Nieuport 161 - A Stronger French Air Force in May 1940

[miletus12]

Dec 9, 2021 18:59:43 GMT DMZ said:

And you still not answer my questions. So I assume you have no objection on the fact that MS 406 should have been elimated in regard of its poor performances, lower than expected. And LN 161 should have been ordered after having complied with all requirements. And in absence of evidence of material cause, LN 161 order should have been issued as planned.

Pending the crash reports on both aircraft, neither would have passed review. But that would be an American investigative type review such as nixed the Boeing XF6B or the Curtiss XP-31 Swift I cannot and will not speak for the AdA of 1935-1940. 

[DMZ]

miletus12,
Ok, so you have not evidence LN 161 was responsible for the crash, same as the contemporaries. Thank you.

[miletus12]

Dec 10, 2021 7:13:43 GMT DMZ said:

miletus12 ,
Ok, so you have not evidence LN 161 was responsible for the crash, same as the contemporaries. Thank you.

I think I wrote that the investigators guessed as to the crash cause? We would have to build a copy and fly it with the means and methods they used to test the plane to duplicate what they saw.  A crash post-mortem would tell us a great deal more than it revealed to them, since we would have a superior body of information to let us check for defects we could see in design, and for which we could wind tunnel and or test subscale in flying models.  

You have read this item?

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, 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, Nieuport 160 flew several short times. Consequently, she need some modifications.

In November 1935, Les Ailes noticed 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 very tall fins.



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

My somewhat different interpretation is that the aircraft designers of the LN160-161 were tinkering with the air screw and the vertical stabilizer on the plane constantly during the test and evaluation program, trying to figure out an air flow instability problem that they actually knew existed in the plane. Similar efforts were being applied to the Morane Saulnier (same article) as regards the radiator air cooling circuit fault and engine intake system on that bird at about the same time.

If I had been an off site evaluator, reading these incidents and reports, I would have become alarmed. Two flying turkeys, not ready for demonstration of viability, were competing for an aircraft contract critical for a primary fighter intended for French air defense? No wonder the evaluators were looking at the Bloch 151. 

I assign less criminality to the inspectorate in the matter than the article author does. It seems to me, now, that the choice was between which bird would actually have its mechanical issues and problems solved first, as I read this "nuanced" account.

The Morane got its issues fixed first a year earlier than the LN161. The need was urgent immediate. It won the contract.
.

   

[DMZ]

Dec 10, 2021 16:23:17 GMT miletus12 said:

Yes, I read it and particularly:

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).
Inquiry about the crash having exonerated the fighter, a Nieuport 160 series may be launched."

Dec 10, 2021 16:23:17 GMT miletus12 said:

My somewhat different interpretation is that the aircraft designers were tinkering with the air screw and the vertical stabilizer on the LN161 constantly during the test and evaluation program, trying to figure out an air flow instability problem that they knew existed in the plane.

With due respect, pure speculations.

What about Michel Détroyat stating (same page):

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, that might 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".

[miletus12]

March 1937 Michel Detroyet became a technical expert for SNCAO. Prior to this change in employment, he was associated with Morane Saulnier. For what it is worth, I do believe he was an objective expert when asked the question about the LN161 and the Bloch 150. The question did not address the Morane, though, did it?

[DMZ]

Michel Détroyat was appointed "Pilote expert national" on March 1st, 1937 and became "Inspecteur des matériels volants des SNCA" (Sociétés nationales de construction aéronautique), not only SNCAO (Ouest, mainly former Loire-Nieuport).
Previously, he was the chief pilot of the association Morane-Breguet-Wibault and was involved in the flight tests and tuning of the MS 405.
So he didn't had any specific interest or link to the LN 161, and yes, I think he was an objective expert.

The question didn't address the MS 406 because Air Minister was loocking for an other fighter to replace it or, at least, to complement its production. Bloch MB 151, then Curtiss Hawk H-75 were choosen for that purpose.

[miletus12]

Dec 10, 2021 20:31:35 GMT DMZ said:

The question didn't address the MS 406 because Air Minister was loocking for an other fighter to replace it or, at least, to complement its production. Bloch MB 151, then Curtiss Hawk H-75 were choosen for that purpose.

Hmm. Detroyet tested the Hawk 75, did he not? What was his opinion of the Hawk 75 A-3?

[DMZ]

Michel Détroyat tested the Y1P-36 and was enthousiastic and urged French government to buy the plane despite its very high price and USAAF objection.

According to Drix, it seems he tested operationnal H-75 in December 1939:

Michel Détroyat gave the following time values for a 360° turn (Source : Curtiss Hawk H 75, J. Cuny & G. Beauchamp, Docavia #22) :
12" for the Curtiss H 75,
15" for the Dewoitine 520
18" for the Morane 406.

flashbackplanes.blogspot.com/2016/08/the-curtiss-h-75-very-overestimated.html

In this timeline, Hawk won't be bought due to the earlier starting production of LN 161 and its much better performances than the Morane ones.

[lordroel]

Dec 11, 2021 7:15:16 GMT DMZ said:

Michel Détroyat tested the Y1P-36 and was enthousiastic and urged French government to buy the plane despite its very high price and USAAF objection.

According to Drix, it seems he tested operationnal H-75 in December 1939:

Michel Détroyat gave the following time values for a 360° turn (Source : Curtiss Hawk H 75, J. Cuny & G. Beauchamp, Docavia #22) :
12" for the Curtiss H 75,
15" for the Dewoitine 520
18" for the Morane 406.

flashbackplanes.blogspot.com/2016/08/the-curtiss-h-75-very-overestimated.html

In this timeline, Hawk won't be bought due to the earlier starting production of LN 161 and its much better performances than the Morane ones.

So other countries can buy the Hawk then.

[DMZ]

lordroel ,
As USAAC was reluctant to divert P-36 production to France and direct intervention of Franklin D. Roosevelt was needed to authorize Michel Détroyat to test it, I doubt that other countries could obtain it, at least in a significant quantity, before 1940.

Nevertheless, one can assume that Dutch and Norwegian orders would have been delivered earlier and Norwegian pilots could had opposed a stronger force to the German invasion, including air to ground support. I will think about it.

[lordroel]

So what production rate would the Nieuport 161, how many aircraft would be in service in 1940 and would other production of aircraft suffer from it.

[DMZ]

Possible LN 161 production have been discussed here:
alternate-timelines.com/post/142646

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, Country 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 (+90 %);
- 5 GCs covering Paris and the lower Seine Valley, 150 operational aircraft (+25 %);
- 2 CGs in the southeast facing Italians (+25 %);
- about ten DAT patrols in the contry (+400 %);
- 3 CGs in FNA and 1 CG in Lebanon (with only 34 aircraft each, same as IOTL);
- the GAA and GAM in the Empire (Dakar, Djibouti, Madagascar, two or three in Indochina) (+300 %);
- half a dozen flights into Aéronautique Navale (French Fleet Air Arm), including two for the carrier Béarn (+500 %).

There was a general reserve of 150 aircraft.

(...)

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.

Impact on other planes on the following post:
alternate-timelines.com/post/142654

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.

Morane-Saulnier: 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.

(...)

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!

[lordroel]

Dec 11, 2021 11:20:39 GMT DMZ said:

Possible LN 161 production have been discussed here:
alternate-timelines.com/post/142646

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, Country 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 (+90 %);
- 5 GCs covering Paris and the lower Seine Valley, 150 operational aircraft (+25 %);
- 2 CGs in the southeast facing Italians (+25 %);
- about ten DAT patrols in the contry (+400 %);
- 3 CGs in FNA and 1 CG in Lebanon (with only 34 aircraft each, same as IOTL);
- the GAA and GAM in the Empire (Dakar, Djibouti, Madagascar, two or three in Indochina) (+300 %);
- half a dozen flights into Aéronautique Navale (French Fleet Air Arm), including two for the carrier Béarn (+500 %).

There was a general reserve of 150 aircraft.

(...)

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.

Impact on other planes on the following post:
alternate-timelines.com/post/142654

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.

Morane-Saulnier: 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.

(...)

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!

Was the Nieuport 161 only deployed on Mainland France ore where some also send to Africa ore even Indochina.

[DMZ]

With this production level, I assume all fighters deployed in Empire are LN 163 (Gnome & Rhône air cooled engine and small bomber capability) in replacement of old Potez 25 or D.501 as soon as available in sufficient quantities. Indochina and Djibouti being prioritized due to Japannese or Italian threaths.

[lordroel]

Dec 11, 2021 11:44:28 GMT DMZ said:

With this production level, I assume all fighters deployed in Empire are LN 163 (Gnome & Rhône air cooled engine and small bomber capability) in replacement of old Potez 25 or D.501 as soon as available in sufficient quantities. Indochina and Djibouti being prioritized due to Japannese or Italian threaths.

So how would the Nieuport 161 do against the best Italy and Japan have to trow at it.