# Question on M.S.406



## rousseau (Jan 28, 2009)

Sorry for such question maybe stupid, but I really want to know it.

Some aeroplane equipped engine same as Morane-Saulnier 406 like Dewoitine 520, but I saw a tiny inlet is very closely behind the propeller on M.S. 406. which cause the engine nacelle of M.S.406 looks like a beer belly.
So there is my question, why the engine nacelle of M.S.406 is so ugly? what's the tiny inlet work for?

Thank you in advance.


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## Clay_Allison (Jan 28, 2009)

All around that may be the ugliest monoplane of the war outside of Poland's parasol-winged joke and the sad stupid-looking P-26 Peashooter.


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## Fokker D21 (Jan 28, 2009)

First of all questions are never stupid, not asking is.

If you are referring to the small intake just below the propeller, it is the oil cooler (Radiateur d'huile) which is located directly underneath the forward part of the engine.


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## Graeme (Jan 29, 2009)

G'day rousseau.

I agree with "Fokker D21," the oil cooler. A couple of pics to help identify your "beer belly"...


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## Milos Sijacki (Jan 29, 2009)

Nice pics. Agree with You guys, OIL COOLER. 

As long as we are talking about this plane, can someone tell me what was its combat history and what was it like in combat?

Cheers


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## davebender (Jan 29, 2009)

Off topic but...
What's wrong with the P-26? Was there anything better during 1933 when the P-26 first entered service with the U.S. Army Air Corps?


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## Colin1 (Jan 29, 2009)

Milos Sijacki said:


> As long as we are talking about this plane, can someone tell me what was its combat history and what was it like in combat?


The French had more of these than anything else at the outbreak of war, the contract was placed in early 1938 and production started in late 1938. 

The first example flew 70 years ago today!

By the start of hostilities they had about 550 on strength.
It didn't fare well against the Luftwaffe, the Bf109 outclassed it. It was underpowered at around 300mph and despite the presence of the 20mm cannon was weakly armed. In the short war for the French, just under 400 were lost to about 180 kills in return.
The Luftwaffe themselves took on the remainder of the MS406 fighters, using it for training and I've seen box-art suggesting it was used in combat (Revell 1/32 Supermarine Seafire smoking a Morane-Saulnier 406 in Luftwaffe colours) but I'm not suggesting for a minute that that is a reliable source.
Foreign buyers and benefactors seemed to do better with the type than France did, the Finns used it in their war and one of their aces achieved over a dozen kills in a 406.


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## Captain Dunsel (Jan 29, 2009)

> All around that may be the ugliest monoplane of the war outside of Poland's parasol-winged joke and the sad stupid-looking P-26 Peashooter.



As DaveBender said about the P-26. Likewise, the PZL's were the hottest thing in the skies when they came out. The PZL-24 was faster than the Gladiators, for example, and much better armed.

The Poles and Greeks (plus others) did pretty well with the PZL series.

Oh, and how about the Peashooters that saw combat with China and in the Phillipines?

CD


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## Fokker D21 (Jan 29, 2009)

I wonder why the MS 406 had a semi retractable radiator. Was it supposed to boost speed under certain conditions?


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## Venganza (Jan 29, 2009)

Fokker D21 said:


> I wonder why the MS 406 had a semi retractable radiator. Was it supposed to boost speed under certain conditions?



Probably, to reduce drag under certain flight regimes. And let's face it, the M.S. 406 needed all the help it could get.

Venganza


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## parsifal (Jan 29, 2009)

MS 406s under Finnish control enjoyed considerable success. They were also used in some numbers by the Turks and the Swiss.

From memorythe french lost about 200 in the air (and many more on the ground) whilst achieving about 100 Kills themselves....not an impressive record. I think around 450 were lost during the BOF.

Three (I think) were shipped to Indochina, where they fought in the war with Siam in 1940-41. They appear to have held their own against the H-75 (N) and Hawks of the RTAF


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## Venganza (Jan 29, 2009)

parsifal said:


> MS 406s under Finnish control enjoyed considerable success.



Parsifal, didn't the Finns re-engine or modify them in some way to make them more effective? I remember they called some of theirs the "Morko-Morane". Were these the modified versions?

Venganza


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## Marshall_Stack (Jan 29, 2009)

Venganza said:


> Probably, to reduce drag under certain flight regimes. And let's face it, the M.S. 406 needed all the help it could get.
> 
> Venganza



Interesting idea. I guess this is used in lieu of cowl flaps?


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## davebender (Jan 29, 2009)

Britain fought an undeclared war against France from July 1940 onward. The USA joined the fight against France during the fall of 1942. How did the Ms.406 fare in places like Dakar, Syria, Morocco, Algeria and Madagascar?


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## Milos Sijacki (Jan 29, 2009)

Thanks for the info Colin1.


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## Clay_Allison (Jan 29, 2009)

Venganza said:


> Parsifal, didn't the Finns re-engine or modify them in some way to make them more effective? I remember they called some of theirs the "Morko-Morane". Were these the modified versions?
> 
> Venganza


they put captured Klimov engines in them.


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## parsifal (Jan 29, 2009)

Juha will know the exact progress of this much publicised mod. i am not sure when this happened, and to how many airframes it was done on....but the change in engine brougt about a sizable increase in performance.

The fundamental problem with the Morane was its lack of power. Without the HPs it could not ship adequate armament, protection, and was always struggling performance wise. But there was nothing inhernetly wrong with the airframe, or the aircraft as a concept.


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## Venganza (Jan 29, 2009)

Thank you for the info, Clay and Parsifal! It seems that lack of power was the downfall of many planes. It reminds me of the Macchi C.200 - a good airframe with a bulky, low-power radial. When they put a DB in it, it turned out quite nicely as the M.C.202, and even better when developed into the M.C.205.

Venganza


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## parsifal (Jan 29, 2009)

Therer was one unit of MS 406's in the Levant as of March 1940, however at this stage I can find no evidence of the type being present in April 1941.

The french did not view kindly the failure of the Morane over France in 1940, and were not keen to incorporate it into the post-armistice air force. severely restricted in size, it appears that the major fighter elements of the Vichy air force were the D 520s, H-75s and MB 152s that had survived. There is also some evidence of some post armistice D 520s and MB 155s being received by the Vichy air force

The air fighting over the Levant is nevertheless interesting. The French fielded 279 aircraft for this campaign, including 35 D 520s, and an indeterminate number of Martin 167s. At first they did quite well, but RAAF 3 sqn also acquitted itself pretty well, flying P-40B Tomahawks (I think it was B)

Tomahawks of No. 3 Squadron, Royal Australian Air Force (RAAF), took part in the first attack on June 8, helping to destroy a Dewoitine D.520 fighter and damage three others at Rayak airfield. Elsewhere on that same day, two of No. 250 Squadron’s Tomahawks drew first blood for the P-40 in the air when they shot down an Italian Cant Z.1007bis reconnaissance plane five miles northwest of Alexandria, Egypt. The Vichy French put up a spirited fight before finally signing an armistice on July 14, but the Tomahawks of No. 3 Squadron RAAF also acquitted themselves well, holding their own against France’s top-of-the-line D.520s and shooting down two out of eight German Junkers Ju-88As of II Gruppe, Lehrgeschwader 1, operating from Crete, that tried to interfere with British landings on the Levantine coast on June 12.


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## rousseau (Jan 29, 2009)

to be grateful to all of gentleman here.
regrettably, my question is not end.
Nolessthan three sort of airplanes in the period of WW2 is also use same engine as M.S.406, Dewoitine 520,Arsenal VG.33, and Rogozarski IK-3 for example.
Why I can not see this oil cooler inlet on these airplanes? Does these airplane's axletree not need lube to refrigerate?


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## davebender (Jan 30, 2009)

France, 194... something
Looking at the OOB this appears to be the case. Which speaks volumes about how the French Air Force viewed the Ms.406 compared to other fighter aircraft.

There was a French Ms.406 squadron on Madagascar during the British invasion. Did they fight or sit the battle out?


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## Watanbe (Jan 30, 2009)

I don't think its that bad a plane, the thing when comparing the early war fighters that comes to mind is just how much better the Me109 and Spitfire was compared to rest of its competition. If you consider the designs coming from the US and other parts of Europe (excepting maybe the D.520) it was probably on par!


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## parsifal (Jan 30, 2009)

The MS 406 was actually a 1935 design, so you actually need to compare with the aircraft on the drawing boards in 1935. Except that the French were rather slow in developing new types as a result of their rationalization program. Other countries were developing types in 1938 that were entering service in 1940-41, whilst the French were developing types in 1935-6 that were still only entering service in 1940-41. 
To be fair, by 1939 the french were ovewrcoming their difficulties, and were beginning to developing very superior aircraft, but they were all just a bunch of prototypes at the time of the armistice
So, you need to compare the MS 406 with the foreign types being worked n in 1938-9 if you want to compare apples to apples. That puts the poor od Morane up against the MC 200, IK-3, IAR 80, P-40, P-43, F4f, Lagg-3, Mig-1/3, Yak-1, A6M, Ki-43, FK-58 and domestically the D-520 and MB 152. The british had the HurricaneI and the Spit, and were already looking at the typhoon. Germany of course had the 109.

Against some of these types the Morane was competitive, but as a generalization it had so many weaknesses that it cannot be considered in the top half of its class. Just an example....whilst it boasted a single cannon, and 2 x7.5 mm LMGs in the wing, the cannon carried only sixty rounds and was somewhat prone to jam (similar to the problems faced by the nose mounted cannon in the 109) whilst the 7.5mms carried only 300 rpg and were not heated leading to a marked tendency to freeze above 15000 ft


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## Clay_Allison (Jan 31, 2009)

Watanbe said:


> I don't think its that bad a plane, the thing when comparing the early war fighters that comes to mind is just how much better the Me109 and Spitfire was compared to rest of its competition. If you consider the designs coming from the US and other parts of Europe (excepting maybe the D.520) it was probably on par!


Given the choice, I'd take a P-40 100 times out of 100 over the M.S.406. It had more power, more armament, and was far far tougher. The P-40 killed a lot of 109Es before the 109F established a clear advantage. 

It never did fight well high, but the Moraine didn't have a great supercharger either and would have had to fight in the P-40's element where it was never outclassed (down on the deck).

Also, IIRC, Allied P-40s trashed some Vichy Moraines in Africa.


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## Watanbe (Jan 31, 2009)

yeh fair enough, I personally think the P40 is quite under rated it had its success' in Africa!


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## Vincenzo (Jan 31, 2009)

I don't think it's fair compare MS 406 with P-40, and some of the others indicated to parsifal, at time a year it's a long time.
take out development, first production MS 406 flying january '39, first P-40 april '40, first P-43 may '41, F4F-3 february '40, IK 3 july '40, IAR 80 january '41, A6M january '40, Ki-43 april '41, D. 520 november '39, Lagg february '41, MiG autumn '40 and same for the Yak


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## Juha (Jan 31, 2009)

Some bits of info on FAF (Finnish AF) MS 406s
French gov. donated 30 MS 406s to Finland during the Winter War, first a/c to operations in early Feb. 40, flew 288 sorties, 14 kills, one loss to AAA.
From Germany’s war booty depots Finns bought 10 MS 406s in Dec 1940, 15 in 1941 and 32 in 1942, few of them were MS 410s. Altogether FAF got 87 Moranes. During the Continuation War (25 Jun 41- 4 Sept 44) Morane pilots claimed 121 kills, lost 27 a/c in combat (18 in air combat, 8 to AA, one to own AA) plus one on ground plus 14 in accidents or because of technical malfunctions..
Mörkö-Morane, re-engined with Klimov M-105P, first flight on 4 Feb 43, during the Continuation War two others were modified. Altogether 41 a/c were modified by 21 Nov 44.
Mörkö-Morane pilot(s) got 4 kills, all by sergeant Hattinen, a very daring, one would say over daring, pilot while flying the proto MSv-617. In reality Hattinen shot down one La-5 and one Airacobra. He got the Airacobra when he attacked alone a formation of 30+ Soviet fighters, claimed 2, but in the end he was shot down but managed to jump. He had got the La-5 earlier when he attacked, again alone, a Soviet formation of 6 La-5s and 6 Il-2s.
Morane was very good turner but lousy climber. Poor gun platform. Much technical problems.

On Frech service, MS wasn't helpless but Hawk 75, export version of P-36 series, did better, in fact Hawk 75 was the most succesful fighter of French AF in 1939-40 period.

Juha


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## parsifal (Jan 31, 2009)

Vincenzo said:


> I don't think it's fair compare MS 406 with P-40, and some of the others indicated to parsifal, at time a year it's a long time.
> take out development, first production MS 406 flying january '39, first P-40 april '40, first P-43 may '41, F4F-3 february '40, IK 3 july '40, IAR 80 january '41, A6M january '40, Ki-43 april '41, D. 520 november '39, Lagg february '41, MiG autumn '40 and same for the Yak



Hi Vincenzo

I do basically accept what you are saying, however, note this, in Septmeber 1939, there were less than 70 moranes operational in the French AF. This is despite the fact that they had a two year headstart on most of the types I have mentioned. i know it unfair to compare an a/c developed basically 1935-6 to a/c developed 1939-40, but thats the result of the French aeronautical industry being so innefficient at the time, not because I wanted to make an unfair comparison


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## Vincenzo (Jan 31, 2009)

parsifal said:


> Hi Vincenzo
> 
> I do basically accept what you are saying, however, note this, in Septmeber 1939, there were less than 70 moranes operational in the French AF. This is despite the fact that they had a two year headstart on most of the types I have mentioned. i know it unfair to compare an a/c developed basically 1935-6 to a/c developed 1939-40, but thats the result of the French aeronautical industry being so innefficient at the time, not because I wanted to make an unfair comparison



I can understand your point on innefficiency of french aeronautical industry, but in septemebr '39 there are 70 406 but none of all types that i indicate


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## Von Frag (Jan 31, 2009)

Venganza said:


> Parsifal, didn't the Finns re-engine or modify them in some way to make them more effective? I remember they called some of theirs the "Morko-Morane". Were these the modified versions?
> 
> Venganza



Yes, they re-engined some with a Klimov 105 I think, and used Russian propellers. Top speed did not improve much, but the Morko (Ghost) could climb over 4,000 ft per minute.


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## Fokker D21 (Feb 2, 2009)

I have to agree with Vincenzo. The first P-40's went into service in early 1941 in the DAF (desert airforce) and only saw operational service in the USAAF in July 1942.

It's main opponents were Bf 109 F and G and Fw 190's.


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## Fokker D21 (Feb 2, 2009)

To answer Rousseau's question, my best guess is either on of these two:

1) The MS 406 is the older design. So perhaps in the other designs new developments also led to an improved oil cooler design.

2) The MS 406 has a semi retractable radiator. It is not unlikely that the oil cooler was supposed to do some of the engine cooling as well (perhaps even a significant part whith the radiator retracted). In the Bf 109 about one third of engine cooling is taken care of by the oil cooler. The three other fighters all have fixed radiators.


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## Mangrove (Feb 14, 2009)

Von Frag said:


> Yes, they re-engined some with a Klimov 105 I think, and used Russian propellers. Top speed did not improve much, but the Morko (Ghost) could climb over 4,000 ft per minute.



Hi,

Ghost would be "haamu" in Finnish. Mörkö is more a "bogeyman" or "the Groke" from Moomin.

The speed advance against the original model was improved as much as 10% and climbing speed to 5,000 meters by two minutes from 10 to 8.

Martti


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## waroff (Feb 17, 2009)

I think there is some error:













(from "Notice descriptive MS 406")


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## JoeB (Feb 18, 2009)

davebender said:


> There was a French Ms.406 squadron on Madagascar during the British invasion. Did they fight or sit the battle out?



There was one air combat in Madagascar of Ms406 v. FAA Martlets (F4F's) of 881 Sdn from HMS Illustrious, May 7, 1942. Of 4 Martlets, one belly landed after hit to the engine with 20mm; they claimed 4 Ms406's. Per French accounts only 3 Ms406's were present but all were shot down, 1 pilot killed. 

The French force in Syria in June '41 included 18 Ms406's of GC I/7, later reinforced with 4 more, alongside a larger number of D520's. The only conclusive air combats by Moranes mentioned in that book are damage to a recon Hurricane June 7, one Morane downed by defensive fire from a Blenheim June 14, one Blenheim downed by Moranes July 4, one Wellington crashlanded after Morane night interception July 7. The conclusive fighter v. fighter actions in Syria all involved D.520's: among fighters D.520's downed 2 Tomahawks, 4 Hurricanes and 3 Fulmars for the loss of 3 to Tomahawks, 2 to Hurricanes and 4 to Gladiators. Those two campaigns Per "Dust Clouds over the Middle East" by Shores.

The other combat episode of Vichy Ms406's was in the Thai-French war of 1940-41. Around 20 Ms406's were the total French fighter strength in Indochina, against a larger but mainly biplane equipped Thai fighter force. They scored few victories confirmed by the Thai's though suffered no outright losses themsevles. Victories confirmed by the Thai's were 1 Mitubishi Ki-30 light bomber, and one Thai Hawk 75N (fixed undercarriage, 23mm podded cannon) crashlanded. One Morane landed on fire after combat with Hawk 75N's but was not counted lost by the French. Some or all the Moranes were missing their 20mm cannon though. In early 1942, after the French were forced to agree to Japanese bases in Indochina, Japanese Army Type 97 Fighters attacked Moranes once, mistaking them for AVG P-40's and shooting down 2. Per "l'Aviation Vichy au Combat" T.1 by Ehrengardt and Shores 

Joe


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## Elvis (Feb 24, 2009)

Clay_Allison said:


> ...and the sad stupid-looking P-26 Peashooter.


Saddest part of all is that the plane was originally designed with a one-piece wing and retractable undercarriage.  
-----------------------------------------------------

Rosseau,

I don't know about the other planes, but it seems the D.520 had its oil cooler moved to a separate "cowling" that was located under the fuselage, sort of like a Spitfire or a P-51.








Elvis


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## Twodeaddogs (Oct 21, 2009)

You'd wonder how much influence the D520 had on Soviet types.
regards
TDD


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## VG-33 (Oct 22, 2009)

Milos Sijacki said:


> Nice pics. Agree with You guys, OIL COOLER.
> 
> As long as we are talking about this plane, can someone tell me what was its combat history and what was it like in combat?
> 
> Cheers



Since i didn't found them in this thread, i venture to give you the right numbers from the SHAD,_ Armée de l'air_ archive's center.

1081 MS 406 produced, some later modified to MS 410 standards.

572 were on line on late august 1939, in 12 distinct fighter air groups.

Having a constant-speed propeller, pilot and fuel tank protection, it performed well during the "fonny war" against 109D, but was soon overclassed by the E model.

For this reason it was intended to be replaced by more modern fighters like the D-520, but due to huge delays in the replacement programm, only 6 groups began transformation in may 1940. 6 other planes fought on this plane until the end.

MS-406's were credited with 191 confirmed and 89 unconfirmed kills. 150 were lost due to battle damages before Battle of France begun to look like Barbarossa and 300 other MS-406 were abandonned or lost on the airfields during the retreat.

By general opinion was an easy, nimble and pleasant plane to fly, but was suffering from some technical troubles, and was outperformed by the 109 E. Nevertheless the improved MS-410 model was able to gain extra 25-35 km/h due to improved aerodynamics and new 910 hp Y-45 engine, and some other 15-20 km/h only by using propulsive exhaust pipes. In that form it was not inferior to the serial D-520.

Regards


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## vanir (Oct 22, 2009)

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. 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.

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.

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.

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.
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.

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.


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## Altea (Oct 23, 2009)

Hello Vanir,

I have to desagree on some points.




vanir said:


> 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


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## Altea (Oct 23, 2009)

Twodeaddogs said:


> You'd wonder how much influence the D520 had on Soviet types.
> regards
> TDD



And BTW, You'd not wonder how much influence had I-17on French (and other) types








TsKB-19


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## Vincenzo (Oct 23, 2009)

Altea are you sure that nominal it's same of max continous ?


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## vanir (Oct 23, 2009)

The ratings Altea gave are for the max climb rating at 2600rpm, essentially in this case it is the maximum continuous engine speed with the maximum boost allowed. You could raise engine speed safely to 2800-3000rpm but only for a very short period, this would provide higher outputs, but it would be called a war emergency rating. True enough there is no overboost per se, but an extra 2-400rpm adds horsepower in the torque x engine speed equation from which horsepower is calculated, simply raising rpm increases horsepower if manifold pressure is maintained. Maximum boost is effectively overboost on Yaks anyway because the listed maximum boost pushes the handle just past its gatestop (ie. it goes a little further forward than the maximum rpm setting for the prop pitch where for normal engine settings the two are aligned together).

I think you'll find also the Soviet octane rating will vary by calculation, I was using motor method, which minimalises it. Your figure will be an average of motor method and rated octane number. You get the same thing with British fuels, their 100 octane is actually 130 RON. So compared to "Soviet 95 octane," British 100 octane fuel is 115 octane. In addition, in any case fuel qualities vary by where it was mined and the refining processes and additives used. For this reason fuel octanes compare poorly between varied sources, German 96 octane (also using the motor method) is equivalent to 100/130 early in the war and 100/150 late in the war (Crumpp who built the Fw190A "White 1" told me this himself as he had to research a great deal about wartime fuels for his rebuilt BMW801 motor). British 87 octane was a typical prewar aviation fuel, used on most of their fighters and good for +6lbs on a Merlin engine. Upon the British adoption of 100 octane aviation fuel for fighters the Merlins were recalibrated for +12lbs. The +12lbs of Hurricane lend lease deliveries could not be used with Soviet fighter aviation fuel in 1941 and these engines had to be derated to no more than +6lbs. This is the reason for my likening of the Soviet fuel quality as (equivalent to) 87 octane British aviation fuel. American 91 octane fuel is the same as British 87 octane, again good for only +6lbs on a Merlin (or +8lbs or 47" Hg on an Allison). There is no doubt given the VK-107 and M82FN development during 1943 that Soviet fuel quality had improved, not for the least reason being the lend lease LF MkV Spits and Airacobras received did not have to be derated for the previous demonstrably poor Soviet fuel quality of 1941.

All I can say is not everything may be recorded for prosperity, but are still indicated by circumstance and physical example, by simple engineering realities. Many, if not most, if not all VVS a/c from 1943 could not possibly be run on the fuel type for which the Hurricanes had to be derated to +6lbs, the Soviet fuel type available in 1941.

About the engine settings, this is exactly the same as the issue about the listed output of the F3R Allison in the P40E, 1150hp at 11000ft says the book but this is not the maximum output of the engine which was first cleared for 1480hp to ~7000ft by Allison Division during 1941 and then finally 1680hp to 5000ft. Maximum pressure altitude may be increased by ram effect.
Yet still engineering tables list 1150hp for the Allison at 3000-3200rpm. And what's more at 3200rpm using ram effect you can manage over 1700hp pretty surely, again if you use a war emergency setting. This is frequently not even listed in manufacturer specifications, who tend to offer only the International rating (maximum continuous power) or the maximum climb rating (military power). Some give maximum take off power.

The 1100hp rating for the M-105P is for 2600rpm (as mentioned above, max continuous engine speed with maximum boost). The motor can do 3000rpm (though it is not advised to exceed 2800rpm, which is the listed maximum engine speed). You do the math. Same argument for the other motors. Just to be clear for any translation difficulties for non-english native tongues, pretty much any engine of the type can be run at a continuous setting, or a medium period military setting for climbing regimes, or an all out war emergency setting which overheats the motor quickly. This is because aero engine settings were almost completely under the control of the pilot back then and he had far more control over the way the engine handled than what you get with a flight computer or automatic management system, control of the motor was very manual. This was the reason for operational procedures being a matter of manufacturer released guidelines, any pilot could if he wanted to exceed the factory rated specifications for operation of the engine, exceed its maximum safe engine speed, ask his mechanic to recalibrate the throttle to the boost regulator for a higher than maximum overboost. A pilot could always do these things, he was not supposed to but sometimes pilots found their own better than manufacturer settings during actual service, and the manufacturer revised their operating procedures to suit. This happened exactly with the F-series Allison for example. In any case pretty much any engine of this type can be run at a military, continuous or a war emergency setting, even if the manufacturer only lists output ratings for one of these engine settings. Did you know the DB601A has a war emergency rating which is also simply a raised engine speed, or that the output listed for the Merlin 45 in the MkV Spit is a war emergency rating which can only be maintained for 5min, it's more like 1150hp just like an Allison at the 30min military setting, and as mentioned the Allison's rating is for military power.

I'm still trying to find the Russian aviation website article I read about field recalibration for the PF boost, it was a TsAGI article, I'll link it when I do. The carburettor was rejetted to prevent predetonation (the mixture needed to be richened) but the new pistons came for the 115cm boost of the PF2 iirc. They used to be cast and they switched to alloy for the PF2.
The PF2 entered service with the Yak-9 and this motor is not interchangeable with the 105P, true enough different pistons and perhaps reduction gear I don't know. The PF though was just a boost recalibration and it was fuel quality associated, I remember this clearly. The article which described test flights by TsAGI of various production improvements clearly stated no modifications to the motor itself was made between 105P and PF motors, it made a point of it.
If you have links with better detail I'd appreciate it. I'm not that excited that I'm going to go buy some books though, this is just a web forum challenge. I'm already comfortable with much of my research thus far.


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## tomo pauk (Oct 23, 2009)

Great post(s), Vanir. I really enjoy reading them


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## Shortround6 (Oct 23, 2009)

Aviation fuels from WWII do not really compare to motor fuels of today.

Each countery may have had their own specifications that included not only octane rating (how ever a country decided to measure it) but octane ratings at lean and rich settings ( british were the FIRST to specify this) BTUs per pound, Reid vapor pressure ratings, percentage of of Aromatics permitted, evaporation rates, sulfer content, amount of gum, even the max and min amounts of dye.

Becasue of the different base stocks, gasoline of the same basic "octane rating" did perform differently. 

Specifications also changed from before the war to during the war to post war. Some fuel's specifications might not have changed while others did. Something else to watch for, at least in the case of the US, is that military fuel specifications did not always match commercial aviation fuel specs. By 1951 this even went to different allowable limits for the amount of lead per gallon for the two different 100/130 fuels.

As far as "over speeding" engines goes, this can be gotten away with while diving to some extent. Throttle is part closed and the propeller is actually driving the engine. THe partially shut throttle restricts the amount of intake air and so limits the amout of power the engine is producing. Over revving the engine under full throttle conditions is a bit riskier. 
On a gear driven supercharger there is no seperate control over over the supercharger speed. I have one source that says high gear on the M -105 engine was 10 to 1 so if the engine is turning 2600rpm the supercharger is turning 26,000rpm. inceasing the RPM by of the engine by 300 means the supercharger HAS TO increase speed by 3000rpm. since the pressure delivered by the supercharger is proportional to the square of the impeller tip speed we can see that,unless there are restictions in the intake and outtakes (ducting/manifolds) there is going to be a very large increase in airflow and power. This inceases the manifold pressure as the rpm goes up. 
Both the origianol Hispano and the Russian M-105 were rather large engines (displacement wise) on the order of 36 liters or so or just a bit under a Griffon. They had a longer stroke than a Griffon and yet weighed less than a Merlin or Allison. Given that rod bearing loads go up with the square of the speed and the light construction of these engines I am not sure I see much overrevving/overboosting of these engines. 
I am sure it was done on occasion but some of the WAR emergency power ratings were only approved after a test engine had gone 7 1/2 hours on test bench at that rating. THis is to allow for production variations between engines so that the WORST engine out of every 100 doesn't blow itself up in a matter of seconds when abused in this way. 

As an aside I believe it almost became a courtmartial offense for British mechanics to "modify" the boost setting controls on the Napair Sabre engine after more than a couple of engines were destroyed by mechanics who "knew better" than the factory engineers


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## Altea (Oct 25, 2009)

Vincenzo said:


> Altea are you sure that nominal it's same of max continous ?




From the *definition* itself, it is. Or should be...

But caution!!!

- It's just for French and by extension, Soviet rules and procedures. Elsewhere it's certainly different.
- Max continuous power for an engine, does not mean max continuous speed for a plane for a lot of reason, mainly coolant ones.
- There was a lot of possible arrangements on some concrete cases. For example the Shvetsov M-62 for Polikarpov fighters had no official time limit, but the same reucted M-62IR for civilian planes (Li-2, An-2) was limited for one hour in "nominal" flight. For that price the M 62IR had a TBO of 400 hours (1 000 hours ower days) instead of only 100-150 for the militar one (M 62).


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## Geedee (Oct 25, 2009)

Are these any help in identifying bits ?. Taken at Flying Legends at Duxford over the past few years, she is quite a nifty little performer in the air....(allthough they did have a few problems with the clockwork this year)


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## Colin1 (Oct 25, 2009)

Geedee said:


> Are these any help in identifying bits ?. Taken at Flying Legends at Duxford over the past few years, she is quite a nifty little performer in the air....(allthough they did have a few problems with the clockwork this year)


It's tiny
it makes a Bf109 look big


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## Juha (Oct 25, 2009)

Thanks Gary
really nice photos. Seems to me ex-Swiss D-3801 or -3802 because of it has a fixed radiator but only 2 wing guns but of course French had also MS 406/410 hybrids

Juha


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## vikingBerserker (Oct 25, 2009)

Great pics!


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## FLYBOYJ (Oct 25, 2009)




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## Altea (Oct 30, 2009)

> The ratings Altea gave are for the max climb rating at 2600rpm, essentially in this case it is the maximum continuous engine speed with the maximum boost allowed.



Altea perfectly knows what he gaves you; the max power available with Klimov 105P and PF’s. Whatever you use it for climbing or just flying at max speed horizontaly both at 2600rpm. Only propeller path is changing in this case. Exactly as with your car, if you’ve got one with a gear box..




> You could raise engine speed safely to 2800-3000rpm but only for a very short period, this would provide higher outputs, but it would be called a war emergency rating.



I don't know *what* engine could you raise at 2800-3000 rpm, but not the Hispano-Suiza and not the Klimov 105 as i previously said.
The facts are that your boost and fuel levers, fully open *on thrust* position, the engine will run at 2700 rpm only or 2550-2600 with the R-7 constant speed propeller regulator slightly reduced for climbing or new engine (less than 20 hours wear) limitations procedures.

So it’s why i said there were *no emergency rating *on Klimov 105PF. Even if pilots could cheat over the 105P at low level with 975 mm boost instead of the nominal 910 mm, it was not calculated and not garanteed for that. This possibility on the M-105PF/PF-2 did no longer existed: it had 1050mm boost at best!






> True enough there is no overboost per se, but an extra 2-400rpm adds horsepower in the torque x engine speed equation from which horsepower is calculated, simply raising rpm increases horsepower if manifold pressure is maintained.


I’m not sure of that. Have you got a torque/rpm curve? The M 105 torque is probably decreasing over 2600 rpm. Even the Klimov M-106P and M-106SK ran at 2600 rpm for its 1350 hp max power, but at higher boost. 

Do you understand how an engine work?
To make it run at 2-400 rpm more you need to inject more fuel, more air. It takes an other (bigger) supercharger, other (bigger) carburettor, injectors, valves, maybe other plugs and switch advance circuitry. Take over the R-7 path regulator an replace by an other one. Can you explain us how can you do that with a serial Klimov M-105P or PF? I don't know about a lot of concrete examples, just one with certainly non-serial engines.




> Maximum boost is effectively overboost on Yaks anyway because the listed maximum boost pushes the handle just past its gatestop (ie. it goes a little further forward than the maximum rpm setting for the prop pitch where for normal engine settings the two are aligned together).


No it’s impossible, see higher. You can't get forward physically as in your _before quoted _car in standard configuration. 



> I think you'll find also the Soviet octane rating will vary by calculation, I was using motor method, which minimalises it. Your figure will be an average of motor method and rated octane number. You get the etc.... German 96 octane (also using the motor method) is equivalent to 100/130 early in the war and 100/150 late in the war (Crumpp who built the Fw190A "White 1" told me this himself as he had to research a great deal about wartime fuels for his rebuilt BMW801 motor).



You have confused/mixed a lot of things having no relationships between them: MON, RON, Poor mixture, rich mixture, aviation fuel tests, supercharged tests... The soviet 95 octanes fuel had* exactly* the behavior of a 95% iso-octane and 5% heptane mixture fuel on soviet CFR.

It (the 4B-78 ) was obtained by adding 4 cm cub of TEL to a natural 78 octanes kg raffinated from Bakou fuel. You can try owerdays, it’s still making 95 octanes by the same method.

Yaks were not using it, only M-82F/FN. The 2B-78 to 3B-78 mixtures for Klimovs 103A, 105, 106. And some 3.5B-78 for the M-107.

The German C-3 fuel, quoted at 94 by the TsAGI, had *exactly *the behaviour of a 93% iso-octane and 7% heptane mixture, on soviet CFR tests, that was running faster AFAIK (1500 rpm) than the german synthetical one.
From russian source:

_И последне не надо думать. что даже в такой малости три единицы октанового числа советский бензин уступал немецкой "синтетике" - у нас и у немцев были разные способы измерения октанового показателя. Т.ч. наше "93" у немцев было бы "96"._




> British 87 octane was a typical prewar aviation fuel, used on most of their fighters and good for +6lbs on a Merlin engine. Upon the British adoption of 100 octane aviation fuel for fighters the Merlins were recalibrated for +12lbs. The +12lbs of Hurricane.... This is the reason for my likening of the Soviet fuel quality as (equivalent to) 87 octane British aviation fuel. American 91 octane fuel is the same as British 87 octane, again good for only +6lbs on a Merlin (or +8lbs or 47" Hg on an Allison).



To obtain classical pre-war 87 octane fuel, soviets could use either:

- 3B-70 mixture
- 1.5B-74 one
- 1B-78 as well

Probably British had not produced a special supercharger for soviet 1941's standard 91-95 graded fuels that could range from 8,4712 to 10,8613 lbs rates.
Moreover, soviets had a lot of B-70 fuel basis to spend, that could not be used on very last engines.

BTW the rumanian petrol used by germans could naturally gave a 74 octanes mixtures basis at best, and some rare parts at 76. Germans were not using_ Eugène Houdry’s cracking methods_, AFAIK. But soviets with american help, did. In 1943 they were building 6 such a reffineries under licence. So late in the war they had 95 (soviet number) basis fuels that could provide from 96 (1B-95) to 115 (4B-95) octane number fuels.






> There is no doubt given the VK-107 and M82FN development during 1943 that Soviet fuel quality had improved, not for the least reason being the lend lease LF MkV Spits and Airacobras received did not have to be derated for the previous demonstrably poor Soviet fuel quality of 1941.



In 1942-1943 soviet fuel qulity had failed, because of , grozny , majkop production 78 basis reduction. Spits and Airacobras were simply using LL fuel supplys, if they were not derated.






> All I can say is not everything may be recorded for prosperity, but are still indicated by circumstance and physical example, by simple engineering realities. Many, if not most, if not all VVS a/c from 1943 could not possibly be run on the fuel type for which the Hurricanes had to be derated to +6lbs, the Soviet fuel type available in 1941.



It’s just your own supposals and extrapolations, BTW all false in our particular case....



> About the engine settings, this is exactly the same as the issue about the listed output of the F3R Allison in the P40E, 1150hp at etc....rating (military power). Some give maximum take off power.



On Allisons, maybe...I don't know.



> The 1100hp rating for the M-105P is for 2600rpm (as mentioned above, max continuous engine speed with maximum boost). The motor can do 3000rpm (though it is not advised to exceed 2800rpm, which is the listed maximum engine speed).


On Klimovs, no! There we strictly no device or features on that engine, that could allow to do better than factory-rated power! Except heavy modifications from factory, certainly not in front-line units!





> You do the math. Same argument for the other motors. Just to be clear for any translation difficulties for non-english native tongues, pretty much any engine of the type can be run at a continuous setting, or a medium period military setting for climbing regimes, or an all out war emergency setting which overheats the motor quickly.


Might be for some engines, certainly not for any of them. I don't understant your obstination to establish some parallels, that in fact never existed, from a country to another rules and procedures.




> This is because aero engine settings were almost .... Did you know the DB601A has a war emergency rating which is also simply a raised engine speed, or that the output listed for the Merlin 45 in the MkV Spit is a war emergency rating which can only be maintained for 5min, it's more like 1150hp just like an Allison at the 30min military setting, and as mentioned the Allison's rating is for military power.




I know, but there’s no analogy for that with french Hispano-Suiza or soviet-Klimov engines, except experimental ones in design bureau’s benchtests. This is a *cultural exception*.



> I'm still trying to find the Russian aviation website article I read about field recalibration for the PF boost, it was a TsAGI article, I'll link it when I do. The carburettor was rejetted to prevent predetonation (the mixture needed to be richened) but the new pistons came for the 115cm boost of the PF2 iirc. They used to be cast and they switched to alloy for the PF2.



I have already send you the values from the _TsAGI editions _book, Samoletostroenie.



> The PF2 entered service with the Yak-9 and this motor is not interchangeable with the 105P, true enough different pistons and perhaps reduction gear I don't know. The PF though was just a boost recalibration and it was fuel quality associated, I remember this clearly. The article which described test flights by TsAGI of various production improvements clearly stated no modifications to the motor itself was made between 105P and PF motors, it made a point of it.
> If you have links with better detail I'd appreciate it. I'm not that excited that I'm going to go buy some books though, this is just a web forum challenge. I'm already comfortable with much of my research thus far.



The PF-2 entered service with the Yak-3 in 1944. The PF with Yak-1 in mid-1942.


You can read pilots manual for the LaGG-3 both with 105PA and 105PF engines on:

??????????

Regards


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## Altea (Nov 4, 2009)

The M-105 af full power, both R-7 regulator and boost lever fully open: 1050mm boost and 2600-2700 rpm for the 105PF







or at soviet instruction film at 4.,19 min


_View: https://www.youtube.com/watch?v=2OZ3jgWGsoQ_


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## Shortround6 (Nov 4, 2009)

Even the Allsion wasn't that tolerant of over revving.

Froma training manual on the P-40, ANY over revving past 3120 rpm was to reported and written up so that appropriate inspections and maintence could be perormed as even a few seconds at that speed could cause bearing trouble on later flights.


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## waroff (Dec 6, 2009)

VG-33 said:


> Having a constant-speed propeller, pilot and fuel tank protection, it performed well during the "fonny war" against 109D, but was soon overclassed by the E model.



Propeller are not constant speed propeller.
- Chauviere propeller série 351, manual control, two pitch(pneumatic) 
- Ratier propeller série 1495, manual control, two pitch(electric). 
It's possible to obtain any position between low pitch and high pitch but it's not recommended by Morane Saulnier.

The only protection is an armour plate behind the head of pilot.


I hope you scuse me my very bad langage....

under the caracteristic of engine Hispano Suiza 12Y and curve












I sell a handbook of maintenance and repair of Morane Saulnier 406 , it's an original handbook (1939)
"notice d'entretien et de réparation de l'avion Morane Saulnier 406C1, 112 pages 66 planches dépliantes - 500€


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## Juha (Dec 6, 2009)

Hello waroff
the lower fuel tank in MS 406 was rubber coated and some of the 406s of Finnish AF had CS propeller.

and thanks for the graphs.

Juha


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## waroff (Dec 6, 2009)

Juha said:


> Hello waroff
> the lower fuel tank in MS 406 was rubber coated and some of the 406s of Finnish AF had CS propeller.
> 
> and thanks for the graphs.
> ...



Early MS 406 hav'nt self sealant tank. 
Perhaps latest MS 406, and 410, 412, morko morane.
for CS propeller, engine is not HS12Y and propeller are not Chauviere or Ratier 
MS 406 fench Armée de l'Air of Bataille de France and MS406 Finnish Air Force are very different! 
their aspect are similar but they are different.


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## Juha (Dec 6, 2009)

Hello waroff
According to part and equipment list dated 15 Jan 41, in all Finnish MS 406s the lower, 325l, fuel tank was rubber coated, and at that time we had only those MS406s we had got during the Winter War (30 Nov 39 – 13 March 40). Of course it is possible that Finns coated them between the end of the Winter War and the beginning of 1941. The Finnish AF 406s/410s had Chauviére 351, the most common, Hispano-Suiza 10B, Ratier 1607 or Soviet Hamilton Standard copy propeller. We also tested Swiss Escher Wyss propeller.

Juha


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## waroff (Dec 7, 2009)

Hello Juha,
thank's for your information.
Chauvière propeller serie 351 can't be use as CS propeller.
Ratier 1607 had control auto (CS), or manual. 
Ratier 1495 only manual control.
After 40, I dont know... 

Waroff


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## Juha (Dec 7, 2009)

Hello Waroff
yes when I wrote that some Finnish AF 406s/410s had CS propeller I meant those with Ratier 1607 or Escher Wyss.I'd check the Soviet Hamilton Standard copy from my SB material, it probably wasn't CS, but today I don't have time.

The coating of the lower fuel tank is not mentioned among the modifications made by Finns in Raunio's book on Finnish AF fighters. When I have time I'll check what I have on French 406s/410s. But Finns fitted back armour.

Juha


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## waroff (Dec 18, 2009)

Hello,
some picture of MS 405 N°9































model kit Azur 1/32


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## vikingBerserker (Dec 18, 2009)

Very nice.


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## DFM+BB (Dec 6, 2011)

Hello Guys !

As you are talking about MS406 Propeller.
One of my friend is asking me a question and I can't reply with assurance on this.

Lets say we found an Ms406 Hsipano Suiza engine somewhere in France and with this engine comes a propeller I can't identify seriously because it is written "Hamilton".
Can anybody confirm me if Ms 406 were fitted with Hamilton copy of any french propeller ??? I am absolutely lost on this.

thanks guys


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## Wurger (Dec 7, 2011)

As memo serves the plane could be equipped with three types of a propeller. Chauviere 351M of 3 m in diameter, Hispano-Suiza 270 and Ratier 1607, both of 3,1 m in diameter. The Hispano-Suiza made propellers on Hamilton licence. So it would be possible the one you found , was of a Hamilton Standard Hydromatic, especially , these props were available since 1937r. Of course we are talking about these three-blade props.


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## Siegfried (Dec 8, 2011)

Not a bad aircraft, by the time the war ended the Swiss had developed them into a 680km/h 422mph 1500hp fuel injected machine that was as fast as any Merlin Spitifre.

Apart from inadquet airframe production the French did lag somewhat in engine output leaving their fighters a few hundred hp down on the Me 109. They had improved engines on the Bench some very competitive eg the HS-12Z and the HS-12Y had plently of room to move in it.


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## Juha (Dec 9, 2011)

Now the first flight of the one and only D.3803 proto was May 47, not exactly during the WW2. And according to Peter Gunti’s article in AE 47, its max speed was 664km/h. Anyway both Saurer engines (YS-2 used in D-3802 and YS-3 used in D-3803) fell critically short in terms of reliability and performance. But even with its problems D-3802 and D-3802A had fairly good performance, they were based on MS 450 prototype, which first flew in 1939 in France. The first proto of D-3802 first flew on 29 Sept 44, production of 3802/3802A incl 3 protos and 10 pre-series planes, max speed 625km/h (390mph), climb 14.2m/s (46.5ft/sec) range 1200km (650nm). They were powered by Saurer YS-2 engines, V-12 engine which produced 1245hp and could be forced to an output of 1400hp for a limited duration.

Juha


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## Siegfried (Dec 9, 2011)

The Saurer engines were essentially based around the Hispano-Suiza engines with fuel injection as I understand it. Either way the engine and airframe looks like it could stand the test of time better than the Hurricane and P-40


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## Juha (Dec 9, 2011)

I might agree with Hurricane, but D-3802 was somewhat different looking animal than MS 406, British might well have got more out of Hurri if it had been the only plane to develop, but Hawker had Typhoon/Tempest line and RAF had also Spit, so there was no need to put much effort on Hurri. But clearly 3802/3803 and the Finnish Mörkö-Morane showed that 406 had still some development potential left. Mörkö still had the very nice handling qualities of 406 but was still slow, in reality max speed varied between 490 - 510km/h, depending on which plane was flown. So not much for mid 44 plane.

P-40Q might well have been a better plane than D-3802A

Juha


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## Shortround6 (Dec 9, 2011)

Siegfried said:


> The Saurer engines were essentially based around the Hispano-Suiza engines with fuel injection as I understand it. Either way the engine and airframe looks like it could stand the test of time better than the Hurricane and P-40



based rather loosely. They used 4 valve heads like the Hispano Z series engines and were about 100lbs heavier (1510lbs for the -2) than a Spanish Z and 140lbs heavier than a post war French Z .


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## tomo pauk (Dec 10, 2011)

Siegfried said:


> The Saurer engines were essentially based around the Hispano-Suiza engines with fuel injection as I understand it. Either way the engine and airframe looks like it could stand the test of time better than the Hurricane and P-40



Neither Hurricane nor P-40 received any substantial modification after 1941, while their basic engines were standing the test of time in exemplary fashion.


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## DFM+BB (Dec 11, 2011)

Thank you wurger !
Any picture of this HS-Hamilton prop ?


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## Wurger (Dec 11, 2011)

Nope...I have to check my references.


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## elbmc1969 (Feb 23, 2019)

Wurger said:


> As memo serves the plane could be equipped with three types of a propeller. Chauviere 351M of 3 m in diameter, Hispano-Suiza 270 and Ratier 1607, both of 3,1 m in diameter. The Hispano-Suiza made propellers on Hamilton licence. So it would be possible the one you found , was of a Hamilton Standard Hydromatic, especially , these props were available since 1937r. Of course we are talking about these three-blade props.



All three of these were 2-pitch, manually controlled props?

Were the French a little ahead of the British in getting 3-blade, 2-pitch props into service? I think the Brits still had some 2-blade fixed props in service during the May-June 1940 campaign.

What about the timing of the the Germans deploying advanced props, especially on the 109?


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## elbmc1969 (Feb 25, 2019)

Colin1 said:


> despite the presence of the 20mm cannon was weakly armed.


Simply not true compared to its contemporaries in the May-June campaign. It was facing Bf109E-3s and -4s, which had two MG-17s in the nose (synchronized) and two MG-FFs in the wings. Importantly, these were *not* MG-FF/Ms, so no Minengeschoss. That makes a huge difference in destructiveness. The H.S.404 (and even the HS-9 in the early production M.S.406s) had a much higher rate of fire and muzzle velocity than the MG-FF, which meant that it hit much harder. The French 20mm cannons and the MG-FF were all drum-fed with 60 rounds (often reduced to 55 rounds in service). The MG-FFs had more total firing time, but that was because of their low rate of fire, so it's not an advantage. Of course, the MG-FFs were also slightly less efficient because they were in the wings and had to have their harmonization set, while the H.S.404 and HS-9 were firing through the propeller hub, the optimal location. The only advantage that the 109 had was with the machine guns, because the MG-17s were belt-fed, while the MAC-34s were hobbled by being drum-fed. This made no difference in firepower per second, but did mean that the MG-17s had vastly longer combat endurance. We know from experience that a pair of rifle-caliber MGs is ineffective as the armament of a WWII fighter, but they could be used for sighting in the MG-FFs and they were actually somewhat effective against the M.S.406 because it lacked pilot armor and effective fuel protection. Against other fighters and bombers, the MG-17s were much less effective.

The Williams-Gustin formula for the Spitfire and Hurricane gives effectively the same gunpower as for the MS406, although they have longer firing times available. However, the lack of harmonization during the May-June campaign would significantly reduce their effectiveness. Again, if they were firing at an MS406 the .303 bullets would be more effective because of the lack of seat-back armor. Of course, they'd actually be firing at Bf109s, so that's not a real issue.

The D.520 was only available in limited numbers during the campaign, and its firepower only varied by the addition of two more wing-mounted MAC-34s, which was a trivial increase in gun power. Duration for the MAC-34s was significantly increased by changing to the new belt-fed version (675 rpg vs. 300) and with four guns (albeit wing-mounted), it actually had a vague chance of shooting down a German fighter, or even a bomber with very careful shooting (deflection shooting would be best, but I'm not sure French pilots trained for it much--doctrine seems to have been the low overtake would force shots from 6 o'clock).

The Bloch 150-155 were much more heavily armed with their pair of HS-404, although they were in the wings and limited by ammo drums. With the full four belt-fed MAC-34s, the Bloch had decent combat endurance with the rifle-caliber MGs, and the same MG-only gun power as the D.520. The Blochs were exceptionally heavily-armed for the period. While their performance wasn't up to snuff, they were very well-suited for knocking down bombers.

To sum up, the M.S.406 had essentially the same hitting power as its contemporaries. The exception of the Bloch 15x was an outlier among all of the single-engined fighters; we're ignoring the twin-engined fighters because all of the single-seat fighters would compare in the same way and the twins have their own set of advantages and disadvantages.


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## yulzari (Feb 25, 2019)

There were also Blenheims, Gladiators and Swordfish involved with Swordfish sinking a French destroyer in Syria. 

In Madagascar there were MS406 opposing Martlets in 1941


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## Shortround6 (Feb 25, 2019)

elbmc1969 said:


> The H.S.404 (and even the HS-9 in the early production M.S.406s) had a much higher rate of fire and muzzle velocity than the MG-FF, which meant that it hit much harder.



There seems to be some dispute about this, The HS 9 may have had a cycle rate of around 400rpm, (360-420rpm?) which is slower than an MG/FF. 
Which does make a bit of sense as the HS 9 is a licenced Oerlikon FFS cannon (modified from the HS 7) . Part of this depends on when the licence was taken out and what stage the basic gun was at at the time. 
Oerlikon was selling (licencing) three guns during the 20s, the FF using a 72mm long case, the FFL using a 100mm long case and the RRS using the 110mm long case. Not all licensees kept the exact case dimensions of the parent cannon but the longer cartridges need a longer bolt travel and will usually fire slower at a given stage of development, Unfortuanly for the french this means that most people were using these cannon several years after they were. 

Marc Birkigt was not happy with the HS 9 and designed his own cannon. Here things get a bit more uncertain as an early specification for the HS 404 shows a cycle rate of 400rpm and a MV of 830 meters a second, however this is several years before the gun goes into service. The British gun (which was the MK II) cycled at around 600rpm and had a velocity of 878m/s
What version the French were using (or when they changed over) is certainly subject to question and not helped by the fact Mr Williams book says 700rpm for the French gun. Misprint or?????


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## Greyman (Feb 25, 2019)

The French HS 404 guns had a rate of fire of 700 rpm. During tests in 1939 it was shown that reliability and life of the gun was greatly improved if it was toned down to 600 rpm - and the lower rate of fire was specified for later versions of the gun (which turned out to be just the British variety).


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## Shortround6 (Feb 25, 2019)

Greyman said:


> During tests in 1939 it was shown that *reliability* and life of the gun was *greatly improved*




Hmmmm, gun stops working 1/2 way through 60 round drum? that sure sounds like an improvement in firepower over the german MG/FF 

Given the troubles that many guns had meeting their specified number for the first few years of the war (and the American .50 was among the leaders in troubles in the first few years despite it's later reputation) some of these advertising brochure rates of fire need a bit of salt to go with them.


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## elbmc1969 (Feb 25, 2019)

Shortround6 said:


> an early specification for the HS 404 shows a cycle rate of 400rpm and a MV of 830 meters a second, however this is several years before the gun goes into service. The British gun (which was the MK II) cycled at around 600rpm and had a velocity of 878m/s
> What version the French were using (or when they changed over) is certainly subject to question and not helped by the fact Mr Williams book says 700rpm for the French gun. Misprint or?????


Contemporary sources I've seen show 570 and 700 rpm. Not sure if this was defensive guns vs. fixed, or just original max vs. limiting for reliability and barrel life. 700 rpm is a real number, however.


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## elbmc1969 (Feb 25, 2019)

Shortround6 said:


> The HS 9 may have had a cycle rate of around 400rpm, (360-420rpm?) which is slower than an MG/FF.
> Which does make a bit of sense as the HS 9 is a licenced Oerlikon FFS cannon (modified from the HS 7) . Part of this depends on when the licence was taken out and what stage the basic gun was at at the time.


The first 1/3 of the M.S.406 production run mounted the HS-9. Because the HS-404 essentially dropped in I'm place of the HS-9, the 406s were actively upgraded with the HS-404, which seems to have been one of few pieces of equipment that ran ahead of airframe production. This was also one of the few upgrades to the M.S.406 that could be accomplished with minimal fuss.

By the May-June campaign, the HS-9 wasn't a significant factor.


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## elbmc1969 (Feb 25, 2019)

elbmc1969 said:


> All three of these were 2-pitch, manually controlled props?


Came across this in a SHDDA listing: Moteurs Hispano-Suiza 12Y, réducteur pour hélice à pas constants et circulation d’huile : plans.
Dated 1937-1938.

So, a constant speed prop was well under development before 1940 for the 12Y (not just the 12Z for the D.520). Don't know if it couldn't be retrofitted to the M.S.406 or if prop production was just running too far behind to devote any to the 406s.

MINISTERE DE LA DEFENSE SERVICE HISTORIQUE DE LA DEFENSE Centre des archives de l’armement et du personnel civil SERIE 2 K 3 1085 2K3 1 à 9 Archives de l’établissement d’essais de moteurs du service technique de l’aéronautique d’Orléans-Bricy 1926-1949 Inventaire n° 1085 2K3 Version de novembre 2015 Par Sylvain Lebreton Chef du département des archives de l’armement Châtellerault 2015

Document 1085 2K3 3

[Yeah, another dumb error with me talking about the 12Z ...]


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## Greyman (Feb 25, 2019)

For what it's worth, recorded rates of fire from Hispano guns in firing trials. Various Spitfires, various front mounting units.

Recorded rates of fire of Hispano Mk.II cannon:
600, 610, 625, 535, 595, 665, 594, 530, 660, 660, 530

I got a chuckle when I did the math: average rate of fire? 600.36 rounds per minute

Recorded rates of fire of Hispano M.2 cannon:
660 & 680

Recorded rates of fire of Hispano Mk.V cannon:
720, 750, 725, 750, 750, 690, 730, 765

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## elbmc1969 (Feb 26, 2019)

Greyman said:


> For what it's worth, recorded rates of fire from Hispano guns in firing trials. Various Spitfires, various front mounting units.


Regardless, the D.520 and VG-33 were not significantly better armed than the M.S.406. The Germans, of course, abandoned the twin MG-FF/Ms despite the destructive Minengeschoss shells and went with a hub-mounted MG151/20 (after briefly using the MG-FF/M in the propeller hub. This certainly indicates that the M.S.406's armament wasn't far off the mark. Certainly, it would have been outclassed by early 1941, but it was fine for the May-June campaign.


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## tomo pauk (Feb 26, 2019)

elbmc1969 said:


> Regardless, the D.520 and VG-33 were not significantly better armed than the M.S.406. The Germans, of course, abandoned the twin MG-FF/Ms despite the destructive Minengeschoss shells and went with a hub-mounted MG151/20 (after briefly using the MG-FF/M in the propeller hub. This certainly indicates that the M.S.406's armament wasn't far off the mark. Certainly, it would have been outclassed by early 1941, but it was fine for the May-June campaign.



Replacement of two MG FFMs by single MG 151/20 was not universally welcomed in Luftwaffe. Even though MG 151/20 was a very good wepon. Galland insisted and got two MG FFMs for his '109F special', as well as replacement of two MG 17s with two MG 131s.
We can also recall that MG FFM was used aboard Fw 190s by some two years.
But, at any rate, having a working cannon in a fighter in 1940 was certainly a plus; problem the MS.406 had was low performance, rather than a perceived lack of firepower.


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## Shortround6 (Feb 26, 2019)

The MG 151 cannon in the 109's propeller, after they finally (after several years) got the MG/FF to work in that position with an acceptable level of reliability, had several advantages over the MG/FF. 
1. much greater ammo capacity. 
2. higher rate of fire, around 700rom vs 500rpm (at best?)
3, higher velocity making deflection shooting easier. (the MG 151/15 was the champ but the MG 151/20 fired shells (non mine) 18% faster than the MG/FF with a corresponding reduction in flight time). 

As far as the Ms 406 argument goes. 60 rounds is 60 rounds. you have 60 rounds of 20mm ammo. the 109E-3 had 110-120 rounds depending on how full the drums were even if they weren't mine shells. 
1 or 1.5 seconds extra firing time for the slower firing cannon isn't that big a deal. How many pilots succeeded using their last 1-2 seconds of ammo? Not saying that a few didn't get a kill that way but it wasn't a huge factor.


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## elbmc1969 (Feb 26, 2019)

To be clear, I was only responding to the assertion that the M.S.406 was underarmed. The accusation certainly doesn't make sense in comparison to the D.520, which only added two more MAC-34s.



tomo pauk said:


> We can also recall that MG FFM was used aboard Fw 190s by some two years.


For space reasons, not because it was a desirable weapon. Mixing the ballistics of three weapons was really, really sub-optimal.

In any case, a side issue, and you're definitely right that having a cannon was better than not.



Shortround6 said:


> The MG 151 cannon in the 109's propeller, after they finally (after several years) got the MG/FF to work in that position with an acceptable level of reliability, had several advantages over the MG/FF.
> 1. much greater ammo capacity.
> 2. higher rate of fire, around 700rom vs 500rpm (at best?)
> 3, higher velocity making deflection shooting easier. (the MG 151/15 was the champ but the MG 151/20 fired shells (non mine) 18% faster than the MG/FF with a corresponding reduction in flight time).


Yep, yep, yep, and yep. No arguments there, even if it doesn't directly relate to the question of the Bf109E-3 and early -4's armament compared to the M.S.406.

I suspect that getting rid of the wing guns improved roll rate, along with other things. And dang, the increase in ammo capacity made up for everything.



Shortround6 said:


> As far as the Ms 406 argument goes. 60 rounds is 60 rounds. you have 60 rounds of 20mm ammo. the 109E-3 had 110-120 rounds depending on how full the drums were even if they weren't mine shells.
> 1 or 1.5 seconds extra firing time for the slower firing cannon isn't that big a deal. How many pilots succeeded using their last 1-2 seconds of ammo? Not saying that a few didn't get a kill that way but it wasn't a huge factor.


Particularly the fire before that last burst is less effective than the competition. That said, at least if you can sight in with the MGs, you can get a lot more out of that last burst than you otherwise would.

From Lundstrom's The First Team, the Wildcat pilots seem to have done a lot of damage with their final bursts, often because they were finishing off damaged aircraft or were firing from shorter range than before. There were probably other factors. OTOH, if you can just hit and kill the target with your second burst, you're better off all around.

Incidentally, I see that the D.520 had switches that were apparently selectors for the cannon and each wing's machine guns. (The could be for charging, I suppose.) Anyone know if this is correct? Did the M.S.406 have selectors?


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## tomo pauk (Feb 26, 2019)

elbmc1969 said:


> For space reasons, not because it was a desirable weapon. Mixing the ballistics of three weapons was really, really sub-optimal.
> 
> In any case, a side issue, and you're definitely right that having a cannon was better than not.



I agree that mixing 3 wepons with different ballistics was sub optimal, and certainly having extra firepower is a good thing (provided one does not over-do it). OTOH, ballistics of MG 17 and MG FFM were not that different.
Space reasons did not prevented instalaltion of MG 151/20 inn outer wing position (they were installed there from Fw 190A-6 and on in factory, even the MK 108 was), but probably it was the case of not having enough of MG 151s.


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## Shortround6 (Feb 26, 2019)

I am afraid the whole using machine guns to sight in for the cannon thing is something of a myth.
Not saying it wasn't put forth as a technique at the time or tried, just that it isn't going to work very well. 
You have the different ballistics thing going on, that is different times of flight to the same distance needing different amounts of lead. You also have the problem of any tracer or impact system, it tells you where you should have been aiming around a 1/2 second ago or so (depending on range) .


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## elbmc1969 (Feb 28, 2019)

tomo pauk said:


> I agree that mixing 3 wepons with different ballistics was sub optimal, and certainly having extra firepower is a good thing (provided one does not over-do it). OTOH, ballistics of MG 17 and MG FFM were not that different.


Not talking about that so much as the ballistic differences between the MG FFM and the MG 151/20.


tomo pauk said:


> Space reasons did not prevented instalaltion of MG 151/20 inn outer wing position (they were installed there from Fw 190A-6 and on in factory, even the MK 108 was), but probably it was the case of not having enough of MG 151s.


Sure, but engineering solutions evolve over time, and what people are willing to put up with evolves over time. The MG 151/20s in the outer wings just took more engineering effort, and the engineers may not have been able to come up with an acceptable solution in the time available. They had to get the 190 into flight testing and then into production. Then you go back an improve things after the initial release to production. I've seen this with all sorts of engineering.


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## tomo pauk (Feb 28, 2019)

elbmc1969 said:


> Not talking about that so much as the ballistic differences between the MG FFM and the MG 151/20.



Ballistic differences were similar when in is about MG 131 and MG 151/20, a set-up often found on German fighters. Or MK 108 vs. MG 151/20 or MG 131, again a frequent occurance.



> Sure, but engineering solutions evolve over time, and what people are willing to put up with evolves over time. The MG 151/20s in the outer wings just took more engineering effort, and the engineers may not have been able to come up with an acceptable solution in the time available. They had to get the 190 into flight testing and then into production. Then you go back an improve things after the initial release to production. I've seen this with all sorts of engineering.



The engineers were replacing one cannon with another, admitedly longer (that goes mostly into the air anyway) and heavier, and again with a bigger one (MK 108). They are not trying to stick a jet engine on it, or a swept wing (although there were proposals about those, too).


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## Shortround6 (Feb 28, 2019)

elbmc1969 said:


> Simply not true compared to its contemporaries in the May-June campaign. It was facing Bf109E-3s and -4s, which had two MG-17s in the nose (synchronized) and two MG-FFs in the wings. Importantly, these were *not* MG-FF/Ms, so no Minengeschoss. That makes a huge difference in destructiveness. The H.S.404 (and even the HS-9 in the early production M.S.406s) had a much higher rate of fire and muzzle velocity than the MG-FF, which meant that it hit much harder. The French 20mm cannons and the MG-FF were all drum-fed with 60 rounds (often reduced to 55 rounds in service). The MG-FFs had more total firing time, but that was because of their low rate of fire, so it's not an advantage



Unfortunately the German MG/FF was used for only a short time and tends to get overlooked or lumped in the MG/ FFM. The Mine shell seems to hog all the attention/glory. 

The MG/FF was supposed to use a 134 gram projectile (4-6 grams heavier than a Hispano Projectile) at 600M/S velocity. This is about 17-19 grams heavier than the non mine shells fired by the MG/FF and MG 151/20. It also had a slightly higher velocity but only about 15M/S worth compared to the MG/FFM. It does mean the old MG/FF cannon had about 20% more kinetic energy at the Muzzle than the MG/FFM firing non mine shells. 
Now a big difference could be that the old shells _may _have had up to 10 grams of HE per shell, there is no real reason to think they had much less as most other shells of their size/weight and type held about 10 grams. The lighter 115-117 gram shells used in the MG/FFM did hold much less HE, but mostly because they devoted a fair amount of internal space to the tracer element. I don't believe they ever made a mine shell (at least in 20mm ) with tracer. 
The MG/FF may have been fairly comparable to the Hispano as far as HE destructiveness goes on a shell for shell basis. The rate of fire was a nominal 520-540 rpm but actual rate of fire may have been a bit lower. At 500rpm a 55 round drum will last 6.6 seconds. A 700 rpm Hispano will go through 60 rounds in 5.4 seconds.
One could play the statistical game and say the Germans have 22% more firing time but in the real world 1 second isn't that big a deal, it certainly isn't enough for another firing pass for 99.99% of the pilots that flew in WW II.
How good (or bad) the fuses were on the French and German ammo at this time I have no idea. The British shortly after the Battle of France (or the BoB) had so much trouble with their 20mm HS shells exploding on impact (fuselage or wing skin) and not getting inside before detonating that they took to mixing in inert training projectiles (they called them ball rounds) in order to insure that some projectiles would get deep into an aircraft and cause damage there. Later they got improved fuses that detonated the shells several feet inside the aircraft.

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## Greyman (Feb 28, 2019)

Shortround6 said:


> How good (or bad) the fuses were on the French and German ammo at this time I have no idea. The British shortly after the Battle of France (or the BoB) had so much trouble with their 20mm HS shells exploding on impact (fuselage or wing skin) and not getting inside before detonating that they took to mixing in inert training projectiles (they called them ball rounds) in order to insure that some projectiles would get deep into an aircraft and cause damage there. Later they got improved fuses that detonated the shells several feet inside the aircraft.



The early British fuzes (No.252) followed the design of French fuzes very closely, so I imagine they suffered the same issue.

On testing captured examples, early German 20-mm fuzes were criticized by the British as being as bad as their own with respect to detonating too early. This was in 1940, I'm not sure how things progressed from there. I know for sure the Luftwaffe, like the British, updated their fuzes several times.


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## Shortround6 (Feb 28, 2019)

Thank you. Perhaps the fuses were intended to function on fabric covered airplanes (or on both types of skinning) as there were still considerable numbers of fabric covered (or partially) aircraft in the late 30s?


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## Greyman (Mar 1, 2019)

I haven't seen that specifically stated but I'd say it's a good bet. I've read evaluations of cannons as late as 1937 (25mm Hotchkiss) where the assessors made specific notes on how the rounds functioned on fabric.


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## ThomasP (Mar 18, 2019)

I once read a write-up on the HS404 in UK service in WWII. It was quite clear about the different ROF. The 650-660 rpm was when the gun was fed from a 60-round drum magazine. The 600 rpm and less was when when using a belt feed system. Even when using a servo powered feed assist mechanism the ROF dropped by 10%-20% depending on the weight of the belt and the ergonomics of the installation. The write-up also stated that the belt-fed installations in the P-38E had a similar reduction in ROF compared to the original drum-fed installation in the P-38 and the standard installations in the P-400 and P-39D-1.


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## Glider (Mar 18, 2019)

All I can add is that the manual for the RAF 20mm mk II quotes it as having a rate of fire of 570 - 620 rpm


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