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If the sleeve valves failed, would this engine have done better if it had the same resources thrown at it as the Vulture?
You can fix just about anything if you throw enough money and time at it. The question is should you?
When your research and development (resources) starts doing things like getting the intake manifolds/passages out of the crankcase, modifying the valves and cylinder heads, beefing up crankshafts and other parts you might wonder wither you should have started with something else to begin with.
Take another look at it, it is not a fighter engine, it is a bomber (big bomber) or perhaps maritime patrol plane engine, being able to shut 1/2 the engine and cruise on the other half? However this also means you need twice the instruments, twice the controls, separate oil and coolant systems and so on. Perhaps the engine could have been simplified but it was too dated.
Old Machine press has quite a write-up on it and a good look at some of the patent drawings will show some of the problems. If people think the Allison had poor intake manifolds this thing was a horror. At least you could replace the allison manifolds without replacing the crankcase.
Given the scenario presented of "no-sleeve-valve-engines" does the Fairey product become worthy of further development? Does the ministry hand it off to Napier or Bristol in say 1938? (Or even earlier)
As far as the instrumentation? Dual pointer instruments were available at the time and do not pose a insurmountable issue. Weight wise, the engine appears to be about the same as a Sabre. Dimensionally, I'd bet they're close...(With the deck height advantage going to the Sabre.) As far as heat rejection? again, probably about the same as a Sabre or a Griffon. (How many radiators under the wing or in the root of a Spitfire or Tempest?)
In fact, I'll say for the fun of it that redundant systems if they could be packaged in an envelope similar to that of the Griffon or the Sabre would enhance combat survivabilty.
The Fairey P.24 Civil Type Test [50h] was undertaken between 13 May 1939 and 14 June 1939.
The rated output was 1205hp @ 10,500ft at 2400rpm.
The maximum output was 1450hp @ 10,500ft, maximum speed 2750rpm.
Bore: 5.254" (133.5mm)
Stroke: 6.00" (152.3mm) [from the report, should be 152.4mm if it is 6"]
Capacity 3124.3ci (51.2l)
BMEP at rated hp at "International RPM" was 127psi.
The carburetors were fitted with automatic boost controls.
Nett dry weight was 2202lb, gross dry weight (not including propeller hubs or engine mounting) was 2329lbs.
Also, there have been a few threads about the Fairey P.24 over the years.
Fairey aero engines - any good info?
If I may quote myself:
Speaking of hp per sq/ft, this is a bit off subject, but I saw at the National Air Force Museum a strange engine but I could never find much about it. It primarily operated off a slanted plate on the drive shaft, I'm sure there is a name for it, which operated on pistons operating parallel to and around the drive shaft ala 1960s GM air conditioner compressor. It certainly operated on a reduce frontal area. It must have had serious problems as I never read anything about it. Let me know if you are anyone else has any information on this particular engine implementation.Designers were a lot more obsessed with hp per sq/ft of frontal area at the time which influenced cylinder arrangements.
I wonder what the numbers would have looked like if the Fairey engine tried to pass an American type test?I wonder what the numbers would look like if the R2800 was run on the same fuel as the Fairey engine? And if the Fairey engine had 50% of the resources thrown at the Sabre or the Vulture. (Remember, we're what if here.)
How much this change the 'scene', predominatly at Bristol and Napier? Gains vs. losses? Possible effects on ww2 design and production of both engines and related aircraft?
Start making Merlins and Griffons under license.
Halifax, Beaufighter, Wellington with Merlins, up to its 2,000 hp versions.
Typhoon/Tempest with Griffon (the latter with a 2 -stage version).
Bristol would just make poppet valve radials
I wonder what the numbers would have looked like if the Fairey engine tried to pass an American type test?
and P & W worked up some figures for the R-2800 running on 90 octane fuel even if they didn't actually build such engines (maybe to find out what the engine could do if they couldn't get 100 octane?) in any case 1625hp/2600rpm at sea level for take-off. 1625hp/2600rpm at 6500ft and 1250hp/2600rpm at 16,800ft in low and high gear military power and 1450hp/2400rpm at 8500ft and 1200hp/2400rpm at 16,000ft max continuous.
Something wrong with the Fairey's superchargers?
Resources can help but they can't change the laws of physics. You design a convoluted intake duct with lots of sharp turns and no amount of resources is going to be able "fix" it.
You need to throw it out and start over. The siamesed intake ports and two of the four exhaust ports are siamesed, Ok on low powered engines, not so good on high powered ones,
Development and resources often meant an increase in weight. Three countries tried to "improve" the Hispano V-12. ALL three succeeded by around 1947-48. All three got 30-40% more power than the pre war engines got. ALL three gained several hundred pounds, including much heavier crankshafts. All three resorted to new cylinder heads. At least two used fuel injection. All used new or different superchargers. All three failed to catch the Merlin.
There must be something inherently flawed about the design to just disappear. It seems to offer significant benefits to aircraft designers such as burying the engine in the wings of bombers significantly reducing not only area drag but also interference. And, How much more space would be available in a P-39 for a turbo-supercharger, and so on. Tis a puzzlement.Swashplate engines were one of the more-or-less dead ends of combustion engine technology. Interestingly, they are used for some very successful hydraulic pumps and motors.
Not really.
The main problem is the limited number of cylinders. If you can only get 80-100hp per cylinder on a given type of fuel and you are happy with a 300-600 hp engine (4 to 6 cylinders) then they may provide an alternative form of engine. If you are looking for a 1200hp engine and you arrange 12 cylinders in a circle like a big revolver cylinder then the bulk and weight may or may not be competitive with either a V-12 or a two row 14 cylinder radial. Want more than 1200hp? P&W R-2800 was making 111hp per cylinder at 2000hp. 18 cylinder swashplate engine
Not really.
The main problem is the limited number of cylinders. If you can only get 80-100hp per cylinder on a given type of fuel and you are happy with a 300-600 hp engine (4 to 6 cylinders) then they may provide an alternative form of engine. If you are looking for a 1200hp engine and you arrange 12 cylinders in a circle like a big revolver cylinder then the bulk and weight may or may not be competitive with either a V-12 or a two row 14 cylinder radial. Want more than 1200hp? P&W R-2800 was making 111hp per cylinder at 2000hp. 18 cylinder swashplate engine
Not really.
The main problem is the limited number of cylinders. If you can only get 80-100hp per cylinder on a given type of fuel and you are happy with a 300-600 hp engine (4 to 6 cylinders) then they may provide an alternative form of engine. If you are looking for a 1200hp engine and you arrange 12 cylinders in a circle like a big revolver cylinder then the bulk and weight may or may not be competitive with either a V-12 or a two row 14 cylinder radial. Want more than 1200hp? P&W R-2800 was making 111hp per cylinder at 2000hp. 18 cylinder swashplate engine