Nieuport 161 - A Stronger French Air Force in May 1940

Uchrony Nieuport 161

Aircraft Family Evolutions

If the Nieuport 161 is well known and would certainly have been very close to the production aircraft, one can wonder what would have become of it and which version would have been in service at the time of the German attack.

It is eminently probable that this evolution would have come from the C1 competition of 1936 intended to designate the new standard AdA C1 fighter.

Published on June 15, 1936, the program for this competition called for using the 910 hp Hipano-Suiza 12Y 21 engine with and a maximum speed of at least 500 km/h. It was modified in January 1937 to use the future engine 12Y 51 of 1.100 CV, the required speed was increased to 520 km/h. The takeoff and the landing must be done in 400 m.

The Nieuport design team was highly productive from 1937 to 1939, working on the improvement of the LN 161, the launch of the LN 40 and also producing a prototype for the 1936 C1 competition, the CAO 200.

In our historical frame, the Nieuport design team will, of course, work on an evolution of the Nieuport 161. There is no doubt that the additional 50 HP, linked to some aerodynamic improvements, will enable to achieve the required performances. But the take-off and landing distance will require a redesign of the wing and the addition of more efficient high lift devices than the simple split flaps.

Historically, the SNCAO, to which the Nieuport design team now belongs, developed for this competition the LN 60, later renamed CAO.200. This aircraft, entirely new, had a shorter fuselage than the LN 161, a shorter and more trapezoidal wing, curved flaps and leading edge slats. Making its first flight in January 1939, it reached a speed of 550 km/h in the summer of 1939 and climbed as well as the LN 161-01 with the same 12Y 31 engine but with propulsive exhaust pipes. Unfortunately, the D.520 was already ordered since April and, although a small pre-production run of 12 aircraft launched but not completed before the armistice, it did not have any notable destiny.



SNCAO CAO.200. Collection Philippe Ricco.



SNCAO CAO.200. Collection Jacques Moulin.

Based on the LN 161 airframe - which is the best way to go fast and save production investments - the Nieuport team would have just changed the wings of the aircraft, which would have given birth to the LN 162 which would have looked like this (by gluing the wings of the CAO.200 on the LN 161 from the plans found on the two sites below):

www.airwar.ru/image/idop/fww2/ni161/ni161-1.gif
www.passionair1940.fr/Armee%20de%20l'Air/Apparel/Proto-fighters/CAO-200/Photos/sncao-cao200.png



Possible evolution of the LN 161 into LN 162. © DMZ

Nota bene: the dihedral of the wings is too pronounced on the side view but seems correct on the front view.

One can notice the decrease of the wingspan, the increase of the wing chord, giving a lower relative thickness, and its shape close to the ellipse which are certainly the main causes of the improvement of the aircraft's lift-to-drag ratio. The single radiator scoop under the fuselage possibly decreases somewhat the drag. The canopy would have been refined as on the LN 401.

As work on the prototype was started in early 1937, the aircraft would have been released more than six months earlier than historically and made its maiden flight in the spring of 1938. Even with the 12Y 31 engine from the production LN 161, it would have far exceeded the required performance before the fall. With the 12Y 21, which SNCAO, the supplier of the current standard C1 fighter, would not have lacked, unlike what happened in 1935, it would have easily exceeded 550 km/h. More than enough in any case to be ordered in series instead of the D.520.

This aircraft, finally equipped with the 12Y 45 engine, a 20 mm cannon and four machine guns, as was the D.520 at that time, would have entered service before the summer of 1939, at about the same time as the Bf 109E which would have been largely outclassed, being capable of 560 to 570 km/h only for 5 minutes. If the production from autumn onwards was completely switched to the LN 162, all metropolitan groups would have been equipped with it by May 1940.

It was envisaged to reinforce the wing structure of the LN 161 in order to install two more cannons feed by belts with 120 rounds each. This would have resulted in a very powerfull machine able to destroy any multi-engine bomber in one or two bursts at the cost of probably 10 km/h of top speed.

A navalized version based on the 162, let's call it LN 172, with a tailhook and folding wings would have been produced from autumn 1939 for the Marine Nationale (carrier or land based). A floater version following in the spring of 1940 for battleships and cruisers.

The 12Y 51 (1,000 hp) powered Nieuport, capable of nearly 590 km/h (effective top speed achieved by the Arsenal VG 36 with this engine in May 1940), would have flown at the end of autumn 1939 and arrived in squadrons at the end of summer 1940. The next one with the 12Z engine (more than 1,200 hp) taking off in May 1940 but not delivered in production before the end of the year, would have exceeded 600 km/h.

Other possible evolutions

Paul-Louis Weiller, owner and Chairman of Gnome & Rhône, had an agreement with Marcel Bloch to use exclusively Gnome & Rhône engines on Bloch fighters. Since the Bloch 151 was not mass-produced, wasn't Weiller going to lobby Henry de l'Escaille, General Manager of Loire-Nieuport, to have his fighter re-engined? Wouldn't the Comité du matériel (Equipment Committee) ask for the same to remedy the Hispano-Suiza 12Y engines shortage as it was the case for many other planes? It will also have been considered that the needs of the Empire would certainly have been better addressed by an air-cooled engine (refer to the historical choice of the Koolhoven for that purpose). I would be inclined to think that an LN 163 with a G&R 14N 21 (1,030 hp) and then 14N 49 (1,180 hp) engine should fly by the end of 1938 at the latest, probably mid-1938.



Possible evolution of the LN 162 into LN 163, Gnome & Rhone radial engine. © DMZ.

The introduction of the Nieuport will also induce thoughts on the role of each of the AdA's aircraft. General Vuillemin was in favour of light aircraft, will the availability of the LN 161 lead to the emergence of a single engine assault aircraft armed with a 150 or 225 kg bomb (330 or 496 lb), or even 500 kg (1,100 lb), like the Roussel R-30 for example? Or a single-seater high-altitude photographic reconnaissance aircraft, as the British did in the early months of the war with the Spitfire?

If the assault aircraft came into being, it would most likely be at the beginning of 1939, using the LN 163 to rationalize the use of engines: Hispano-Suiza for the fighter, Gnome and Rhône for the assault bomber. Plan V called for 6 GBAs (Groupes de bombardement d'assaut, Assault Bomber Squadrons) in low-level flight and 6 GBs (Groupes de bombardement) in dive flight with 25 aircraft each, the latter turned into GBAs in semi-dive flight after the LN 411 dive-bomber was rejected for insufficient speed. The VI plan will go up to 16 GBA. The 6 then 8 GBA in semi-dive could have been set up with LN 163 instead of Br 691, that is to say 288 aircraft including the reserve.

The idea of a photographic reconnaissance aircraft without an observer will naturally emerge as historically, the GC I/3 (Groupe de chasse, Fighter Squadron) having been equipped in March 1940 with three photographic D.520 which were never used as such. These aircraft, LN 161R, resulting from the transformation of the first LN 161s replaced by LN 162s in line, could see their birth at the end of autumn 1939 and enter service during winter.

The GRs (Groupes de reconnaissance, Reconnaissance Squadrons) will be equipped with them instead of the Potez Po 63.11 (some being retained for long range reconnaissance later replaced by Bloch MB 174) which will be dedicated to the GAOs (Groupes aériens d'observation, Observation Air Squadrons), and the outdated Mureaux 115-117 will be phased out quicker.

In all the cases, it will be a conversion of LN 161 from the general reserve and not a specific production until the LN 164R which should arrive in the second half of 1940, an aircraft using an engine restoring the power even higher (12Y 49, 910 HP at 5,250 m) still with the long wing of the LN 161 or maybe an extended one, and probably a pressurized cockpit.

Last but not least, should the LN 163 produced, it was certainly that one that would be navalized as the LN 173 (air-cooled engine, bomb-carrying capacity, Hispano-Suiza reserved for the AdA...); for the same reasons, it would be assigned to the GAMs and GAAs (Groupement aérien mixte, groupement aérien autonome, around 6 fighters each) throughout the Empire (Sub-saharian Africa and Indochina).

Uchrony Nieuport 161

Family Sumup

Then i think it can stay here on this board, but just asking.

Uchrony Nieuport 161

Production

Let us get into the thick of things. After having seen that the capacities of the LN 161 would have allowed him to perform as well towards the German aircrafts as the D.520, even to outclass them with the LN 162, let us focus on the possible production of this plane.

As for the technical characteristics, we will use historical facts as a basis, but we have to extrapolate a little here too.

The Needs

Planned Equipment of the Fighers Units (based on documents from the Service historique de la Défense, SHD - index 2B2)

The plan V then the plan VI envisaged a transition from 20 GC (Groupes de chasse, Fighter Squadrons) before the war to 30 (then 50) equipped with 34 aircraft increasing to 40 aircraft (with 2 escadrilles (Flights) each of 12 increasing to three Flights of 10 plus the command aircraft and the reserve).

The Franco-Polish agreements of January 1940 stipulated two Polish GCs to be created.

The production required in 1941 to cope with a monthly loss rate of 35% was 550 C1 per month.

There were two CICs (Centre d'instruction à la chasse, Fighter Training Center): Chartres and Montpellier, each with two flights, and a third school was planned in French North Africa (FNA).

First question: When did the Nieuport get into production?

Some elements lead us to believe that there would have been no more than twelve months between the order and the delivery of the first pre-production aircraft:
1) The delivery of the pre-production aircraft of the LN 40, a single-seat dive bomber whose fuselage and empennage were an evolution of those of the LN 161 and whose wings were much more complex, took place only twelve months after the first flight of the prototype, the order having just been placed; it would then take only two more months to deliver the production aircraft.
2) Loire-Nieuport had access to the Breguet factory in Bouguenais, near Nantes, within SNCA Ouest (Société Nationale de Constructions Aéronautiques, one of the state owned aircraft companies), which was expanded in early 1937 to become one of the largest and most modern factories in France.
3) It was in this factory that the vast majority of the MS 406s were assembled after Morane had demonstrated its inability to mass produce them in its Vélizy plant;
4) The slow start-up of the MS 406 was due to the weakness of the company's industrial resources, on the one hand, and to communication difficulties between Morane-Saulnier and other manufacturers, on the other, as Morane-Saulnier did not provide them with sufficient information.
5) In May 1938, during discussions about a complementary aircraft that would lead to orders for the Bloch 151 and Curtiss H.75, it was estimated that the LN 161 could be delivered in no more than seven months, starting from scratch.

Loire-Nieuport could not have taken longer to produce the LN 161 than the LN 40 in the same Bouguenais factory, even though at the time it was manufacturing the MS 406 and LeO 45 bomber, which had the highest priority.

So with an order in September 1936, the maiden flight of the first production LN 161 would have taken place in September 1937 at the latest.

What would have been the total production of the Nieuport fighter?

I - Production with minimal constraints

It depends on the ramp-up and the maximum production capacity.

The load increase could not have been less than that of the MS 406 or the LN 40. The MS 406 series took six months to reach a monthly production of about 50 aircraft. We can base ourselves on this hypothesis, which is very restrictive for Loire-Nieuport because:
1) The LN 161 was designed to be modular in order to facilitate transport and assembly;
2) MS 406 was particularly long to build, it took more than 16,000 man-hours to build, while the D.520, very comparable structurally to LN 161, took only 6,000 to 8,000.

This means that in March 1938, 90 examples would have been produced (at the same time, the MS 405 was just coming out) and the production would reach thirty to forty fighters per month.

At that time, production would certainly have been constrained by the shortage of various equipment: engine, propeller, landing gear, instruments, radio, armament; it would therefore have stagnated at that level until the end of the year. It is at the beginning of 1939, indeed, that the various blockings were removed and that the aeronautical production took off in France, in particular the one of the MS 406.

We reach 90 + 6 x 35 = 300 aircraft produced in September 1938 during the Sudeten crisis, six GC are equipped.

In September 1939, nearly 1,300 LN 161s were produced and 2,500 in May 1940.

How many aircraft were online?

It is necessary to subtract from these aircraft :
- exports,
- aircraft not yet delivered,
- aircraft destroyed beyond repair in accident.

We can consider that all the aircraft ordered historically by foreign countries will be delivered, i.e. 2 to Switzerland, 12 to Lithuania, 25 to Yugoslavia, 13 to China, 50 to Finland, 45 to Turkey and 25 to Greece. A total of 172 aircraft, to which must be added a few aircraft delivered to Poland (it ordered 160 MS 406s in April 1939, but none were delivered before its invasion). About 200 aircraft were exported, 80 in 1939 (before September, as exports were blocked at that time) and 120 in 1940 (after exports resumed).

An average delay of one month will be taken for the fighter delivery to the unit to take into account the various risks of equipment shortage, armament delay and reception procedure.

We will take into account the average loss of one aircraft per GC and per CIC per month.

In May 1940, it will also be necessary to deduct the aircraft lost in combat during the phoney war, twenty-five historically. Let's assume the higher number of fighters vs the better performance make this number a maximum.

The total number of aircraft delivered to the AdA would therefore have been :
- September 38: 230 aircraft online, in school or in reserve; 144 operational in 6 GC with two flights of 12.
- September 39: 900 aircraft on the battlefront, in school or in reserve; 576 operational in 24 CGs.
- May 1940: 1,440 aircraft online, in school or in reserve; 930 operational in 32 CGs, including two Polish CGs plus a few DAT (Défense aérienne du territoire, Contry Air Defense) patrols and three CICs (40 fighters each).

By this date, most of the GCs had been extanded to three flights of 10 aircraft, plus two for commander and eight in reserve.

This gives in units:
- 21 GCs facing Germany (including the 2 Polish ones), that is 630 operational aircraft;
- 5 GCs covering Paris and the lower Seine Valley, 150 operational aircraft;
- 2 CGs in the southeast facing Italians;
- about ten DAT patrols in the contry;
- 3 CGs in FNA and 1 CG in Lebanon (with only 34 aircraft each);
- the GAA and GAM in the Empire (Dakar, Djibouti, Madagascar, two or three in Indochina);
- half a dozen flights into Aéronautique Navale (French Fleet Air Arm), including two for the carrier Béarn.

There was a general reserve of 150 aircraft.

It should be noted that no transformation was necessary, so all the GCs were operational in May 1940.

II - Historical production

Another approach to determine the production is simply to reallocate to the LN 161-162 those of the MS 405-406 (1,084), D.520 (228, not taking into account the ongoing production) and VG-33 (6 prototypes and a batch of 160 was close to be delivered even only a dozen was completed) plus 14 (difference of the pre-series LN 161 (30) / MS 405 (16)). This method is extremely restrictive with respect to LN 161 because it implies that the time frames of the three production runs are not reduced to one, but has the advantage of ensuring that no additional bottlenecks appear.

There would thus be 1,492 Hispano-Suiza 12Y engine equiped fighters produced by May 10, 1940. If we subtract the 62 exported aircraft (in this case, we are at the minimum export as historicaly), there are 1,430 fighters delivered (considering continuous production, there is no problem with the development of the D.520), meaning, after deducting losses due to accidents and combat, a little more than 1,200 LN 161-162 in service at that date. With the H-75 (118 aircraft online) and MB 15x (198), there would have been more than 1,500 aircraft online, including 70 in CIC.

The answer would probably have been between these two limits. Even in the most restrictive case, there would have been 630 operational aircraft (840 LN 162 online) facing the north-eastern borders and 150 (resp. 200, LN 161-162 and MB 151-152) from Paris to Le Havre. Still with two GCs in the south-east (LN 161 or MB 152), 4 in AFN (Curtiss H.75) and one in Lebanon (LN 161), plus a number of DAT flights (LN 161 or MB 151). In this hypothesis, the Aéronautique Navale flew MB 151-152s.

With a ramp-up only slightly faster than historically (a two-month time lag is enough: 400 more aircraft), the same units would have all been equipped with LN 161-162s.

We will base the further discussion on 21 GCs in front of Germany and 5 more from Paris to Le Havre, each having 40 LN 162, on May 10th. The production being at least 220 aircaft per month. No fighter-bomber in the first approach.

Indeed, and we are comming to it. But before...


Uchrony Nieuport 161

Staffing

Another crucial point is that there would have been about 1,300 aircraft online in units (assuming 25 GC at 40 aircraft and 7 with 34 aircraft plus about ten DAT flights). Would there have been enough pilots and mechanics in May 1940?

Pilots

The Passionair website lists (deduplication done) 896 French fighter pilots as well as 105 Czechoslovakian pilots historically present in units (excluding sub-saharian Africa and Indochina) on May 10, 1940.

www.passionair1940.fr/Armee%20de%20l%27Air/Pilotes/Accueil-Pilotes.htm

If we add the 178 Polish pilots assigned to the French GCs or to the two Polish GCs planned, we come to a total of 1,179 fighter pilots. This gives a deficit of 120 pilots (a little less than 10%) if one has to assign one to each aircraft in unit (in flights or in reserve). That is an average deficit of three or four pilots per group. Nothing dramatic or unmanagable, especially if one prioritizes the GCs of Metropolitan France to the detriment of FNA, as has been the case historically: five GCs with 24 pilots instead of 34 allow one to recover 50 more for the battlefront.

Training

With the abundance of fighters, final training in schools or CICs was not such a bottleneck, and the equipment of the GCs with machines was not a problem from the end of autumn 1939, making it easier to welcome pilots in units at the end of their training.

This added to the fact that the standard fighter is present since the end of 1937, allowing an early training of the pilots, that it will not be replaced and thus will not require the transformation of these pilots (as it was the case historically for the passage from MS 406 to D.520, MB 152 or H-75) and that the creation of an additional CIC (Centre d'Instruction à la Chasse) in FNA, requested by General Mouchard, in charge of training within the AdA, could see the light of day at the beginning of 1940 due to the availability of aircraft, a few more fighter pilots should be available.

Moreover, most of these pilots would have flown the Nieuport early enough to have a perfect mastering of it. Not having to change aircraft, they would have been at the top of their game in May 1940. The integration of the new pilots into the unit, all trained on the same machine, would have been easier.

Even in the worst minimal hypothesis, not retained here, the four GC on H.75 should have been transformed on LN 162, which should have happened in the middle of winter 1939-40; the GC on MB 151-152 were destined to be replaced by MB 155s. The multiplicity of aircraft plus the transformation of the GC H.75 will disrupt the training as historically but earlier and it will be over by May 1940.

Mechanics

Historically, there was a shortage of mechanics within the AdA. The only solution to avoid worsening this shortage with the increase in the number of fighters is to move to three flights per GC, as was planned in the V and VI plans, allowing the pooling of specialties (gunsmiths, electricians, etc.)

Availability will be affected, but the improved reliability (no overheating problems) and the standardization of equipment (Hispano-Suiza 12Y engines only on one type of fighter) will compensate somewhat for the new needs.


Impact on others aiplane production

If mass production of the standard fighter starts six to nine months earlier than that of the MS 406, it will have an effect on the production of other aircraft. A mechanical effect through the monopolization of resources, and a strategic effect through the induced thinking.

The first point mainly affects the engines and propellers that would have been missing from the other aircraft produced. Given the delays in other productions, this would not have become a real problem until the spring of 1939, but it could have contributed to slowing down their production. The Latécoère 298, Loire-Nieuport 401 and Mureaux 117 in particular might have suffered.

Note that the arrival of the LN 163 might have led to a Gnome and Rhône 14N star engine on the LN 40 instead of the Hispano-Suiza 12X. With a much higher speed and carrying capacity, would it have been refused by the AdA?

The allocation of factories would have been completely altered, as the Bouguenais factory would no longer be available to manufacture the LeO 45. But knowing that up to eleven factories had to be mobilized to ensure the ramp up of the MS 406 production, the construction of the LN 161 should, on the opposite, free up industrial capacity elsewhere. With a peak production of 150 aircraft per month, the Morane-Saulnier needed 15,000 workers (16,000 hours per aircraft); with half as many hours needed for the construction of a Nieuport 161 and a monthly production of 200, 5,000 people were freed up for other manufacturing.

At Bloch, SNCASO and SNCAC, the non-manufacture of the MB 151-152 will probably allow a faster start-up of the MB 174-175 twin-engine scout-bomber.

All in all, the rationalization of production will have a beneficial effect on all manufacturing programs. However, equipment bottlenecks will become even more apparent.

There still remains the matter of Morane-Saulnier. It is certain that the lobby in its favor will continue, but it will have no way to regain its momentum. The firm could obtain a consolation prize: an order in mid-1937 for two-seater MS 430 trainers with Salmson Ag9 390 hp engines, which would arrive in mid-1938, almost a year before the North American N.A.A. 57 and 64, for the greater benefit of advanced pilot training. Its successor, the Gnome-and-Rhone 9K-powered MS 435, could fly a little earlier and arrive in school in early 1940.

At the strategic level, it was seen that assault bombing and photographic reconnaissance versions could have been developed. Paradoxically, we are not far from the BCR concept (Bombardement-Combat-Reconnaissance, Bomber-Combat-Scouting, multi-engine, multi-seater Amiot 143, Potez 540...) but with the only aircraft that could satisfy one of its most important requirements (maximum speed): the single-seater fighter. This idea was supported at that time by a few people.

The needs for fighters being covered, there will be no mission in this direction in the U.S.A. It is difficult to foresee then what will be the repercussions on the orders of the other aircraft: Douglass DB-7, Glenn Martin 167F, Chance Vought V 156F... They could take place earlier, the resources being more available, or later because the mission for the search of a fighter was the first and opened the way to the others. In any case, there should not be much difference in these deliveries. In financial terms, however, the fighters represented about a quarter of the U.S. arms bill to France...

One last point: since Curtiss was not overloaded, North American would not have been asked by the British to build the P-40 and would therefore not have been able to offer the XP-51. No Mustang! Quite an impact of this uchrony!


German Reactions

How would the Germans have reacted to this aircraft?

First of all, before the war, the MS 406's announced performance was very close to that of the LN 161, so it is unlikely that it would have made a difference; unless the differences in climb speed attracted attention, but horizontal speed being the watchword of the time, it is unlikely, especially since the difference with the Bf 109E is not huge. After all, the Spitfire was announced as being far superior to the Messerschmitt of the time.

If the production start-up is significantly faster than that of the MS 406, the Germans may be concerned about an aircraft with performance similar to that of the Bf 109D, or even better, and present in similar quantities. In this case, perhaps they will think of favouring the production of fighters from mid-1938. If the Sudeten crisis goes as it has historically, they will quickly return to their initial production plan. But here again, Hurricane and Spitfire production was more worrying than Morane and Bloch production. Moreover, production capacities were clearly in favor of Germany, which had no reason to worry about them.

From the outset of the war, and especially if some thirty examples of the Nieuport 161 were delivered to Poland, they would see that this fighter gave the Poles solid arguments in the air; their small numbers did not, however, allow them to take advantage. They will have to wait a little longer to realize on the western front the important advantage that the LN 162 gives on everything that the LW has to oppose him.

But as Göring quickly forbade his fighters to cross the border, this consciousness will only be very relative and rather late. A reconsideration will be necessary during the winter, but will the pilots be heard?

If they are, there are two solutions: quantity or quality.

The LW may decide to increase the number of JGs to overwhelm the AdA as they did in Poland. What could be the possible increase and what would be the correlative decrease in LW bombers?

It might also favour quality with a more rapid replacement of the Bf 109Ds by "Emil". Here also to the detriment of the production of bombers. And with the same questions. But in the winter of 1939-40, the process is already largely engaged.

In any case, given the four to five month time lag between a possible decision and the attack on the Western Front, the changes will probably be insignificant in terms of the number of bombers and fighters.

At most, the Bf 110s would be present in smaller numbers if it had been proven in Poland that they did not provide a significant speed advantage over the Nieuports, given that they were outclassed in the vertical plane and in maneuverability, but they still had a comfortable margin over the LN 161, and here again, nothing has changed.

The last option was to improve the performance of the Bf 109E, but in such a short time, few concrete results could be brought to the aircraft on line in May 1940.

All in all, and given the short reaction times and inertia of the RLM, there should be no significant change.


French Air Force Organization

Before going further, let's have a look to the AdA organization at the time.

It was quite complex, due to the fight between the Armée de Terre and the young Armée de l'Air created as independant army only in 1934. The compromize was to split the air forces in two components, one reserved to the AdA and one dedicated to big units of Armée de Terre (Forces aériennes de coopération, Cooperation Air Forces). Historically, no less than eight out of twelve Groupes de Chasse facing Germany was under Armée de Terre control, each attached to a specific Army (from North Sea to Switzerland : GC III/1: 7e armée, GC III/2, 1e armée, GC II/2: 9e armée, GC I/5: 2e armée, GC II/5: 3e armée, GC I/2: 4e armée, GC II/4: 5e armée, GC II/7: 8e armée). All the GB and GBA was reserved to AdA while all GR but two and all GAO was attached to an army (GR), an army corps (GAO) or an armored division (GAO). This complexified the missions planning and prevented AdA to make force concentration where needed.

Moreover, the command was modified two times during the "Phoney War" going to a more independant organization in September 1939 to go back to the shared commandment in February 1940.

The frontline was divided in four Zones d'Opérations Aériennes to match with the Groupes d'armées (Army groups):
- ZOAN: Nord, Belgium border, groupe d'armées numéro 1 (GA 1), including BEF
- ZOAE: Est, Luxembourg border to Basse-Alsace, groupe d'armée numéro 2 (GA 2)
- ZOAS: Sud, Haute-Alsace (South of Strasbourg) to Jura until Rhône river (near Geneva), groupe d'armée numéro 3 (GA 3)
- ZOAA: Alpes, Swiss and Italian borders on Alps from Rhône to Menton, groupe d'armées des Alpes (GAA)



Zones d'Opérations Aériennes ZOA. Source PassionAir.

In these zones, the fighters units (Groupes de chasse, GC) was regrouped in Groupements de chasse:
ZOAN
- Groupement 21 from Paris to Le Havre, headquarters in Chantilly
- Groupement 25 (VIIe armée), from Dunkirk to Lille, headquarters in Norrent-Fontes
- Groupement 23 (Ie, XIe and IIe armées), from Valencienne to Luxemburg border, headquarters in Laon
- BEF Air Component between the two groupements, independant from the ZOAN command
ZOAE
- Groupement 22, headquarters in Velaine-en-Hay (IIIe, IVe and Ve armées)
ZOAS
- Groupement 24, headquarters in Chissey (VIIIe armée)



Groupements de chasse. May 10, 1940. In "L'aviation de chasse française en 1939-1940", Lieutenant-colonel Salesse, Éditions Berger-Levrault, 1948

On the rear, there was the Défense Aérienne du Territoire (DAT)

There was no groupement in the ZOAA.


French Victories: the Myth of 1,000 Victories

There is a myth on 1,000 victories in France for the AdA. This is far from reality... It comes from the report made by general d'Harcourt in the summer 1940 that stated AdA fighters shooted down 979 enemy aircraft from September 1939 to June 25 1940, 675 being certain and 244 probable. But this count was aproximate for several reasons. First of all, these are claims and not homologated victories and, as for any other air forces, there are overestimated. Moreover, there is also a lot of double counts due to the method used in the French AdA: a shared victory is counted for one for each pilot, there was an average ratio of 2,5 pilots involved in each kill! Victories on Italian planes was also included in these figures.

This over-claim was not uncommon at that time. Between 10 July and 31 October, during the Battle of Britain, the British claimed 2,698 victories but achieved 1,733, where the Luftwaffe claimed 3,058 victories and achieved only 915.

More realistic figures come from the homologated victories that have been awarded to the AdA's fighter pilots: 245 from May 10th and 62 more before. Arnaud Gillet (in Aéro Journal numéro 15, May 2010) made a precise comparison between the french claims and the german records and found that it matchs quite well in May but becoming largely underestimated in June. German recognized 345 losses to French aircraft (including bombers, reco, DAT and Aéronautique navale to be added to the former) during the Battle of France. We will base our development on these last figures: there was historicaly around 355 victories to the AdA's fighters during the Battle of France. German suffered 26 losses on May 10th and an average of 15 for the following 10 days.

Edit: 355 victories, not 330

Yes, ZOAN is linked to the GA 1 (groupe d'armées numéro un: VIIe armée, BEF, Ire armée, IXe armée and IIe armée) which will advance in Belgium (Operation Dyle-Breda).

Edit: Belgium was sticly neutral at this time to avoid any provocation to Germans and thus forbade entry of Allied troups on its territory, including air forces, even for pursuit of fleeding German aircrafts. This was strictly respected by French air force before May 10. I know that a reco Spitfire was shooted down in spring 1940 over Belgium but it was chased from Germany and tryed to escape his hunter. I assume that RAF also respected Belgium neutrality. Of course, the ZAOE had no such a restriction to fly over Germany and, as Luxembourg has no air force, I suspect his neutrality was not such an issue even if border was fully respected on ground.

Note that IIe armée will stay on the border (Sedan) and should have been rattached to the GA 2 behind the Maginot Line but, for dark political reasons, have been taken away from genéral Prételat. As the general Prételat has played invasion through Ardennes in a kriegspiel in 1938, coming to a similar result of what the Germans achieved in May 1940, it would have been preferable to leave him the defense of his left wing. But this is not the subect of this uchrony...