Proposed Super Furies
F2J
The designation was never officially made by the Navy, but two North American proposals (three if you count the "FJ-5") could have resulted in an F2J. The first was in the OS-130 competition. Like the winning Vought design, it featured a two-position variable incidence wing.
George Spangenberg wrote that it came in a close second and lost primarily because North American projected that the gross weight of its J57-powered proposal was almost 30,000 lbs, considerably more than the Vought proposal's with the same engine. Spangenberg correctly predicted that the Vought weight was optimistic, but would still be less than the North American design and therefore provide better performance.
Thanks to Doug Siegfried at Hook magazine for the artist's concept and to Tony Buttler for the three-view. (Note: the three-view is the J65-powered proposal; like Vought and most of the other offerers, North American submitted both J65 and J57-powered proposals.)
In November 1953, North American tried to end run the F8U program with a Super Fury proposal, which was a carrier-based derivative of the J57-powered F-100B (stretched fuselage, wing flaps, etc.) being proposed to the Air Force. The F-100B was a redesign of the J57-powered F-100A that incorporated the latest supersonic flight technology and almost doubled the internal fuel capacity. The inlet was now swept back and incorporated variable geometry, with a horizontal ramp on the upper side used to establish and control the shock wave associated with supersonic flight. Unlike the F-100A, the fuselage was to be area ruled for improved transonic performance and lower supersonic drag. It had also been lengthened by almost four feet to increase its fineness ratio and add more fuel. The wing was basically the same in shape and area, but it was thinner and designed to hold fuel. Flaps were added and boundary layer control incorporated for slower takeoff and landing speeds. The main landing gear now featured dual wheels.
For the Super Fury proposal, in addition to adding the requisite tail hook, wing folding, catapult hooks, etc., other changes were made to the F-100B design to further improve the prospect of carrier suitability. When the flaps were lowered, the folding portion of the wings was repositioned to provide 15 degrees of anhedral to improve lateral stability and aileron control at low speeds. The fuselage speed brake was intended to be deployed on approach and would retract automatically on touchdown. Another innovation was a retractable gun sight to improve over the nose visibility.
North American chose to propose armament of three T-160 20 mm cannons. Dual rotating rocket launchers contained 44 two-inch folding fin rockets could be substituted for the guns. One feature from the F-100B design was an alternative forward fuselage that incorporated a radome housing a small search radar in place of the APG-30 ranging radar.
Although it had the same engine and equipment, the Super Fury was heavier than Crusader so it would also have cost somewhat more. Although shorter, only 22 could be spotted in the requisite deck space compared to 25 F8Us . The Super Fury proposal was also deficient in military power ceiling. However, it was projected to be slightly better than just supersonic on military power, faster than required on combat power, have considerably more range on internal fuel and external fuel, and otherwise meet or exceed the requirements.
The proposal’s most compelling feature was that a prototype of sorts was flying and first Super Fury production delivery was expected in early 1956 on that basis. As it turned out, the Air Force decided not to proceed with the F-100B (although it did seque into the F-107) and the Vought F8U Crusader was a success.
FJ-5
Both Grumman and North American had previously gotten contracts from the Navy for new day fighters - the original F9F-8 (then F9F-9, then F11F-1) and FJ-4 respectively - using the funds provided to the F9F-6/7 and FJ-3 production contracts for product improvements. Both were powered by the Wright J65, the same as the FJ-3 and A4D. In accordance with the vision of the then Fighter Class Desk officer, the FJ-4 did not have an afterburner and was optimized for low cost of acquisition and operation. It was, however, to be a great dog fighter, with excellent maneuverability at altitude and near-sonic speed and did in fact achieve those goals. Grumman managed to get an afterburner on the F11F but it was a new Wright design and disappointed in thrust and therefore supersonic performance.
Against all comers, Vought had won the competitive day fighter contract in accordance with a new specification that required an afterburner. Both J65 and J57-powered designs were proposed, with the Navy selecting the higher performance J57 design. At this point, Grumman and to an even greater degree, North American, were in a disadvantageous position if the J57 turned out to be as good as expected and the Crusader met Vought's performance projections.
Both Grumman and North American then turned to the new General Electric J79 engine which was not available for the competitors to consider for the 1952 day fighter proposals in futile attempts to provide an attractive alternative to the F8U. Grumman apparently got to the Navy first and/or best, since BuAer began planning to buy a J79-powered F11F Super Tiger as the F12F. (One more time, the F12F was not the Grumman Design 118.) Unfortunately for Grumman, the XF8U went supersonic on its first flight in March 1955 and the F12F plan was dropped. However, BuAer did contract with Grumman for two J79-powered F11F-1Fs because they wanted to get some flight experience on the J79 before the F4H flew with it. Grumman was still hopeful that Vought would stumble with the F8U and/or the F11F-1F would be good enough to reinstate a Navy production program and/or be of interest to foreign buyers. North American's proposal didn't even get that far. Vought, of course, didn't stumble. The F8U was even faster than they guaranteed.
Strictly speaking, the "FJ-5" wasn't a navalized F-107, which was powered by the bigger J75. The FJ-5 had a gross weight of about 20,000 pounds and the F-107, 40,000 pounds. The two roughly compared like the Crusader I and the Crusader III. The FJ-5 had a bigger wing relative to its weight since it had to takeoff and land from aircraft carriers while the F-107, like the F-105, was to be flown from mile+ long runways. The designation doesn't appear to have been officially applied.