Build an improved Gloster F5/34

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Armstrong Siddeley was part of Hawker Siddeley which was possibly the biggest aircraft company in Britain.
Yes, but only in 1935, by which time it was too late to create a competitor to Bristol sleeve valve radials. Throughout the interwar period what was to become AS was first stuck in a failing Armstrong Whitworth conglomerate, and then broken off into a relatively small private firm by John Siddeley, with primary focus on automobiles rather than aircraft.

The History of Armstrong Siddeley and its Associated Companies

Their pre-war cars were attractive.

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Just so we are all on the same page (or at least the same chapter.

Pollitt-1940_Gloster_F5-34 resize.jpg


This is from C.A.H. Pollitt's 1940 book "Scale Plans of Military Aircraft"

They seem to have taken lessons from Seversky in fuselage design.

With a 51.5in diameter engine they managed a 60in (roughly ) diameter in the cockpit area? Roomy for long range flights?

Great vision from the cockpit for combat or landing but that rise from cowl in drawing is not far off.
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In 1938-39 unless you stick a Merlin in it none of the possible choices are very good.

The Mercury IX weighs 1010lbs (51.5in dia) or so and gives 840hp at 14,000ft and 725 hp for take-off.
The Perseus X sleeve valve weighs about 1100lbs (52.0 in dia) and gives 880hp at 15,500ft and 750hp for take-off.
The two speed Pegasus weighs about 1135lbs (53.3in dia) and gives 885hp at 15,500ft and 965 hp for take-off.
Taurus seems a bit of crap shoot.
The MK II is about 1300lbs ( 46.2in dia) and gives 1110hp at 4000ft and 1060hp for take off at 3100rpm.
The MK III is about 1300lbs ( 46.2in dia) and gives 1060hp at 14,5000ft and 935hp for take off at 3300rpm.

No Taurus after the MK III is listed at running faster than 3100rpm. And no production Taurus is listed as using more than 4.75lbs of boost regardless of fuel.

Hercules
The early ones start at about 1835lbs (52in dia) and the MK III (first two speed engine) gives about 1210hp at 15,000ft in high gear.

None of the Bristol engines offer much in the way of exhaust thrust.

Only British radial left is the Tiger and a discrete curtain will be pulled across that one.

French engine/s are pretty much limited to the G-R K series, the Ns don't show up in time.
For the American engines it is pretty much the R-1820 G 100 of about 1000-1100hp for take off (engines used in the Buffalo) or
the P & W R-1830 but in 1938-39 they are single speed supercharger engines and around 1000-1050hp is about max power.
 
In 1938-39 unless you stick a Merlin in it none of the possible choices are very good.
Hawker Siddeley already has an eight gun single seat Merlin fighter; no chance Camm puts another forward. We might as well expect Vickers to put Merlins onto their Venom instead of allocating them to Spitfires.

We need the F5/34 to present Hawker with an opportunity to meet different markets than the Hurricane. If the F5/34 is just duplicating and dispersing Hawker's investment and time, it has to die. That needs to be the point of this thread, we need to first find a niche for the F5/34 and then modify the aircraft accordingly. That niche needs to be either the FAA, colonial/dominion RAF/RAAF/RNZAF/RIAF/SAAF service or export sales, perhaps produced outside the UK.

If competitively-engined and improved as listed in the posts above, the F5/34 would be a good alternative to the CW-21, P-26, P-36, P-43 and P-66 used by the Chinese and/or DEI, for example. But the engine is the issue, we must toss Bristol for a P&W or CW power plant.
 
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Just so we are all on the same page (or at least the same chapter.

View attachment 617418

This is from C.A.H. Pollitt's 1940 book "Scale Plans of Military Aircraft"

They seem to have taken lessons from Seversky in fuselage design.

With a 51.5in diameter engine they managed a 60in (roughly ) diameter in the cockpit area? Roomy for long range flights?

Great vision from the cockpit for combat or landing but that rise from cowl in drawing is not far off.
View attachment 617428

In 1938-39 unless you stick a Merlin in it none of the possible choices are very good.

The Mercury IX weighs 1010lbs (51.5in dia) or so and gives 840hp at 14,000ft and 725 hp for take-off.
The Perseus X sleeve valve weighs about 1100lbs (52.0 in dia) and gives 880hp at 15,500ft and 750hp for take-off.
The two speed Pegasus weighs about 1135lbs (53.3in dia) and gives 885hp at 15,500ft and 965 hp for take-off.
Taurus seems a bit of crap shoot.
The MK II is about 1300lbs ( 46.2in dia) and gives 1110hp at 4000ft and 1060hp for take off at 3100rpm.
The MK III is about 1300lbs ( 46.2in dia) and gives 1060hp at 14,5000ft and 935hp for take off at 3300rpm.

No Taurus after the MK III is listed at running faster than 3100rpm. And no production Taurus is listed as using more than 4.75lbs of boost regardless of fuel.

Hercules
The early ones start at about 1835lbs (52in dia) and the MK III (first two speed engine) gives about 1210hp at 15,000ft in high gear.

None of the Bristol engines offer much in the way of exhaust thrust.

Only British radial left is the Tiger and a discrete curtain will be pulled across that one.

French engine/s are pretty much limited to the G-R K series, the Ns don't show up in time.
For the American engines it is pretty much the R-1820 G 100 of about 1000-1100hp for take off (engines used in the Buffalo) or
the P & W R-1830 but in 1938-39 they are single speed supercharger engines and around 1000-1050hp is about max power.

The drawing is not to scale it looks like someone drew it without any access to the actual aircraft or photos.

I said in my first post it has to be the Merlin engine. No other engine apart from the DB601 can provide the power in the size required.

This isn't an exercise in building an export fighter or a Hurricane replacement or a naval aircraft this is to replace the Spitfire that either never got an order or was never built because Supermarine were too busy building bombers and flying boats.

I want a Gloster fighter able to meet a Bf109E on roughly the same terms as the Spitfire MkI.
 
I want a Gloster fighter able to meet a Bf109E on roughly the same terms as the Spitfire MkI.

Well, you aren't going to get such a fighter out of the Gloster F5/34.

Drawing may very well not be true to scale.
Series of pictures here.
Gloster F.5 / 34 - Destination's Journey


Unfortunately some of the good features, like the excellent view from the cockpit, come with a cost, high drag. Please see the MC 200 or the F4F or F6F.

To get a Spitfire equivalent out of the Gloster you need a new wing, new landing gear, a new fuselage/cockpit and a modified rudder/vertical stabilizer.
All in addition to sticking the V-12 engine in the plane. Seems like you get to keep the horizontal stabilizer and the canopy ;)

I can't seem to figure out why the Bristol 146 was just about 30mph slower than the Gloster using the same engine?
Bristol-146-2.jpg

unless that canopy was doubling as an airbrake?
 
You will certainly got such a fighter if the Gloster is outfitted with Merlin III. Just like what the Re.2000 gotten when it became Re.2001, despite legacy of fuselage tailored erstwhile for a radial, the 'humpback' cockpit, and U/C not being example of streamlining.
 
Hawker Siddeley already has an eight gun single seat Merlin fighter; no chance Camm puts another forward. We might as well expect Vickers to put Merlins onto their Venom instead of allocating them to Spitfires.

We need the F5/34 to present Hawker with an opportunity to meet different markets than the Hurricane. If the F5/34 is just duplicating and dispersing Hawker's investment and time, it has to die. That needs to be the point of this thread, we need to first find a niche for the F5/34 and then modify the aircraft accordingly. That niche needs to be either the FAA, colonial/dominion RAF/RAAF/RNZAF/RIAF/SAAF service or export sales, perhaps produced outside the UK.

If competitively-engine and improved as listed in the posts above, the F5/34 would be a good alternative to the CW-21, P-26, P-36, P-43 and P-66 used by the Chinese and/or DEI, for example. But the engine is the issue, we must toss Bristol for a P&W or CW power plant.

The situation initially seems hopeless without a better engine. Even the R-1830 seemed limited. The Curtiss P-36, Seversky P-35, Republic P-43 (needed a turbo chargers but had good performance) and Vultee P-66 (had good performance, 340 mph), Brewster Buffalo are lacklustre.

The Taurus (which is becoming available only in 1939 and with teething problems) might do the job along with two speed R-1830 but it would require care in airframe design.

The two fighters that showed what radials could do were the A6M Zero (960hp Sakae engine) which entered service June 1940 only 2 month before the Me 109F1 August 1940 and the Fw 190A in August 1941.

So while using a R-1830 or Taurus could make a competitive airframe it would have to use a superbly well constructed airframe. Something like the Zero but it could afford some armour.

Basically Gloster has to try again just like supermarine tried again, perhaps using a R-1830 as an interim engine until the British Bristol Taurus is available.

To be noted is just how good the Me 109E and Me 109F were for their era with only the Spitfire a serious competitor.

One of the Me 109X-0 prototypes was powered by a 1,200-hp Pratt & Whitney 'Twin Wasp' R-1830 SC-G. It would be interesting to know its top speed.
 
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Well, you aren't going to get such a fighter out of the Gloster F5/34.

Drawing may very well not be true to scale.
Series of pictures here.
Gloster F.5 / 34 - Destination's Journey


Unfortunately some of the good features, like the excellent view from the cockpit, come with a cost, high drag. Please see the MC 200 or the F4F or F6F.

To get a Spitfire equivalent out of the Gloster you need a new wing, new landing gear, a new fuselage/cockpit and a modified rudder/vertical stabilizer.
All in addition to sticking the V-12 engine in the plane. Seems like you get to keep the horizontal stabilizer and the canopy ;)

I can't seem to figure out why the Bristol 146 was just about 30mph slower than the Gloster using the same engine?
View attachment 617442
unless that canopy was doubling as an airbrake?

It think they simply over did the canopy and combined it with an overly cut down rear tail. The latter being the real problem I feel.
EC66FCF7-2396-46A5-B803-6ACE8E8C931D.gif


BB4E2F04-EBCB-428D-A709-741057AB2FCC.jpeg
 
I want a Gloster fighter able to meet a Bf109E
Here's the best way to that, if you can wait until 1941. 23 Feb 1940, the day before it flies, stick a Gloster emblem onto the company's Typhoon. Clearly if Camm was willing to call his first jet fighter a Gloster, he's not that determined to call everything a Hawker.

Here's three of Hawker's best aircraft. I'm not sure how we can get the F5/34 into this level of company. Maybe the Sabre engine is rejected along with the X-engines, and the Centaurus is late, meaning the Typhoon/Tornado project is dropped and a rush for a Hercules engined fighter is made? Someone pulls the dust cover off the F5/34 prototype and says, well we do have this as a starting point.

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You will certainly got such a fighter if the Gloster is outfitted with Merlin III. Just like what the Re.2000 gotten when it became Re.2001, despite legacy of fuselage tailored erstwhile for a radial, the 'humpback' cockpit, and U/C not being example of streamlining.
This is like sticking an Allison in a P-35 and still expecting to get a P-40. Let's also remember that the XP-40 didn't go over 300mph until they redid the radiator and fitted ejector exhausts.
 
This is like sticking an Allison in a P-35 and still expecting to get a P-40. Let's also remember that the XP-40 didn't go over 300mph until they redid the radiator and fitted ejector exhausts.

Ejector exhausts were a thing just before ww2. As for the radiator - I've suggested the same radiator as on the P-40 for the Gloster.
The lowest top speed for the initial XP-40 (one with bad exhausts and aft radiator) during October of 1938 is quoted at 326 mph at pg. 94 of 'Vee's for victory'.
We also have a thing of Merlin II/III being a better engine than V-1710 of 1938-39.
 
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Here's the best way to that, if you can wait until 1941. 23 Feb 1940, the day before it flies, stick a Gloster emblem onto the company's Typhoon. Clearly if Camm was willing to call his first jet fighter a Gloster, he's not that determined to call everything a Hawker.

Here's three of Hawker's best aircraft. I'm not sure how we can get the F5/34 into this level of company. Maybe the Sabre engine is rejected along with the X-engines, and the Centaurus is late, meaning the Typhoon/Tornado project is dropped and a rush for a Hercules engined fighter is made? Someone pulls the dust cover off the F5/34 prototype and says, well we do have this as a starting point.

View attachment 617461

Camm was an employee not the boss even at Hawkers. Hawker Siddeley had shareholders and directors and Camm telling them what to do would be like the Chief engineer of a battleship telling the Admiral of the fleet how to fight the battle.

Camm didn't have much if anything to do with the Meteor that was George Carter's baby. Hawkers and Gloster were separate companies owned by Hawker Siddeley and the Hawker design team had its hands full trying to turn the Typhoon into a useable aircraft. Hawkers didn't get into the jet business till late 44 when a proposal to build a jet version of the Griffon engined Fury was put forward. By this time Gloster was building its third jet plane and thinking about the design that became the Javelin.

Ultimately the only organisation that decided who built what and where was the customer the government. If the government wanted Hawkers to build barrage balloons that's what they would build.

The improved Gloster F5 is to replace the Spitfire that in this timeline doesn't exist for reasons. The RAF wants a 360mph + fighter and the F5 was the best of the designs. My thinking is an average radial engine fighter has its weedy radial replaced with the best available V12.

Hint...Macchi 200 to 202 and then 205.
 
Macchi started to work on the MC202 late 1939 when a license to build the DB601 was obtained. The 202 came into service in November 1941 in Libya. 2 years to take an established design and re-engineer it to give a 370mph + fighter. If Mario Castoldi could do it whilst hampered by a comparatively less well developed aviation industry then I am sure Henry Folland backed by the British aviation industry could do the same a year or more earlier.
 
Macchi started to work on the MC202 late 1939 when a license to build the DB601 was obtained. The 202 came into service in November 1941 in Libya. 2 years to take an established design and re-engineer it to give a 370mph + fighter. If Mario Castoldi could do it whilst hampered by a comparatively less well developed aviation industry then I am sure Henry Folland backed by the British aviation industry could do the same a year or more earlier.
Now the Italians, they were the guys to ask for an attractive A6M-lookalike fighter, with a coincidentally similar designation.

Caproni Vizzola F.5

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Just like what the Re.2000 gotten when it became Re.2001,

Hmmm, The Re.2000 was supposed to do 329mph at 16,400ft with a 986hp Piaggio XI engine.
The Re.2001 was supposed to do 337mph at 16,400 with the 1175hp Alfa Romeo built DB 601. It did have under wing gun pods for more drag. It also gained about 1000lbs of empty weight. Somehow I see this as a Hurricane equal and not a Spitfire equal.

.Macchi 200 to 202
Something of the same as above. Macchi did a somewhat better job of converting but also made a larger jump in power. 870 hp to 1175.
The Gloster will go from 840hp to 1030hp if built before 1940.
The MC 200 was supposed to go 312mph at 14,750ft. Yes the MC 202 did 370mph at 16,400ft. and did it with a a 7.7mm gun inside each wing. The MC 202 did get a pair of 8.8imp gal fuel tanks in the wings to help feed the bigger engine. The MC 202 also gained about 1000lbs of weight while empty (and more loaded) Part of the MC 202s secret to high speed was that it was a small airplane, 180 sq ft. wing (78% the size of the Bristol's wing)

The Gloster does seem to rather light for it's size.


Basically Gloster has to try again just like supermarine tried again, using a R-1830 as an interim engine until the Bristol Taurus is available.

The Taurus was never available as a fighter engine and was highly unlikely to ever be available without a thorough redesign. It was usable as a torpedo bomber engine because they set up the supercharger for peak power at 4000ft. They derated it by 200rpm. It was never rated to use more than 4.75lbs boost even with 100/130 fuel.

You are much better off sticking with the R-1830 engine.
 
Hmmm, The Re.2000 was supposed to do 329mph at 16,400ft with a 986hp Piaggio XI engine.
The Re.2001 was supposed to do 337mph at 16,400 with the 1175hp Alfa Romeo built DB 601. It did have under wing gun pods for more drag. It also gained about 1000lbs of empty weight. Somehow I see this as a Hurricane equal and not a Spitfire equal.

The wing guns were installed within the wing of Re.2001, not in the pods.
Alfa-Romeo built DB 601 was still a DB 601, the take-off power that might go to 1175 HP will not be available at rated altitude. Italians give 1050 HP at 4500m for both A-R and German-made engines. Difference in engine power above 4500 m was under 10%, Piaggio IX vs. DB 601A. For Mercury vs. Merlin, the later offered more than 35% better power above 16000 ft, with less drag and better exhaust thrust (same advantage with what Re.2001 had vs. Re.2000).
Italians also give 518 km/h (322 mph) for the Re.2000, and 543 km/h (indeed 337 mp/h) for the Re.2001 in this contemporary document. This is equivalent of Hurricane II performance, with engine power no better than what Hurricane I had.

In a scenario where Gloster makes their fighter with Merlin III on board from 1938 or at least from early 1939, Spitfire might end up with Merlin XX in the nose in time of BoB and later, since there is no dire need to up-engine the Hurricane with the Merlin XX. For 1941-43, it can receive the Merlin 45 etc. to remain relevant.

Something of the same as above. Macchi did a somewhat better job of converting but also made a larger jump in power. 870 hp to 1175.
The Gloster will go from 840hp to 1030hp if built before 1940.
The MC 200 was supposed to go 312mph at 14,750ft. Yes the MC 202 did 370mph at 16,400ft. and did it with a a 7.7mm gun inside each wing. The MC 202 did get a pair of 8.8imp gal fuel tanks in the wings to help feed the bigger engine. The MC 202 also gained about 1000lbs of weight while empty (and more loaded) Part of the MC 202s secret to high speed was that it was a small airplane, 180 sq ft. wing (78% the size of the Bristol's wing)

The Gloster does seem to rather light for it's size.

As above - best-case figure for the DB 601A seems to be 1050 HP at 4500m (a figure better than what Germans give), unless spun at 2600 rpm. But indeed, the power 'spike' was major, similar to what Merlin III was offering vs. Mercury.
The MC 202 also gained the closed cockpit, it matters once speeds get high. Indeed, it was a small aircraft, reasonably stremlined, with half-burried radiator (no boundary-layer splitter, though), and wheel well covers. Not much of gun ports and chutes to mess with airflow.
It was certainly a small fighter when compared from US or UK point of view, a benefit wrt. to drag and speed.
 
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