mardi 14 novembre 2017

Nieuport 161 vs Morane 406: The match as described by actual French reviews


Since the May 8, 1945, the defeat of France - as of all its West-Europeans Allies - was attributed mainly to an insufficient development of its armored weapons and of its Air Force.
This last point may be divided in two directions: The first being the relevance of how the Air battles were managed, the second being the aircrafts chosen to equip the "Armée de l'Air". 

Regarding the fighters, France used mainly the Morane-Saulnier 406 fighter ordered in 1936, as were also the Spitfire Mk I and the Hurricane Mk I. The French fighter was credited from performances rather similar to that of the real  Hurricane Mk I: A top speed of 486 kph at 5,000 m against 505 kph for the British fighter. 

The Campaign of France was an extremly painful wake up for French pilots.

A tremendous discrepancy was evidenced between the performance data published and the real knowledge accumulated by the French (and Finnish) fighter pilots who fought with this aircraft between September 1939 and June 1940.

The credibility of these performance data for this fighter (even post-WW II) is absolutely questionable, and the actual French aeronautical reviews (from 1935 to 1939) highlighted unambiguously the lack of speed of the Morane 405 /406 familly.

Ignoring such advices, the MS 406 was preferred to her much more performant contender, the Nieuport 161, unfortunately for the French Armée de l'Air. 
I'm interested by the motivations of the deciders.
  
Method
The French aeronautical reviews from 1920 to the first months of 1939 (period after which a censorship affected all news about the French military aircrafts) were really serious and are interesting to read today. 
I used most Les AilesL’Aéronautique and L’Aéro (a generalist review covering also other sports than Aeronautics), these 3 reviews being available at the Bibliothèque Nationale de France.
Among these reviews, those of the highest level gathered papers written by the actual most famous international experts and were especially dedicated to engineers. 
From the other hand, some short informations - dedicated to inform most the citizen about the more recent French prototypes - were written in a matter of code.
 For example, when a prototype was flying for her maiden flight, the sentence "This first flight was very successful" signified only that none of the problems discovered during that experiment may be solved in a reasonable delay.
However, when a journalist was heavily insisting on only one positive quality for a given aircraft, that might be translated as: "The aircraft manufacturer had not yet solved most of the problems he encountered until now, but this positive quality."


Summary of the French fighter program (July 1934)


Main requirements:
  • A totally enclosed cockpit (imposed).
  • A radio-emitter/receiver (imposed).
  • A retractable landing-gear (heavily suggested).
  • A comprehensive sight on the enemy aircrafts was expected during combats.
  • The maximal speed must exceed 450 kph,
  • The climbing time to   4,000 m was to be better than 6 minutes,
    •                        to   8,000 m                                   15 minutes,
    •                        to 10,000 m                                   20 minutes.
  • A total range of at least 2 hours 30' at 320 kph (800 km) or 3 hours 30' at 230 kph (805 km). So, the combat radius will be about 200 km with 45 minutes of combat. At this time, the fuel consuming of the Hispano-Suiza 12 Y 31 at the cruising run of 1,600 rpm was published as 100 liters per hour, half of the full power one (later, these values were significantly revised upwards).

Two very different design staffs... and approaches


Morane-Saulnier was, during the firsts months of the WW I, the first company to create a single-engined / single-seater fighter (MS type L).

Later, at the end of WW I, most of their production was dedicated to training aircrafts which were unanimously seen as excellent.

Since the end of WW I, the Morane-Saulnier company developed only two fighters using liquid cooled engines:  
  • The MS 325 had, undoubtedly, a modern structure, but she had some unpleasant flying qualities (for unpublished - but obvious - reasons). With a low wing using a real cantilever stressed skin metallic structure, this fighter would have been among the best.


Morane-Saulnier 325 - A well designed metallic fuselage married with the odd masts linking the wings to the fuselage.  The wing were very thick at the landing gear roots: Difficult to avoid abnormal aerodynamic behavior with that... 

  • After this failure, the Morane staff chose to develop a variant of the old MS 225 (issued from the MS 12 of 1927!) fitted with the Hispano-Suiza 12 X engine, the MS 227. This aircraft used the mixed structure and the main layout of the MS A1 of 1917! 

MS 227 C1 - A so vintage look, even in 1934...



















-
None of these fighters were able to exceed 350 kph (20 kph slower than the winners of the contest). Fortunately, none of them were ordered.


The Nieuport company had a completely different history. 

The first leader (Edouard de Nieuport) was a keen of aerial races. 
Very quickly, he designed ultra-light aircrafts (as also an engine) which trusted numerous competitions.
After his death in September 1911 and the death of his brother (1913), his company survived under the wise direction of Gaston Delage, an officer of the French Navy.

During WW I, the company developed several excellent fighters which were able to conquer the mastering of the skies.

After the war, several racers were developed to win the World Air Speed Record: All these aircrafts used liquid-cooled engines.

The most famous one - designed by engineer Marie - was dubbed "le sesquiplan" and established the World Speed Record at 330 kph in 1922, before to establish a new World Speed Record of 375 kph the following year!




Personal document of the author - Nieuport "sesquiplan" (1923) which flew at 375 kph. She was dubbed "sesquiplan" to avoid the word "monoplan", an architecture forbidden by the French Technical Committee of the Aeronautics (STAé)

The Nieuport company designed the Ni-D 42 fighter in 1923 (266 kph) which was the origin of the much more stable Ni-D 62 and the all-metal variant Ni-D 72 before to give the much better Ni-D 82 (280 kph, without supercharger).

The following generation gathered metallic fighters using, at last, supercharged engines as the Nieuport-Delage 121, 122 and Ni-D 125 (400 kph in 1934/35) as also the racers floatplanes designed for the Schneider Cup (Ni-D 450 and 650).


Beginning of the Morane-Saulnier 405

  
The weekly Les Ailes (August 12, 1935) reported the maiden flight of the MS 405 which occurred the August 08, 1935: "Détroyat flew the new Morane fighter (…) which had a retractable landing gearbox. 
This very elegant aircraft was designed to fulfill the new fighter program in which a 450 kph to speed is expected. 
Now, the flights would succeed rapidly."
This short article displayed only and aesthetic satisfaction and remind the need for the new fighter to reach a top speed of at least 450 kph.



Personal document of the author- Mock up of the MS 405 for wind tunnel - The Karman is clearly present. 



  
When the Morane 405-01 prototype flew, the attending journalists understood she was the first modern fighter seen in France, because:
  • The Karman fairings linked perfectly the wings to the fuselage.
  • The totally enclosed cockpit induced a smooth back, streamlining the fuselage.
  • The retractable landing-gear was the first one fitted on a French fighter.
  • The air-screw was the first variable pitch one fitted on a French combat aircraft....
  • She was already fitted with the most powerful engine available in France, the liquid cooled Hispano-Suiza 12 Ycrs of 860 hp, which was, actually, only used by the recce aircraft Mureaux 113, 115 or 117 (the D 510 fighters being always on the assembly line of the Dewoitine plant).
Her layout looked rather similar to that of the Hawker Hurricane, but her less streamlined bow.
Several days later, L’Aéro noticed the famous test pilot Michel Détroyat went to the USA to prepare for the National Air Races he won later - in 1936 - with his Caudron-Renault 460.
Several test flights of the MS 405 were done by his colleagues.

The first week of Octobre 1935, Les Ailes was very keen of the MS 405: 
"Détroyat flew the new Morane fighter a lot of times, succeeding in amazing demonstrations.
This fighter is very impressive, displaying high qualities in term of speed and maneuverability."

To understand the feeling of these observers about the speed of the MS 405 in October 1935 (obviously during flights at very low level), one may remind the fastest aircraft currently seen at the Villacoublay Airbase (10 km from Paris) was the prototype of the Dewoitine 510 (maiden flight: 1934), which had a top speed of only 330 kph at sea level.
In October 1935, the Morane-Saulnier 405 was able to fly - in similar flight conditions - at about 360 kph, 30 kph faster than the D 510!

The aerobatic demonstrated at low level by Michel Détroyat proved clearly his very confidence in the new Morane fighter.

{That appears also as an act of commercial strategy: The Nieuport 160 fighter will first flying the October 5, 1935. 
A daring aerobatics with the more perfected Morane fighter was a good mean to highlight, in front of the deciders, the - provisional - limited agility of the Nieuport fighter! }

Two weeks later, Les Ailes wrote : " The Morane 405 fighter, with the Hispano 12 Ycrs engine, had made a flying run at full speed at low level, the measurement being done by the CEMA [Test Center for Aircrafts and all their on-board Materials]
The top speed at ground level exceed 400 kph. This fighter displayed a good maneuverability.
M. Morane had flown this single-seater which is able to take off and to land as easily as an advanced trainer aircraft."
The ground speed exceeding 400 kph appears nevertheless a little disturbing, at first because it's written after the mention "CEMA measurement". 
Oddly, the real ground speed of the MS 406 / 405 - fitted with the standard HS 12Y31 - never exceeded 380 kph! 
This journalist have been manipulated by some members of the CEMA. 
The focus put again on the maneuverability of the Morane, suggesting, nevertheless, he was not completely fooled.              

In January 1936, Les Ailes published : "Détroyat is completing the perfecting of the new Morane fighter; He displayed us outstanding flight maneuvers.
This fighter should appear as specially dreadful for her contenders; She would enter soon in the CEMA."
Michel Détroyat, as usual, proved again his exceptional piloting skill. 
But, in this short message, there was absolutely no mention to the "exceptional performances" of the Morane 405.
May be, this light decrease of enthusiasm was related to the publication of two excellent pictures of the Hurricane K 5083 on the front page of the weekly with the legend: 500 kph. The significantly lower top speed of the MS 406 could not be accepted by the French fighter pilots.

The January 10, 1936, Les Ailes published that the Minister for Air, general Denain, went to Villacoublay, where, "in spite of storm winds", he examined the demonstrations of the 3 prototype fighters (MS 405, Loire 250, Nieuport 160): "A particular mention for Détroyat, who, flying the Morane 405, give a good demonstration of the qualities of his fighter."

About the same event, L’Aéro published the Morane 405, Loire 250 and Nieuport 160 "were shown in-flight by their respective pilot, Michel Détroyat, Nadot and Surtel, who demonstrated the full range of Aerobatics."
These three pilots succeeded to prove their respective fighters were able to flew safely, even during a storm, and, obviously, that they were very good pilots.

The February 6, 1936, Les Ailes noticed the MS 405 engine was revised before she entered into the CEMA (in order to accomplish her official trials). 

The following week, the same reporter wrote: "Détroyat resume the test flights of the Morane 405 fighter which will be ready to initiate her official trials."
No information leaked about these new tests done by Détroyat...

The Morane 405 entered reallthe CEMA the February 20, 1936.
She flew again with Détroyat when "these flights were stopped after a radiator failure during a dive trial full out; The engine running at full power without cooling was replaced by a new one.
Despite the vapor fumes obliterating the sight of the pilot, Détroyat was able to land safely on the airfield."

L’Aéro gave another detail on this test flight: The radiator fins were blown away by the wind.
One may conclude logically this dive was done full out, but the pilot, watching his trajectory and disturbed by the huge wind noise - 720 km/h (200 mps), twice the speed of the gusts delivered by the deadly Irma storm of September 2017 - was unaware of the Prestone temperature.  

The Mars 9, "the Morane 405, with her repaired engine, resumed her official trials; After the preliminary flights, Détroyat flew several speed tests at different altitudes."
The process of the official tests imposed an analysis of the performances at this step.

But the measured performances were likely significantly lower than expected, so they were not shared with the journalists. 
One preferred to speak about "the successful continuation of the trials regarding the flying qualities of the Morane 405."

L’Aéro of the March 13 noticed : "The M.S. fighter, type 405, Hispano 12 Ygrs, continued her official flying qualities tests.
She succeeded to fly all the aerobatics, three dives full-out, a perfect 2 h 30 flight, including 1 h 20 at 4.000 m at full power.
The military pilots will begin to test her flying qualities."
Such a narrative pose questions: Since October 1935, all the actual readers were perfectly aware of the good maneuverability of the MS 405. 
However, today, we know that a full-power flight lasting 80 minutes was completely impossible for this fighter: From September 03, 1939 to June 25, 1940, none of the French war pilots was able to stay at the maximal speed of the Morane 406 more than a handful of minutes before the engine burned out.

Moreover, as you may discover later in this post, the Morane 405 prototype had a fuel tank of only 320 liters. At full power, the HS 12 Y 31 consumed 280 liters for one hour: So, for 80 minutes, it needed 373 liters, 53 liters more than the total volume of her actual tank! 
Deliberately, L'Aéro introduced us in the fairy tales universe! 

Flying stability tests lasted two more weeks.
By the end of April, Les Ailes noticed "the Morane 405 terminated successfully the flying qualities trials. "  The flying qualities were exactly those expected by the CEMA. But we know perfectly that since the posts written in October 1935 !
In May, the MS 405 "will to be confronted to military experiments."

The May 14Les Ailes summarized some informations about the test flights of the Morane-Saulnier fighter:
"Do you know how many hours of flight the fighter Morane 405 totaled since the beginning of her trials? 80, and more is coming every day! 
To our knowledge, that's the first time a fighter prototype so tough tests.
Incidentally, a modern fighter is not so easy to design: It would be extremely difficult to perfect the Prestone cooling system, and especially the seal rings. During a flight of a CEMA pilot, one leak occurred; Very quickly, the engine burned-out."
[Parenthesis: This last incident is amazing: As you may read previously, the engine was changed just before the MS 405 entered the CEMA and the aircraft was flown by Détroyat.
Today, knowing the operational history of the MS 406 both during the Phoney War and the Campaign of France, we know perfectly how bad the cooling system of that "fighter" was. 
Obviously, there was absolutely no reason the prototype was better cooled! 
Moreover, with the aim of securing a production order, the official report of the CEMA in July 1936 noticed clearly the Morane 405 experienced absolutely no problem of heating! ]
"An other difficulty was to obtain a good variable pitch air-screw: It's said that, in altitude, the engine speed is 300 rpm below its maximum. This allowing us to predict a maximum speed 
of 500 kph once a well adapted air-screw will be fitted on her."

What an odd reasoning! If a fighter cannot reach the maximum speed of her engine, it is because her engine was not sufficiently powerful to overpower her drag. Period. 
OK, a better air-screw might allow a marginal gain of - at best - a dozen of kph. 
However, a speed increase of 57 kph implied a power increase of ~40%. It was not credible without a complete redesign of the fighter aerodynamics! 
At the end of June 1936, the Morane 405 is mentioned again: "The Morane fighter flew back to Cazaux, where she proceeded to new tests. 
One must change her engine before the official tests of performances."
Again, it was necessary to change the "naughty engine", unable to reach the calculated speed!
{At the difference of all her contender, the Morane-Saulnier company seemed not affected by the huge strikes of 1936 - which affected severely the Loire-Nieuport company - no comment! }
The MS 405-01 "consumed" between 3  to 4 Hispano-Suiza 12 Ycrs engine in less than 100 flight hours!
Such an engine being especially reliable (demonstrating more than 900 h of continuous service in French Aéronavale in WW II, testimony of Admiral Thabaud in Icare #61, 1972, L'Aéronavale, p. 82), the CEMA deciders should have been much more cautious about the Morane "fighter"...

Rather the opposite, L’Aéro noticed the French Fighter Selection Committee liked to congratulate the Morane-Saulnier team for the excellence of its work. 
These deciders, fully aware that the best proved top speed of the Morane did not exceed 435 kph (Louis Bonte, Histoire des Essais en Vol, Docavia #3, 1974), preferred an aircraft designed to rejoice the spectators of an air meeting but unable to protect the French troops as also the French future bombers or recce aircrafts which will be operational in less than 18 months... 
A lose-lose situation...

The July 23, 1936, Les Ailes published a photograph of the MS 405, with this legend :
"With Michel Détroyat at the controls, the Morane-Saulnier 405 gave us an extremely brilliant display during the "Fête de l’Air", at Le Bourget Airport. 
Until now, this fighter was quite secret. 
The French Air Ministry still forbids the publishing of her structure and of her exact performances. 
This fighter, which exceed the speed of 480 kph, may be seen as one of the most modern and one of the most successful."
The photograph showed perfectly the retractable radiator, the variable pitch Ratier air-screw (actuated by a tiny secondary one) as also the big bulges on the wings leading-edge fairings of the two drum-fed MAC 34 riffle caliber machine-guns.
The mention of the speed exceeding 480 kph remained and is used still today, even if it is always a very big lie.


At the end of July, the CEMA sent the Morane 405 to the manufacturer for modification. 
The September 4, L’Aéro explained this last work, a long time after the official tests: An increase of the wings-dihedral
Such a modification, signifying the lateral stability of the MS 405 was found wanting, suggests us the Cazaux firing tests were no as good as expected.

None review published the real performances du Morane 405 in 1936: They were only partly published the following year.
Nevertheless, for the Paris Air Show, the Novembre 19, 1936, les Ailes published a rather comprehensive article on the MS 405, officially ordered at 16 examples. 




Personal document of the author - A MS 405 drawing as seen by the aeronautical reviews of 1936-1937. The curious cockpit canopy is very far from the real one, even before the maiden flight. The vertical tail fin is also far from the actual pictures...

General data about the M.S. 405
Wing span                                    11.50 m
Length                                            8.75 m         
Height                                             3.30 m
Wing area                                     18 m²
Powerplant                                 860 hp
Empty weight                          1,776 kg
Take-off weight                       2,240 kg
Wing loading                             122 kg/m²
Weight/power ratio                       2.60 kg/hp
Power/m²                                    47.70 hp/m²
Expected speed                      480 to 500 kph

The yellow highlighted data differed strongly from the ones published later.  

The following year, at the Mars 11, 1937Les Ailes published : "The MORANE-SAULNIER 405 one may agree to be one of the finest modern fighters - and probably the best - is continuing her tests at Villacoublay.
This is the M.S.-405 #2, which is far better than the #1. The pilot is Vonner. 
The aircraft #2 is different from the #1 by some modifications affecting the wings and also the landing-gear; The Hispano-Suiza engine delivering 860 hp was fitted with a reduction gear-box 2/3  [instead of the initial 48/51] which seems to give good results.
At 4.000 m - critical altitude of the engine - the M.S.-405 reached officially a top speed of 443 km/h.
At the same altitude, the #2 would reach 480 kph. This is a significant progress.
From the other hand, it is said this fighter will reach 500 kph when she will be fitted with a new fully automated air-screw."

{Parenthesis : The 443 kph refuted the 480 kph published the July 23, 1936: The real Morane top-speed fell 37 kph too short!
OK, the MS 405-02 reached 483 km/h in 1937, but only after the fitting of a Hispano 12 Y 29 engine delivering 920 hp at 3,600 m (giving her an advantage of 20 kph on the HS 12 Y 31 previously fitted(Source : Le Fanatique de l’Aviation, # 100, Gaston Botquin, Mars 1978, article of Gaston Boquin : Le MS 405 était le meilleur chasseur du Monde en 1937, in Frenchp.31).
The larger air-screw and the new reduction gear-box explained the total gain of 15 kph (from 435 to 450 kph). 
Nevertheless, with the 860 hp Hispano, the top speed never exceed 450 kph.}  

The Octobre 28, 1937Les Ailes added some informations about the MS 405-01 : 
"The MORANE-SAULNIER M.S. 405 #1, was entirely overhauled - an operation which was, in fact, unnecessary despite the 300 flying hours she totaled - will fly again at Villacoublay. 
This prototype will be used for presentations, and for the foreign pilots. She would not be used for parachute launching. 
From the other hand, the series of the MS 405 at Puteaux is very advanced. Eleven of them are now on the line [NB : Only 2 of these 11 fighters entered service in Mars 1938, six months later…], thanks to the modern machine tools purchased by the MS company - it cost one million of FF - among them a fourfold electric planer allowing to process together four ribs for stringers (...). 
It may be recall that the fighters built in the Morane plant have a top speed of 450 kph.
The M.S.405 fitted with Hispano engines having a different reduction gear-box and built in the nationalized plants will reach 480 kph."

[NB: These 2 sentences appeared as the model of the answer used even now by the fans of the famous US bomber Lockheed F 35 JSF: "OK, today our aircraft appears as sluggish, but, tomorrow, you will see what happens..."

Another thing is the ideology appearing in the promises suggested by the minister collaborators: The first batch of Morane fighter would be slow - because they were manufactured by a private company - and the later batch would be much faster because they will be manufactured by a nationalized one.

Actually, despite the promises of the Morane-Saulnier lobbyists about the so-called "exceptional Morane 406", "best fighter in the World", the French people have seen the Wehrmacht occupying France under the insolent domination of their skies by the Luftwaffe.]

"At last, in less than six months, the Morane-Saulnier M.S.420, a refined variant of the preceeding fighters, will fly at 520 kph."
{On the progeny of the Morane 405After the humiliation suffered by the French pilots sent to the 1937 international meeting at Zurich with their D 510, the Morane lobby wanted to trigger their dreams to the new Morane fighter, the MS 420, which was designed for 520 kph. But this aircraft needed twenty months - and not only six - to be seen flying in the air.
She was designated as the MS 450. 
Except for its wings, she was a rather different fighter with an expected top speed of 560 kph with the Hispano-Suiza 12 Y 51 engine delivering 1,000 hp at 3,250 m.
The experimental data were never published, so one may remain skeptical over that last speed with the specified engine.

In December 1937, L’Aéronautique confirmed also the top speed of MS 405 measured in 1936 was only 443 kph
Some details were added about her dive ability: 
"One must notice that, with this modern fighters, the critical dives appeared as stressing for most of the pilots.
The dive begins at 4,500 m following a 30° slope and, with the MS 405, the dive must be maintained during about 30 seconds before the speed was 725 kph (200 m/s).
This speed is to be maintained at least for 500 m (=2.5 seconds).
The engine run increases until 2,800 rpm.
Thanks to the braking of the ailerons axes, no flutter happened until 720 kph."

The Novembre 27, 1938 , the reporter of Les Ailes, sent to the Paris Air Show, wrote: " Although we cannot talk about her performances, it's said that once the new Morane-Saulnier fighter would be fitted with the Hispano engine delivering 1,200 hp, the 600 kph were close at hand."
Such information was regarding the MS 450.
The Hispano-Suiza 12 Z, with 4 valves by cylinder, was really powerful but it was not finished - officially - before March or April 1940 (then, it was successfully flown with the Arsenal VG 39).
Nevertheless, the Wikipedia article in English of the June 3, 2016 said: 
"In 1939, Hispano started prototype deliveries of the new Hispano-Suiza 12Z engine of 969.4 kW (1,300 hp). One was fitted to a modified 410 to create the M.S.450, giving dramatic improvements in performance, especially at altitude. " 
Except the anachronism about the MS 410, which existed only in 1940, quite one year after the MS 450, the Anglo-Saxons writers did not give credence to a MS 450 flying at 560 kph with an engine less powerful than a RR Merlin III! I share completely their distrust
Neither her performances, nor her flying qualities (the take off weight increased, not the wing area, so the wing-loading increased, thus the maneuverability was no more exceptional). 
The dangerous Bf 109 E was actually better known. Joke was over.
The Morane 450 was never ordered....
The D 520 and the VG 33 were ordered in mass production, the CAO 200 and the Dewoitine 551 promised even more. } 



The beginning of the Nieuport 161


The Nieuport 160 fighter flew first by the October 5, 1935 (8 days after the Loire 250 of the same company). 

Les Ailes gave a fair introduction of the new fighter:
" The new fighter Nieuport 160 was flown by Sadi-Lecointe. She is an all-metal aircraft with a low wing and a monocoque fuselage; She has a retractable landing-gear and wing radiators. The engine is a Hispano 12-X. (…) 
Light modifications of the controls are now done on this beautiful fighter." 
The author was reporting about both the Nieuport 160 and her stablemate Loire 250, this one fitted with the Hispano-Suiza 14 AA radial air cooled engine delivering 980 hp.

This report has nothing special:  Adjustments of the controls are normal for the first flight of any newborn aircraft

From the other hand, flying two months after the first flight of the Morane 405, the Nieuport 160 could not trigger the same surprise. Moreover, the Nieuport used of the Hispano-Suiza 12 X engine delivering 690 hp, not the HS 12 Y engine delivering 860 hp. 

In the 1930's France, the engines of all military prototypes were properties of the French government (the aircraft manufacturers were financially unable to bought the engines...), so it is easy to detect a clear will to facilitate the success of the Morane-Saulnier company to obtain the final order! 
So, the perfecting of the Nieuport fighter would necessary cost much more time than those of her Morane contender:
  • The HS 12 Y engine weighting 90 kg more than the 12 X and being 0.15 m longer, the gravity center would be at a different place.
  • The exceeding power by 170 hp implied to modify the cooling system.
The flying qualities should be analyzed again after the installation of the true engine, at least to confirm the design team predictions.

Moreover, like her stablemate Loire 250, the N 160 was fitted with a 2-blades, fixed pitch wooden air-screw, as if the best performances were not in option!

The following week, the Nieuport 160 flew several short times. Consequently, she need some modifications.

In November 1935, Les Ailes noticed the N 160 flew almost every days, and reported: "The Nieuport 160 experienced interesting tail changes: She flew perfectly without her dorsal fin."
Such a sentence was a lot exaggerated, the cut back of the fin regarded only 25% of its area! 
Nevertheless, this report confirms the sentence "the application of a Vellay's theory" that Louis Bonte wrote in his Histoire des Essais en Vol, Docavia #3. The Velay's theory attributed some aspects of the lateral instability to the very tall fins.

This modification, a bit shocking for the reporter who as seen the N 160 flying since the first flight, is the proof that the N 161 was not conceived ab initio with a shallow dorsal fin.

It is also the proof that the CEMA, in which Velay was one of the top deciders, had interfered during the manufacturer tests. 
Moreover, it demonstrated the Nieuport 160 fighter flew very well, only 5 weeks after her maiden flight...

From November 18 to 25, the Nieuport 160 flew a lot of time with MM. Surtel and Nadot at her controls. 
Then, she was sent to the Nieuport plant, in Issy-les-Moulineaux, for important modifications. These changes would affect: 
  • The wind screen, initially made of one piece of plexiglas and very advanced for its times, was vibrating at high speed and, so, forbidding precise firing in aerial combat. The new device would be a faceted one... 
  • To enhance the lateral stability, it was necessary to increase the wing dihedral from 3 degrees.
These works were finished the December 12, 1935.


The test flights were very numerous between January 5 to 25, 1936.

The February 6, 1936, the opinion of the journalist of Les Ailes on the Nieuport was expressed under a good picture of the N 160 : "Here is the Nieuport 160 fighter, with retractable landing-gear and tail-wheel.
The preliminary flights were done with a Hispano-Suiza 12 Xcrs engine delivering only 720 hp; Now, a Hispano "moteur-canon" 12 Y crs, acting a three-blades variable pitch air-screw, will enable a top speed of 480 kph at an altitude of 4,000 m.
The Nieuport 160 is a formidable fighter."
Clearly, the Nieuport fighter began to be appealing for the observers.

The last weeks of February were dedicated to install the Hispano-Suiza 12 Ycrs (860 Cv) engine to achieve, at last, the best possible performances. 
With her 690 hp engine, the N 160 had initially an estimated top speed exceeding 440 kph.
From the data published the 6 February, the top speed of the N 160 (with the 720 hp HS 12 X) may be computed as 452.4 kph. A better speed than the MS 405 which used a much more powerful HS 12 Y engine...

Again, the February 20, Les Ailes insisted: 
"The new NIEUPORT 160 appears now as an outstanding fighter
Her perfecting was greatly facilitated by an intensive work in the new air-tunnel the company possess.
More than 400 polar curves were recorded with the six force components automatic Denis-Gruson balance ".


This fighter, renamed Nieuport 161 (after re-engining), resumed her flights in March 1936.
The April 2, 1936, the reporter of Les Ailes told us : "Again, many flights for the two new fighters, the Loire 250 and the Nieuport 161, by Nadot and Lefèvre.
These two fighters have a very advanced development, they will soon enter the C.E.M.A..
Both fighters will be formidable contenders for the Morane 405."

Clearly, the same reporter of Les Ailes - who, in January 1936, wrote the MS 406 would easily win the French fighter contest - had changed his mind three months later
Three months later, he thought the Nieuport 161 was the best contenderHer performances were clearly above the level of the 1934 program expectations, a fact that none among her contender had achieved, and her maneuverability was good enough. 

{The Loire 250 performed well too, but her fuel tank of only 330 liters was totally insufficient to provide enough fuel for a 1,000 hp engine - about only one hour of flight - imposing either a complete restructuration of the aircraft, or the use of another engine.}




Personal document of the author - The N 161, as seen in 1937 by Les Ailes

The trials of the Nieuport 161-01 lasted during the first half of April and, among them, several firing tests were made on the ground.

The followings weeks were dedicated to flights with several in flight tests of variable-pitch air-screws.

At last, the fighter entered the CEMA by mid-MayUnfortunately for her engineers (as for the French fighter pilots) the Front populaire's strikes begun since the May 11, 1936.

After some flights with the manufacturer pilot, the Nieuport 161 stayed in her hangar at least until the June 22.


{During this strike, the CEMA wasted time and money in testing the Dewoitine D 503, a variant of the obsolete D 500 with a huge frontal radiator, a modified fixed landing-gear, slightly modified wings, increasing her top speed from 365 kph to 375 kph(!). 
Simultaneously, the excellent Spitfire K 5054 was flying at 560 kph, 185 kph faster...}

Nobody among these distinguished officers had detected the early signs of the WW II.

During the last week of June, the CEMA evaluate the N 161 flying stability as good.

The 20 August, after the Nieuport fighter had received "engine modifications" and "having completed all the trials of flying qualities, the N 161 was flown to Cazaux."
The purpose was the in flight firing trials. 

Along a full month, these tests were very successful, according to Nieuport, 1909-1950, Rosenthal et al., Docavia #38: "The N 161 was defined as an excellent firing platform"

Unfortunately, the Septembre 22, 1936, occurred the lethal crash of this fighter.

The report of General de Marancourt (3ème Région Aérienne), after explaining "the fighter was firing on a ground target" (so, obviously, she was flying at low altitude, likely about 200 m AGL), he concluded his short report: "This accident seems not to be attributable to the fighter".

Les Ailes published this never disavowed text:
"A very tragic event occurred, the September 22, at Cazaux, by 10 h. 30 a.m.
One of the best pilots of the Villacoublay trial Center, Captain Coffinet, was accidentally killed while he was performing an aerobatic maneuver. 
The aircraft stalled and entered a spin. Her pilot, despite his very high skill, never recovered  the normal flight conditions."

Doing an aerobatic maneuveat low altitude implies always a high level of risk-taking. 

From Les Ailes, Captain Coffinet, who conducted previously the dive tests of the MS 405 during which a maximum speed of only 725 kph was recorded (to be compared with the 780 kph of the Potez 631 twin engined fighter) may have been surprised by the much heavier load factor induced by the faster speed of the N 161.

{Furthermore, the book Libre Intégral written by the great Swiss aerobatics champion Eric Mueller suggests me, given the tail configuration of the Nieuport fighter, that, during a spin, the best recovering method was to pull the flight column, this helping the action of the rudder to counteract the spin.

Contrarily, the official method of the CEMA pilots was to push the flight column first, because they interpreted the spin as a dangerous stall…}


L'Aéronautique of December 1936 published several excellent technical drawings of the Nieuport 161 and, further, some data and performances about her (see below). 

The journalist evoked the Captain Coffinet's crash and concluded : "The fighter had succeeded almost all the tests (but the performances ones).
The inquiry about the crash having exonerated the fighter, a Nieuport 160 series may be launched."

The same monthly published, one year later, for the 1937 Paris Air Show, some data on the cooling system of the Nieuport: The temperature of the Prestone exiting the engine, remained always below the maximum admissible temperature (120°C), the highest value recorded being 116 °C (full power at an altitude of 4,000 m). 

Such an article was a demonstration that the N 161 was really well cooled when the Morane 406 was not at all.


The April 22, 1937, Les Ailes dedicated a comprehensive paper of André Frachet about the Nieuport 161, few days before the prototype #2 flew for the first time.

He wrote: "The Loire-Nieuport 161 attracted the deciders of the Armée de l’Air by her capabilities.   
It seems difficult to achieve a better result, taking into account the requirements of the program in term of horizontal speed, fire power, maneuverability and visibility.
(…)
The Loire-Nieuport 161 benefits to be made with simple elements made of duralumin sheets of normalized L.2.R...
Before assembling,these spares, tough and unobtrusive, are easy to store and transport."

This paper may have been likely written in 1936, before the Paris Air Show. It contained also the first data on one of the French future fighters.

General data (published by both L’Aéronautique in 1936 and in 1937 by Les Ailes) 

In the 2 reviews, the data printed in blue share identical values. The black printed data have been published only by Les Ailes but the top speed at 4,000 m. 
Wing span                                            11 m
Length                                                    9.565 m
Height                                                     2.950 m
Wing area                                             15 m²
Power, at critical altitude : 1 Hispano-Suiza 12-Ycrs engine of 860 hp at 3,250 m.          
Weight empty                                     1,748 kg
    —    mobile                                       530 kg
    —    take off                                   2,278 kg
Wing loading                                        152 kg/m²
Power loading                                          2.64 kg/hp
Power / area                                          57.30 hp/m²
Top speed
  • at sea level                                398 kph
  • at  2,000 m                                435 kph
  • at  4,000 m                                478 kph (les Ailes)   -  480 kph (l’Aéronautique).
  • at  6,000 m                                470 kph
  • at 10,000 m                               398 kph
  • stall (clean config)                    128 kph
  • landing                                      110 kph
Climb times:
  • to  2,000 m                                2’ 30"
  • to  4,000 m                                4’ 58"
  • to  6,000 m                                7’ 49"
  • to 10,000 m                             20’ 32"
The service ceiling was                   11,250 m (well above all actual fighters)
These data cross-check exactly those published by Arnaud Prudhomme in Air Mag of Avril 2005: Those data traced back to 1936, not to 1937.

The September 16, 1937, in the course of news dedicated to the SNCAO, after considerations about the Loire 70 and 130 flying boats, about the Bloch 210 and the installation of the GR 14 M on the twin engined LN 20 - which never flew - Les Ailes noticed:

" The L.N.-161 [#02] fighter is ready; Soon, she will fly to conclude the official trials initiated by the prototype crashed at Cazaux.  
This aircraft is our fastest fighter: At the gross weight of 2.250 kg, she fly at more than 450 kph and is able to fly 900 km at a cruising speed of 320 kph.  
She need only to complete the firing and the performances trials."

Actually, the Nieuport fighter was known to fly at 480 kph.

Table I: Comparison of the data published in 1936 / 1937


Morane-Saulnier 405 
Nieuport 161
Top speed at 4,000 m 
445 kph
480 kph    + 35 kph
Climb time to 4,000 m
<  6’   (?)
4’ 58"        - 1' 02" 
Service ceiling
9, 000 m (?)
11, 000 m    + 2,000 m
Fuel tank
320 liters
360 liters      + 40 liters
Economic cruising speed
315 kph
350 kph        + 35 kph  
total range
700 km (rather 630 km)
875 km    + 175 kph
Wing area
18 m²
15 m²           -3 m²
Empty weight
1, 775 kg
1,749 kg   ==> - 26 kg
Take off weight
2,240 kg
2,278 kg  ==> + 38 kg
Payload
465 kg
530 kg    ==> + 65 kg
Wing loading
124 kg/m²
152 kg/m²  ==> + 28 kg


From these data, it was obvious the MS 405 could not escort any of the French fast bombers of 1940 or recce aircrafts as the Potez 637 whose cruising speed was as fast as the Morane own top speedHer interception capabilities were worse.


To the contrary, the Nieuport 161 fighter, as she was in 1936, was already able to fulfill all these missions, even in 1940, because she performed better than the Curtiss H 75 (but for the total range).

Yes, the MS 405 was, in 1936, able to made tighter turns than the N 161 at low altitude (up to 4,000 m). However, this advantage disappeared at higher altitudes.



Towards the "Morane 406"

Comparing the structural data of the MS 405 of Les Ailes and L’Aéronautique to the ones published today for the Morane 406, some oddities appear.


Morane 405 

L’Aéronautique,       l’Aéro           les Ailes
 Dec. 1936,           Nov. 36          Nov. 37
Morane 406
Area (m²)
18
         17.10         ==> - 0.9      
Weight (empty - kg)
1,775
     1,890           ==>  + 125 
Weight (take off - kg)
2,240
       2,426       ==> + 186 
Payload  (kg)
465
       536        ==> + 81 
Wing loading  (kg/m²)
124
      142       ==> +18
Weight / Power ratio (kg/hp)
2.60
       2.82       ==> +0.22


The 18 m² area of the MS 405 in 1936 were shared by the 3 reviews. In April 1937, André Frachet, in Les Ailes, highlighted the wing area of the MS 405 was 3 m² larger than the one of the Nieuport 161.

On all the blueprint published by the actual aeronautical reviews, a wing of the Morane 405-01 appeared as a simple trapezium ending with a semi-circular wing tip.

These descriptions were absolutely consistent with the pictures of the flying qualities of this aircraft given by both Louis Bonte and the CEMA: A fighter whose take-off weight was 206 kg lighter than the MS 406 of 1940, was obviously more maneuverable (WL: 124 kg/m²) and may climb substantially faster!
As she was initially, the Morane 405 fighter must have been a tough opponent for the Nieuport 161 during a simulated dog-fight at low altitude (probably not above 4,000 m). 

However, the top speed, climb times and total range of the Nieuport fighter, were out of reach for the Morane.


The imperious weight increase of the MS 406...

Comparing the wing geometry of the MS 405-01 of 1936 with those of the wing of the series Morane 406 of 1939, displays a notable différence: The leading edge of the initial wings was rectilinear from the roots towards the wing tips.
Later, in the MS 406, it affected, since the wing roots, an enhanced swept back, reduced after the roots of the landing gear.  

The published wing area of the MS 406 of 1938 lose 0.90 m² over the published one of the MS 405 of 1936.
Simultaneously, the take off weight increased from 2,240 kg to 2,426 kg (configuration for interception with a max. flight time of 1 h 45") to (at least) 2,500 kg maximum (?).
{In the Wikipedia in different languages, other Take Off Weights are published: They range from 2,420 kg, for English readers, to 2,470 kg for Russian readers, 2,540 kg for German readers and 2,600 kg for the Finnish ones - the more powerful Mörkö Morani  attained 2,787 kg. If the Japanese used a TOW of 2,426 kg, they used a maximum weight of 2,720 kg and, also, they reduced the wing area to 16 m².}

Obviously, the wing loading increased from 124 km/m² to ~145 kg/m².
{The Spitfire K 5054 WL was 107 kg/m², those of the Spitfire Mk I in 1939 was 117 kg/m²}
Amazingly, each wing of the fighters built for French pilots was lightened from 23 kg, but the Swiss ordered prototypes did not retain this lightering.

Logically, the weight of the MS 406 increased:
  • The new reduction gear box and the new propeller (diameter increasing from 2.65 m to 3.0 m) added at least 50 kg (remind: The switch from the D.H. two pitch air-screw to the Rotol constant speed (in 1940), added 100 kg to the Supermarine Spitfire MK Ibis!). 
  • Another undue extra weight issued from the so-called retractable (and always inefficient) cooling system, which needed:
    • A trigger system and a moving system (moving device, gears and rails), 
    • A fairing to steer properly the airflow when retracted ,
      • Some flexible and, obviously, much larger pipes
    • The total weight of such a device may be evaluated at 50 kg. 
    • One half of this extra weight was easy to explain: The absolute need of an extra fuel tank on the MS 406.
      • Knowing the 360 liters tank of the Nieuport 161 weighted - empty - 50 kg, one may estimate the 320 liters tank of the MS 405 might weighted 45 kg. So, the extra 80 liters (or 95 liters ?) fuel tank - empty - would weight about 15 kg
    The empty weight - including these 115 kg - increased from 1,775 kg to 1,890 kg.
    Added to the previous take off weight of 2240 kg, one reach 2355 kg.
    The extra fuel added 60 kg, giving a new take off weight of 2415 kg

    The additional armor of 1939 (~50 kg) counterbalanced the lightering of the wings.

    From the other hand, diminishing the wing area was, since 1913, a classical method to win Air Speed competitions. However, the combination of a smaller wing with an heavier fighter, increased significantly the wing loading which increased to 142 kg. 
    If the handling of the Morane fighter remained excellent, her turning radius was no more so short than previously. 
    This explaining the 18 seconds needed for a 360°, given by Détroyat at the end of 1939, a rather good time, but not as good as was the turn in 16 seconds - at 2,000 m - obtained by Vernhold in 1936.

    So, it is possible to confront the Morane 406 of 1939 and the Nieuport 161 of the beginning of 1938.


    Morane-Saulnier 406 
    Nieuport 161
    Top speed in altitude
    450 kph
    480 kph        +30 kph
    Climb to 4,000 m
    6’ 40"  
             4’ 58"            -1' 42"            
    Service ceiling
    9,300 m
    11,000 m       + 1,700 m
    Fuel tank total
    400 liters
    360 liters         - 40 l       
    Economique Cruising speed 
    315 kph
    350 kph       + 35 kph
    Total range
    650 km
    875 km           +225 km
    Wing area
    17.1 m²
    15 m²            - 2.10 m²
    take off weight
    2,426 kg
      2,445 kg           +19 kg       
    Wing loading
    142  kg/m²
    164 kg/m²          

    Amazingly, like the Morane, the Nieuport 161 was also heavier at the mid 1938!  The empty weight increased from 1749 kg to 1,915 kg. Such a 165 kg extra weight was never explained.

    One explication may be found in the anti-crash pylon situated on the vertical tail.
    This pylon, knowing the distance between the head of the pilot and the tail, must be specially strong. It was likely weighting at least 60 kg to withstand the impact of the tail on the ground.
    One may imagine the fitting of an armor may allow us to add 50 kg, but 55 kg are still missing. 

    The difference between the wing-loading of the two fighters in 1936 was reduced from 25% to 12%, the difference of maneuverability between them became very limited

    The fineness of the Nieuport 161
    Previously, we saw the top speed of the Morane 405-01 slightly enhanced (+15 kph) when the power of the engine was better transmitted to the air-screw. 
    In 1937, using of the HS 12 Y 29 with 925 hp boosted the top speed of the MS 405-02 from ~20 kph.
    The Morane company seemed authorized to use the best available engines!

    At the same time, the Loire-Nieuport company appeared ostracized in term of powerful engine. 
    So, to obtain better performances, the engineers of the company might use only their - real - knowledge in AerodynamicsThey worked a lot on the fineness of their fighter.

    The fineness of an airplane is the ratio lift / drag. Obviously, the lift cannot easily be assessed visually.  
    A fast fighter need always to be devoid of a lot of drag sources.
    The wings are one of the main sources of drag by: 
    • The wing area of the MS 405 was 20 % larger than those of the Nieuport 161.
    • Their cross-section. 
    • Their relative thickness.
    • The profil of the airfoil.
    • The interaction with the fuselage at the roots (Karman fairing...).
    • The vortices created at the wing tips are minimized by:
      • the aspect ratio: 
        • the one of the MS 405 was 6.4,
        • the one of the MS 406, was 6.7, 
        • the one of the Nieuport 161 was 8.1, clearly better
      • the tapering (with the counterpart of more fast reactions near the stall).
    The fuselage contribute to about 30 to 35% for a well designed fighter using a liquid cooled engine (e.g. the series D 520: 31.5% - Docavia #4, Dannel & Cuny, Le Dewoitine D 520). 
    One may enumerate:
    • The fairings of each row of six cylinders merged in one unique block on the dorsal part of the cowling, reducing the amount of parasitic interactions.
    • All the air intakes of the bow (for the oil cooler and for the supercharger) were gathered into an unique one (which was subdivided thereafter).
    • The duct of this air intake was located lower on the bow and it fore part was proeminent, allowing a better air supply, because: 
      • the boundary layer was rejected apart,
      • the air entering the duct was no more issued from the hub of the air-screw but from a more peripheral part region of the propeller. So, the real power of the engine was increased.
    • The fuselage tapering, 
    • The minimization of the parasitic interactions, as, e.g.: 
      • Her retractable tail-wheel.
      • Her cantilever horizontal tail, an innovation which caused two lethal crashes to the Messerschmitt 109 F. 
      • The bow of the Nieuport 161-01, already more streamlined than the one of the MS 405, was much more refined later in the N 161-03.
    • A good surface finish: The Nieuport fuselage was an all-metal monocoque with stressed skin. It had an excellent finish, better and more durable than the Morane with her fabric covered fuselage. 
    • The N 161, alone, followed the empiric variant of the areas rule (i.e. ensuring that all the aerodynamic resistances cannot appear in one unique position on the longitudinal axis of the aircraft).
    • The cooling devices of the series Dewoitine D 520 displayed a drag as large as those of the fuselage! The cooling device of the Morane fighter, completely wrong, ignored  the work of Meredith. It may be credited for a catastrophic drag.
    The fineness of the Nieuport improved from the N 161-01 to the N 161-03 which flew 20 kph faster than the prototype of 1936 with an engine delivering the same power.

    The advances obtained by the Nieuport technical staff were as impressive as those obtained by the one of Dewoitine with the D 520 and the D 550.

    L'Aéronautique, which suggested to ordered the N 161 in the edition dedicated to the Paris Air-Show of 1936, insisted again in 1938.
    They published the details of the temperatures measured in flight - during a climb, during flying at full speed - with the Nieuport fighter: That was also a method to explain how bad was the cooling of the Morane 406. 

    Nevertheless, one must be able to read between the lines! The actual French politician were not able such a reading...

    So, her 496 kph published by A. Prudhomme may necessarily be related to the N 161-03

    Recently, my friend Pierre-Yves Hénin send me a new data on the Nieuport 161. It is an undated flyer published by the OFEMA, the commercial agency linked to the Ministry of the Air to sell French aircrafts (and related materials) to foreign governments.



    Personal document of the author - Nieuport 161-03 - The unique air intake under the reduction gear box allowed a very clean nose. The very complicated exhaust pipes were conceived for flare reduction at night...



    In this flyer, one found the following performances, measured during official trials:

                             N 161-03 Top Speed           difference of speed
                                 by 1,000 m steps              vs the N 161-01
    •          0 m          414 kph                        (Estimated, see below)
    •   1,000 m          432 kph                           + 16 kph
    •   2,000 m          452 kph                           + 17 kph
    •   3,000 m          473 kph                           + 17 kph
    •   4,000 m          496 kph                           + 18 kph 
    •   5,000 m          492 kph                           + 18 kph
    •   6,000 m          488 kph                           + 18 kph
    •   7,000 m          476 kph                           + 18 kph
    •   8,000 m          459 kph                           + 16 kph
    •   9,000 m          443 kph                           + 17 kph
    • 10,000 m          414 kph                           + 16 kph
    • 11,000 m          374 kph                           + 14 kph
    • 11,250 m          339 kph                           + 14 kph

    {Approximation of the speed at sea level  :  The prototype N 161-01 flew at 398 kph at 0 m and 416 kph at 1,000 m: The 1,000 m gain increased the speed of the N 161-01 by 18 kph.
    So, I subtracted this amount from the more recent speed at 1000 m and obtained 414 km/h, a 16 kph gain over the 1936 speed at 0 m, consistent with the other speeds.}


    The climb times of the Nieuport 161-03 were:

                                                           for each 1,000 m            advantage over 

                                                                   step                           the N 161-01
    •   1,000           1' 10"                 1' 10"                                     6"
    •   2,000           2' 15"                 1' 05"                                     9"       
    •   3,000           3' 22"                 1' 07"                                     7"
    •   4,000           4' 29"                 1' 07"                                     7"
    •   5,000           5' 40"                 1' 11"                                     8"
    •   6,000           7' 03"                 1' 23"                                     9"
    •   7,000           8' 43"                 1' 40"                                   12"
    •   8,000          10' 51"                2' 08"                                   14"
    •   9,000          13' 48"                2' 57"                                   19"
    • 10,000          18' 29"                4' 41"                                   32" 
    • 11,000          31' 34"              13' 05"                                   53"

    For the first time, a French fighter was able to satisfy the climb to 10,000 m in less than 19 minutes (as specified by the program).

    The last 1,000 meters were 13' 05", with an average instantaneous speed of 1.27 m/s

    The service ceiling remained at least at 11,000 m. 



    The inexpensive but efficient evolution of the LN 161


    Amazingly, the French aeronautical engineers seemed not interested in the ejector exhaust pipes! 

    Nevertheless,  the Dewoitine D 520-01 was fitted with such device in January 1939, her top speed increasing from 503 kph to 527 km/h. This performance triggered her first order (Danel et Cuny, Le Dewoitine D. 520, Docavia #4). 

    So, it is fully legitimate to think that a Nieuport 161, ordered in June 38, would be fitted with such kind of exhaust pipes in 1939.

    Her top speed, following the chosen configuration, would be:

    A - N 161-03  as in the OFEMA flyer...................................................~500 kph

    B - N 161-03 +  ejector exhaust pipes.................................................  520 kph

    C - N 161-03 in B configuration+ Hispano 12 Y 29 ............................  535 kph

    The A version would be able to reach the first squadrons for the end of March 1939, with very better performances than the actual Hurricane Mk I.

    At the end of 1939, the LN 161 would have been in the B configuration.

    In May 1940, they may have been in the C configuration (the C fuel of 92 octane being available, at last!).

    The decision-makers eliminated the Loire-Nieuport 161 in favor of the MB 151


    The Morane 405 have been unofficially ordered in July 1936, before the end of the Nieuport 161 trials. 

    At the end of the Spring of 1938, owing the extremely weak tempo of the Morane-Saulnier production and the poor performances of the MS 406 , the French Air Force deciders were anxious to redirect the orders towards the Bloch 151 or the Loire-Nieuport 161.

    In May 1938, Michel Détroyat, referent pilot for the Air French Ministry, interviewed by the minister on the flying qualities of the Nieuport 161-03 he have just tested, said
    "The first prototype [Nieuport 161-01] displayed some instability at high angle of attack, at less than 240 kph, which was disturbing during a dog-fight. 
    The new aircraft is improved, the instability appears only at speeds inferior to 200 kph; Above that speed, the fighter is stable."

    During another meeting, Detroyat speaking about the Nieuport 161 : "This fighter is as good as the Morane 406, but she had a bit less efficient controls." 

    The Air Minister, Guy La Chambre, asking him to compare the Nieuport 161 to the Bloch 150, Détroyat answered: 
    "There is no possible comparison between them: The Nieuport 161, very easy to fly, is the only one fighter that could be flown by most of the military pilots".
    All these informations confirmed the very good flying qualities of the Nieuport 161

    Unfortunately, the col. Delaittre, director of the CEMA, denying the Détroyat advice, decided to command the MB 151...


    Aftermath


    The July 21, 1938, Les Ailes reacted to the exclusion of the Nieuport fighter from the a great flight display dubbed the "Fête de l'Air":
    We deeply deplored we cannot see the NIEUPORT-161 fighter maneuvering at the "Fête de l'Air. 
    She is always flying with Lefebvre, of the S.N.C.A. de l'Ouest. What is going on with this fighter?"
    The bitter disappointment of this comment is absolutely exceptional among all the numerous articles of Les Ailes I've read. 
    Moreover, these journalists had fought numerous battles that, sometimes, they lost.

    This time, the refusal to order the N 161 appeared to them as a flagrant injustice and, may be, also, as an early-warning sign of an potential defeat.

    The neglected experimentation!

    In November 1938, the Groupe I/7, first user of the Morane-Saulnier 406, practiced mock combats with the best fighters of the previous generation:
    "In the  combats at medium altitude, the Morane 406 were attacked by Dewoitine 510 or Spad 510. 
    These old fighters demonstrate an indisputable superiority because their superior maneuverability and better climb speed
    These two qualities allowed them to stay just behind the tail of the MS 406 unless they were able to escape, their speed being only marginally faster.  

    As it was the case of similar experiments done in Great Britain with the Boulton Paul Defiant against Hurricane or Spitfire, as it was also the case in Germany for the Messerschmitt Bf 110, the French deciders refused to take into account the very bad results of this experimentation. 

    They refused to switch from the MS 406 to the Loire-Nieuport 161 and accelerated the MS 406 mass production program, then obliterating the one of the Dewoitine 520...


    Analyse : What was the motivation of the deciders?


    Some lobbies ?
    The Morane 405 displayed very good maneuverability. She was backed in the CEMA by lobbyists.
    Why?
    Because, reading earlier aeronautical reviews, it appears that they were overcrowded by the social activity induced by the Morane-Saulnier flying school at Villacoublay where members of the French high society met regularly.  

    Obviously, among these persons, numerous were members of foreign - including enemies - embassies. They had a excellent view on the newest prototypes...

    Obviously again, when a politician wanted learn to fly, he went to Villacoublay and received teaching by Morane-Saulnier pilots who, as normal human being, were not impartial at all.

    A part from that, the Nieuport company had got several orders for fighters since the end of WW I to 1933. 
    Some persons belonging to some contenders wanted to retaliate.


    A touch of misinformation 

    The February 18, 1937, the Germans unveiled the Heinkel 51 biplane fighter. She demonstrated an excellent maneuverability, which was also the main quality of the Arado 68 which succeeded her.
    She was the fighter used in the Spain War to test the relevance of the military theories of the German military deciders. 

    Using highly maneuverable fighters was an entailment for a country which had not trained fighter pilots since 1918.
    Unfortunately, the usual quest for nimble fighter - suggested by the request of a wing-loading of 100 kg/m² in the German contest program - induced the French deciders to chose the most maneuverable fighter.

    They remained blind when the Bf 109 V1 was in demonstration at the opening of the Olympic Games at Berlin in 1936.
    One year later, at Zurich, our D 510 were humiliated not only by the Bf 109 fighters, but also by the Dornier 17 bomber which flew 50 kph faster!
    In a normal Air Force HQ, once known the impossibility for the Morane 406 to obtain the required performances, the Nieuport would have been ordered instead and the mass production would have been launched immediately.
    The men who tested the MS 405 with a much more powerful engine (HS 12 Y 29) in order to hide the truth about her performances, shared an heavy responsibility in the Allied defeat in June 1940.





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