Potez 631 twin-engined fighter

A beautiful aeroplane !

According to Patrick Marchand (« Les ailes de gloire » n° 9 : Les Potez 63) Potez 631 fighters belonging to AA and Aéronavale shot down 29 German planes, which is not quite negligible. Of course this is unsatisfactory but this relative success was probably the effect of an excellent aircraft design and a powerful armament of 2 cannon under the fuselage (almost the same installation as in the Me 110 but the French cannon was excellent not the German MG FF). Later 4 light MGs were added under the wings of part of the AC. Nevertheless victories could have been much more numerous and losses much lower had this excellent AC been equipped with engines worthy of it. Engines were a permanent problem for the 1940 AA. It would probably have been solved a few months later.

According to Jean Danel and Raymond Cuny in their fabulous book on the French fighter arm (page 182) 199 Potez 631s were on strength (including with the Aéronavale, the French "Fleet Air Arm") on 10 May 1940.
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MS 406 - Juha -

Quote : << But maybe You only want to indicate with you expression that MS 406 was even more underpowered than H75 and so poorer in vertical plane and in acceleration? If so, I agree. >>

- YES, this is exactly what I meant. Nevertheles we should not forget that in the first months of WW II Morane 406s (together with their well-trained pilots) proved superior to the Me 109 D. The engine was not precisely weak (power was 860 ch) but the overall design (including the landing gear legs not locked in flight!) was partly obsolete, the fuselage cross section too big (not unlike the contemporary Hurricane), which means too much drag, the AC too heavy for the engine power.

It was mainly a matter of design : the Arsenal VG-33, which was designed several years later, had a top speed of 560 km/h with the same engine as the MS 406 (top speed 485 but often lower). In profile the VG-33 looked much like a rifle bullet.

Maneuverability is something else : the MS 406, like all French AC, was excellent in this respect. It was not good enough in acceleration and climb rate, as you thought.

The Curtiss' armament was a permanent problem at the time. Originally (in the USA) there were one heavy and one light machine-guns under the engine cowling. The French preferred a standardized armament comprised only of light MGs, which certainly was an error, but probably because the French AF didn't use ANY heavy MG, the French Army only few. Perhaps 3 different categories of fighter armament would have been a bit much for logistics (?). Except the very marginal Caudron CR.714 ("Non bon de guerre", not suited for combat!) all French fighters were SYSTEMATICALLY given as heavy an armament as possible including at least one cannon. So I'm unable to understand the Curtiss exception. Of course they couldn't have a cannon under the cowling but a total of up to 3 heavy MGs and 3 light ones would have been possible - a great improvement in firepower and, last but not least, RANGE. Capitaine Accart really lamented the insufficient firepower and even more the range of his armament. So to speak they had to risk their head (quite literally) to compensate for this when attacking German bombers : they had to come much too close for comfort and quite a few were shot down by the excellent German air-gunners because of that. Great ace Morel was killed after a week (on 18 May) by a bullet in his head, Accart very nearly had the very same fate already on 11 May 1940 (!) and he did get a MG-bullet between his eyes on 1 June while attacking a German bomber once more. He survived, very heavily wounded, only by chance and sheer luck. BEFORE WW II started he had asked for bullet-proof windscreens in due time... This proposal was not criticized but it was never implemented.