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You can get it here:Hey tomo pauk and RCAFson,
Thank you. Can either of you provide me with the appropriate DTIC document link? This appears to be one I have not run across before.
Re the japanese engines, actually 2 speed engines were definitely in service in 1941, the Kasei/Ha-101 (G4M1, Ki-21-II) and i think the Ha-102 too (Ki-46-II, Ki-45 Kai) with production already starting in 1940 iirc (need to have another look at the USSBS reports)There is more than one path to follow.
The Soviets followed different paths, They took the 36 liter Hispano (bigger than the DB 601 and almost the same size as a Griffon) and beefed it up, put a 2 speed supercharger on it used it with the 96 octane fuel. The Hispano was a very light engine and that limited it's power.
The Japanese seemed to be trapped by old style thinking, like there were two types of engines, big heavy bomber engines and smaller, lighter fighter engines. It took too long to start figuring out how to put the big bomber engines in a fighter.
The Soviets also sometimes went for brute force. The Shvetsov M-82 (41.2 liters) first ran in 1940.
For some reason the Japanese failed to really develop the Nakajima Ha-41/Ha 109 of 37.5 liters. Or any of the other larger 14 cylinder radials. They stayed wedded to the small diameter engines which offered better streamlining. What was actually promised I don't know put what was promised failed to be delivered.
At any rate none of the Japanese engines got two speed superchargers into service until about mid 1942 and many of the engines didn't go into wide spread service until the end of 1942. beginning of 1943. By with time for the US only the Allison was in service with combat planes (float planes excepted) with a single speed supercharger or rather in production aircraft.
Re. Soviet 96 oct fuel - 96 was lean rating, how good was rich rating? We know that German C3 was 96-100 oct lean, 120-140 PN rich; British 100 oct fuel from BoB was 100 oct lean and ~120 PN rich?The soviets never made anything over 96 octane in quantity during WW II. They sometimes needed help with additives.
The Soviets just used larger engines of similar weights to some of the western engines.
The Mig 3 used that large, heavy AM-35A engine BUT it made 1150hp at 7000 meters according to one source and did it on 96 octane fuel instead of the 100/130 that the Merlin 46 needed to get into the same area.
your other choice is to make a two stage supercharger (with intercooler) and run try to run combination of under 100 octane fuel.
The Japanese seemed to be trapped by old style thinking, like there were two types of engines, big heavy bomber engines and smaller, lighter fighter engines. It took too long to start figuring out how to put the big bomber engines in a fighter.
The latest G3M bombers, Nakajima production starting in mid-1941, were powered by 2-speed supercharged Kinsei 50 series.Re the japanese engines, actually 2 speed engines were definitely in service in 1941, the Kasei/Ha-101 (G4M1, Ki-21-II) and i think the Ha-102 too (Ki-46-II, Ki-45 Kai) with production already starting in 1940 iirc (need to have another look at the USSBS reports)
Biggest flunk was Mitsubishi messing around with that extended shaft which caused all kinds of problems, otherwise a normal Kasei installation in the Raiden could possibly allow it to get at the front in 1943.Re. Soviet 96 oct fuel - 96 was lean rating, how good was rich rating? We know that German C3 was 96-100 oct lean, 120-140 PN rich; British 100 oct fuel from BoB was 100 oct lean and ~120 PN rich?
Army was reasonably fast to have a big radial on a fighter, the Ki-44 1st flew in August of 1940.
Yes, Navy (Mitsubish) flunked with installing the Kasei on a fighter.
Just noticed Shortround's tagline of ballistic wisdom. Much like "Aim small, miss small!"The maneuver vs speed argument has gone in a number of directions including this one.
My thought is that the 1942 A6M2 and Ki-43 had basically 1940 performance and armament. It did not get a lot better as the war went on. Perhaps they closed the gap to one year?
Criteria are in squadron service aircraft, not prototypes or service test.
The early fighters had great range, they sacrificed things to get it (firepower and protection).
Many other Japanese fighters did not have a range outside the range that is "normal" for the fuel capacity/speed for other fighters.
The Japanese were always behind in armament, and let's not go by barrel count but actual fire power.
The Japanese did face several handicaps. One was fuel quality, but you can't just pour in Allied fuel and get allied power levels. You often need better materials (another short coming ) and better cooling, which also may require changes in tooling and/or basic structure.
Another handicap, faced by many of the smaller nations, was the size of the engineering force. Not "Idea men" but the engineering grunts that did the stress calculations and other calculations and the draftsmen to do the drawings. Some fighters had tens of thousands of parts and each part needed at least one drawing and sometimes several. A larger company or company in a larger country can complete a project in less time due to the greater resources that can be used to bring the project to completion. Has nothing to do with talent or skill of the designer (or design team).
For Japanese army fighters
The Ki-43 II entered service in Dec 1942/Jan 1943
The Ki-44 entered "service" in late 1941 but they only built 50 of them until the service Ki-44 II showed up in Dec 1942?
Ki-61 entered service in Dec 1942/Jan 1943?
Ki-84 showed up in actual service (not trial unit) in the summer of 1944.
Well, japanese publications seem to suggest the G3M3 entered production in middle of 1942, so it's a bit confusing. If there is clearer info on the subject by all means would be good to see.
Biggest flunk was Mitsubishi messing around with that extended shaft which caused all kinds of problems, otherwise a normal Kasei installation in the Raiden could possibly allow it to get at the front in 1943.
Same with the Kyofu, first they messed around with contraprops, then with the extended shaft, then i believe finally a normal installation for the Kasei-15?
Same sort of story with the Ki-44, instead of going full production when it was ready about fall/late 1941, they only built 50 of them until fall 1942, until the Ki-44-II came along. Even couple of hundred Ki-44s built in this period means couple of Ki-44 Sentais (as opposed to just a meagre experimental chutai) available for the early war operations. As i understand the Ki-44 was more than a match for a P-40 or Hurricane, nevermind F2As, H75s etc.
PS: And same vaccilation and repeated redesign plagued the Ki-45, it took almost 3 and half years from prototype to service, whereas even the Ki-43 took merely 2 and half. Again a case of best being the enemy of good enough, the "good enough" initial redesign Ki-45 with Ha-25 engines could have been in production in 1940 even as an interim until the definitive Ki-45 KAI was ready.
Question(s). Was not the R2800 in the P-47 making peak power well over 2000 by mid/late 1943? Did not P&W run it on test stands at very high power outputs 3000 or so for hours continous?. Now cooling would be an issue in cowled engines, I don't know how the engine stand engines were cooled. But obviously the basic engine was capable of a lot more power output than was used even on the M and N models. Was it not true that P&W and/or Republic were sending techs to England to help the crew chiefs hotrod the turbochargers? I have read after action reports of P47 pilots in late 1944 out climbing Me109s at low altitude. Johnson said the up grades to his P-47 let him out climb the competition. This is not going to happen with 2000 or 2100 HP. Yes WEP needed water/methanol for COOLING the intake charge. Robert S Johnson reported indicated airspeeds at high altitude with his (hot rodded) P47D that were close to M speeds. And he did not have an "entirely new engine" SFAIK. Just wondering where you get the info since virtually all the Republic paperwork from WW-II was destroyed back in the 1960s or early 1970s. If I am correct. So unless there are military manuals on the various engines used and their specs I don't know where to get this data. But the M and N were using 2800 HP WEP R-2800 and the Increase in octane by abpit late 1943 to 145/150 greatly increased the allowable manifold pressure. This greatly increased the WEP level and then we have to ask at what point did they have to Use the water injection.You did, basically altitude and cooling.
The Merlin III made 1310hp using 12lbs of boost at 9,000ft, the 1030hp was at 16,250ft.
Liquid cooled engines usually had more head room for power increases. The air cooled engines were operating closer to the detonation limits.
I would note that for major US radials, NO engine was OK'ed for WEP without water injection. Also NO engine was rated at increased power levels (subject to supercharger limitations) without a major changes in engine structure, except the R-2800 when it went from 1850hp to 2000hp. The 2100hp engine in the P-47M was an entirely new engine.
The Ki-45 of 1940 was capable of 520 kph with Ha-25 engines. The IJAAF probably turned it's nose at it because it didn't reach 540 kph as the spec demanded. The completely redesigned Ki-45 Kai (547 kph) was almost a new aircraft, new straight wings instead of eliptical, longer redesigned fuselage, new empennages, powered by the Ha-102 engines, but it only flew in 1941 and entered service in the first half of 1942, and it was a failure anyway as a day fighter, though it found use as fighter-bomber and night-fighter (and day fighter in home defence until allied fighters appeared) .Ki 44 was probably the closest equivalent to the Bf 109 the Japanese ever produced
What kind of performance can one expect from the Ki-45 that is powered by Ha 25 of 1940 vintage?
There is a world of difference between what could be done on test stands and what could be done in the Field. For one thing on test stands the engines were more closely monitored had trouble could often be detected earlier (before catastrophic failure).Question(s). Was not the R2800 in the P-47 making peak power well over 2000 by mid/late 1943? Did not P&W run it on test stands at very high power outputs 3000 or so for hours continous?. Now cooling would be an issue in cowled engines, I don't know how the engine stand engines were cooled. But obviously the basic engine was capable of a lot more power output than was used even on the M and N models. Was it not true that P&W and/or Republic were sending techs to England to help the crew chiefs hotrod the turbochargers? I have read after action reports of P47 pilots in late 1944 out climbing Me109s at low altitude. Johnson said the up grades to his P-47 let him out climb the competition. This is not going to happen with 2000 or 2100 HP. Yes WEP needed water/methanol for COOLING the intake charge. Robert S Johnson reported indicated airspeeds at high altitude with his (hot rodded) P47D that were close to M speeds. And he did not have an "entirely new engine" SFAIK. Just wondering where you get the info since virtually all the Republic paperwork from WW-II was destroyed back in the 1960s or early 1970s. If I am correct. So unless there are military manuals on the various engines used and their specs I don't know where to get this data. But the M and N were using 2800 HP WEP R-2800 and the Increase in octane by abpit late 1943 to 145/150 greatly increased the allowable manifold pressure. This greatly increased the WEP level and then we have to ask at what point did they have to Use the water injection.
So far as the "if " the Japanese had this for that is not relevant. They and the rest of the Axis lost the war when the first bomb fell on US soil Dec 7, 1941. Nothing any of them did after that could change the outcome.
According to one source that I have read it was a lot more complicated than that. Could be wrong.The Ki-45 of 1940 was capable of 520 kph with Ha-25 engines. The IJAAF probably turned it's nose at it because it didn't reach 540 kph as the spec demanded. The completely redesigned Ki-45 Kai (547 kph) was almost a new aircraft, new straight wings instead of eliptical, longer redesigned fuselage, new empennages, powered by the Ha-102 engines, but it only flew in 1941 and entered service in the first half of 1942, and it was a failure anyway as a day fighter, though it found use as fighter-bomber and night-fighter (and day fighter in home defence until allied fighters appeared) .
Presumably the Kawasaki line initially intended to build the Ki-45 stood idle all that time, when it could have build the interim model even in moderate numbers from 1940 onwards, all for the sake of 20 kph. It still wouldn't cope with allied fighters, but at least with the 20mm gun it could shoot down allied bombers and do ground attack etc. in the early part of the war in 1941-42. Interesting to ponder a few of these intercepting or chasing Doolittle's B-25s.
Presumably the Kawasaki line initially intended to build the Ki-45 stood idle all that time, when it could have build the interim model even in moderate numbers from 1940 onwards, all for the sake of 20 kph. It still wouldn't cope with allied fighters, but at least with the 20mm gun it could shoot down allied bombers and do ground attack etc. in the early part of the war in 1941-42. Interesting to ponder a few of these intercepting or chasing Doolittle's B-25s.