Build an improved Gloster F5/34 (1 Viewer)

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fastmongrel

1st Sergeant
4,527
3,622
May 28, 2009
Lancashire
I have been following tomo pauk tomo pauk No Spitfire thread with interest and it seems to me that another British aircraft manufacturer is going to have to step up and try to build an equivalent or near equivalent to the Spitfire. It has to be British I just can't see imported or license built foreign designs being ordered or even ready to meet the Bf109 E and F.

I think the Gloster F5/34 is the most promising design. All the alternative designs come from companies that are too busy building bombers (Bristol and Vickers) too small (Miles and MB). Glosters had no projects beyond the twin engine heavy fighter which won't be missed if it's cancelled.

So starting with the F5/34 what do we need to get it up to or near 109E standard.

The engine. It has to be a Merlin nothing else comes close unless Daimler Benz suddenly start exports.

The undercarriage. That has to go what on earth was Folland doing. Maybe the Hurricane undercarriage design is used I don't think it had any problems.

The Tail. The rudder on the F5 was noted as very heavy I wonder if the forward position had anything to do with it.

The Wing. It's a one piece wing which was unusual for the time maybe design a new two piece wing.

Radiator. I believe the radiator on the Hurricane was less than optimal. What is best for the radiator I would like a P51 type but that may be too early. I think it has to be Spitfire type.

The redesigned F5 needs to be in service at the latest spring 1940. First flight of the F5 is according to Wikipedia December 1936 tests can take place in summer 1937 so the decision to rebuild the prototype has to happen late 1937. That gives Folland and his team 2 years to produce a Hurricane beater and 109E equivalent.
 
A radiator system in front of the wings would've been beneficial, since it also offers a way to decrease the thickness-to-chord. Granted, it will require Gloster to come out with that idea several years befor D-H, that might be a tall order?
For the starters - how about a simple 'beard' radiator for the 1st series? Not sexy, but gets the job done.

FWIW, the late Just Leo's profiles for the fighter (on another forum): picture
 
I really don't like chin/beard radiators but I suppose it could be used, at least it's not going to be as big and ugly as a Typhoon radiator.

The canopy looks quite good but I wonder if something like the Whirlwind or Miles M20 canopy might be possible.

The undercarriage I wonder if the Curtiss P36 style of rotating wheel gear might be useful. I don't know how it works but I imagine it's a lever and or cam that twists the wheel as the gear folds back.
 
The cooling system on the Hurricane was not particularly inefficient, and was actually more efficient than the cooling system on the Spitfire. It is only when you start to compare it to the radiators on later designs (P-51, Mosquito, etc) that it lags behind any significant amount. The only real problem with the location of the radiator on the Hurricane was that it did not allow for center-line carriage of ordnance or DTs, but since the landing gear arrangement also prevented center-line carriage it is kind of a moot point.
 
The canopy looks quite good but I wonder if something like the Whirlwind or Miles M20 canopy might be possible.

The canopy of the M.20 was probably excellent, and indeed that one at Whirly also looked the part.

Further on topic - it took me a while to find a fighter with a similar wing area and t-t-c, and the Ki-43 seems to fit the bill the best. Both have had the t-t-c at root of 18% and area of 230 sq ft. I do not how the 'NN-12' (from Nakajima) series of profiles rates vs. NACA 22XX series, though.
The Ki-43 was making ~350 mph on it's best engine ( about 950 HP at 21000+ ft), and ~330mph on the second best (about 1000 HP at 18000 ft). A Merlin should be offering a reduction of drag and easier installation of ejector exhausts than the radials in question.

Hopefully, the Gloster with Merlin should've been doing at least in-between speed figures wrt. to Hurricane and Spitfire on same (or very similar) engine power installed. 340 mph with Merlin III, 355+ mph with Merlin 45?

If/when the 'wing surgery' is attempted, I'd like to see the wing loosing a good deal of it's inner part of it. Gets rid of the thickest part of the wing + decreases wing area = lower drag = better speed.
 
I wonder if we can prise Merlin X engines out of Bomber Commands clammy hands. According to Wikipedia the X started production December 1938.
 
The cooling system on the Hurricane was not particularly inefficient, and was actually more efficient than the cooling system on the Spitfire. It is only when you start to compare it to the radiators on later designs (P-51, Mosquito, etc) that it lags behind any significant amount. The only real problem with the location of the radiator on the Hurricane was that it did not allow for center-line carriage of ordnance or DTs, but since the landing gear arrangement also prevented center-line carriage it is kind of a moot point.

I was under the impression that the Hurricane radiator was very draggy partly because of it's location.
 
The 'powerplant drag' part of the total profile drag of Hurricane II (that was worth 77 lbs of force, at speed 100 m/s) was 16%, or ~12.32 lbs; that is for the example that was tested at 330 mph at 20500 ft. On Spitfire Vb, it was 17.6% of 61 lbs = ~10.74 lbs; for an example tested at 375 mph at 20000 ft.
FWIW.

(data per AVIA 28-303 sheet)
 
The engine. It has to be a Merlin nothing else comes close unless Daimler Benz suddenly start exports.
I prefer keeping the radial engine. Swap out the Mercury with a Perseus for added power. If a FAA version is considered this will gain some skills/parts compatibility with the Skua and Albacore. Avoiding the Merlin also prevents engine delays when the Spitfire and Hurricane need/demand every unit produced.
The undercarriage. That has to go
Agreed. This will require a new wing, ideally one with wide track undercarriage and provision for folding wings.
The Tail. The rudder on the F5 was noted as very heavy I wonder if the forward position had anything to do with it.
I believe this was due to a spin recovery issue.
The redesigned F5 needs to be in service at the latest spring 1940. First flight of the F5 is according to Wikipedia December 1936 tests can take place in summer 1937 so the decision to rebuild the prototype has to happen late 1937. That gives Folland and his team 2 years to produce a Hurricane beater and 109E equivalent.
No chance. Gloster is a wholly-owned subsidiary of Hawker. Yes, we seem to forget that the Gloster Meteor was a Hawker Siddeley aircraft. There's zero chance that the stubborn and strong-willed Sidney Camm will allow his Hurricane design to be replaced with Folland's. This, I suggest is the primary reason the F5/34 was killed upon Hawker's acquisition of Gloster in 1935. And besides, in your suggested time period the entire Hawker Siddeley design team is working on finalizing the Hurricane and designing the Typhoon (first flight in Feb 1940), there's no time to be fiddling with the F5/34.

Unless Gloster can find a niche for its F5/34 that does not compete with the head office's Hurricane the F5 is dead on the vine. The best chance is to offer the F5/34 to the FAA as Hawker-Gloster's competition to the Fulmar should saner heads prevail at the AM and FAA and twin seaters are rejected. And to avoid Beaverbrook killing the project, produce the F5/34 offshore, likely in Canada, Australia or after HAL's founding in Dec 1940, (if they can do more than CKD assembly) India.

But whatever its fate, the Gloster F.5/34 was a great looking aircraft. I can just imagine it on a RN carrier.
 
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I have been following tomo pauk tomo pauk No Spitfire thread with interest and it seems to me that another British aircraft manufacturer is going to have to step up and try to build an equivalent or near equivalent to the Spitfire. It has to be British I just can't see imported or license built foreign designs being ordered or even ready to meet the Bf109 E and F.

I think the Gloster F5/34 is the most promising design. All the alternative designs come from companies that are too busy building bombers (Bristol and Vickers) too small (Miles and MB). Glosters had no projects beyond the twin engine heavy fighter which won't be missed if it's cancelled.

So starting with the F5/34 what do we need to get it up to or near 109E standard.

The engine. It has to be a Merlin nothing else comes close unless Daimler Benz suddenly start exports.

The undercarriage. That has to go what on earth was Folland doing. Maybe the Hurricane undercarriage design is used I don't think it had any problems.

The Tail. The rudder on the F5 was noted as very heavy I wonder if the forward position had anything to do with it.

The Wing. It's a one piece wing which was unusual for the time maybe design a new two piece wing.

Radiator. I believe the radiator on the Hurricane was less thanerc optimal. What is best for the radiator I would like a P51 type but that may be too early. I think it has to be Spitfire type.

The redesigned F5 needs to be in service at the latest spring 1940. First flight of the F5 is according to Wikipedia December 1936 tests can take place in summer 1937 so the decision to rebuild the prototype has to happen late 1937. That gives Folland and his team 2 years to produce a Hurricane beater and 109E equivalent.

Gloster F5/35 had Airfoil: root: NACA 2218; tip: NACA 2209
Hawker Typhoon had Airfoil: root: NACA 2219; tip: NACA 2213

So the F5/35 wasn't cursed by the thick wing of the Hawker designs. In fact that thickness chord ratio is similar to Hellcat, Corsair, Bearcat, Fw 190.

The problem is the single row Mercury IX is at 830hp/438kg is to weak for 1940 and at its development limits. The Perseus is a two row engine with less drag but the same power,

So it has to be upgraded with the two row Taurus which at 1130hp/590kg is competitive in 1939 and 1940 and maybe 1941 but perhaps not much beyond. Taurus is also only available from early 1939. After that it needs a Hercules.

Since the Taurus has 40% more power one would expect 13% more speed ie 355mph roughly.

My feeling is the F34/35 can be built and then upgraded from the Mercury to Taurus and in production benfor the war in early 1939.

A Hercules engined Gloster fighter would beat the Typhoon into production.

A heavy rudder can be fixed by a balance tab or enlarged balance horn.
 
Trouble is the Taurus engine pretty much tanked.

It gave quite a bit of trouble in the Beauforts in 1940-41 and was set up for a critical altitude/FTH of 3000ft or so. They finally got the reliability up but it stayed a low altitude engine. This was unknown in 1937-39 when a decision would have been made but building Taurus powered fighters would have resulted in a number of Squadrons flying Planes that made Hurricanes look like Spitfires.
 
It's a shame that A-W didn't design a new engine based on their Tiger, but with central bearing and other structural reinforcements. They might have kicked Bristol's arse or at least got them thinking of re-focusing on poppet valves like everyone else.

Best plan to see this plane in service? Have Hawker Siddeley sell/license the F5/34 design to someone else. The Aussies can build it before/instead of the Boomerang, with P&W R-1830 Twin Wasps, like their Beauforts. Send the technical drawings and any pre-production tooling to CAC in 1936 when it's clear the Hawker Siddeley group is focused elsewhere. Hawker needs to focus on the Hurricane and Typhoon and then get on with the Tempest and Meteor programs. There is no time nor resources in the company to pursue a concurrent 1930s fighter program.
 
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It's a shame that A-W didn't design a new engine based on their Tiger, but with central bearing and other structural reinforcements. They might have kicked Bristol's arse or at least got them thinking of re-focusing on poppet valves like everyone else.

Perhaps, but the Tiger was a bit on the small side to be a major player. 1995 cu in, The P & W R-2000 was only used in transports and on 100 octane it manage 1350hp for take-off and at 2000ft, It managed 1100hp at 13,200ft in high gear. Bristol was planning (hoping/dreaming?) to get that out of the smaller Taurus and had the 18% larger Hercules.
 
I like the idea of a better Armstrong Siddeley engine I wrote a little what if about it. However there is a problem AS manufactured the Cheetah which was a very important engine for training aircraft. If AS is busy building a better Tiger where do the 35000 plus Cheetahs come from for the Anson and Oxford.
 
The best thing is for Gloster to 1 use the Merlin or 2 have someone license produce the R-1830 or try one of the odd ball engines from Fairy. Bristol hasn't got a decent engine till the Hercules.
 
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It's a shame that A-W didn't design a new engine based on their Tiger, but with central bearing and other structural reinforcements. They might have kicked Bristol's arse or at least got them thinking of re-focusing on poppet valves like everyone else.

Best plan to see this plane in service? Have Hawker Siddeley sell/license the F5/34 design to someone else. The Aussies can build it before/instead of the Boomerang, with P&W R-1830 Twin Wasps, like their Beauforts. Send the technical drawings and any pre-production tooling to CAC in 1936 when it's clear the Hawker Siddeley group is focused elsewhere. Hawker needs to focus on the Hurricane and Typhoon and then get on with the Tempest and Meteor programs. There is no time nor resources in the company to pursue a concurrent 1930s fighter program.


The problem seems to be that Bristol is producing a dung heap of engines in the 800hp class, some single row, some two row, some poppet valve some, sleeve valve almost any permutations so long as it is around 700-800hp. They only deliver an 1100hp it will be only available in 1939 and it is at its development limit because its cobbled together from two single row radials at their development limit. Rather than developing a 1200hp engine like the R-1830 Bristol is busy inventing the sleeve valve.
 
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I like the idea of a better Armstrong Siddeley engine I wrote a little what if about it. However there is a problem AS manufactured the Cheetah which was a very important engine for training aircraft. If AS is busy building a better Tiger where do the 35000 plus Cheetahs come from for the Anson and Oxford.
Like much of the UK's aerospace industry, Armstrong Siddeley is too small, it needs to be merged into a larger operation. Had it remained part of Vickers Armstrong it AS would have had the scale to get more done.
 
The problem seems to be that Bristol is producing a dung heap of engines in the 800hp class, some single row, some two row, some poppet valve some, sleeve valve almost any permutations so long as it is around 700-800hp. They only deliver an 1100hp it will be only available in 1939 and it is at its development limit because its cobbled together from two single row radials at their development limit. Rather than developing a 1200hp engine like the R-1830 Bristol is busy inventing the sleeve valve.

What Bristol engines were around 700-800 HP in the time of interest here, and especially what 2-row radials from Bristol were at 700-800 HP?
 
Like much of the UK's aerospace industry, Armstrong Siddeley is too small, it needs to be merged into a larger operation. Had it remained part of Vickers Armstrong it AS would have had the scale to get more done.

Armstrong Siddeley was part of Hawker Siddeley which was possibly the biggest aircraft company in Britain.

I agree that British aviation companies were too many and too small dispersing engineering knowledge too thinly. I think the French idea of combining aviation companies was a good idea though France did it too late. If war had come in say 1942 I believe the French airforce would have been formidable.
 

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