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I'm not concerned with dead end design specs that had to changed and were never used.Challenge is the F5/34 was never intended to run the Mercury, but instead the more powerful, but then unavailable Perseus. How does the Junior compare in hp, etc
The article has its good and bad guys with too many adjectives for my tastes. Predicting the future is a great way to look foolish but predicting the past is easy.
Perseus was also of the greater diameter, 55.3in vs. 51.5in for the Mercury. Add the 100 extra lbs for the engine weight, and all and any supposed gain of performance - both speed and RoC - is cancelled.OK, lets compare the two engines
Engine........................................Mercury VIII......................Perseus X
take-off power...........................725hp....................................750hp
Power at alt..............................840/14,000............................880/15,500
Weight............................................1010lbs.................................1110lbs
Anybody see a big increase in performance here? A whopping 5% power at altitude?
Early Perseus engines used the same S/C as the high-altitude Mk.X (that, as far as actual use, went nowhere), but with lower drive ratio. The Mk.Xa used the cropped S/C but with the higher drive ratio (see here).There were higher powered Perseus engines but just about all of them used a modified supercharger for lower altitude work.
Getting 905-930hp(?) at 6,000-6500ft and another 80-140hp for take-off, while good for torpedo bombers, gives you a real clipped wing chicken (crippled flight) for a fighter instead of a Hawk.
This does rather enforce my view that one needs to look for less aeroplane behind the engines one could get than hoping to find more powerful engines to put on the front of the airframe. To me the obvious is the Vickers Venom. The Mercury is less than 9cm wider than an Aquila, albeit noticeably heavier. The Pratt & Whitney Twin Wasp Junior is even narrower than an Aquila.Perseus was also of the greater diameter, 55.3in vs. 51.5in for the Mercury. Add the 100 extra lbs for the engine weight, and all and any supposed gain of performance - both speed and RoC - is cancelled.
Early Perseus engines used the same S/C as the high-altitude Mk.X (that, as far as actual use, went nowhere), but with lower drive ratio. The Mk.Xa used the cropped S/C but with the higher drive ratio (see here).
The end result was similar, all the in-service marks being 'set' for the low-altitude power, but hopeless above 10000 ft. In taking advantage of the 100 oct fuel, Mercury was far better.
They built about 7(?) Aquila engines total, I don't think more than 2 had the same specification/standard of build. And they didn't work all that well. Combine that with the zoo show of the entire sleeve valve manufacturing in 1939/early 1940 and the chances of getting anything usable out of the Venom is about zero.This does rather enforce my view that one needs to look for less aeroplane behind the engines one could get than hoping to find more powerful engines to put on the front of the airframe. To me the obvious is the Vickers Venom. The Mercury is less than 9cm wider than an Aquila, albeit noticeably heavier. The Pratt & Whitney Twin Wasp Junior is even narrower than an Aquila.
The Venom was made for the same requirement F5/34 as the Gloster and seems to have done as well if not better on far less power. Not just popping a Mercury or Twin Wasp Junior on the front of course. The extra weight or diameter will need some reworking of the fuselage. The Aquila is, crudely, half a Taurus (or rather the other way round) and indeed is not going anywhere useful but the airframe was excellent so the suggested possible greater alternatives will enhance the performance. Not to mention the small span and excellent deck landing quality estimation may tempt the Royal Navy for the Nimrod replacement too. Vickers and Supermarine are too busy to make it but Glosters have the OTL Gladiator capacity which might be spared and Bouton Paul the Roc production line. The US Navy used single seat Spitfires to spot for naval shore bombardment so just perhaps the Venom could cover the Lysander's tasks with 2x250lb bombs too and do so more survivably. It would be easier to make an improved Venom than an improved Gloster which needs proper retractable wheels and more power which can, in period, only come at the expense of OTL Merlin engined types.They built about 7(?) Aquila engines total, I don't think more than 2 had the same specification/standard of build. And they didn't work all that well. Combine that with the zoo show of the entire sleeve valve manufacturing in 1939/early 1940 and the chances of getting anything usable out of the Venom is about zero.
The Twins Wasp Junior was skinny. Most went around 1100lbs so power to weight was not good. Aside the The US navy the main customer were the French (they loved small 14 cylinder radial engines) and the British inherited a bunch of French contracts and a bunch were stuck in Miles Master trainers and few other odds and sods.
Most the later engines were good for 825hp at take-off and 825hp at 7200ft military power.
Now perhaps you can put less airplane behind the engine but if you want eight .303s, decent fuel, armor seat back, BP glass and even horse hair and glue on the fuel tanks you need more airplane than most of the 1936-39 planes offered without loosing a lot of performance.
a 15.6 liter engine or about 71% of the size of the engine in an AT-6, Harvard or Wirraway. Granted it turns at higher rpm but the sleeve valve cool aid was a strong batch for this one.The Aquila is, crudely........
I suggested the 1535 because it was a 14 cylinder engine that was closer to the size and weight of the Mercury IX engine that ended up in the F.5 than the 1830, which was being suggested as a replacement for the Mercury, in the hands of the Aussie's.It was nearly an orphan. By the far the largest customer was the US Navy who were entranced by the small diameter and view over the nose. P & W in the late 30s realized they were fooling around with too many engines at the same time and they axed the R-1535 from R & D while completing existing contracts.
We are getting into the time warp again. Aussies are familiar with P & W R-1340 Wasp several years before they try making the Twin Wasp. Please note the names are not strictly accurate. The Twin Wasp actually uses slightly smaller cylinders than the Wasp. The R-2800 Double Wasp uses the same diameter cylinders as the Wasp but a bit longer stoke. Cylinders and cylinder heads are not interchangeable.
And that is why P & W gave up on it. They had a 600 hp Wasp, they had a 1000-1200hp Twin Wasp. The market for a 900-1000hp Twin Wasp Junior was small. P&W also abandoned the R-2180 Twin Hornet at about the same time. P&W was also still selling a trickle of R-1690 9 cylinder Hornets for customers that wanted an 875hp engine that was fatter but cheaper. Some went into Lockheed 14s and 18s.
They gave up on the R-2180 because it did use the same cylinders as the R-2800 and it was just about the same diameter so you could get about 28% more power for the same frontal area. They wanted to beat the Wright R-2600 and not trail behind it.
And in 1934-35 the engine was 600-700hp Jumo 210 91.7 liters. The DB 601 was not fitted until 1938.I like the idea of downsizing the plane when you don't have a more powerful engine.
About the same as the Bf 109. The smallest airframe for the most powerful engine you have.
And I believe the "fury monoplane" was supposed to use the RR Kestrel engine which was 21.2 liters.If we look at it that way, the Gloster F5/34 is much too big. We need an analogy to Hawker's study before the Hurricane. That study resulted in, practically, a Fury monoplane (a biplane Fury, not the one from '44).
P-40 was behind the curve already by mid-1941? Certainly by mid-1942.I cannot imagine the Gloster F5/34 by any stretch of the imagination as a fighter that would roam the skies of Germany in 1944.
Of those designs around 1935, only the Spitfire and the Me 109 (each for their own reasons) were in the front lines in 1945. The Hurricane faltered already in 1941, the P-36 as well, if we count the P-40 then in 1944?
Agreed.So the only niche where I can imagine Gloster's radial fighter (because of the Hercules Centaurus story and the Hawker/Merlin factor) is as, well, in fact, the monoplane Gladiator. And right in that timeframe instead biplane Gladiator.
If we split the P-40 into airframe and engine then the P-40 airframe was still on the curve in 1941-42-43. It may not have been on the leading edge but anything that wasn't P-51 was not on the leading edge.P-40 was behind the curve already by mid-1941? Certainly by mid-1942.
Reason why it was so had a lot to do with the reasons why the Spitfire and Bf 109 remained competitive until the end of the war - the (non) installation of the more modern & more powerful engines.
I can't imagine it roaming the skies of Coastal France or Belgium in 1941.I cannot imagine the Gloster F5/34 by any stretch of the imagination as a fighter that would roam the skies of Germany in 1944.
The French had 4 other "light" fighters under development in 1939-40. All had problems. Many were fast but comparing to the MS 406 kind of tilts the playing field. They also used small wings which kept the drag down but didn't do much for their altitude performance. Speed in thrust vs drag so small (tiny) airplane looks good. But climb is power to weight and really low power vs low/medium weight means poor climb.neither Russell nor Bell nor Italians
Pretty much.If we split the P-40 into airframe and engine then the P-40 airframe was still on the curve in 1941-42-43. It may not have been on the leading edge but anything that wasn't P-51 was not on the leading edge.
That time frame - late 1942/early 43 - is the problem. Adversaries of the P-40F were never powered by MerlinsThe engine wasn't.
But the P-40F wasn't that far off most of it's adversaries in late 1942/early 43 at which point they stopped putting 1940/41 Merlins (single stage two speed) in them.
A better P-40 is a coulda/shoulda argument but a lot of it's opposition (planes with V-12 engines of 1100-1400hp) were smaller, carried less armament and often had less protection.
Yes, the S/C on the V-1710 was a weak spot of the otherwise good power section.The P-40 was let down the Allison engine (or rather the supercharger of the Allison).
The P-40 was also blessed/cursed by the M2 .50 cal Browning. A lot of weight to haul around.
P-40s with 4 guns were fairly common.
There were very, very few Italian fighter built with two 20mm and two 12.7mm machine guns.
Most were doing well to have two 12.7s and two 7.7mm guns and the Japanese were sort of in the same boat.
The Ki-61's with the Japanese Ho-5 20mm guns don't show up until early 1944. Granted the 388 planes with the German MG 151s show up earlier.
Ki-44s with 4 12.7mm guns have no firepower advantage.
The Ki. 84 is issued in the Spring of 1944 to it's first unit.
We read that the Ki 61 II KIA was an "outstanding interceptor" with a speed of 379mph at 19,645ft which is 9-15mph faster than 6 gun P-40F (Kittihawk II).
Of course the Ha 140 engine often did not work well. The Kittihawk II under test also managed 347mph at 30,000ft.
One does wonder what one of the Stripped P-40Ls would do using WEP power for climb?
Or if they could have gotten a few hundred pounds out of the plane by using aluminum radiators/oil coolers and deciding they didn't need to carry 1500-2500lbs worth of bomb/drop tanks under the plane?
Soviet fighters are fast but most of the Yak's are lacking in gun power. Might not be much worse than the four gun P-40 but not much better either.
Some sources (Curtiss factory?) say that the P-40Ls were good for 370mph at 20,000ft. Granted the range sucked but they still held 454 liters.
P-40Fs could hold 594 liters.
Most of the other contemporary fighters also could not do the other stuff (non air superiority ) that the P-40 could do.
For an over 8000lb airplane the P-40 was doing very well for the power it had.
Why it got to over 8000lbs with that small engine (under 1400lbs?) is a different question
We keep falling into the displacement trap. It is possible to compensate for small displacement with RPM at the fundamental stage (initial design/development).V-1710 was also a small engine, so the weakness of the S/C will be felt even more.
Very true. Weight is rarely a good thingVs. the Japanese opposition, the power/weight ratio of a P-40 is also bad.
It isn't. But if you are trying to compare climbs to 15,000 or 20,000ft and light plane X is getting to 20,000ft 2-4 minutes quicker than fatty plane Y when plane Y is using "standard" power then WEP can equalize things a bit for the "enemy bombers spotted 9 minutes away from the air base" scenariosUnfortunately, WEP is of no help above 12 - 15K feet
This does vary a bit from Air Force to Air Force and over time. In 1942 and some of 1943 the US needed general purpose planes. They didn't have the men (flight crews/ground crews) and the number/size air bases they needed in some locations for specialized aircraft. Unless you consider using P-40s as 'top cover' for P-39sFrom a fighter aircraft, people were expecting it to be very good/excellent in it's primary role. When a fighter was relegated to the fighter-bomber duties, that was a good sign that it was found lacking in it's primary role, with other types being better.