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[Fresco23]

Hi all! This was originally intended to be a serious request but i am having a very difficult time finding relevant info. I cant find a blueprint and had a hard time getting a half way descent 3view, but the idea is cool i think so i will go ahead and toss it out here in case anyone is interested. If admins take it down, i understand, but know that i intend to update the info if i can find a better source than wiki... Here it is for now.



General characteristics
 Crew: 1
 Length: 51 ft 5 in (15.67 m)
 Wingspan: 33 ft 5 in (10.18 m)
 Height: 15 ft 4 in (4.67 m)
 Wing area: 30.75 m ()
 Empty weight: 17,892 lb (8,132 kg)
 Loaded weight: 27,046 lb (12,293 kg)
 Powerplant: 1 × Allison XT40-A-1 turboprop, 5,850 hp (4,365 kw)
 
Performance
 Maximum speed: 520 mph (837 km/h)
 Range: >2,000 mi (3,200 km)
 Service ceiling: >40,000 ft (14,600 m)
 Rate of climb: 5,000 ft/min (1,520 m/min)
 Thrust/weight: 0.66

The XF-84H was created by modifying a F-84F airframe, installing a 5,850 hp (4,360 kW) Allison XT40-A-1 turboprop engine[6] in a centrally-located housing behind the cockpit with a long extension shaft to the nose-mounted propeller.[7] The turbine engine also provided thrust through its exhaust; an afterburner which could further increase power to 7,230 hp (5,391 kW), was installed but never used.[8] Thrust was adjusted by changing the blade pitch of the 12 ft (3.7 m)-diameter Aeroproducts propeller, consisting of three steel, square-tipped blades turning at a constant speed, with the tips traveling at approximately Mach 1.18. To counter the propeller's torque and "P-factor", the XF-84H was fitted with a fixed dorsal yaw vane.[9] The tail was changed to a T-tail to avoid turbulent airflow flow over the horizontal stabilizer/elevator surfaces from propeller wash.[

The XF-84H was quite possibly the loudest aircraft ever built (rivalled only by the Russian Tupolev Tu-95 "Bear" bomber [13]), earning the nickname "Thunderscreech" as well as the "Mighty Ear Banger".[14] On the ground "run ups", the prototypes could reportedly be heard 25 miles (40 km) away.[15] Unlike standard propellers that turn at subsonic speeds, the outer 24–30 inches of the blades on the XF-84H's propeller traveled faster than the speed of sound even at idle thrust, producing a continuous visible sonic boom that radiated laterally from the propellers for hundreds of yards. The shock wave was actually powerful enough to knock a man down; an unfortunate crew chief who was inside a nearby C-47 was severely incapacitated during a 30-minute ground run.[15] Coupled with the already considerable noise from the subsonic aspect of the propeller and the dual turbines, the aircraft was notorious for inducing severe nausea and headaches among ground crews.[

more pics including an 3 view that i managed to stumble across sorry the first 3 view is enormous

xf84h by Fresco 23, on Flickr

[warhawk]

Try here for blueprints 

[Sleepingdragon]

I recommend resizing that drawing in any photo program so it can be more easily seen. 

While this is an interresting project (one I remember from decades ago), I think we are hoping for an actual F-84F, though there is a hack running around. It would probably be much more likely to develope after an F shows up. I keep seeing rumors of an F, but ........................maybe someday.

This is one of those goofy ideas somebody came that wound up just swallowing lots of the defense budget, like the Convair seaplane fighter based on the F-102, and those vertical take-off jobs in the days before computers that almost impossible to control. Sure is a good looking thing though. kinda wonder why they thought they needed a turbo prop fighter when jets were making such progress. Is why there's lots of small memorials to test pilots. I wonder if there is any surviving film of it flying.

[zdragon]

I wonder how they would make the engine sound.  The tips of the props were traveling at the speed of sound and the plane was one of the noisiest in the world short of the Russian TU-95 which has 8 props that break the speed of sound (counter rotating)  I remember watching a show that said the bear could be heard by underwater acoustic devices that were intended to listen for subs because it was so loud.  I would imagine the Thunderscreech would be almost as loud.

i found a small youtube clip of the thunderscreech:
i found it enlightening hope you guys do too.

[VF111Sundowner]

kinda wonder why they thought they needed a turbo prop fighter when jets were making such progress.

They wanted the acceleration of a prop driven fighter with the top speed of a jet.

[(-battlemaster-)]

is this the pre-asasor of the F-104? look a like

[Fresco23]

I recommend resizing that drawing in any photo program so it can be more easily seen. 

While this is an interresting project (one I remember from decades ago), I think we are hoping for an actual F-84F, though there is a hack running around. It would probably be much more likely to develope after an F shows up. I keep seeing rumors of an F, but ........................maybe someday.

This is one of those goofy ideas somebody came that wound up just swallowing lots of the defense budget, like the Convair seaplane fighter based on the F-102, and those vertical take-off jobs in the days before computers that almost impossible to control. Sure is a good looking thing though. kinda wonder why they thought they needed a turbo prop fighter when jets were making such progress. Is why there's lots of small memorials to test pilots. I wonder if there is any surviving film of it flying.

Ill try and resize the 3view. And i agree: an "actual" F-84F would be awesome as well, and it makes sence that that might coome first. However i still think this aircraft is rediculously interesting in and of itself. Its one of those few that i cant really say why it caught my eye, it certainly isnt pretty(at least my opinion), but for some reason, i like it anyway! lol

[VF111Sundowner]

is this the pre-asasor of the F-104? look a like

Not really the look may be the same but its an entirly differnt method of thinking.

Lockheed under kelly Johnson designed and built the F-104 to be a highspeed interceptor,

Republic built the "Thunder" family of aircraft. This aircraft is the A-10's great uncle twice removed.

Incedently the T-tail arange ment is not the best for a fighter or aircraft expected to manuvere a great deal. as higher angles of attack are reach the main wing destroys airflow of the tail reducing the effectivness of the elevators.

[mikoyan99]

I could have a go at a "Franken" if you like. I'd have to use the flight model from a conventional piston engined fighter, it probably wouldn't be as fast the real thing, but that could be sorted.

[ton414]

I'd have to use the flight model from a conventional piston engined fighter, it probably wouldn't be as fast the real thing, but that could be sorted.

You can use a jet engine, don´t you know the PA-48 Enforcer models?, and piston models you can do almost as fast as you want, don´t  you know the Spitfire XIV CRP?.

[VF111Sundowner]

I have a question, as looking at the design again.

Where would they mount the armaments?

The original F-84 had four .50s on the top of the nose above the inlet and two in the wing roots.

While the RF-84 had four .50s for self defense located below the wing inlets. Now they can place them there on this aircraft but I feel there would be problems getting the rounds past the propeller arc.  A fire interruptor yes but that was used for sub sonic props and slower rate of fire guns.

Any thoughts?

[Fresco23]

I cant find it at the moment but i believe i saw somewhere that it was to be nose guns on the -84H as well but the prototypes were never armed because they were still working out how to fire the canon through such a fast propellor.

and actually according to one source it did have a jet engine of sorts... Wiki:
The turbine engine also provided thrust through its exhaust; an afterburner which could further increase power to 7,230 hp (5,391 kW), was installed but never used.
although, not sure where that info comes from on wiki....

Also aparently no one knows the "actual" top speed. Wiki, aside from what ive seen, states:
Although The Guinness Book of Records recorded the XF-84H as the fastest propeller-driven aircraft ever built,[18] with a design top speed of 670 mph (1,080 km/h) (Mach 0.9) and 623 mph (1,003 km/h) (Mach 0.83) during tests, this claim has been disputed.[11] The unofficial record speed is also inconsistent with data from the National Museum of the United States Air Force, which gives a top speed of 520 mph (840 km/h) (Mach 0.70), nonetheless, making the XF-84H the fastest single-engine propeller-driven aircraft[10] until 1989 when "Rare Bear", a highly modified Grumman F8F Bearcat reached 528 mph (850 km/h) (Mach 0.71).