FJ Furies

28 October 2016: For some more notes on the FJ-4/4B, see http://tailspintopics.blogspot.com/2016/10/north-american-fj-44b-fury-notes.html

Summary

This will be a work in progress for some time as I add information to it. For starters, North American produced several different Furies for the Navy:

FJ-1: Straight wing early jet

XFJ-2: Minimal modification of the USAF F-86E/F Sabre to expedite evaluation and qualification of a carrier-based derivative. One was configured with the Navy’s four-20 mm cannon armament; two were unarmed but capable of carrier takeoffs and landings.

FJ-2: Production swept-wing design based on the F-86 and powered by its J47 engine.

FJ-3: FJ-2 redesigned for the more powerful Wright J65 engine.

FJ-4: Complete redesign of the FJ-3 airframe for longer range, better endurance, and better altitude performance and maneuverability but retaining the Wright J65 engine.

FJ-4B: FJ-4 modified for the jet attack mission.

Other "Fury" proposals: There were also at least three serious proposals for follow-on programs: A variable-incidence, two-position wing for the OS-130 proposal that Vought won with what became the F8U-1 Crusader; a carrier-based variant of the F-100B, which had been proposed to the USAF but was not produced; and a down-sized version of the USAF F-107 that was powered by the General Electric J79 instead of the big Pratt & Whitney J57. For more, click here

FJ-1

North American proposed a jet equivalent of the P-51 Mustang to both the U,S, Navy and Air Force. Initially both versions had straight wings but the Air Force opted to take advantage of German  swept-wing research to increase the XP-86's top speed.

Only a handful of FJ-1s were built as part of the Navy's transition from propeller-driven fighters to jet-propelled fighters. It was carrier-qualified and operated by one squadron, but never deployed, reportedly due to the very short time between engine overhauls, which would have imposed an unacceptable maintenance burden at sea.

The pregnant guppy shape of the FJ-1 has led some to assume that it was powered by a centrifugal-flow engine like the F9F Panther. North American proposed two alternative power plants; the Navy chose the new GE TG-180 axial-flow engine, which was subsequently license built by first Chevrolet
and then Allison as the J35.

XFJ-2 

The two XFJ-2s had all of the carrier-basing modifications except for the folding wings and did not have any armament. They retained the F-86 inlet lines and canopy except for the windscreen, which was modified to increase the field of view forward to the side of the nose. The slatted wing of the early F-86F was used rather than the "6-3" wing of the later F-86F for better low-speed handling qualities.The single XFJ-2B was an F-86 modified with the XFJ-2 windscreen and the Navy's four 20mm cannon armament in place of the F-86E's six .50-calibre machine guns.

XFJ-2 (NA-179) BuNos 133754 and 755: Based on the F-86E but with the J47-GE-27 engine (F-86F) in lieu of J47-GE-13 (F-86E). Slatted, non-folding wing with 37’ 1’ span (ailerons extend to the wingtip). Forward and downward visibility improved by modifying the windscreen. Seat and canopy strengthened to withstand a deceleration of 40 Gs. The structure was strengthened to meet the design requirements for H-8 catapult launch and Mk 7 short-run-out arrested landing. FJ-2 landing gear, fixed catapult hook, retractable holdback and tail bumper, manually-retractable barrier guard and barrier pickup, and FJ-2-type arresting hook installed. Provisions for 200-gallon drop tanks. Cockpit rudder lock omitted and external gust lock provided. No provisions for guns, fire control or other armament equipment. The major differences from the production FJ-2 were the lack of wing folding; the smaller F-86 intake and standard F-86 canopy, except for the windscreen; and the F-86 ejection seat with the headrest positioned farther forward to support the pilot's head during a catapult launch.

 

XFJ-2 main landing gear:

XFJ-2B (NA-185) BuNo 133756: Essentially an F-86E-10 with the Navy's 20mm cannon armament and the XFJ-2 windscreen. "B" was the Navy's suffix for an armament change, which may seem odd because that installation was to be the Navy's FJ-2 armament. However, the two XFJ-2s did not have any armament at all, hence the distinction.

Note the windscreen change from the F-86 shown here:

F-86F

Note the repositioning of the pilot's headrest forward of the F-86 location.

XFJ-2

FJ-2

In addition to the carrier-basing changes introduced on the XFJ-2, the sliding canopy interface with the fuselage was redesigned, apparently to allow the pilot to sit higher while the canopy was opening or closing. The windscreen was also modified again to further increase the forward visibility. The intake was enlarged for more thrust at low speeds. The wheel track was reported increased by eight inches over the F-86, probably to provide more oleo travel for higher sink rate landings. The horizontal tail dihedral was deleted. It reportedly also had more area to provide for the longitudinal control power required when the flap travel was increased for stall speed reduction compared to the F-86.

The FJ-2s were all relegated to the USMC as being somewhat underpowered for carrier operations, although they were fully carrier capable as well as qualified. Almost all were in the experimental natural-metal scheme (see http://thanlont.blogspot.com/2009/12/it-seemed-like-good-idea-at-time-vii.html).

VMF-235 operated a few aircraft—21, 22 and 23WU—from Hancock during Project Steam in July 1954 and VMF-122 deployed aboard Coral Sea as part of CVG-17 (3XXLC) from March to September 1955.

FJ-3

Carrier-basing changes added about 1,000 lbs to the weight of the FJ-2 compared to the F-86 it was derived from. To restore performance, the more powerful J65 was substituted for the J47. To provide more air for the increased mass flow of the new engine, the intake was deepened yet again.

The only other notable external difference from the FJ-2 was the substitution of a scoop in place of the small flush NACA intake on each side of the upper aft fuselage.

In order to improve low speed handling qualities and provide more internal fuel, the FJ-3 was redesigned during production to have a fixed, extended, and cambered wing leading edge replacing the slats that were on the FJ-2 and early FJ-3 (see https://tailspintopics.blogspot.com/2011/04/fj23-fury-redux.html); this was retrofitted on the FJ-3. On BuNo 136118 and subsequent, provisions were added for two pylons on each wing inboard of the existing ones for external tanks, for a total of six. The FJ-3s were also retrofitted for inflight refueling with the installation of a fixed probe extending from the left wing.

Steve Ginter finally published his long awaited monograph on the FJ-3 to complement the ones on the FJ-1, -2, and -4.  Order it here: http://www.ginterbooks.com/NAVAL/NF88.htm. Being able to review that many pictures of FJ-3s in one place pretty much satisfied two questions that I had: 1) the blue airplanes (not counting the colorful FJ-3Ds) invariably had the slatted wing; the gray/white airplanes invariably had the hard wing with the cambered leading edge, and 2) the barrier pickup was removed from the FJ-3 but there is one picture of a gray/white airplane with it extended, so it wasn't removed as early as I suspected.

FJ-3M

An FJ-3 with provisions for Sidewinder missiles. These were invariably gray/white with the hard wing.

 

FJ-4
The significant performance improvement of the FJ-4 over the FJ-3, since they were powered by the same engine, was the redesign of the wing.

Unfortunately for North American, the BuAer fighter class desk proponent of small, simple, maneuverable fighters without afterburners left for his next assignment just after the OS-130 day fighter request for proposals was issued. The day-fighter requirement quickly shifted back to supersonic fighters and resulted in the F8U Crusader. Like the FJ-2, the FJ-4 was carrier qualified but relegated to the USMC.

FJ-4B
 The Navy contracted with North American for an attack variant of the FJ-4 to provide a backup to the A4D then under development. The FJ-4B had additional wing pylon stations, an additional pair of speed brakes for better control of speed in a high-angle attack, and small spoilers for better roll control with an asymmetric load, a Mk 7 atomic bomb under the left wing.

For maximum range, the bomb-laden FJ-4B would also carry a 150-gallon external tank on each outboard wing pylon and a 200-gallon tank on right main pylon.

When armed with Bullpup missiles, a missile-control pod was carried under the right inboard pylon.

Note the asymmetric loading with two different types of fuel tanks.

North American also developed a unique buddy refueling system that was used to maximize the strike airplane's radius of action.

The A4D proved adequate to the task and cheaper to buy and operate. The FJ-4B therefore served only in west coast attack squadrons and was eventually replaced with A4Ds.

One change that is not reflected on the otherwise excellent North American FJ-4 drawing is the span of the horizontal tail. This was subsequently* reduced to 157" by cutting off about 18 inches of the tail on each side. On the SAC drawing, the tail is correctly dimensioned but the drawing of the tail still has a bit too much span. Since model kit manufacturers most likely used the North American drawing, a check of that dimension is advised.

Early Flight Test                                                      Production

There are several kits of the Furies in both 1/72 and 1/48 scale but in 1/72 scale only the FJ-4 is represented by a complete and reasonably accurate injection-molded kit. This attractive model from that Emhar kit was built and photographed by Gordon L. Hewstone:

For useful notes on and photos of another Emhar build, see: http://www.britmodeller.com/forums/index.php?/topic/235015791-emhar-fj-4-fury-172/

The old 1/48 injection molded FJ-2/3 kit from Esci has an obviously inaccurate canopy and nose, among other shortcomings.

There are FJ-3 resin kits available in 1/72 from RVHP (which is out of production) and 1/48 from Collect-Aire.

It is, however, not very difficult to modify an F-86 kit into an XFJ-2.

*Craig Kaston reminded me of the reason why, as reported in an article by Peter Garrison in the March 2001 issue of Air&Space magazine:

"William R. Laidlaw, former chief of the Structural Dynamics Section at North American Aviation, describes in The Revolution in Structural Dynamics a similar approach to controlling stabilizer flutter in the 1950s. During a test flight, an FJ-4 Fury, a carrier-based derivative of the F-86 Sabre Jet, lost more than half of both horizontal stabilizers to a flutter incident (the pilot managed to land safely). Engineers mounted a Fury tail assembly on a rocket sled at the Navy's test facility at China Lake, California, and the flutter was duplicated. North American engineers considered various modifications to solve the problem, but finally settled on the crudest one: They sawed 12 inches off each end of the tail. A few months later, however, an FJ-4 shed its tail during a pullout from a high-speed dive, killing the pilot. The experts went back to work. They then discovered that putting a heavy load on the tail reduced its flutter margins. Another amputation, this time of a mere six inches, solved the problem for good."