Hello Vanir,
I have to desagree on some points.
Klimov M-105P was a derivative of the Hispano 12Y motor so it was a natural transition. At around 90cm boost (1.2atm) it's got similar output as the early Merlins (ca.1150hp WEP, 1100 military) and is rated for basic 80-87 octane. From what I've read Soviet fuel quality was poor in 1940-1. Two speed supercharger gives good performance at 1000 and 3000 metres but it performs poorly above 4000 metres and has no automatic boost regulation.
Klimov engines were intended to use from 91-92 to 95-96 octane graded fuels from the M-103 model. All were qualified at 94 octane number during state trials.
The
M-105P was rated at 1100 hp for take off in 1940.
1020 hp at nominal boost 910 mmHg at SL
1100 hp at 2000 m
1050 hp at 4000 m.
Some docs give 920-930 mmHg for the
M-105PA at nominal at SL.
But this is a kind of rethorical problem, all pilots actually used 950 mm hp for M-105 engines from 1941 for nominal (no time limits) regime.
So 1150 hp for Klimov, it's from western (finish, german ?) sources, since no modification occured in official soviet 1939's charts for the 105P, PA, RA series...But it's certainly closer to the truth than outdated soviet chart's.
I don't know what do you mean by
WEP, Military etc cause neither Hispanos nor Klimov had WEP, combat, military or any extra over boosted power of any kind until the Klimov 107A appraisal. Only "nominal", that can be translated by "normal" or "max continuous course" power.
The M-105PF (ca.1320hp WEP, 1260 military) was a recalibration for high fuel grade (100 octane) with 110cm maximum boost iirc (1.47atm). No other modifications were made to the basic engine.
Soviets had no 100 octane fuel until late in war,except from Lend Lease deliveries. With standard 94 one (in fact real octane number 91-92) the
M-105PF gave in spring of 1942
1210 hp at SL at 1050 mmHg both nominal and T.O. (In fact it had no T-Off. overboost)
1260 hp at 0700 m
1180 hp at 2700 m
Boost calibration for the M-105 continued to be adjusted as Soviet fuel quality improved later in the war. By 1943 boost was up to 115cm (PF2 motor) and finally in 1945 to something like 118cm (PF3 motors fitted to Yak-3), for a final return of some 1360hp military (2600rpm) and ca.1430hp WEP (2800-3000rpm) for a minute or two.
The
PF-2 gave in mid 1943
1290 hp at SL
1320 hp at 0300 m
1240 hp at 2200 m
all with 94,5 octanes fuel at nominal, since it had no more WEP or military or combat rew as usual.
The 105 PF-3 only exists in western old sources and
might be (who knows?) in Klimov's design bureau drawing boards and experimental variants...
Some pilots remember 100 octanes (blue) LL use in their front-line Yaks, with a 20 km/h speed gain and some overheating. But nothing official issued from soviet industry.
All of these are basically the same engine with the same supercharger and anciliaries (I think the PF3 made some other changes so is kind of a hybrid with some VK-107 parts), the only major difference between M-105P, PF and PF2 motors is essentially boost recalibration for different fuel qualities and later towards the end of '42 improved pistons were fitted.
False, the 3Б-78 (and 4Б-78 used on M-82) soviet fuels always had 93-95 (and 95-96) o. number from 1939, with some quality fall to 91-92 in some midwar deliveries.
Klimov motors captured during 1941 will invariably be M-105P, the PF started to appear after July '42 but the Leningrad front was very quick to adopt these, later series LaGG were flown sometimes straight from the factory without so much as a paintjob to the area. And existing 105P were recalibrated from this time at the field.
Don't think so, serial 105PF had modified crankshafs, moving weights dispatching and slightly compression rate reduction, due to modified piston and p- bearer design. But if you have some concrete examples...
There were problems with the lend lease Hurricanes and Merlin engines had to be derated during '41 to use local fuel. Also they had to be drained of all fluids and serviced using local products or else they stopped working when temperatures plummetted. Some were just stripped of their armoured seats and radios so these could be fitted to local a/c like the LaGG and Il2.
Given the timescale of captured M-105 motors fitted to Finnish Moranes I'd have thought the PF motor was most likely, only training sqns would have the P because its recalibration was very simple and could be performed in the field, essentially once the authorisation for higher boost was given in mid-42 everybody ran around recalibrating their existing aircraft, as well as all new models coming from the factory featured the new boost calibration. The transition of 105P to PF was essentially only one of fuel quality.
Where could they taken the 105PF from? Finish sources quote captured airwothy 105P, certainly ex german captured from 41 to 42. Moroever 105PF reduction gear axis was about 100 mm higher than the previous 105P (from Yak family specialists: Stépanets, Kuznetsov). It's generally forgotten in plastic kits. So for the 100 mm wing move aft from the Yak-1 to the 7. You have to redesign your plane's nose for that.
The Morane is much like a Hurricane in build, being mixed construction and designed in that era. I guess fitting one with a ~1300hp Klimov makes it fairly similar to a MkII with poorer altitude performance. It's a bit of a jump from the 12Y31 in the MS.406 in any case, which is roughly a ~900hp motor.
I think of the Klimov as very much like an Allison in the P-40, generally underrated because of its altitude performance but otherwise actually a very contemporary high performance aero engine.
I think that the Klimov was a tremendously better engine than the P-40's Allison at low hights and max continuous power*, with the same octanes numbers fuel.
* Considering that fair condition, Hispano-S were not far behind german or british best engines in 1939-40.
Regards
