I guess you're all familiar with the Vought A-7 Corsair aka SLUF. But how would it look without the characteristic chin intake? Here my take: The GAF Corsair II....
For the RAAF the search for a Sabre replacement began in the late 1950s, and when a joint evaluation team from the Departments of Air and Supply visited Europe and North America in the early 60-ies. During this process the RAAF evaluated the Dassault Mirage III, Dassault Mirage 5, Northrop F-5, McDonnell Douglas F-4 Phantom II, Lockheed F-104 Starfighter and the SAAB J-35 Draken before finally selecting the Corsair II in 1968.
Like the US government the Australian Government insisted to search for a multirole (in the anti-ship, air interdiction and air defense roles) aircraft as a replacement for the CAC Sabre fighters. The anti-ship role required an aircraft to be efficient in low altitude while the air interdiction and air defense roles required a high altitude efficient aircraft. While the lessons learned in the deployment of Canberra's in Vietnam conflict (The Canberra's were typically operated in the low-level bombing role)dictated an high altitude interdiction and defense role would likely change in the near future to mid to low altitude interception. This changed the requirements and all agreed an multirole subsonic fighter with supersonic and strike capabilities. The Vought A-7 seemed to be a relatively quick and inexpensive way to satisfy this need.
Built by the Ling-Temco-Vought, the YA-7A made its first flight on 27 September 1965. After several trails the A-7A and B versions were suited unfit for the Australian joint evaluation team as pilots noted a lack of engine thrust. This was later addressed with the A-7D/E.
Although it was recognized the turbofan engine provided a dramatic increase in fuel efficiency compared with earlier turbojets.
During 1966 the Australian joint evaluation team got interested in the A-7D (then under development for the USAF TAC) and in 1967 the decision was made to keep the Avon Sabres as the main fighter until a suitable replacement was available. The A-7D differed from the Navy's Corsair II in several ways. For one, the Air Force insisted on significantly more power for its Corsair II version, and it selected the Allison TF41-A-1 turbofan engine, which was a license-built version of the Rolls-Royce Spey. It offered a thrust of 14,500 pounds, over 2000 pounds greater than that of the TF30 that powered the Navy's Corsair IIs. Other changes included a head-up display, a new avionics package, and an M61A1 rotary cannon in place of the two single-barreled 20-mm cannon. Also included was a computerized navigation/weapons delivery system with AN/APQ-126 radar and a head-up display. The first Spey-powered A-7D (67-14854) flew for the first time on 26 September 1968.
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Meanwhile the Australian joint evaluation team contacted Rolls-Royce about the availability of the the afterburning Spey 201 then selected for the Blackburn Buccaneer S2 and F-4K/M as the A-7D was designed for subsonic speeds (Spey 201 turbofans: 12,250 lb thrust dry and 20,515 lb thrust with afterburner). Partly as a means of guaranteeing employment in the Australian aerospace industry, agreement was reached in 1968 that major portions of the RAAF's Corsairs would be built domestically. The A-7D variant was taken as the basis for the RAAF aircraft, subject to major redesign.
The most significant change was the substitution of the larger and more powerful afterburning Rolls-Royce Spey turbofan to allow supersonic interceptions.
GAF redesigned and built the entire lower fuselage section with area rule as CAC earlier did with the Avon Sabres. This redesign meant about 50% of the original airframe was changed and the inner hardpoints onthe A-7 wings couldn't be used.
Initially, there was an intention to procure up to 200 aircraft for the RAAF, but the development cost for the changes to accommodate the Spey turbofans meant that the per-unit price eventually ended up three times the price of an A-7D. Because the government then had a policy of negotiating fixed-price contracts, these costs could not be evened out by a large production run, which left the total order at 83.Pilots of the GAF Corsair II lauded the aircraft for general ease of flying (with the exceptions of poor stability on crosswind landings) and excellent forward visibility. The aircraft ceased squadron operations in September 1985.
Pictured is a No 3 Squadron aircraft stationed at Butterworth in 1969.