French airforce from 1935 to 1940-41?
- Thread starter tomo pauk
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But was it a better plane even without the crashes.
Loire-Nieuport 161 - Wikipedia
Le Nieuport 161, formidable chasseur de 1936. (Clarifié le 30 / 09 / 2024 * *** *** ***)
( cick here to read this post in English ) Lorsque notre Armée de l'Air est entrée dans la guerre contre la Luftwaffe de Goering, en 1939,...
aviadrix-blogspot-com.translate.goog
Problem: the said "Drix" while well informed (he has data on French interbellum never seen anywhere on the web) is NOT objective - and tends to rants like Grandpa Simpson in a bad day.
To his credit, DMZ made his own research to counter-balance Drix "opinions rather than facts" attitude.
It seems the LN-161 was a better aircraft; crucially, another advantage was it could have been built much faster than the Morane (think Hurricane vs Spitfire; Supermarine had difficulties churning Spitfires fast enough, but Morane was 10 times worse).
A case could be make the LN-161 could have been an in-between MS-406 and D-520 at a crucial time: very much a french Hurricane.
The LN-161 was rejected OTL, first because it was rather unlucky with its crashes.
There might be darker (but unproven) reasons, related to Lockheed-like briberies by Morane Saulnier toward the military or 3rd Republic politicians. In late 30's France that kind of things happened... all too frequently.
The LN dive bombers were the closest thing from a Stuka France ever got.
Mind you, the Armée de l'Air started that program in 1937 only to dump it (and dive bombing) the next year, to the Aéronavale; and start the Breguet 690 series in its place.
The very Breguets that lost 8 out of 18 at their first raid against Panzers in Central Belgium on May 12, 1940.
Which brings the following points
- the Armée de l'Air never clearly defined how it intended to destroy panzers
- Dive bombing with LN ?
- No "Stuka blietzkrieg" tactics like the Germans
- Nope, Breguet 690 at tree tops... right into the thick of the flak
- final answer: surviving Breguets at 1000 to 2000 feet, semi-diving... but they had no bomb sights ! (facepalm).
On top of that, the few LN-401/411 dumped at the Navy were called to the rescue mid-May, along with the Vought V-156F "Wind indicator / Cheese cake"; five squadrons worth of dive bombers (three of Vought, two of LN) that were wiped out in three or four raids against bridges in northern France.
One squadron of Voughts was wiped out by a bombing of their hangar on Day 1
Second squadron was wiped out by flak, along LNs, on a couple of attacks on bridges
Third and last squadron was caught unescorted by 109Es and wiped out.
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A question about armament: one D.520 (No.49) was fitted with an engine-mounted 23mm cannon for tests against AFVs but was shot down on its first operational mission on 11 June 1940.
The cannon is usually assumed to be a Madsen (a 23mm version being tried by several air forces in the late 1930s) but that was no more powerful than the Hispano, so I suspect that the gun might have been the experimental - and very powerful - HS.407. Does anyone have any information about this?
The cannon is usually assumed to be a Madsen (a 23mm version being tried by several air forces in the late 1930s) but that was no more powerful than the Hispano, so I suspect that the gun might have been the experimental - and very powerful - HS.407. Does anyone have any information about this?
Never heard about this story.
This (glorious) website seemingly has serials of all D-520s, and mentions indeed that Number 49 was shot down that day, but no mention of a specific gun. Will browse further using the pilot name.
Same for this
francecrashes39-45.net
This (glorious) website seemingly has serials of all D-520s, and mentions indeed that Number 49 was shot down that day, but no mention of a specific gun. Will browse further using the pilot name.
Same for this
Recherche de France-Crashes 39-45
39-45 - Recensement de tous les avions français, anglais et americains tombés sur le territoire français pendant la deconde guerre mondiale.
I've found the sources for that claim (of D-520 number 49 with the HS.407) but no idea if the gun was still there when it was shot down in June.
As for the 20 mm gun, the Breguet 690 series had one in the nose, so it was certainly tested, including in combat. Loss rates however were atrocious.
78 Breguet 691 and 128 Breguet 693 were delivered before the capitulation. The 691s were good for nothing, and the 693s armed only two squadrons in May (I/54 and II/54) they were too few and took terrible losses.
As for the 20 mm gun, the Breguet 690 series had one in the nose, so it was certainly tested, including in combat. Loss rates however were atrocious.
78 Breguet 691 and 128 Breguet 693 were delivered before the capitulation. The 691s were good for nothing, and the 693s armed only two squadrons in May (I/54 and II/54) they were too few and took terrible losses.
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Charlesferdinand
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I'm not convinced that the run down of the French aviation industry in the aftermath of WW I was al that important. It certainly didn't help, but in that period it was actually illegal in Germany to make any kind of warplane. Yet in 1939, the Luftwaffe was doing just fine.
The most important point about the French bomber force of 1940 is that it didn't exist.
When war broke out in 1939 all Groupes de Bombardement in metropolitan France were still equipped with the various results of the BCR programme (Pz54, MB 200, MB210 F222 and Am 143). The new aircraft were only slowly coming on line in the spring of 1940. The Aéro Journal Hors Série Le bombardement français lists the following operational strength in April 1940: 6 Douglas DB7, 64 LeO 541 and 33 Martin 167. (The French airforce had more aircraft on hand, but this is the official strength given as fit for operations). Likewise the operational strength in May 40 was ridiculous:
Zone d'opérations aériennes nord had 22 LeO 541, 24 Am 143 and 2 Am354.
Zone d'opérations aériennes est had 19 Am 143, 6 F222 and 3 MB200
(this is only counting the Groupes de Bombardement, you'd have to add l'aviation d'assault)
To stem the tide, units that were still converting to new planes in the South of France or North Africa were hurriedly thrown into the battle. So you have aircrew and groundcrew that are unfamiliar with modern planes (remember, they are used to BCRs) operating from improvised bases with a chaotic logistic situation.
Regardless of what aircraft would be suitable, the first priority should have been to have modern aircraft operational at all.
The most important point about the French bomber force of 1940 is that it didn't exist.
When war broke out in 1939 all Groupes de Bombardement in metropolitan France were still equipped with the various results of the BCR programme (Pz54, MB 200, MB210 F222 and Am 143). The new aircraft were only slowly coming on line in the spring of 1940. The Aéro Journal Hors Série Le bombardement français lists the following operational strength in April 1940: 6 Douglas DB7, 64 LeO 541 and 33 Martin 167. (The French airforce had more aircraft on hand, but this is the official strength given as fit for operations). Likewise the operational strength in May 40 was ridiculous:
Zone d'opérations aériennes nord had 22 LeO 541, 24 Am 143 and 2 Am354.
Zone d'opérations aériennes est had 19 Am 143, 6 F222 and 3 MB200
(this is only counting the Groupes de Bombardement, you'd have to add l'aviation d'assault)
To stem the tide, units that were still converting to new planes in the South of France or North Africa were hurriedly thrown into the battle. So you have aircrew and groundcrew that are unfamiliar with modern planes (remember, they are used to BCRs) operating from improvised bases with a chaotic logistic situation.
Regardless of what aircraft would be suitable, the first priority should have been to have modern aircraft operational at all.
Good post. And you know why the French bomber command was in such poor shape ?
a) because fighters are defensive weapons
b) as such, they don't trigger the wrath of the LW on Paris and elsewhere
c) fighters are also cheaper and faster to produce than bombers.
Sooo, circa 1938-39, and because of all three reasons above, France prioritized fighters over bombers.
End results: 360 fighters by May 1940, most of them (unfortunately) MS-406
... and barely 27 modern bombers near the Ardennes: two groups of LeO-451 and two assault squadrons of Breguets.
Nothing else: the Amiots were scarce and incomplete; the (excellent) US bombers, DB-7 and Martin 167F, were either in Casablanca or far from the front or too few.
In passing, the more I read on Charles Huntziger, the more I hate the man.
en.wikipedia.org
He was kind of lucky to die in November 1941 when his aircraft, returning to Vichy, slammed in a mountain; because he was as much a traitor as Pétain, and as much a dumbarse without a brain as Gamelin.
Just like the 9-11 "truthers" that are looking for a conspiracy to reassure themselves explaining the 9-11 was an "inside job" (total bollocks) I've red that some people are so appalled by Huntziger mediocrity, they are convinced he was a traitor BEFORE May 1940, in a conspiracy with Pétain to trigger MAy 1940 disaster, and engineer Vichy !
Which is total bollocks, but speaks volume about how the 1940 defeat is apalling in retrospect.
People are looking for a conspiracy where there was just 100% dumbarsery, idiocy, complacency, and arrogance (to you, Huntziger and Gamelin. Daladier, too. And countless others).
a) because fighters are defensive weapons
b) as such, they don't trigger the wrath of the LW on Paris and elsewhere
c) fighters are also cheaper and faster to produce than bombers.
Sooo, circa 1938-39, and because of all three reasons above, France prioritized fighters over bombers.
End results: 360 fighters by May 1940, most of them (unfortunately) MS-406
... and barely 27 modern bombers near the Ardennes: two groups of LeO-451 and two assault squadrons of Breguets.
Nothing else: the Amiots were scarce and incomplete; the (excellent) US bombers, DB-7 and Martin 167F, were either in Casablanca or far from the front or too few.
In passing, the more I read on Charles Huntziger, the more I hate the man.
Charles Huntziger - Wikipedia
He was kind of lucky to die in November 1941 when his aircraft, returning to Vichy, slammed in a mountain; because he was as much a traitor as Pétain, and as much a dumbarse without a brain as Gamelin.
Just like the 9-11 "truthers" that are looking for a conspiracy to reassure themselves explaining the 9-11 was an "inside job" (total bollocks) I've red that some people are so appalled by Huntziger mediocrity, they are convinced he was a traitor BEFORE May 1940, in a conspiracy with Pétain to trigger MAy 1940 disaster, and engineer Vichy !
Which is total bollocks, but speaks volume about how the 1940 defeat is apalling in retrospect.
People are looking for a conspiracy where there was just 100% dumbarsery, idiocy, complacency, and arrogance (to you, Huntziger and Gamelin. Daladier, too. And countless others).
Folks, this is a must read. It is a collection of quotes (nowadays we would say "punchlines") by 1940's France politicians and military commanders.
leprintempstragique-wordpress-com.translate.goog
There are, in that document, some quotations that just leave one shaking his head in disbelief.
This document is, for me, like a cult movie, you know, like Ed Wood movies. I mean: the kind of B-movie which is so bad, it makes you laugh incontrollably.
Some of these punchlines are straight out of these movies.
https://en.wikipedia.org/wiki/OSS_117#Parodies
(René Coty ? a great leader and a visionary; history will forever remember him)
Check some quotes by Gamelin and Huntziger, and prepare to burst into laughter - or tears.
Those were the arrogant pricks that led my (unfortunate) country into battle in 1940.
Well "Battle" is too lenient a term "Agincourt 2.0" or "Crecy 2.0" or "carbon copy of 1870" would be more appropriate description.
Goddam Huntziger said, TWICE (because ONCE wouldn't be enough stupidity, you guess) in APRIL 1940 and on MAY 7, 1940
"Meh, the Germans will never attack in the Ardennes." What a visionnary !
Frack me, the French HQ in 1940 was exactly that: a bunch of Simpson males with the genetic deadly flaw.
View: https://www.youtube.com/watch?v=ilwUXv_Kq7A
Recueil de citations, 1939-1940.
Lénine aurait déclaré que « la citatiomanie est notre plus grande ennemie. » Même si cette phrase semble être plus vraisemblablement une citation apocryphe, il n’empêche…
leprintempstragique-wordpress-com.translate.goog
There are, in that document, some quotations that just leave one shaking his head in disbelief.
This document is, for me, like a cult movie, you know, like Ed Wood movies. I mean: the kind of B-movie which is so bad, it makes you laugh incontrollably.
Some of these punchlines are straight out of these movies.
https://en.wikipedia.org/wiki/OSS_117#Parodies
(René Coty ? a great leader and a visionary; history will forever remember him)
Check some quotes by Gamelin and Huntziger, and prepare to burst into laughter - or tears.
Those were the arrogant pricks that led my (unfortunate) country into battle in 1940.
Well "Battle" is too lenient a term "Agincourt 2.0" or "Crecy 2.0" or "carbon copy of 1870" would be more appropriate description.
Goddam Huntziger said, TWICE (because ONCE wouldn't be enough stupidity, you guess) in APRIL 1940 and on MAY 7, 1940
"Meh, the Germans will never attack in the Ardennes." What a visionnary !
Frack me, the French HQ in 1940 was exactly that: a bunch of Simpson males with the genetic deadly flaw.
Well worth a read !
The Blitzkrieg Legend
Here, for the first time in English, is an illuminating German perspective on the decisive blitzkrieg campaign. The account, written by the German historian Karl-Heinz Frieser and edited by American historian John T. Greenwood, provides the definitive explanation for Germany’s startling success...
books.google.fr
Charlesferdinand
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For those curious about the Pz63 series, I found some details in the Aéro Journal Hors Série 10
Potez 630
Engine: HS14 Ab 10/11
HP: take off: 700 - at sea level: 640 at 4500 m: 720
Speeds: at sea level 390 km/h - at 4500 m: 460 km/h
Potez 631
Engine: GR 14 M4/M5
HP: take off: 700 - at sea level: 570 at 4500 m: 660
Speeds: at sea level 360 km/h - at 4500 m: 442 km/h
As for the question: why did the French Air Force didn't do this or that in 1940, the Luftwaffe has a lot to do with it. Most of these ideas suppose a degree of air superiority/liberty of action that the AdA simply didn't have. Remember, it was essentially organised for the spring offensive of 1919, not for fluid operations. In the chaotic circumstances of May/June, with the pressure of the Luftwaffe, the AdA was a rapidly wasting asset, with poor serviceability and heavy losses. If you start out from historical capabilities, I don't think there is any decision you can take that would make a substantial difference to the outcome.
Potez 630
Engine: HS14 Ab 10/11
HP: take off: 700 - at sea level: 640 at 4500 m: 720
Speeds: at sea level 390 km/h - at 4500 m: 460 km/h
Potez 631
Engine: GR 14 M4/M5
HP: take off: 700 - at sea level: 570 at 4500 m: 660
Speeds: at sea level 360 km/h - at 4500 m: 442 km/h
As for the question: why did the French Air Force didn't do this or that in 1940, the Luftwaffe has a lot to do with it. Most of these ideas suppose a degree of air superiority/liberty of action that the AdA simply didn't have. Remember, it was essentially organised for the spring offensive of 1919, not for fluid operations. In the chaotic circumstances of May/June, with the pressure of the Luftwaffe, the AdA was a rapidly wasting asset, with poor serviceability and heavy losses. If you start out from historical capabilities, I don't think there is any decision you can take that would make a substantial difference to the outcome.
I mostly agree... With AdA independance in 1933, only 7 years to 1940, which also happen to be the worse era in 3rd Republic history (and probably French varied republics, albeit number 1 was quickly aborted by Napoleon 1793-1800, and number 2 by his nephew, 1848-1852) - and the aerospace industry eviscerated in 1936-38... the odds were strong...
But the Armée de Terre, which was older, more confident, and had plenty of excellent equipment, did no better, or perhaps worse. At least the AdA had no huge, senile leadership.
Henri Vuillemin was an honest man but he lacked a personality strong enough to oppose such heavyweights as
- Darlan and De Laborde for the Navy (which their egos the size of a Richelieu battleship)
- plus the plethora of old, arrogant, and senile farts Generals of the Army (countless of them, most truly hating the very idea of an independant Armée de l'Air).
But the Armée de Terre, which was older, more confident, and had plenty of excellent equipment, did no better, or perhaps worse. At least the AdA had no huge, senile leadership.
Henri Vuillemin was an honest man but he lacked a personality strong enough to oppose such heavyweights as
- Darlan and De Laborde for the Navy (which their egos the size of a Richelieu battleship)
- plus the plethora of old, arrogant, and senile farts Generals of the Army (countless of them, most truly hating the very idea of an independant Armée de l'Air).
Thank you for that. The quoted power values at altitude are with ram effect I suppose, being a bit on the optimistic side? Germans give, for 14M, 640 PS at 4000 m.
If the 63X series was designed around the HS 12Y engines or the G&R 14N, that would've meant a substantial power increase, possibly giving the 500 km/h turn of speed. Still not great, though, but not quite the under-performer either.
BTW - Hispano-Suiza was also trying with the 14AA radial engine, size comparable with G&R 14N - yet another stillborn project. HS company would've been best without these two radials, so they can get a V12 engine that is every bit comparable with Merlin or DB 601 in numbers well before 1939. Alas, they friterred the most valuable commodity - time.
Elan Vital
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I wouldn't blame the AdT's leadership for the procurement/doctrine failures of the AdA. The competition only mattered in the case of artillery observation planes, liaison and others and in that case it was more the AdA that was blocking things (this was only solved postwar with the creation of the ALAT). Most of the problems came from the leadership/political/patronal/union level (and to a lesser degree to the technical services' level), like Denain wasting the plan of 1934 by being obsessed with Douhetist concepts and asking for a shitload of aircrafts that the industry simply couldn't deliver when he should have been rebuilding the infrastructure, or the poor nationalisation plan of 36-38, or the inability of the Front Populaire to address the excesses of the unions which contributed to a horrible work environment until 1939.
Also, I understand your frustration at their stupidity but you seem to conflate the worst of the AdT with the entire officer corps. Of course Gamelin was on top and this was enough on its own to screw over the rest of the Army, but there are plenty of officers, old or "young", who were fairly reasonnable with their procurement decisions or doctrinal ideas. To say nothing of the fact that most of the French Army never applied its own doctrine and principles in practice in 1940, due to insufficient training or equipment.
It didn't help that funding was so tight between 1927 and 1936 and the industrial apparatus so deteroriated that the Army or Air Force usually only got enough equipment to test doctrine or unit-scale reliability in 1937, too late to backtrack on mistakes. For example after maneuvers and ballistic testing in 1937, the tank inspectors Gen Dufieux and Velpry both concluded that the light tanks were unsatisfactory in their present state and that funding should be diverted to produce more B1s and D2s instead (still better even with their own flaws). Daladier refused to change production plans and told them to shut up about the vulnerability of the light tanks to not scare the troops.
IMO, a good chunk of the problem really was in the lack of investment in the industry and military after 1927 which is itself related to the economic beliefs of the leading political forces of the time. You can stumble on a good doctrine even with no equipment to test it sometimes, but it's very hard to alter a "bad" doctrine with no equipment to test it (and I mean the equipment that fits the doctrine, not old junk, you can't test armor theories with FTs).
Also, I understand your frustration at their stupidity but you seem to conflate the worst of the AdT with the entire officer corps. Of course Gamelin was on top and this was enough on its own to screw over the rest of the Army, but there are plenty of officers, old or "young", who were fairly reasonnable with their procurement decisions or doctrinal ideas. To say nothing of the fact that most of the French Army never applied its own doctrine and principles in practice in 1940, due to insufficient training or equipment.
It didn't help that funding was so tight between 1927 and 1936 and the industrial apparatus so deteroriated that the Army or Air Force usually only got enough equipment to test doctrine or unit-scale reliability in 1937, too late to backtrack on mistakes. For example after maneuvers and ballistic testing in 1937, the tank inspectors Gen Dufieux and Velpry both concluded that the light tanks were unsatisfactory in their present state and that funding should be diverted to produce more B1s and D2s instead (still better even with their own flaws). Daladier refused to change production plans and told them to shut up about the vulnerability of the light tanks to not scare the troops.
IMO, a good chunk of the problem really was in the lack of investment in the industry and military after 1927 which is itself related to the economic beliefs of the leading political forces of the time. You can stumble on a good doctrine even with no equipment to test it sometimes, but it's very hard to alter a "bad" doctrine with no equipment to test it (and I mean the equipment that fits the doctrine, not old junk, you can't test armor theories with FTs).
ROTFL that's probably true.
The only defence I can think off, is that the top leadership (Gamelin, Georges, Billote - in that order for the Ardennes region, with Corap and Huntziger) truly paralyzed any initiative by the lower echelons...
Not only was the top leadership pretty bad, but it paralyzed / discouraged any improvement from lower.
Some examples
- Gamelin acrimonious relationship with Georges
- nobody listening Billote
- Corap being ignored for Huntziger
- at lower levels: D.C.R commanders (De Gaulle, but also its three colleagues much less known: Bruneau, Bruché, Brocard...) being handled stupid decisions, orders, counter-orders, making their DCR scattered, or without fuel, or send into suicidal missions.
Fundamentally: Georges, Billote and Corap were lucid enough to see the disaster in the making. Yet Gamelin and Huntziger, all by themselves, managed to "cancel" them just with their political influence and sheer stupidity and complacency.
Georges was appalled by Gamelin leadership but could do nothing about it.
Billotte (before his car wreck and death at the worst possible moment, May 21) had clearly seen the Gaulier poontoon bridge was the one and only feeding the German breakthrough, and correctly send whatever bombers that could be scrounged, trying to destroy it.
Corap was all too painfully aware of his Army miseries, but he was trapped between Gamelin and Huntziger and could do nothing either.
That's what infuriates me: there were some valuable people but the Simpsons prevailed.
Three very good blogs, well informed about interbellum French aviation.
Aviadrix is not objective and tends to rant a little too much. still the man is very well informed.
Sam40 is more neutral, and equally well informed. Same for the other one.
On-line translator
sam40-fr.translate.goog
aviadrix-blogspot-com.translate.goog
opolangi-over--blog-com.translate.goog
They have tons of interesting and rare stuff not seen elsewhere.
Aviadrix is not objective and tends to rant a little too much. still the man is very well informed.
Sam40 is more neutral, and equally well informed. Same for the other one.
On-line translator
Aviation | SAM40
sam40-fr.translate.goog
L'aviation selon Drix
Analyses sur l'Histoire de l'Aviation et de notre Défense. La défaite Européenne de Juin 1940 résultait de déficiences crasses : 1) de nos décideurs et 2) des Britanniques, combattant presque sans avions, sans DCA, sans canons anti-chars et à peine 50 chars corrects. - 569 481...
aviadrix-blogspot-com.translate.goog
bombardement - Reconnaissance et Observation
Des articles principalement centrés sur l'aviation de renseignement française en 1939-1940
opolangi-over--blog-com.translate.goog
They have tons of interesting and rare stuff not seen elsewhere.
Charlesferdinand
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Thanks for those links. I'll be checking them out.
One thing for which we can blame the French Army establishment is the insistence that the airforce should be above all the eyes of the AdT. In Le Potez 63.11 au combat (Aéro Journal 43) Ch. Ehrengart mentions that on May 10th observation and reconnaissance represented a full 40% of all operational aircraft on the front line. Apart from a handful of MB174s, these were mostly Pz 637 and 63.11, which were barely adequate, and the rest were obsolete death traps. To add insult to injury, the ground forces proved incapable of reacting quickly and efficiently to the reports of the recce units, obtained at great cost. So when, after May 13th, calls go up to massively intervene in the ground battle, it rings hollow.
Had the Powers that Be not insisted during the rearmament in the late 30s that the AdA should stay out of the ground battle, there might have been a strike force worth mentioning. Even if they had had 200 Fairey Battles instead of Pz63.11, they would have been in a better position to halt the German advance.
One thing for which we can blame the French Army establishment is the insistence that the airforce should be above all the eyes of the AdT. In Le Potez 63.11 au combat (Aéro Journal 43) Ch. Ehrengart mentions that on May 10th observation and reconnaissance represented a full 40% of all operational aircraft on the front line. Apart from a handful of MB174s, these were mostly Pz 637 and 63.11, which were barely adequate, and the rest were obsolete death traps. To add insult to injury, the ground forces proved incapable of reacting quickly and efficiently to the reports of the recce units, obtained at great cost. So when, after May 13th, calls go up to massively intervene in the ground battle, it rings hollow.
Had the Powers that Be not insisted during the rearmament in the late 30s that the AdA should stay out of the ground battle, there might have been a strike force worth mentioning. Even if they had had 200 Fairey Battles instead of Pz63.11, they would have been in a better position to halt the German advance.
You hit the nail, straight on the head. Indeed the Potez series were one of the two modern aircraft available in large numbers by 1939-40 (the other being the MS-406).
Both scored more than 1000 airframes built, a remarquable feat in 1930's France aerospace industry.
Wikipedia tells me
Which doesn't need a translation: a rather astonishing number !
And this is only the 63.11; add the other variants and the tally must be close from 1000 airframes delivered BEFORE June 1940 !
So yes, we could have had a large "Potez 63 striking force" not unlike the British mass of Battles and Blenheim.
Except the bulk of Potez 63 airframes went to reconnaissance.
Take Saint Exupéry GR II/33: they had Potez 637, Potez 63-11 and finally, MB-174.
The case of the Potez 63, crucially shows that a large percentage of the AdA inventory was a mass of tactical reconnaissance / Army cooperation, obsolete aircraft (Les Mureaux etc.) to be replaced by Potez 63-11 - the one with a raised cockpit making it even slower, barely 425 km per hour.
The reason was the Armée de Terre deep hatred of the Armée de l'Air since its independance in 1933; and also the AdT unability to use tactical reconnaissance / army cooperation aircraft like Hs-123 or Fiseler Storch for the LW.
The Potez 63-11 was in fact an (expensive) palliative created after one of the most horrifying failure of the 1930's : the T-3 program.
The T-3 program lasted three years (1936-39) and produced a whole bunch of two engine, three-seat tactical reconnaissance / army cooperation prototypes... that all failed to correctly answered an obtuse RFP, wasted a shitload of money, and industrial power at a crucial juncture.
The AdT ended buying... Potez 63-11s and Caproni Ca-313s (I kid you not) five of them being delivered early June 1940... only day before Mussolini stabbed France in the back !
Drix has a good summary of that quagmire.
Les bimoteurs Hanriot 530 et Dewoitine 720 (et d'autres) "Triplaces de Corps d'Armée et de Travail" dits T3 (Révisé 09 / 07 / 2024 *** ***)
De l'Observation : Rappels succincts L' Observation Aérienne permet à un officier de recueillir des informations tactiques utilisa...
aviadrix-blogspot-com.translate.goog
The T-3 program is often forgotten, but it is typical of all what was dysfuntional with the AdA and AdT procurement, RFPs, dismal relationship...
In passing: the Potez 63 series were so slow and vulnerable, way too many of them ended stored in depots and never used.
----
In France Fights On on June 13 1940 the decision is made to move to Algier and carry on fighting along the British - essentially strangling Vichy in the craddle.
Whatever is useful will cross the Mediterranean, everything else is to be thrown into the LW / WM path to slow it down on its unstoppable march toward Bordeaux, Toulouse and Marseille.
The said depots are thus emptied, and the mass of unused Potez 63 is thrown into the fire: it becomes a bonanza rather than a liability.
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Now I'm deeply disturbed.
I had never realized Potez built so many Potez 63 before June 1940. Whatever the flaws of this aircraft, as a matter of fact it was the one and only multi-engine type available in such large numbers by 1940.
Quick check of the others -
- Breguet build aproximately 200 Breguet 690 series
- Bloch much less MB-170s...
- The larger bombers - Amiot 350 and LeO-451 - did no better.
- American attack bombers were excellent but once again, too few.
How about that... I'm now wondering about a possible "Potez striking force" molded on the British Battle / Blenheim ASF.
Whatever the flaws of the Potez, had it been thrown in large numbers as were the Battles over Sedan, this would have augmented the chances of demolishing the Gaulier poontoon bridge that single-handedly fed the German breakthrough on May 13-14 1940...
Attached: Potez 63 variants and numbers. Makes one think !
I had never realized Potez built so many Potez 63 before June 1940. Whatever the flaws of this aircraft, as a matter of fact it was the one and only multi-engine type available in such large numbers by 1940.
Quick check of the others -
- Breguet build aproximately 200 Breguet 690 series
- Bloch much less MB-170s...
- The larger bombers - Amiot 350 and LeO-451 - did no better.
- American attack bombers were excellent but once again, too few.
How about that... I'm now wondering about a possible "Potez striking force" molded on the British Battle / Blenheim ASF.
Whatever the flaws of the Potez, had it been thrown in large numbers as were the Battles over Sedan, this would have augmented the chances of demolishing the Gaulier poontoon bridge that single-handedly fed the German breakthrough on May 13-14 1940...
Attached: Potez 63 variants and numbers. Makes one think !
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Deltafan
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Even after WW2, HS had difficulty making the versions of the 12 Z reliable ... In 1940, there were already problems to make the 12 Y more reliable beyond the 45 model ...
For the AA, OK, at first, it was unreliable with the Loire 250 fighter prototype and, after, with the LeO 451 bomber prototype. However, at the end, it was finally reliable with the Latécoère 570 bomber prototype and the dutch Koolhoven F.K. 58 fighter prototype, but much too late for its industrialization, in a time when France must deal with the most urgent...
Otherwise, one may wonder what would have happened if Renault, one of the rare French companies of the time with the industrial power to do so, had focused on "big" engines in the early 1930s, rather than on "small" engines (even if the racing ones turned out to be very efficient, as in the case of the Caudron C.460 of the world land plane speed record), which proved ineffective on a fighter such as the Caudron C. 714. The fate of the Renault 14 radial engines (Fas: 1935, 46.5L, 900 hp and 14 Too: 1937, 46.5L, 1020 hp), and their possible planes, could have been different ... But it's only a "What if"...
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Charlesferdinand
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Well, most of the Potez 63s built were the Potez 63.11, the reconnaissance version with the raised cockpit and the glazed nose. This was slower that the fighter/attack versions and essentially unarmed. Theoretically it could take four 50 kg bombs, but only if you dismounted the cameras first, which was time consuming and had to be done by specialists. Ironically the 637, derived from the 631, but with a ventral observer's position, was faster than the 63.11, but seen as an interim model. They really wanted the 63.11.
This for me is the main single thing you could do to improve the capability of the AdA: build something else than the 63.11, an attack version of the 631, for instance, or even Br 693s of Vultee Vengeances if you must.
Also, according to my data, the main difference between the 630 and the 631 is the engine; HS for the 630 and GR for the 631.
This for me is the main single thing you could do to improve the capability of the AdA: build something else than the 63.11, an attack version of the 631, for instance, or even Br 693s of Vultee Vengeances if you must.
Also, according to my data, the main difference between the 630 and the 631 is the engine; HS for the 630 and GR for the 631.
With 730 Potez 63.11 build, any armed variant instead can only help.
For the sake of comparison, its former rival Breguet 690 produced
- 78 Br.691
- 128 Br.693
206 aircraft, of which 78 were unusable.
128 Breguet 693 is six times less than the Potez 63.11 alone, and eight times less than the total number of Potez 63 built.
Makes one think...
One of the main reasons for the success of the Blitzkrieg against the French and British Armies, in May 1940, was the aerial superiority obtained when the Messerschmitt Bf 109 E-3 entered service with the Luftwaffe. It happened at the right time, when the main French fighter Morane-Saulnier M.S.406 was replaced by the second generation fighters Dewoitine D.520 and Arsenal VG 33. During the Phoney War, l’Armée de l’Air tried to fill the gap with the Bloch M.B.152 and Curtiss H.75A fighters, helped by the British Hawker Hurricane Mk.I. But the Messerschmitt would prove superior.
This seems to be the origin of the commonly accepted paradigm about the assumed inferiority of the French technology. It is not common knowledge that France already had operational naval radar in 1934. And that, at the beginning of June 1940, the antiaircraft artillery defending Paris was controlled by the most advanced radar in the world, able to operate in wavelengths from 80 to 16 cm against the 3.5 to 1.5 m of the British or the 2.4 m to 53 cm of the German radar.
The French scientists were also ahead of their German equivalents in the field of nuclear fission. By early 1940, the CNRS controlled the highest reserve in the world of uranium (8 tons coming from the Belgian Congo) and 200 kg of heavy water from the Norwegian enterprise Norsk Hydro.
The French tanks of 1940 had better armour and armament than the Germans. The Marine Française (the French combat fleet) was superior to the Kriegsmarine in firepower with the Béarn carrier and six squadrons of Loire Nieuport L.N.401/411 dive bombers that technically surpassed the German Ju 87.
The destructiveness of the air-to-air weapons installed in the French fighters was slightly higher that their German equivalents, although the quality of the aiming devices OPL 31, RX 39 and GH 38 used by l’Armée de l’Air was somehow inferior to the Zeiss Revi C/12 reflector gunsight of the Luftwaffe. The following text compares the armament used by the French and German fighters during the Battle of France
Designed and built by Manufacture d’Armes in Chatellerault (MAC) during the year 1934, it was the standard machine gun used by the French fighters during the Phoney war and the Battle of France. The commonest model was the MAC 34A (for Aile, the French word for wing), gas operated, electro pneumatically loaded, fed from a helical pan 'drum' magazine containing 300 rounds.
The MAC 34 was installed under the wings of the Morane-Saulnier M.S.406 and Potez 631 fighters in aerodynamic fairings with the drum magazine housed within the wing. The joining system was of the cardan type and could be regulated for convergence at an affective range of 250 m. The mechanism was very sensitive to cold temperatures and might occasionally cause a great firing dispersion.
The belt-feed MAC 34 M39 with 500-675 rounds was developed to solve this problem and reduce drag. It could be installed within the wing of the M.S. 410, Dewoitine D.520, Arsenal V.G. 33 and Bloch M.B.155 which all constituted the 2nd generation of French fighters of the war. There was a variant developed for the M.S.406 exportation version that could be integrated with the engine (firing through the propeller hub) and replaced the H.S.9 cannon. It was a version of the MAC 34A which was fed with a 500 rounds drum.
Another variant with flexible mounting, named MAC 34T (for tourelle, or turret in French) was used in bombers and multiplace fighters. The MAC 34 had a high rate of fire because of the short length of its barrel. Consequently, the muzzle velocity and destruction capacity were reduced up to a point of being considered an inefficient weapon against the He 111, Do 17 and Ju 88 bombers. The MAC 34 fired the short cartridge mod. 1929 with Armour Piercing (AP), Armour Piercing/Incendiary (API) and Armour Piercing Tracer (APT) ammunition. In the M.S. 406 and M.B. 152 the three types of ammunition were sequentially stored in the drums and belts, 40% of AP, 40% of API and 20% of APT.
In the Dewoitine D.520, two machine guns were loaded with AP and the other two with API (a hollowed AP that was then filled with phosphor). The incendiary power of the API was big and its penetration capacity almost non-existent. Additionally, its ballistic features differed from the AP type in the different weight between both bullets. The API was thermally unstable. The heating system of the D.520 weapons had to get disconnected after several cases of spontaneous ignition of the phosphor at temperatures between 40° and 45° C.
Designed to be installed over the engine of the German fighters, it should fire through the propeller disk by means of a synchronization device. Therefore, its rate of fire was lower than that of the MAC 34, a shortage that was partially compensated by the greater capacity of destruction of the projectile, and its higher effective range, due to the use of a long barrel.
It was a recoil operated type weapon designed and built in 1934 by the Rheinmetall Borsig firm. It used an electro pneumatic loading system, with belt feeding, and fired ammunition of the armour piercing (50%), armour piercing/incendiary (40%) and high explosive/incendiary (10%).
The latter, when exploding by impact, informed the pilot that his target had been hit and was used to replace the conventional tracers. The Lutwaffe technical staff thought that the tracers were not convenient during dog fighting as they might alert the enemy pilot of the firing aimed to him.
The Messerschmitt Bf 109 E-1 carried two MG 17 over the engine with 1000 rounds per gun (r.p.g.) and another two in the wings with 420 r.p.g. having a total weight of fire of 0.72 kg/sec. This disadvantageously compared to the 2 kg/sec of the Morane-Saulnier M.S.406 and the 1.46 kg/sec of the Hawker Hurricane Mk.I.
To balance this situation the Bf 109 E-3 (with a firepower of 2.66 kg/sec) entered service at the beginning of the autumn of 1939, replacing the MG 17 of the wings with two MG FF cannons.
The Messerschmitt Bf 110 heavy fighters of the C series also took part in the Battle of France. They were equipped with four MG 17 machine guns with 1000 r.p.g. and two 20 mm MG FF cannons with 180 r.p.g. located in the nose.
During the 20s, the Swiss firm SEMAG committed itself to the design of the 20 mm gun Becker used during the WWI by some German bombers. During the first years of the 30s, the research was continued by the Swiss firm Oerlikon who, in 1933, started to commercialize three basic models using cartridges of progressive length and power. They were the Oerlikon FFF type (72 mm case length), the Oerlikon FFL type (100 mm case length) and the Oerlikon FFS type (110 mm case length).
The FFS was acquired by l’Armèe de l’Air to serve as a base for its own Hispano Suiza H.S.7 and H.S.9 designs which were both modified for aircraft engine mounting. The FFL was acquired by the Imperial Japanese Navy in 1939 and manufactured under license from 1941 onwards, as 99-2 Type, to be used in the Zero-Sen fighters. The FFF was chosen by the German, Polish and Romanian Air Forces to equip the Bf 109 E-2/E-3, Bf 110C, PZL P-24 C/F/G and IAR 80 fighters.
The Luftwaffe version was extensively modified to adapt the original design to the German production techniques, being mass manufactured by the Ikaria Werke Berlin as MG FF (Maschinen Gewehr Flügel Fest = Machine Gun Wing Installation) from 1935 onwards. It was the lightest short barrelled weapon in its class with just 28 kg. But it had a lower effective range and power of penetration than the contemporary French and Swiss designs.
These shortages were partially compensated by a higher rate of fire and the introduction of the MG FFM (Modifizierung = Modification) which could fire the HE ammunitions Minengeschoss.
It is unclear if the MG FFM was ever used during the Battle of France. Some authors state that the Bf 109 E-2 were armed with four MG 17 machine guns and at 20 mm cannon located behind the engine, firing through the axis of the hub propeller. As per this version of facts, the 'M' meant Motor.
The Bf 109 E-2 passed through some operational tests with discouraging results because of the strong vibrations that the cannon produced in the engine crankcase during firing. Apparently, the decision to mount the two cannons in the wings of the Bf 109 E-3 went against the initial German project that preferred the French moteur-canon device. This system was eventually adopted as a matter of urgency after the failure of the Bf 109 E-2 to alleviate the big difference in firepower between the Bf 109 E-1 and the Morane and Hurricane fighters.
The MG FF fired 20 mm ammunition of the 20 x 80RB type that could be HE (134 g), HEI (115 g) or M-Geschoss (92 g). When installed in the Bf 109 E and Bf 110 C fighters of, it used a 60 rounds drum while the Do 17Z night fighters used a 15-45 rounds drum which could be manually replaced in combat. The Luftwaffe always considered the MG FF a transition weapon to fill the gap until the excellent MG 151 was available.
A small amount of these guns, together with their manufacturing license, was acquired by France in 1933. The FFS was not suitable for aircraft engine mounting because of the too advanced position of the recovery cylinder/yoke unit and had to be modified as Hispano-Suiza H.S.7. The French developed the SPAD S.XII in 1916 for the destruction of balloons. It was armed with a single-shot SAMC (APX) 37 mm cannon mounted between the V8 cylinder blocks of the 200 hp Hispano-Suiza 8c engine.
The moteur-canon was not very successful, due to its slow reloading capacity and excessive recoil shock, and the SPAD S.XII was abandoned, but the French retained the idea until the arrival of the right time. This came in 1932 with the 690 hp liquid-cooled engine Hispano-Suiza H.S.12 Xbrs of 12 cylinders in 60º 'Vee' configuration.
This was the right engine to combine with one 20 mm Oerlikon FFS cannon -manufactured under license as Hispano-Suiza H.S.7- mounted between the two-cylinder banks. The crankcase was strengthened, and the reduction gear modified to bring the hollow propeller shaft in line with the gun barrel.
The ammunition was the same than that of the Swiss gun, contained in a 60 rounds drum. The H.S.7 was heavier, due to the fixation system to the engine, and had a rate of fire of just 350 rpm (compared to the 470 rpm of the Oerlikon) to protect the engine from any destructive vibration. This engine was then known as Hispano-Suiza 12 Xcrs (‘c’ for canon = cannon) and had reduced its power to 680 hp, consequence of the modifications made in the gearbox. The new moteur-canon was installed in the Dewoitine D.510 fighter and in the Loire-Nieuport L.N. 401/411 dive bombers of l’Aeronavale which fought the panzers on 15 May 1940.
The Germans tried to use the moteur-canon system with their Bf 109 V4, C-2 and E-2 fighters, trying different combinations of Jumo 210 and Daimler Benz 601 engines with MG 17 machine guns and MG FF cannons. But they found insoluble problems of cooling and crankcase destructive vibrations. On October 1940, they finally adapted an MG FF cannon behind the DB 601N engine of the Bf 109 F-0, but the device suffered structural damages during tests. The problem could not be solved until the MG 151/20 gun was available and could be installed in the Bf 109 F-2 in March 1941.
In 1935 a 900 hp improved version of the H.S.12 Xcrs engine appeared, known as Hispano-Suiza H.S.12 Ycrs. The integrated cannon was also an improved version of the H.S.7 although somehow lighter and with 420 rounds per minute (r.p.m.) rate of fire but maintaining the same muzzle velocity and destructive power than the Oerlikon. It fired the same type of HE, HET and AP ammunition than the Oerlikon, stored in a 60 rounds drum.
The HE type model 1936 was identified by a yellow band, the HET of 1939 with a yellow and blue band and the AP was overall painted in black. The HE had a 1937 model 17/19 B impact fuse and the HET also had a self-destruction system. The moteur-canon was very successful in the market, being acquired by the Czech Air Force to equip their Avia B-534, B-536 and B-135 fighters and by the Yugoslavian Air Force for their Ikarus Ik-2 and Rogozarski Ik-3. It was also used by l’Armèe de l’Air to power the Morane-Saulnier M.S.405.
After the experience in combat against the fast and well armoured He 111 and Do 17 German bombers obtained during the Spanish Civil War, the engine designer Mark Birkigt decided to develop the H.S. 404 with higher performance. It was gas operated with a 166 per cent higher rate of fire and a muzzle velocity of 880 m/sec compared to the 820 m/sec of the H.S.9. The new weapon entered service in 1939 and could be installed either in the H.S.12 Y-31 engines of the M.S. 406 or in the H.S.12 Y-45 of the Dewoitine D.520, M.B. 155 and Arsenal VG 33 fighters.
The H.S. 404 fired 20x110 ammunition (that was not interchangeable with the 20x110 RB cartridges of the H.S .9) stored in a 60 rounds drum. There were six different types: HE model 1938 or 1939 (130 g) with a 17/19B 1938 model fuse identified by a yellow band, HET identified by a yellow and a blue-grey band, AP (165 g) black projectile with a red band, APT with black nose and metal-grey-metal-red bands, AP/HE with red-yellow-green bands and HEI with red-yellow-blue bands.
This type of ammunition had not been sufficiently tested and caused several accidents during combat. The Dewoitines D.520 of the G.C.I/3 were specially affected, experiencing premature explosions within the barrel when firing the second burst. Between 5 and 8 June 1940 the M.S.406 of the G.C.I/6, G.C.II/2 and G.C.III/7 were used in ground attack task against the German tanks with AP and APT ammunition.
The manufacturing of the H.S. 404 was slow and costly. At the beginning of the war only 928 units had been delivered to l’Armée de l’Air and in March 1940 there were 2,319 units available.
The H.S. 404 was a formidable weapon when integrated in a Hispano-Suiza engine or installed in the nose of the twin engine Potez 631 fighters. However, it was less resilient when installed in the wings of the Bloch fighters, causing different problems of vibration, stoppage, freezing and dispersion of firing.
The H.S. 404 was acquired by the RAF and manufactured under license in the United Kingdom as Hispano-Suiza Mk I, Mk II and Mk V and as Hispano AN/M2 in the USA. A version over flexible mounting was also manufactured to be used by the rear gunners of the French medium bombers LeO 451 and Amiot 354.
This seems to be the origin of the commonly accepted paradigm about the assumed inferiority of the French technology. It is not common knowledge that France already had operational naval radar in 1934. And that, at the beginning of June 1940, the antiaircraft artillery defending Paris was controlled by the most advanced radar in the world, able to operate in wavelengths from 80 to 16 cm against the 3.5 to 1.5 m of the British or the 2.4 m to 53 cm of the German radar.
The French scientists were also ahead of their German equivalents in the field of nuclear fission. By early 1940, the CNRS controlled the highest reserve in the world of uranium (8 tons coming from the Belgian Congo) and 200 kg of heavy water from the Norwegian enterprise Norsk Hydro.
The French tanks of 1940 had better armour and armament than the Germans. The Marine Française (the French combat fleet) was superior to the Kriegsmarine in firepower with the Béarn carrier and six squadrons of Loire Nieuport L.N.401/411 dive bombers that technically surpassed the German Ju 87.
The destructiveness of the air-to-air weapons installed in the French fighters was slightly higher that their German equivalents, although the quality of the aiming devices OPL 31, RX 39 and GH 38 used by l’Armée de l’Air was somehow inferior to the Zeiss Revi C/12 reflector gunsight of the Luftwaffe. The following text compares the armament used by the French and German fighters during the Battle of France
MAC 34 (7.5 mm)
Designed and built by Manufacture d’Armes in Chatellerault (MAC) during the year 1934, it was the standard machine gun used by the French fighters during the Phoney war and the Battle of France. The commonest model was the MAC 34A (for Aile, the French word for wing), gas operated, electro pneumatically loaded, fed from a helical pan 'drum' magazine containing 300 rounds.
The MAC 34 was installed under the wings of the Morane-Saulnier M.S.406 and Potez 631 fighters in aerodynamic fairings with the drum magazine housed within the wing. The joining system was of the cardan type and could be regulated for convergence at an affective range of 250 m. The mechanism was very sensitive to cold temperatures and might occasionally cause a great firing dispersion.
The belt-feed MAC 34 M39 with 500-675 rounds was developed to solve this problem and reduce drag. It could be installed within the wing of the M.S. 410, Dewoitine D.520, Arsenal V.G. 33 and Bloch M.B.155 which all constituted the 2nd generation of French fighters of the war. There was a variant developed for the M.S.406 exportation version that could be integrated with the engine (firing through the propeller hub) and replaced the H.S.9 cannon. It was a version of the MAC 34A which was fed with a 500 rounds drum.
Another variant with flexible mounting, named MAC 34T (for tourelle, or turret in French) was used in bombers and multiplace fighters. The MAC 34 had a high rate of fire because of the short length of its barrel. Consequently, the muzzle velocity and destruction capacity were reduced up to a point of being considered an inefficient weapon against the He 111, Do 17 and Ju 88 bombers. The MAC 34 fired the short cartridge mod. 1929 with Armour Piercing (AP), Armour Piercing/Incendiary (API) and Armour Piercing Tracer (APT) ammunition. In the M.S. 406 and M.B. 152 the three types of ammunition were sequentially stored in the drums and belts, 40% of AP, 40% of API and 20% of APT.
In the Dewoitine D.520, two machine guns were loaded with AP and the other two with API (a hollowed AP that was then filled with phosphor). The incendiary power of the API was big and its penetration capacity almost non-existent. Additionally, its ballistic features differed from the AP type in the different weight between both bullets. The API was thermally unstable. The heating system of the D.520 weapons had to get disconnected after several cases of spontaneous ignition of the phosphor at temperatures between 40° and 45° C.
Rheinmetall Borsig MG 17 (7.92 mm.)
Designed to be installed over the engine of the German fighters, it should fire through the propeller disk by means of a synchronization device. Therefore, its rate of fire was lower than that of the MAC 34, a shortage that was partially compensated by the greater capacity of destruction of the projectile, and its higher effective range, due to the use of a long barrel.
It was a recoil operated type weapon designed and built in 1934 by the Rheinmetall Borsig firm. It used an electro pneumatic loading system, with belt feeding, and fired ammunition of the armour piercing (50%), armour piercing/incendiary (40%) and high explosive/incendiary (10%).
The latter, when exploding by impact, informed the pilot that his target had been hit and was used to replace the conventional tracers. The Lutwaffe technical staff thought that the tracers were not convenient during dog fighting as they might alert the enemy pilot of the firing aimed to him.
The Messerschmitt Bf 109 E-1 carried two MG 17 over the engine with 1000 rounds per gun (r.p.g.) and another two in the wings with 420 r.p.g. having a total weight of fire of 0.72 kg/sec. This disadvantageously compared to the 2 kg/sec of the Morane-Saulnier M.S.406 and the 1.46 kg/sec of the Hawker Hurricane Mk.I.
To balance this situation the Bf 109 E-3 (with a firepower of 2.66 kg/sec) entered service at the beginning of the autumn of 1939, replacing the MG 17 of the wings with two MG FF cannons.
The Messerschmitt Bf 110 heavy fighters of the C series also took part in the Battle of France. They were equipped with four MG 17 machine guns with 1000 r.p.g. and two 20 mm MG FF cannons with 180 r.p.g. located in the nose.
Ikaria MG FF (20 mm.)
During the 20s, the Swiss firm SEMAG committed itself to the design of the 20 mm gun Becker used during the WWI by some German bombers. During the first years of the 30s, the research was continued by the Swiss firm Oerlikon who, in 1933, started to commercialize three basic models using cartridges of progressive length and power. They were the Oerlikon FFF type (72 mm case length), the Oerlikon FFL type (100 mm case length) and the Oerlikon FFS type (110 mm case length).
The FFS was acquired by l’Armèe de l’Air to serve as a base for its own Hispano Suiza H.S.7 and H.S.9 designs which were both modified for aircraft engine mounting. The FFL was acquired by the Imperial Japanese Navy in 1939 and manufactured under license from 1941 onwards, as 99-2 Type, to be used in the Zero-Sen fighters. The FFF was chosen by the German, Polish and Romanian Air Forces to equip the Bf 109 E-2/E-3, Bf 110C, PZL P-24 C/F/G and IAR 80 fighters.
The Luftwaffe version was extensively modified to adapt the original design to the German production techniques, being mass manufactured by the Ikaria Werke Berlin as MG FF (Maschinen Gewehr Flügel Fest = Machine Gun Wing Installation) from 1935 onwards. It was the lightest short barrelled weapon in its class with just 28 kg. But it had a lower effective range and power of penetration than the contemporary French and Swiss designs.
These shortages were partially compensated by a higher rate of fire and the introduction of the MG FFM (Modifizierung = Modification) which could fire the HE ammunitions Minengeschoss.
It is unclear if the MG FFM was ever used during the Battle of France. Some authors state that the Bf 109 E-2 were armed with four MG 17 machine guns and at 20 mm cannon located behind the engine, firing through the axis of the hub propeller. As per this version of facts, the 'M' meant Motor.
The Bf 109 E-2 passed through some operational tests with discouraging results because of the strong vibrations that the cannon produced in the engine crankcase during firing. Apparently, the decision to mount the two cannons in the wings of the Bf 109 E-3 went against the initial German project that preferred the French moteur-canon device. This system was eventually adopted as a matter of urgency after the failure of the Bf 109 E-2 to alleviate the big difference in firepower between the Bf 109 E-1 and the Morane and Hurricane fighters.
The MG FF fired 20 mm ammunition of the 20 x 80RB type that could be HE (134 g), HEI (115 g) or M-Geschoss (92 g). When installed in the Bf 109 E and Bf 110 C fighters of, it used a 60 rounds drum while the Do 17Z night fighters used a 15-45 rounds drum which could be manually replaced in combat. The Luftwaffe always considered the MG FF a transition weapon to fill the gap until the excellent MG 151 was available.
Oerlikon FFS (20 mm)
A small amount of these guns, together with their manufacturing license, was acquired by France in 1933. The FFS was not suitable for aircraft engine mounting because of the too advanced position of the recovery cylinder/yoke unit and had to be modified as Hispano-Suiza H.S.7. The French developed the SPAD S.XII in 1916 for the destruction of balloons. It was armed with a single-shot SAMC (APX) 37 mm cannon mounted between the V8 cylinder blocks of the 200 hp Hispano-Suiza 8c engine.
The moteur-canon was not very successful, due to its slow reloading capacity and excessive recoil shock, and the SPAD S.XII was abandoned, but the French retained the idea until the arrival of the right time. This came in 1932 with the 690 hp liquid-cooled engine Hispano-Suiza H.S.12 Xbrs of 12 cylinders in 60º 'Vee' configuration.
This was the right engine to combine with one 20 mm Oerlikon FFS cannon -manufactured under license as Hispano-Suiza H.S.7- mounted between the two-cylinder banks. The crankcase was strengthened, and the reduction gear modified to bring the hollow propeller shaft in line with the gun barrel.
The ammunition was the same than that of the Swiss gun, contained in a 60 rounds drum. The H.S.7 was heavier, due to the fixation system to the engine, and had a rate of fire of just 350 rpm (compared to the 470 rpm of the Oerlikon) to protect the engine from any destructive vibration. This engine was then known as Hispano-Suiza 12 Xcrs (‘c’ for canon = cannon) and had reduced its power to 680 hp, consequence of the modifications made in the gearbox. The new moteur-canon was installed in the Dewoitine D.510 fighter and in the Loire-Nieuport L.N. 401/411 dive bombers of l’Aeronavale which fought the panzers on 15 May 1940.
The Germans tried to use the moteur-canon system with their Bf 109 V4, C-2 and E-2 fighters, trying different combinations of Jumo 210 and Daimler Benz 601 engines with MG 17 machine guns and MG FF cannons. But they found insoluble problems of cooling and crankcase destructive vibrations. On October 1940, they finally adapted an MG FF cannon behind the DB 601N engine of the Bf 109 F-0, but the device suffered structural damages during tests. The problem could not be solved until the MG 151/20 gun was available and could be installed in the Bf 109 F-2 in March 1941.
Hispano-Suiza H.S. 9 (20 mm)
In 1935 a 900 hp improved version of the H.S.12 Xcrs engine appeared, known as Hispano-Suiza H.S.12 Ycrs. The integrated cannon was also an improved version of the H.S.7 although somehow lighter and with 420 rounds per minute (r.p.m.) rate of fire but maintaining the same muzzle velocity and destructive power than the Oerlikon. It fired the same type of HE, HET and AP ammunition than the Oerlikon, stored in a 60 rounds drum.
The HE type model 1936 was identified by a yellow band, the HET of 1939 with a yellow and blue band and the AP was overall painted in black. The HE had a 1937 model 17/19 B impact fuse and the HET also had a self-destruction system. The moteur-canon was very successful in the market, being acquired by the Czech Air Force to equip their Avia B-534, B-536 and B-135 fighters and by the Yugoslavian Air Force for their Ikarus Ik-2 and Rogozarski Ik-3. It was also used by l’Armèe de l’Air to power the Morane-Saulnier M.S.405.
Hispano Suiza H.S. 404 (20 mm)
After the experience in combat against the fast and well armoured He 111 and Do 17 German bombers obtained during the Spanish Civil War, the engine designer Mark Birkigt decided to develop the H.S. 404 with higher performance. It was gas operated with a 166 per cent higher rate of fire and a muzzle velocity of 880 m/sec compared to the 820 m/sec of the H.S.9. The new weapon entered service in 1939 and could be installed either in the H.S.12 Y-31 engines of the M.S. 406 or in the H.S.12 Y-45 of the Dewoitine D.520, M.B. 155 and Arsenal VG 33 fighters.
The H.S. 404 fired 20x110 ammunition (that was not interchangeable with the 20x110 RB cartridges of the H.S .9) stored in a 60 rounds drum. There were six different types: HE model 1938 or 1939 (130 g) with a 17/19B 1938 model fuse identified by a yellow band, HET identified by a yellow and a blue-grey band, AP (165 g) black projectile with a red band, APT with black nose and metal-grey-metal-red bands, AP/HE with red-yellow-green bands and HEI with red-yellow-blue bands.
This type of ammunition had not been sufficiently tested and caused several accidents during combat. The Dewoitines D.520 of the G.C.I/3 were specially affected, experiencing premature explosions within the barrel when firing the second burst. Between 5 and 8 June 1940 the M.S.406 of the G.C.I/6, G.C.II/2 and G.C.III/7 were used in ground attack task against the German tanks with AP and APT ammunition.
The manufacturing of the H.S. 404 was slow and costly. At the beginning of the war only 928 units had been delivered to l’Armée de l’Air and in March 1940 there were 2,319 units available.
The H.S. 404 was a formidable weapon when integrated in a Hispano-Suiza engine or installed in the nose of the twin engine Potez 631 fighters. However, it was less resilient when installed in the wings of the Bloch fighters, causing different problems of vibration, stoppage, freezing and dispersion of firing.
The H.S. 404 was acquired by the RAF and manufactured under license in the United Kingdom as Hispano-Suiza Mk I, Mk II and Mk V and as Hispano AN/M2 in the USA. A version over flexible mounting was also manufactured to be used by the rear gunners of the French medium bombers LeO 451 and Amiot 354.
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On 10 May 1940 l’Armée de l’Air had five Escadrilles de Chasse de Nuit with forty-seven Potez 631 night fighters. These aircraft were operating in sectors of the front that were 15 km wide and 20 km deep, helped by searchlights and sound locators, with one control centre positioning the airplanes by using direction finding (D/F) equipment. Depending on conditions of visibility, a night fighter pilot could see an unilluminated bomber from between 400 and 600 m, and between 1,000 and 6,000 when illuminated by searchlights. During the Battle of France, the Potez 63 managed to shoot down three Heinkel He 111 and one Dornier Do 17.
The failure of the M.B.151 and the delays in the delivery of the M.B.152 forced l’Armée de l’Air to maintain various types of obsolete fighters in service. The Dewoitine D.510, that constituted 70 per cent of the French fighter force during the Munich Agreement, still equipped five Groupes de Chasse and two Escadrilles of the Aéronavale (141 aircraft) at the time of the Poland invasion. At the beginning of 1940 two Patrouilles de Défense were still active with 40 aircraft piloted by Poles.
On September 1939 one Escadrille of the Armée de l’Air equipped with Dewoitine D.371 fighters were based in Bizerte-Tunis and the Aéronavale still used thirteen D.373 and D.376 aircraft. When the war started, three Groupes de Chasse, still equipped with Loire 46 fighters, were making the transition to the M.S. 406. By May 1940 twenty-three aircraft were left in various training schools and sixteen in reserve.
Some old biplanes of the Blériot-SPAD 510 type were got back into service in the Grupe Aérien Régional de Chasse at Le Havre-Octeville and in the Centre d’Instruction à la Chasse at Montpellier, being gradually replaced by the Bloch M.B.151.
The failure of the M.B.151 and the delays in the delivery of the M.B.152 forced l’Armée de l’Air to maintain various types of obsolete fighters in service. The Dewoitine D.510, that constituted 70 per cent of the French fighter force during the Munich Agreement, still equipped five Groupes de Chasse and two Escadrilles of the Aéronavale (141 aircraft) at the time of the Poland invasion. At the beginning of 1940 two Patrouilles de Défense were still active with 40 aircraft piloted by Poles.
On September 1939 one Escadrille of the Armée de l’Air equipped with Dewoitine D.371 fighters were based in Bizerte-Tunis and the Aéronavale still used thirteen D.373 and D.376 aircraft. When the war started, three Groupes de Chasse, still equipped with Loire 46 fighters, were making the transition to the M.S. 406. By May 1940 twenty-three aircraft were left in various training schools and sixteen in reserve.
Some old biplanes of the Blériot-SPAD 510 type were got back into service in the Grupe Aérien Régional de Chasse at Le Havre-Octeville and in the Centre d’Instruction à la Chasse at Montpellier, being gradually replaced by the Bloch M.B.151.
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Elan Vital
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Well, maybe Potez had more production capacity than Breguet at the time, and due to the Breguet not getting its engines as early as the Potez it was substantially delayed to production. The Breguet was a slightly better airframe aerodynamically, but as it first flew later than the Potez due to a lack of test engines it was not chosen as the primary aircraft of the type.
The Potez definitely was excellent from a mass production point of view, the only one capable of this in the MS-406/Potez/Leo 45 trio.
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How to put it politely ?
A yes, the French shoot themselves in the foots...
the reason are simple
1. rebuild the glorious Republic, special the devastated Industrial zone under German occupation.
2. Pay off a gigantic pile of debts to Britain and USA (in facto in last years of War Britain was running french war finances)
have they pay them off over time ?
3. French Politic became after WW1 turbulent, during great Depression it became Chaotic !
with allot Stop and Go in projects, special if government changes.
4. most of those Politician believed the treaty of Versailles would protect France, tell that to certain litte annoying Austrian...
5. The Military thinking in WW1 standard, not focus in Airforce but in old fashion infantry in bunkers.
but in defence all in Europe was thinking in that mind set, except The Third Reich, Britain and USA.
France learned from this painful lesson, now there a Nuclear power...
A yes, the French shoot themselves in the foots...
the reason are simple
1. rebuild the glorious Republic, special the devastated Industrial zone under German occupation.
2. Pay off a gigantic pile of debts to Britain and USA (in facto in last years of War Britain was running french war finances)
have they pay them off over time ?
3. French Politic became after WW1 turbulent, during great Depression it became Chaotic !
with allot Stop and Go in projects, special if government changes.
4. most of those Politician believed the treaty of Versailles would protect France, tell that to certain litte annoying Austrian...
5. The Military thinking in WW1 standard, not focus in Airforce but in old fashion infantry in bunkers.
but in defence all in Europe was thinking in that mind set, except The Third Reich, Britain and USA.
France learned from this painful lesson, now there a Nuclear power...
Despite all its political and economic problems, France was an industrial giant with great human potential, good allies, an overseas colonial empire and almost inexhaustible food reserves. Its failure was due to a political mismanagement of the enormous military resources available.
"Nous sommes trahis".
"Nous sommes trahis".
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Thanky for the overview.
Some remarks, FWIW. French might've had the radar (they also received a handful of British sets), what mattered was existence of radar-assisted air defence network. They didn't have that. The network needed a capable 'pointy end' - modern fighter aircraft - in good numbers; again, that was not present in France.
Germany had all of that, so did the RAF in the UK.
Germans had radios in wide-scale use, the French did not. Germany also have had a workable doctrine, French didn't. One-man turrets were standard of the Great war, Germans and British moved to 2- and 3-men turrets by 1939.
That's debatable. Yes, these dive-bombers were capable to work from carriers, the Ju 87 carried more (up to 1000 kg bomb + drop tanks + armor for the Ju-87R in 1940, 1000 HP engine).
Bf 109E-3 entered the service much earlier. 153 were delivered to the LW before 31st December 1938, compared with only 15 of 109E-1s. Another 169 of E-3s were delivered in the 1st 3 months of 1939. (source: "German aircraft industry and production 1933-45" by Vajda & Dancey, pg.46 and 48)
There was no Bf 109E-2.
MG FFM indeed means 'MG FF that is modified to fire the M-geschoss ammo'; ammo was not interchangable between the FF and FFM (FFM used weaker main spring since the ammo had less propellant, thus it could still cycle).
Bf 109E-3 carried two cannons for each one carried by French fighters. So each fighter type had it's strong and weak points armament-vise.
Not sure where from the comment 'had reduced it's power' came from. Whether they were capable to carry a cannon in the Vee or no, power was same on HS 12X engines.
The 'bigger' HS-12Y produced more power, just like the Merlin made more power than Kestrel.
Hi Justo,
That's an interesting observation! Sources regarding the Luftwaffe thinking at the time would be highly welcome, and I think yoiu might be on to something as this would fit Lützow's thinking at least. Lützow, as an instructor at the fighter school at Schleißheim, cooperated with Wolfgang Falck and Hannes Trautloft on a fighter training manual which went by the title of "Der Jagdflieger in der Ausbildung" ('The Fighter Pilot in Training'), and was unofficially called "Der kleine Trautloft" ('The little Trautloft'). Lützow based on his Spanish Civil War experience considered a high muzzle velocity and highly destructive explosive rounds as superior to a larger number of rapid-fire (machine) guns, and the MG FF might indeed fall short of the "high muzzle velocity" criterion. Subsequently, Lützow was ordered to Berlin to formally evaluate the Spanish Civil War experience, and seems to have authored one or two more papers in 1938, so his thinking might indeed have influenced Luftwaffe decision in the way you described. (I'm relying on "Gott oder ein Flugzeug" by Braatz for all of this.)
With regard to the MG FF ammunition feed, according to the RLM datasheets reproduced in Bukowski/Griehl's "Junkersflugzeuge 1933 - 1945" were the M-15FF (M = Magazin, a 15-round banana magazin), and the T-30-FF, T-60-FF and T-90-FF drums (T = Trommel, 'drum'). The 60 round drum in the Me 110 was changed by hand, so I'm not sure it couldn't have been used in the Do 17Z too. The 90 round drum seems to have been a later development that fit into the same space as the 60 round drum, and it shows up on some Fw 190A-5 data sheets at least.
I believe the Me 109E-2 didn't actually reach operational status, and the Me 109E-3 seems to have been prepared even before the war as there is a Luftwaffe Manualv around (LDv 282/2, see http://109lair.hobbyvista.com/index1024.htm ) that describes the MG FF wing cannon armament of the Bf 109C-3, which basically was the installation we know from the E-3 in the older Jumo-powered airframe. So at least the engineering was not a rush-job based on war experience, but part of the systematic expansion of the Luftwaffe in pre-war times.
Regards,
Henning (HoHun)
That's an interesting observation!
Sources regarding the Luftwaffe thinking at the time would be highly welcome, and I think yoiu might be on to something as this would fit Lützow's thinking at least. Lützow, as an instructor at the fighter school at Schleißheim, cooperated with Wolfgang Falck and Hannes Trautloft on a fighter training manual which went by the title of "Der Jagdflieger in der Ausbildung" ('The Fighter Pilot in Training'), and was unofficially called "Der kleine Trautloft" ('The little Trautloft'). Lützow based on his Spanish Civil War experience considered a high muzzle velocity and highly destructive explosive rounds as superior to a larger number of rapid-fire (machine) guns, and the MG FF might indeed fall short of the "high muzzle velocity" criterion. Subsequently, Lützow was ordered to Berlin to formally evaluate the Spanish Civil War experience, and seems to have authored one or two more papers in 1938, so his thinking might indeed have influenced Luftwaffe decision in the way you described. (I'm relying on "Gott oder ein Flugzeug" by Braatz for all of this.)With regard to the MG FF ammunition feed, according to the RLM datasheets reproduced in Bukowski/Griehl's "Junkersflugzeuge 1933 - 1945" were the M-15FF (M = Magazin, a 15-round banana magazin), and the T-30-FF, T-60-FF and T-90-FF drums (T = Trommel, 'drum'). The 60 round drum in the Me 110 was changed by hand, so I'm not sure it couldn't have been used in the Do 17Z too. The 90 round drum seems to have been a later development that fit into the same space as the 60 round drum, and it shows up on some Fw 190A-5 data sheets at least.
I believe the Me 109E-2 didn't actually reach operational status, and the Me 109E-3 seems to have been prepared even before the war as there is a Luftwaffe Manualv around (LDv 282/2, see http://109lair.hobbyvista.com/index1024.htm ) that describes the MG FF wing cannon armament of the Bf 109C-3, which basically was the installation we know from the E-3 in the older Jumo-powered airframe. So at least the engineering was not a rush-job based on war experience, but part of the systematic expansion of the Luftwaffe in pre-war times.
Regards,
Henning (HoHun)
Ikaria press materials dated 1935 were offering the MG FF.
Mauser received the contract for a 15mm belt-fed synchronisable cannon with high MV in 1934 (per 'Fligzeug bewaffnung' by Schliephake), that eventually became the MG 151/15.
It is worth mentioning that the Luftwaffe were initially interested in a very high-velocity motor-cannon, the 2cm MG C/30L, which fired the same 20 x 138B ammunition as the Flak cannon. This was tested in a prototype He 112 in Spain, and found to be very effective in ground attack against vehicles but too slow-firing against aircraft (the rate of fire was 300-350 rpm). Ammunition supply was via a huge 100-round drum mounted under the gun. After that experience, the Luftwaffe chose a high rate of fire instead of high velocity (c. 1000 rpm for 2 x MG FF).
P.S. you can find details of the armament performance, as well as photos of the ammunition, here: https://www.quarryhs.co.uk/WW2guneffect.htm
Talking about guns... ever wondered why every single freakkin' French interbellum multi-engine type had a TWIN TAIL ?
I mean, every single of them
- Potez 63, Breguet 690, MB-170
- LeO-451 & Amiot 350
- frack, we even forced Douglas to build a twin tail DB-7 prototype in 1939
(hint: it was a bad idea and was quickly dropped)
The reason: MAC-34 MG to defend the rear. Ok, not a bad idea per se. Although the machine gun was a bit light to truly damage an attacking Me-109.
But the larger bombers had a HS-404 there ! A 20 mm defensive gun... only B-52H have that !
Alas... main problem was the gun wasn't powered at all. IT was the gunner who had to move it... and change the 60 shell drum weighing 25 kg. In flight.
As proven by the Leo-451, it wasn't an efficient defensive weapon for the reasons above, plus it forced the twin tail: heavier, draggier... when French aircraft were already lagging behind in engine power.
Another nail in the AdA (and France) coffin. Plus, I realize now by looking at @Justo Miranda numbers, there wasn't that much HS-404s to share or waste, for fighters: production was slow.
And yet they put many of them as defensive weapons on LeO-451s...
I mean, every single of them
- Potez 63, Breguet 690, MB-170
- LeO-451 & Amiot 350
- frack, we even forced Douglas to build a twin tail DB-7 prototype in 1939
(hint: it was a bad idea and was quickly dropped)
The reason: MAC-34 MG to defend the rear. Ok, not a bad idea per se. Although the machine gun was a bit light to truly damage an attacking Me-109.
But the larger bombers had a HS-404 there ! A 20 mm defensive gun... only B-52H have that !
Alas... main problem was the gun wasn't powered at all. IT was the gunner who had to move it... and change the 60 shell drum weighing 25 kg. In flight.
As proven by the Leo-451, it wasn't an efficient defensive weapon for the reasons above, plus it forced the twin tail: heavier, draggier... when French aircraft were already lagging behind in engine power.
Another nail in the AdA (and France) coffin. Plus, I realize now by looking at @Justo Miranda numbers, there wasn't that much HS-404s to share or waste, for fighters: production was slow.
And yet they put many of them as defensive weapons on LeO-451s...
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Methinks that you're pointing the finger in the wrong direction. Be it single tail or twin tail, it does not matter.
In the case of the DB-7 it was proven the twin tail degraded performances.
And look at the (weird) twin tails on the LeO-451: they made the plane tricky to fly. The LeO was fast but it had dangerous landing characteristics and got a lot of crashes.
But this is only a minor detail. We agree on the fact that a) a 20 mm gun (except on a B-52 much later) is not a good defensive weapon
and b) it deprived French fighters from much needed guns.
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I still believe that we should have built more Potez 631 / 633 / 637 rather than 730+ unarmed Potez 63.11; and thrown every single of them at that Gaulier poontoon bridge after the Breguet 693s were slaughtered too early.
Perhaps the best way would have been to focuse on LN-161 early, D-520 later, and as much Potez 63 "bombers / attack" as possible... forget everything else, except perhaps MB-174 for strategic reconnaissance and eventually, MB-175 for bombing (but they came too late, so DB-7, Martin 167F and Curtiss H-75 would still be welcome).
Elan Vital
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If we keep the single tail we might as well put the Amiot 340 in production as is when it had performed a PR stunt with Vuillemin rather than redesigning it with an additional gunner and twin tail as the 350, only to produce a dozen in 1940.
We need good airframes ASAP, and the Amiot was fast and better-suited for mass production than the LeO 45, albeit with a somewhat smaller payload. Moreoever unlike the LeO the Amiot's engine shrouds were IIRC far easier to remove for maintenance. This was a major problem for the LeO.
Historically most crews wanted to use twin or triple 7.5 MGs instead of the 20mm. It is surprising that nobody was worried the 20mm might be a bad idea, it should have been experimented with a few aircrafts first, not imposed immediately.
We need good airframes ASAP, and the Amiot was fast and better-suited for mass production than the LeO 45, albeit with a somewhat smaller payload. Moreoever unlike the LeO the Amiot's engine shrouds were IIRC far easier to remove for maintenance. This was a major problem for the LeO.
Historically most crews wanted to use twin or triple 7.5 MGs instead of the 20mm. It is surprising that nobody was worried the 20mm might be a bad idea, it should have been experimented with a few aircrafts first, not imposed immediately.
I've shared my thoughts with the "LN-161 timeline" author DMZ, he kind of agree we should have built a powerful strike force of Potez 63s, per lack of another multi-engine type available in any significant number before the summer 1940 at least.
Keep the three excellent American aircraft (M167F, DB-7 and Curtiss H-75) and do a serious cleanup among French types...
Keep the three excellent American aircraft (M167F, DB-7 and Curtiss H-75) and do a serious cleanup among French types...
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A 20 mm cannon was effective against most WW2 AFVs. The longer the barrel and the faster the muzzle velocity, the more likely it is to puncture armor plate.
Also remember that most AFVs have thick frontal armor, but progressively thinner armor on the sides, rear and roof.
Ergo, a dive bomber is far more likely to kill an AFV than a ground-mounted anti-tank gun firing the same 20 mm ammo.