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First, don't trust Wiki.So here again, M.20 looks better to me.
The Fw190 and Me262 both had full-view canopies, the Me309 also had a canopy based on the Me262's design.To steer this back to aviation, it can maybe be said that the IJA and IJN were a bit ahead of the Allies (and other Axis powers) in using all around vision canopies on their fighters. However, that's mixed, because some had them (Zero, Ki-43, a good number of Ki-27s) and some didn't (most Ki-61s, production J2Ms, etc). Oddly, USN fighters didn't get bubble canopies until the F8F Bearcat and the Goodyear Super Corsair (though a version of the F6F was designed to use one, but never made it into production).
But the IJA and IJN planes that had the bubble canopies had them as early as 1940, maybe even earlier. The Hawker Typhoon wasn't flown with one until 1942, and wasn't standardized until 1943. A Spitfire VIII flew with one in 1943, but Spitfire FR 14s and F 16s didn't get them until 1944 (and it took until after the war with the F/FR18 and F22 to standardize). Even the iconic P-51D Mustang didn't fly in prototype form until 1943, and enter production in 1944. It also took a while for P-47s to go from razorback to bubble top.
Ironically, the Miles M20 "emergency fighter" had one in 1940, and even the 1937-38 era Gloster F5/34 had a bubble-ish canopy.
First, don't trust Wiki.
They don't agree, 20,000ft in 9 minutes 36 seconds averages 2,083fpm.
- Service ceiling: 31,400 ft (9,600 m)
- Absolute ceiling: 35,500 ft (10,800 m)
- Rate of climb: 3,200 ft/min (16 m/s)
- Time to altitude: 20,000 ft (6,100 m) in 9 minutes 36 seconds
The Machine gun armed Hurricane IIs would hit 20,000ft in around 8.5 minutes, they also had ceilings several thousand ft higher.
British times to altitudes were done at a 30 minute rating, for Merlins that often meant 2850rpm and 9lbs of boost (individual aircraft varied a bit on boost)
Without knowing the conditions of the 3200ft/min climb of the M.20 things look a bit dubious.
You can get Hurricanes to climb faster than 2700ft/min, just use 3000rpm
Somewhere the M.20 was noted as having a not too nice stall. Let's also remember that they were NOT thinking of use the M.20 as a normal carrier fighter.
They were thinking of using it as CAM fighter, catapult launched and ditching at sea, one idea was to detach the landing gear when the plane was mounted on the catapult and since the plane was going to ditch in the sea anyway the landing gear needed to be jettisoned. Page 293 of the "British fighter since 1912."
Maybe they have it wrong but there seems to be a crap load of contradictory information about this airplane.
Something else that doesn't line up well.
You have 1888lbs of "pay load" but you have 1108lbs of fuel. which leaves 780lbs of weight for the oil (76lbs) , the 200lb pilot, the radio gear (just over 100lbs) and oh yeah, the guns and ammo (571lbs?) and bit of misc (flares. gun sight?)
- Empty weight: 5,870 lb (2,663 kg)
- Max takeoff weight: 7,758 lb (3,519 kg)
- Fuel capacity: 154 imp gal (185 US gal; 700 L) fuel
Either the thing carried less fuel, or it carried less ammo or they raised the take-off weight or a combination. BTW the Spitfire and Hurricane used about the same amount of oil for 85-84 gallons of fuel so the oil weight is off for 154 gallons.
Ok, we have talked about "hot and high" conditions before. Everybody's aircraft did worse in tropical conditions. some did somewhat worse and some did a lot worse but,Like I said, maybe in England, they didn't seem to in Egypt or Rangoon.
Apparently it never did 350mph. It may have been an estimate?And if it makes 350 mph with feet sticking out, how fast it is with retractable landing gear?
Ok, we have talked about "hot and high" conditions before. Everybody's aircraft did worse in tropical conditions. some did somewhat worse and some did a lot worse but,
Chances of plane A being better than plane B in England but worse in Egypt or Rangoon are about zero.
The M.20 was only tested in England and the British usually tried to modify the test results to "standard conditions" (59 degrees F and standard pressure).
Apparently it never did 350mph. It may have been an estimate?
British Fighters from 1912 says the modified version only did 333mph under test, the same as the unmodified version. Modified version was supposed to have a more streamlined spinner nose, the smaller landing gear and the catapult spools. Not sure what else was different.
Basically the M.20 was not faster, it took longer to climb to 20,000ft carrying eight .303 guns than the Hurricane II did with four 20mm guns, it had a lower ceiling and needed more runway, maybe only bit.
If it won't perform well in trials why would anybody believe it was going to do better in service?
The British did make some mistakes in procurement. The M.20 was not one of them.
Well, the P-40s didn't get tropical filters or got a much simpler one. The P-40s that got them could cut them in and out during flight. Not sure about the radiators, The British had a entire tropical package which often gets shortened to just "vokes filter". Tropical package included such things as emergency rations and survival gear, they may have swapped out the dinghy?That would seem not to be the case - the P-40 clearly lost less in terms of performance from it's baseline, and did fairly well in North Africa, whereas the Hurricane did not. This is one of the main reasons why the British ultimately decided to double down on the Kittyhawk as their main fighter for the region, even though it meant a much more complicated logistics tail for them. In part this was because it was apparently easier and less troublesome / performance crippling tropical filter for the engine, (both the Allison with the air intake on the top, but also with the Merlin XX for reasons I still don't fully understand), But it also apparently had something to do with the physical characteristics of the aircraft, the wings or something.
The Wildcat also seems to have lost relatively little in terms of performance in the tropics. Which may be one of the secrets of it's somewhat inexplicable success.
The P-39 seemed to be the opposite, and performed much better in cold weather environments .
They don't seem to have fitted the test airframes with any extra stuff. Even the 12 .303s may have been a bit speculative. Hurricanes got a bit of a double whammy with the 20mm guns, the four 20mms and ammo weigh around 170lbs more than twelve .303s but the 20mm guns on the Hurricane have got to be about the highest drag installation of any four 20mm gun installation seen on a single engine fighter. There is a reason the Spitfires got fairings.But here is the thing. Fixed undercarriage imposes quite a drag burden. Like 20-30 mph at least. So if the top speed is ~330 mph with fixed undercarriage I'd expect 350-360 without, even with a "full combat load" and antennas and bomb shackles and extra gun farings (once they put in 20mm) etc.
See above, not quite comparing apples to apples.Hurricane IIC with tropical filters were just barely making 300 mph in the Western desert,
OK you got me. M.20 Taking 1 minute and 6 seconds longer to climb to 20,000ft proves the M.20 had a superior climb rate to the Hurricane IIA or IIB.I don't think you have proven that it had inferior rate of climb, at least not yet. It did seem to have a lower ceiling.
I rather like the Whirlwind, I just doubt that you could hang two Merlins on plane that had a wing 6.8% bigger than the plane (M.20) in question.Well I think it could have been very helpful. We disagree on the Whirlwind too!
Well, the P-40s didn't get tropical filters or got a much simpler one. The P-40s that got them could cut them in and out during flight. Not sure about the radiators, The British had a entire tropical package which often gets shortened to just "vokes filter". Tropical package included such things as emergency rations and survival gear, they may have swapped out the dinghy?
British would have stuck a filter on the M.20. There was quite a bit of trouble with the P-40F with the Merlin engine, in part because it had no filter. In part because the US didn't order enough spare engines to begin with (or rather didn't allocate enough engines as spares). The British are supposed to have given 600 used Merlins to the US to provide spare parts for overhaul but we know this cannot be true because the British Merlins weren't built to the same tolerances as the Packard Merlins
P-39 had several differences, the smaller wing for one, and that air intake seems to have needed help. in test reports the nominally identical engines in the P-39 and P-40 always seem to have a bit lower full throttle height in the P-39, and this is with the P-39 flying faster which should give a bit more RAM. It may need more investigation.
The F4F has a big wing, about the same as the Hurricane and it also has the two stage supercharger so you have more power at the higher altitudes. It is still going to worse at 20,000ft in hot air but you may have a bit of compensation by the supercharger and intercoolers.
They don't seem to have fitted the test airframes with any extra stuff. Even the 12 .303s may have been a bit speculative. Hurricanes got a bit of a double whammy with the 20mm guns, the four 20mms and ammo weigh around 170lbs more than twelve .303s but the 20mm guns on the Hurricane have got to be about the highest drag installation of any four 20mm gun installation seen on a single engine fighter. There is a reason the Spitfires got fairings.
See above, not quite comparing apples to apples.
OK you got me. M.20 Taking 1 minute and 6 seconds longer to climb to 20,000ft proves the M.20 had a superior climb rate to the Hurricane IIA or IIB.
I cannot argue with that logic.
I rather like the Whirlwind, I just doubt that you could hang two Merlins on plane that had a wing 6.8% bigger than the plane (M.20) in question.
Now we get into arguments as to "easily modified" really means.
It wasn't all good news with the change to the Seafire 47 intake.The discussion on aircraft in the MTO is obviously worthy of it's own thread. However, Hurricanes and Spitfire Vs did use the big Vokes filter commonly in the Pacific, which the main problem with it was that the fairing for it produced a lot of drag. And I mean a ton, as in it could knock as much as 8-10% off a plane's top speed potentially.
Of course, the Spitfire IX/VIII and the Mosquito did a lot better with integrating air filters into their intakes (just an extension of the supercharger intake essentially). Other designs did it better, though (at least in my opinion). The Merlin Mustangs with their ram air supercharger intake that began just behind the prop spinner was long enough that the filters could be just added internally to the supercharger intake trunk (that's what the cheese grater panels were on P-51B/C/D/K/H and F-82s were).
Also interesting was that the later Griffon powered Seafires (namely the Mk 47) used a similar intake (though without the side mounted filter intakes), the Spiteful/Seafang went back and forth between a Spitfire XIV/22/24 supercharger intake and a Seafire 47 type intake, and the Sabre powered Hawker Fury had a Mustang type under spinner intake (outer sections fed the oil coolers that were mounted at the back of the engine, center section fed the supercharger, which had filter intakes on the underside of it).
I also believe that the cheese graters on the side of the noses of P-40s were air filters.
All you need to know about the Vokes filter on the Spitfire is here (including the extra oil tank needed in the tropics)Didn't the Vokes filter also carry a lot of oil? (I don't know why it would, but I remember reading that somewhere... possibly hallucinated)
AFAIK there was not a general switch to the Aboukir type. It was purely a local modification made in Egypt.Thanks. it's quite interesting that the real problem was mainly the elmination of the Ram air effect. Do you know when they switched over to the Aboukir type?
The interesting conclusions that the author draws is that long range torpedo fire was not a winning proposition. The most successful torpedo attack was Tassafaronga and there the torpedoes were launched at close range, certainly with range of US torpedoes.Perhaps drifting too much into naval stuff, but the above is very interesting, any explanation why they chose a 6000 ton design instead of an 8000 ton one?
Good read, however inevitably one can see a bias there. Adding the 1943-44 torpedo launch/hit figures when the IJN was increasingly loosing it's edge due to ship and men losses, faced with an ever increasing and adapting USN is a bit misleading imo. Rather the 1942 statistics, when IJN was at it's peak are a much better indication as to how the hypothetical decisive battle could have went. Note that in 4 of the 6 battles with a large numbers of torpedoes launched (i discount the below 10 numbers for now), IJN scores hovered around 12-13%. The outliers are Java sea (launched from too far?) and second Guadalcanal (not quite sure what happened there, just pure luck for the american BBs not to be hit?).
If the IJN has a really good day during this hypothetical kantai kessen and the hits are hovering in the region of 12-13%, they might just about pull it off!