The Demon: Another 1950’s Design Shackled With a Poor Performing Engine

Lead Sled Was Not McDonnell’s Favorite Moniker for Their First Swept Wing Fighter

F3H-2N via US Navy

As Tim the Tool Man Taylor might quip, this thing would be better with more power. McDonnell’s F3H Demon fighter jet was intended to replace the previous F2H Banshee, which was a replacement for the McDonnell FH Phantom. The F4H Phantom II was the next and last McDonnell design before the merger with Douglas and drew heavily on the Demon’s design. We all know how that turned out! The Demon was developed in the days of inadequate jet engine thrust, and it paid the ultimate price for the timing of its development. The Demon was in service with the United States Navy for only eight years, between 1956 and 1964. To understand the Demon, one must go all the way back to 1949.

F3H-2 via US Navy

Ironically the Demon’s primary competition for a contract during development was the Douglas F4D Skyray. The Skyray (when powered by the Pratt & Whitney J57 engine) outperformed the Demon and was a delta winged design capable of Mach 1 speed in level flight. The Demon was the first McDonnell fighter design drawn with swept wings from its inception as opposed to being designed with straight wings and adapted for swept wings later. Like every aerospace contractor building jets for the military in those days, McDonnell just couldn’t find enough get up and go in the thrust department for the F3H.

F3H-1N via US Navy

Initially the Demon was powered by a single Westinghouse J40 engine. This was a design departure for McDonnell as all of their previous fighter products for the Navy were powered by twin engines. In single engine fighter designs that single engine must be powerful, reliable, and relatively economical. The J40 was none of those things. The J40 was the same engine Douglas tried to power their twin engine A3D Skywarrior for the Navy. Words like disastrous, abysmal, calamitous, dreadful, and unfortunately fatal have been used to describe the J40. The Skywarrior ended up with Pratt & Whitney J57 engines and went on to make history. The Demon…well, not so much.

F3H-1N via US Navy

Douglas experienced a similar problem with the Skyray but overcame it by powering the F4D with the J57. The engine chosen to power the F3H was not entirely up to McDonnell. The Navy specified the J40 for the Demon. At the time, the Navy had nothing with which to counter the Mikoyan-Gurevich MiG-15. In fact the Navy was so concerned about the MiG-15 that they decided to award a contract for the F3H-1N even before the XF3H-1 flew for the first time- powered by a J40 engine, during August of 1951. The Navy went so far as to award a contract to Temco in Dallas to license build an additional 100 Demons. Operational Demons did not begin evaluation until January of 1953. And those evaluations were deadly.

XF3H-1 via US Navy

Eight of the 60 early production F3H-1N aircraft powered by the J40 engine were involved in Class A (read really bad or total loss) mishaps. 25 of them never even got off the ground. The aircraft were grounded entirely when the tote board got to six aircraft totally destroyed and four pilots killed. The remaining F3H-1N Demon airframes were ingnominiously relegated to being taken apart and put back together at technical training schools for airframe mechanics and other maintainers.  A proposed F3H-1P photo reconnaissance variant, also to be powered by the J40 engine, was cancelled outright. Finally and mercifully in 1955 the J40 program was discontinued.

F3H via US Navy

So where did that leave the Demon? The best engine solution available at the time was the J57. Hands down. But J57s were too big to fit into the F3H’s fuselage without major surgery. The replacement for the J40 ended up being the Allison J71-A-2- the same engine that (under) powered the Douglas B-66 Destroyer for the Air Force. Demons powered by J71 engines were designated F3H-2N. These were no trusty steeds either, experiencing not only engine reliability problems (flameouts and compressor stalls), but also ejection seat reliability problems. The F3H-2N, first flown in 1954, was plagued by engine problems for its entire existence. Fortunately the adoption of the Mart-Baker Mark 4 ejection seat largely resolved the seat reliability issues.

F3H-2N via US Navy

The F3H-2N gained operational status during November of 1956. Initially armed with four 20 millimeter cannons, it became common practice to remove two of them to save weight when carrying ordnance. The F3H-2M variant was capable of firing the Raytheon AAM-N-2 Sparrow radar guidedair to air missile. Later the AAM-N-7 Sidewinder heat-seeking air to air missile was added to the Demon’s quiver. The initial radar system (AN/APG-51) was incrementally improved over the course of the F3H-2M’s service. The F3H-2 retained the ability to launch missiles but was the fighter-bomber version of the Demon, equipped with a 17% larger wing and capable of hauling a 6,000 pound payload.

F3H-2M via US Navy

The common design characteristics across all variants of the Demon were a single-engine turbojet powered all weather fighter aircraft featuring side-mounted engine air intakes and swept low mounted wings and empennage. The wings had full-span leading edge slats and a large one-piece flap, conventional ailerons, and wing fences adjacent to the ailerons. The aircraft’s hydraulic system was used for the Demon’s folding wings and for the fuselage mounted airbrakes located on both sides of the fuselage aft of the wing trailing edge. A retractable refueling probe was mounted on the starboard side adjacent to the cockpit. The horizontal stabilizers/elevators were all-moving, and the vertical stabilizer had a conventional rudder. The vertical stabilizer was mounted aft on an extended tailcone shaped like a duck tail that was a distinctive feature of the Demon.

F3H refueling from AD via US Navy

The Demon was the first fighter to have no mechanical backup for its hydraulically operated control surfaces. The jet was equipped with a ram air hydraulic pump to power a small emergency-only hydraulic system. The system was only usable at high speeds. Even after the J71 engine was adopted, the F3H was underpowered. One anecdote claims that on a hot day at mile-high Kirtland Air Force Base (AFB) near Albuquerque in New Mexico, calculations for an F3H takeoff roll at military power indicated a required distance of infinity- not good when there are “only” 15,000 feet of available runway! Aviators appreciated the Demon’s handling qualities at altitude…but they had to get there first.

F3H-2M via US Navy

In 1960 the last of 519 Demons rolled off the production line. In 1962 the designation system changes turned the F3H series into the F-3. The F2H-2N was redesignated F-3C, the F3H-2 was redesignated F-3B, and the F3H-2M became the MF-3B. Demons were operated exclusively by nine Atlantic Fleet and 15 Pacific Fleet fighter squadrons along with Composite Squadron THREE (VC-3), Air Test and Evaluation Squadron THREE (VX-3) and VX-4. Fighter Squadron ONE FOUR (VF-14) Tophatters took the F3H-2N to sea for the first time during a deployment with Carrier Air Wing ONE (CVW-1) embarked on the carrier USS Forrestal (CV-59). The jets fit into a niche between the Vought F-8 Crusader and Grumman F11F Tiger as the all-weather missile-armed interceptor of the fleet.

F-3s via US Navy

The last operational F-3s were removed from service when Fighter Squadron ONE SIX ONE (VF-161) Chargers traded up to the next McDonnell product- the F-4B Phantom II in 1964. Ironically an F3H-2N was adapted for use as a development airframe for the AN/APQ-50 radar system- the very same one used in the F-4B. In service the jets were occasionally referred to as The Chair due to the design’s excellent visibility for the pilot. F-3 pilots were known as Demon Drivers and their maintainers were known as Demon Doctors. Inevitably the aircraft also picked up a nickname referring to its lack of thrust- the Lead Sled or just Sled.

F-3B retirement ceremony via US Navy

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Bill Walton

Written by Bill Walton

Bill Walton is a life-long aviation enthusiast and expert in aircraft recognition. As a teenager Bill helped his engineer father build an award-winning T-18 homebuilt airplane in their Wisconsin basement. Bill is a freelance writer, an avid sailor, engineer, announcer, husband, father, uncle, mentor, coach, and Navy veteran. Bill lives north of Houston TX with his wife and son under the approach path to KDWH runway 17R, which means they get to look up at a lot of airplanes. A very good thing.

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