Build an improved Gloster F5/34 (2 Viewers)

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An extract from my post to the Fantasy thread.

I'd like to have seen the Gloster F5/34 swap out its Bristol Mercury (Length: 47 in, Diameter: 51.5 in, Dry weight: 966 lb), skip entirely its intended Bristol Perseus (Length: 49 in, Diameter: 55.3 in, Dry weight: 1,025 lb) and instead use a Pratt & Whitney R-1830 Twin Wasp (Length: 59.06 in, Diameter: 48.03 in, Dry weight: 1,250 lb). The 10 in. longer and significantly heavier engine will necessitate changes to the CoG. While we're at it, we'll replace the undercarriage and make a smooth lower wing surface.

Can we make this work?
Sure, if you want to use the R-1830 that made about 950hp for take-off and max continuous of 830hp at a whopping 3600ft.

https://www.enginehistory.org/Piston/P&W/R-1830/R-1830Index.pdf

If you are looking for R-1830 engines that made 1100-1200hp for take off you need one of the ones that went over 1400lbs and you probably need a heavier propeller.
Lets remember that the Curtiss 75 started at about 4800lbs and wound up at around 5600lbs with the early R-1830s used the P-36. And they had problems with the wings and landing gear that needed beefing up.

Maybe you can get it to work, but it needs a lot of changes. Don't forget to increase the size of the fuel tanks to feed the bigger engine.
I wonder if a Wright R-1820 would be a better choice?
Length and diameter are farily similar (GR-1820-G2, as the given example @ Wikipedia), but weight (once again) quickly goes past 1000 lbs., once we get around 1000 HP....and at that point, it would probably make more sense to go with the Pegasus engine, instead....oh well, it was an idea.
 
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It's easy, with our contrarian tendencies to focus on exclaiming why something would not, could not or should not have occurred. The trick is considering how to reasonably overcome these challenges. Focus on the how, not the why not.
OK, let us assume that some British company (Tommy's tin whistles, LTD) signs a deal with P & W. Now the question to be answered are WHEN. As in which version of the R-1830 because it was undergoing constant development.
The First commercial plane to be certified with the R-1830 was the Marin Clipper on Oct 9th, 1935. Engine maxed out at 2550rpm for take-off at 950hp. Supercharger was pure crap.
At 2400rpm max continuous was 830hp at 3600ft.
The 2nd commercial plane to be certified with the R-1830 was the DC-3A on Nov 28th, 1936. This version of the engine could run at 2600rpm for take-off and 2450rpm max continuous. Supercharger was still crap but a higher supercharger gear allowed for 900hp at 6000ft. Engine gained 75lbs.
The C series engines show up a bit later and they will run at 2700rpm, a larger supercharger offers 900hp at 11,000ft (supercharger has larger impeller and turns slower than the old supercharger). Engine has gained 113lbs. For TTW, Ltd, all of these engines will run on 87 octane fuel, which might be important in 1937-38. These are the engines the French bought for their first Curtiss Hawks and for their own Bloch fighters. The 1200hp engines used in the Australian Beauforts don't show up until later.
Saying somebody could have made a different decision is one thing, asking for a time machine is something else.
Also important as the why we can consider Alvis. A competitor to TTW, Ltd, Alvis signed a deal for the range of G-R engines in 1938 and started looking for business from the Air Ministry. Rightly or wrongly the Air Ministry did not to deal with another engine company. Alvis, not being completely stupid, only built a small factory (large shop) capable of truing out 15,000hp worth (?) engines a week as announced in the aviation press of the time. Now if they are making only 14K or Ns that is under 15 engines a week at max capacity. They never got any orders and did a lot of overhaul work and subcontracting. They also greatly expanded the facilities.
Getting back the when. The later model R-1830s used very few parts in common with the early engines.
The Australians put "foreign made engines" into their Bristol Beauforts.
They used both and Australia was not happy with the way the British treated them both before and during WW II.
It also took several years for the Australians to make R-1830s in Australia. It was not a matter of political will. It was also a matter of getting the needed machine tools and equipment and training a work force.
This is something many politicians refuse to acknowledge. You can't build and equip factories in just a few months and you also cannot come up with a skilled workforce in just a few months. You can, at times reduce a work force and keep a cadre of workers to help ramp things up if needed but it is very hard to start from zero.
 
Had that made it to production AND the PTO, I could see a lot of blue on blue incidents.
Indeed. Some bright Aussie paintwork will be needed, like the dazzle scheme used on this Buffalo

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...Or in modern day at Qantas.

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Or go RAAF anniversary blue (skip the red strips) and swap out the roundels for 'roos.

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I wonder if a Wright R-1820 would be a better choice?
....probably make more sense to go with the Pegasus engine
If we're giving the Gloster to CAC the Australians will never want a Bristol engine. And with the 1940-start of P&W Twin Wasp production in Australia, the Wright R-1820 Cyclone is out. I'd like to see a performance comparison between Twin Wasp and Bristol-powered Beauforts.

I think this is the best chance of getting the Gloster F5 into service. We've removed it from the British Air Ministry's oversight, taken over the rights, drawings and any tooling from Gloster's new owners at Hawker Aircraft and thus removed any internal company competition with the Hurricane, and replaced its imported Bristol engine with a domestically produced engine of superior power and reliability.

The challenge is how do we install a longer and heavier Twin Wasp into this airframe, shown below with a Bristol Mercury.

gloster534-6.jpg


Perhaps we can move the wing spar and cockpit backwards. Or stick a lump of weight in that fat tail. I like the incline from the windscreen to the nose for visibility, which should be keepable with the P&W diameter. It would be handy to see a cutaway of the Gloster, as perhaps there's empty space behind the engine like on the Skua.

Here's a P&W Twin Wasp. Fourteen cylinders. 30L, 59 in length, 48 in diameter, 1,250 lb (dry), 1,200 hp. And here's what we're trying to replace. The Bristol Perseus. Nine cylinders. 25L, 49 in length, 55 in diameter, 1,025 lb (dry), 905 hp. Doesn't that American engine look space-age by comparsion?

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Perhaps we can move the wing spar and cockpit backwards. Or stick a lump of weight in that fat tail.
Perhaps move the vertical stab rearward, and add a retract mechanism for the tail wheel. That would go part of the way in shifting the CofG into acceptable territory, but much more would be required.
 
Perhaps, having lost interest upon their acquisition of Gloster in 1935, Hawker Siddeley Group trades the F5/34 project to Commonwealth Aircraft Corporation (CAC) in Australia, where it becomes a RAAF fighter in 1941.
Perhaps have it presented to Lawrence Wackett's overseas evaluation mission to inspect aircraft production.
 

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