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A lot of Russian aircraft suffered from poor details or finish. The Mig also suffered from a number of handling problems, The Mig 3 being better than the Mig 1 but the Mig was still a handful compared to the other new soviet fighters.
The usual Russian response to trying to improve performance, given the limited power of the engines, was to lighten the load (basically armament). Economics also had something to with it as the Shkak 7.62mm machine gun was expensive to manufacture. The 12.7mm UB was cheaper (fewer man hours) so one 12.7 often replaced two 7.62s. Cost of the 20mm Shvak is unknown but it may be cheaper than western weapons. Russians still needed them in large quantities. 10000 fighters with one 20mm each or 5000 fighters with two 20mm guns each?
Both the M-106 and M-17 were prewar projects, It was the failure of both engines that meant the M-105 had to be retained in production despite low power and less than ideal solutions found to keep performance within competitive limits.
The AM-35/38 series were large slow turning engines. They really needed bigger airframes than the existing Russian fighters.
But with the wood construction the airframes were heavy for their size.
Using the weight comparison of the ASh-82 doesn't take into account the physical size of the engines or were the center of gravity of the engine is in relation to the center of gravity of the aircraft.
Please note that the cylinders/crankcase is under the pretty much cylindrical part of the cowl and the tapered/curved part is pretty much empty (long nose case and fan) so the engines real weight is pretty close to the leading edge of the wing.
Sticking in a AM-35/38 engine that is both longer and heavier than the M-105 engine may be a lot harder.
(my emphasis)
Exactly why I've mentioned the AM-38 and M-82, to be installed in fighters as early as possible.
BTW, that extra 5000 fighters, each with single cannon, will still need, say, 10000 of Skash MGs. The Soviets were installing in the I-16 two cannons as early as 1937, along with 2 LMGs, and 4 (four) cannons in 1939, so my proposal means saving, not expense.
Typo - you've meant the M-107? The M-17 was predecessor to the Mikulin's engines. The early application of more powerful and available engines means those Klimovs are not dearly needed. Both M-82 and Mikulins have had much more growth potential than Klimov's, where M-107/108 were brand new engines vs. M-105.
Indeed, the, say 10% bigger engine for a fighter with such a heavy and powerful engine. Much of the engine weight is compensated by having the cooling system behind the CoG, not applicable for radial engines. The ASh-82 does not have the fan, but a segmented shutter that prevents overcooling of the engine, the idea was a carry-over from I-16.
An I-16 with FOUR cannon? in production? Out of over 9000 I-16s built only a little over 700 had the cannon. And the "last" 650 had two 7.62 and one 12.7mm (there was probably some overlap of production between the last models)...
Trouble is that the M-38, the M-106 and the M-82 are pretty much contemporaries. Work started on the M-106 in 1938 and on the other two in 1939. The M-106 was NOT a new engine and in fact would fit standard M-105 mounting points. two were fitted with 2-speed superchargers in 1939. Apparently development did not go smooth and while some were fitted to production Yak-1 fighters they were removed and the planes fitted with M-105s. The M-106 did not go into service until 1944 and then in modified form.
Work on the M-107 started in March 1940. According to preliminary planning the service interval was to reach 100 hours by May 1st 1941 and 2000 M-107 were to be completed by the end of 1941. Things went badly from there on out.
May 13th 1941 saw the NKAP issue a production decree for the M-82.
The M-38 was in production (small numbers?) in the beginning of 1941 although the engine didn't pass it's state tests until July of 1941.
Obviously in preliminary designs and production planning the M-106/107 would have the inside track as so little needed to be changed. Not until they fall on their faces does the need arise for alternative engines and by then the Germans have invaded and pre-invasion production plans are tossed out the window.
Claiming the Russians made a mistake in NOT switching to the M-82 and M-38 sooner doesn't hold up very well as both engines were in development/testing at the time the decision would have to be made. If either one had also run into trouble things would have been really sticky (M-82 was the 3rd 14 cylinder radial engine worked on by Shvetsov and team)
Unfortunately that is not backed up by the text or other sources. Even the table itself has a contradiction in the fact that the type 18 with a heavier engine was lighter than the type 17 with two cannon and 2 machineguns.The I-16 Type 18 was supposed to have 4 cannons aboard, per table in Yefimov & Khazanov book on Soviet fighters.
The AM-38 also fits on mounts for the AM-35A, or at least the installation on the MiG-3 didn't make problems to that end. The Mikulin was also not to be undone, they were testing AM-37 (a bit bigger S/C, intercooled; with problems) and AM-39 (2-speed supercharged; problem free?) with 1500 HP at 5.8 km (~18700 ft) and 1650 HP at 1 km. Pretty much out of scope for Klimov's engines.
There is also nothing that prevents Mikulin to install 'mid altitude' S/C drive on the AM-38, to gain a bit at altitude and loose a bit at SL.
The VK-106 offers mere 50 HP more than M-105, nothing to gain there. A reason why Klimov's team moved on M-107 and M-108?
Russians tested many of their aircraft with different engines that were in pipeline. So I'm not that convinced that testing fighters with the two engines I've suggested would've interfered with then current practice, and allows for reasonably fast switch to the engines that are in actual production while offering power at desired altitude.
It does not take that much of hindsight to reckon that there is far more stretch in Mikulin's engines than it is in Klimov's.
Although Lavochkin had a great deal of success when he swapped the M-105 out for the ASh-82, transforming the LaGG-3 into the La-5...It is one thing to test an engine in an airframe, it is another thing to actually make a usable fighter out of the combination.
Switching engines is a lot easier on bombers where there is more room to play with equipment to get the CG correct. It has been done on fighters but sometimes we are not aware of some the changes done to get things right. On a P-36 the fuel tank behind the seat was the overload ferry tank. On the P-40 (early) the behind the seat tank was a "normal" tank to be used in combat and one of the in wing under cockpit tanks became the overload tank. P-40s shifted oil tanks around as the engines changed (from behind seat to behind engine?)
Again it is easier to play with large fighters (Hawker Tempest) than small fighters.
...
Actually what we have here is a fair amount of confusion as to what was promised and when. I haven't seen any power figures for the M-106 for the early stages of the project (1938-39) when the M-105 was offering 1000/1100hp. it was 1943 before they stuck any in production planes (and didn't fly them) and by that time much modified M-105PF had been in production for months and the M-105PF2 was being tested in July of 1943. At this point the M-105PF-2 is 50-60hp behind the V-106 but we don't know the power difference in 1940. The book on Russian engines doesn't mention altitudes (at least not often) so comparisons are also hard to make on that score.
The M-107 was a sort of parallel development started in 1940 with a lot of modifications (including 4 valve cylinder heads) and supposedly 29 were built in 1941 and 686 total by the end of 1942. What they went in (if anything?) I have no idea at the moment, power was supposed to be 1200/1400hp for a weight of 765Kg but again, altitude information is lacking. The 1942 test version (M-107A) was rated at 1500/1600hp for 769kg and used Ploikoviskiy's blades on the inlet to the supercharger, this engine got into Yak-9s in 1944.
It is one thing to test an engine in an airframe, it is another thing to actually make a usable fighter out of the combination.
Switching engines is a lot easier on bombers where there is more room to play with equipment to get the CG correct. It has been done on fighters but sometimes we are not aware of some the changes done to get things right. On a P-36 the fuel tank behind the seat was the overload ferry tank. On the P-40 (early) the behind the seat tank was a "normal" tank to be used in combat and one of the in wing under cockpit tanks became the overload tank. P-40s shifted oil tanks around as the engines changed (from behind seat to behind engine?)
Again it is easier to play with large fighters (Hawker Tempest) than small fighters.
- too much of engine projects in design phase, with no two stage supercharged engine before too late
- not enough of emphasis for long range fighters (backfired not just for battles in W. Europe, but also for Eastern fromt and MTO)
Drop tanks under 109Es would have done wonders in the BoB.