297 arriving by September. These included 83 P-51Ks (delivered between April and August) and 214 P-51D’s (delivered between May and September). The P-51D and P-51K differed only in the propeller that was fitted, and many that were imported into Australia were equipped to carry four 5inch rockets underneath their wings. Many of these imported Mustangs were sent directly to storage.

As the Second World War came to an end, and the need for fighter aircraft significantly diminishing, the order with the CAC was further cut to 200 machines. By VJ Day, only 15 Mustang’s had come off the CAC’s production line and delivered to the Royal Australian Air Force. The first 80 CA-17 Mustang Mk.20’s had all been delivered by July 1946. A second batch of 170 aircraft was placed in late 1946, although this was cut to only 120 and were built in a variety of configurations. This order was designated CA-18 by the CAC although the order covered a few different variants.

The first 14, originally planned as Mk.21, were modified for photo reconnaissance with the addition of cameras and known as Mustang Mk.22’s. All but one were handed over to the RAAF between July and August 1947. The last one was kept for testing and trials and was not delivered until April 1949.
26 Mk.21 arrived between August 1947 and July 1948.
66 Mk.23 with upgraded British built Merlin 70 for improved high-altitude performance.
Another 14 Mk.22PR’s, produced between October 1950 and August 1951.

The final CAC Mustang was delivered to the Royal Australian Air Force on the 3rd of August 1951. Production for the final aircraft was deliberately kept slow in order to keep CAC in work while the next aircraft for production was chosen.

Two mustangs on the tarmac at fishermens bend — Two Mustangs on the tarmac at Fishermens Bend. On the left is CAC mustang A68-1. Source: Australian War Memorial.

Operational Service:

The RAAF’s first Mustangs were American built Mustangs and operated by No.3 Squadron in Italy from 1944. Domestically the first squadrons to re-equip with Mustang were Nos. 84 and 86 Squadrons based at Townsville, Queensland. Both squadrons were equipped with imported P-51d’s and P-51ks, with the first arriving to No.84 Squadron at the beginning of June 1945, while 86 Squadron received their first in July. It was planned that both squadrons would relocate to Labuan, Borneo to join No.78 Wing. However Japan’s surrender on the 15th of August 1945, and with it the end of the Second World War, meant that this never occurred. Training still occurred until both units were disbanded, 84 Squadron on the 20th of December 1945 and 86 Squadron on the 29th of January 1946.

Nos. 76,77 and 82 Squadrons of No.81 Wing were next reequipped with the Mustang. Following the end of the war No.81 Wing was earmarked to deploy to Japan as part of Australia’s contribution to the British Commonwealth Occupation Force (BCOF) and as such in September 1945 Nos. 76, 77 and 82 Squadrons began to re-equip with P-51Ds. They were only equipped with P-51Ds to help simplify logistics and supply issues with the United States Army Air Force. By February 1946, all three squadrons were ready to deploy, and between the end of February and the end of March 1946, the Mustangs were flown from Labuan, Borneo to Iwakuni, Japan, and shortly thereafter to Bofu. Throughout their deployment in Japan the squadrons were tasked with undertaking surveillance flights. During 1948, as the Australian government started to reduce the Australian military presence in Japan, it was decided to disband No.81 Wing, and thus disband Nos. 76,77 and 82 Squadrons. Nos. 76 and 82 Squadrons were disbanded in October of that year, but the disbandment of No.77 Squadron was delayed. Eventually, in June 1950, No.77 Squadron received orders to return home, and the last routine flight was conducted on the 23rd of June 1950.

Mustangs of flight line — Mustangs of No.82 Squadron at Bofu, Japan. Circa.1947 Source: Australian War Memorial

The Korean War:

On June 25th, 1950, North Korea invaded South Korea and with it the Korean War began. Immediately No.77 Squadron orders to return back to Australia were cancelled, and they began preparations for combat flying. By June 29, the squadron was under the command of the Fifth Air Force of the United States Air Force. On the 2nd of July, the squadron undertook its first operations, escorting Dakotas that were flying out the wounded and escorting B-26 and B-29 bombers on an offensive bombing mission. This was followed the next day with their first ground strike mission against enemy targets. By the end of July 77 Squadron had undertaken 280 sorties that consisted of a mixture of ground attack and escorting duties. By the end of August the squadron had laid claim to 35 tanks, 212 trucks and other vehicles, 4 locomotives, 14 box cars and 15 fuel or ammunition dumps being destroyed. As UN forces pushed north, on the 12th of October, the unit was moved from Japan to Pohang in South Korea, allowing themselves to get closer to targets. In early 1951, Mustangs built at CAC started arriving in Korea, however only a handful of these would arrive as by April 1951 77 Squadron was back in Japan and re-arming with the Gloster Meteor jet fighter. By the end of the month Mustang operations had stopped. Between July 1950 and April 1951 the Mustangs of No.77 Squadron had flown over 3200 sorties.

Mustang being armed for battle — A Mustang of No.77 Squadron being armed for battle. Source: Australian War Memorial

Domestic use:

Back in Australia a handful of other units also took charge of Mustangs. In March 1947 No.4 Squadron became the first RAAF unit to receive CAC-built Mustangs, taking delivery of a batch of CA-17 Mustangs Mk.20s. The unit was renamed No.3 Squadron in March 1948, and by early 1952 operations on the Mustang came to an end, although the unit flew a single Mustang until June 1953. No.75 Squadron also had a brief stint with the Mustang, re-equipping with the type in July 1946 before being disbanded on the 28th of March 1948. No. 76 Squadron, afters its disbandment in Japan, was reformed in January 1949 and flew CA-18 Mustang Mk.23 until they converted to De Havilland Vampires in June 1952. No.78 Squadron flew CA-17 Mustang Mk.20s until being disbanded in April 1948.

Training squadrons also utilized the mustangs. Notably, No.2 Operational Training Unit, based at Mildura, Victoria, used Mustangs for training fighter pilots between July 1945 until the until the unit was disbanded in March 1945. The unit was reformed in 1952, utilizing CAC Mustangs for fighter pilot training before flying activities ceased in 1956.

The final RAAF squadrons to fly the mustang were five squadrons of the Citizen Air Force (active reserves squadrons). These were Nos. 21 (City of Melbourne), 22 (City of Sydney), 23 (City of Brisbane), 24 (City of Adelaide) and 25 (City of Perth) Squadrons. During 1955-56 all but No.24 Squadron transitioned from the Mustang to De Havilland Vampires. No.24 Squadron continued flying Mustangs until all Citizen Air Force squadrons were disbanded in 1960. The disbandment of No.24 Squadron would also mark the end of the Mustang’s career with the RAAF having accumulated some 109,000 flying hours while in service. In total 298 P-51d and K were imported from America, complemented by 200 built by CAC.

The RAAF also accepted deliveries of Mustangs from America for the Netherlands East Indies Air Force.

Today a number of CAC built Mustangs exist in a range of forms from flying status to static display, to under restoration. While mainly found in Australia, they can also be seen in America and the United Kingdom.