Nieuport 161 - A Stronger French Air Force in May 1940

[DMZ]

miletus12,
As LN 163 is already in service in ROCAF, it remains a good option to continue with it. Despite Claire Lee Chennault efforts, it took one year from the recuitment of pilots and purchase of P-40s that American Volonteers Group was able to fight.

And, once again, I fear you underestimate the Nieuport but, as a French person, I am not objective... Nevertheless, LN 161 had a similar climbing rate than P-40 that was incredibly important in fighting against the agile Japannese fighters. And LN 162-163 would have had similar top speed.

BTW, aren't you talking about the Nakajima Ki-43 Hayabusa Oscar instead of Ki-51 that was not a fighter? It was at least as good as the Zero but didn't enter service before mid-1941.

[lordroel]

Dec 12, 2021 10:13:53 GMT DMZ said:

miletus12,
As LN 163 is already in service in ROCAF, it remains a good option to continue with it. Despite Claire Lee Chennault efforts, it took one year from the recuitment of pilots and purchase of P-40s that American Volonteers Group was able to fight.

And, once again, I fear you underestimate the Nieuport but, as a French person, I am not objective... Nevertheless, LN 161 had a similar climbing rate than P-40 that was incredibly important in fighting against the agile Japannese fighters. And LN 162-163 would have had similar top speed.

BTW, aren't you talking about the Nakajima Ki-43 Hayabusa Oscar instead of Ki-51 that was not a fighter? It was at least as good as the Zero but didn't enter service before mid-1941.

So the ROCAF operates Soviet, American, British, Italian and now French planes.

[575]

Dec 11, 2021 9:09:42 GMT DMZ said:

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.

The Dutch wouldn't have much impact on May 1940 operations as the aircraft was destined for DEI though of course it might influenze numbers of fighters available in the homeland as the D-XXI was originally built for the DEI.

In Norway the Fallschirmjäger might not get on the ground if the H-75's are deployed around Oslo and thus able to concentrate there. The capture of Oslo was a daring go as the Luftwaffe transports began to land and was supported on the ground by already landed Bf-110's. With a stronger fighter opposition this may be avoided making for even more chaos at Aalborg Airfield the coming days thus in some way delay reinforcements for the landed troops in Norway.

3. Norwegian Brigade in the southwest may just put up a fight instead of retreat north and delay the German advance on Oslo and help mobilize the Norwegian Army.

The impact on operations in the West may be neglegible except if Hitler wants another go at Oslo forcing airborne diverted from the attack in the West (Netherlands!)

[stevep]

Dec 11, 2021 20:47:03 GMT DMZ said:

Dec 11, 2021 17:25:20 GMT lordroel said:

So what will the Chinese designation of the Nieuport 161 be and will it not be outdated when it enters full production

With more powerfull engine and new wings, it will have a higher top speed of the Zero and a similar climbing rate. Japanese fighters being better in dog fights as already mentionned. New name to come, be patient.

Dec 11, 2021 18:10:52 GMT stevep said:

I think your missing something here?  Obviously some sort of clash between French and Japanese in the FIC area with a lot of civilian casualties and also air losses.

Oops! There is a missing paragraph in my post... I will complement it.

Dec 11, 2021 18:10:52 GMT stevep said:

A licensing deal with China would help the latter if they could get things set up fully but its also going to make Kunming a high priority target for Japan, although that's in some difficult terrain.

Kunming was a top priority for IJA air service as there was some war industries but the bombing never had significant results IOTL.

  DMZ

  On Kunming I'm thinking more of a ground attack.  Don't think the Japanese took it OTL but if they are having those problems with the 161 and identify Kunming as the production area it could jump quite a way up their priority list.

  Which could ironically reduce the incentive to occupy northern FIC as they would cut the supply route by occupying Kunming - assuming they could do that.  Whether they would seek to occupy FIC later would be a key issue as its so important for a drive south.

  Steve

[miletus12]

Dec 12, 2021 10:13:53 GMT DMZ said:

BTW, aren't you talking about the Nakajima Ki-43 Hayabusa Oscar instead of Ki-51 that was not a fighter? It was at least as good as the Zero but didn't enter service before mid-1941.

The Sonia was, like the Dauntless, designed to dogfight as an added function to its dive bombing role.

[lordroel]

DMZ , with the Nieuport 161 in servile with the French Air Force, then it would mean the Dutch can produce the Koolhoven F.K.58 for the Army Aviation Brigade (Luchtvaartbrigade).



Also how would the Nieuport 161 compare to the Koolhoven F.K.58.

[DMZ]

Dec 12, 2021 10:49:39 GMT lordroel said:

So the ROCAF operates Soviet, American, British, Italian and now French planes.

IOTL, ROCAF ordered Po 630 (I don't remember which model) and MS 406 which were retained in FIC under Japannese pressure. Those planes fought against Japannese planes. ITTL, the earlier availability of the Nieuport permit the delivery of the Chinese order before Japannese threat became unbearable.

Dec 12, 2021 11:24:14 GMT 575 said:

The impact on operations in the West may be neglegible except if Hitler wants another go at Oslo forcing airborne diverted from the attack in the West (Netherlands!)

I doubt Hitler will allow more forces than initially dedicated. He could only delay the transfer of LW forces from Norway to Western front. I also estimate a negligible impact.

Dec 12, 2021 13:00:02 GMT stevep said:

On Kunming I'm thinking more of a ground attack.  Don't think the Japanese took it OTL but if they are having those problems with the 161 and identify Kunming as the production area it could jump quite a way up their priority list.

Kunming was too far away and IOTL, Japannese never was in situation to threat this area in a ground attack. In 1940 Kunming was more than 1,000 km away the nearest Japannese occupation zone.

Dec 12, 2021 13:19:43 GMT miletus12 said:

The Sonia was, like the Dauntless, designed to dogfight as an added function to its dive bombing role.

With 430 km/h top speed and only two 7.7 machine guns foreward firing and one 7.7 rearward-firing, I won't tell it a fighter.

Wikipedia:

The Mitsubishi Ki-51 (Army designation "Type 99 Assault Plane"; Allied nickname "Sonia") was a light bomber/dive bomber in service with the Imperial Japanese Army during World War II. It first flew in mid-1939. Initially deployed against Chinese forces, it proved to be too slow to hold up against the fighter aircraft of the other Allied powers.

www.avionslegendaires.net/avion-militaire/mitsubishi-ki-51-sonia/

Toutefois, les Ki-51 vont réellement découvrir leur infériorité technologique le 1er février 1942, lorsque l’US Navy attaqua les îles Gilbert et Marshall, alors détenues par le Japon. Les Grumman F4F et Brewster F2A américains, bien que théoriquement dépassés, firent un véritable carton sur les rares avions japonais qui eurent le temps de prendre l’air. De nombreux Ki-51 furent perdus à ce moment là. Après cette opération, il devint évident pour Tokyo que ce monomoteur était trop fragile pour s’opposer aux avions de chasse américains.

However, the Ki-51s really discovered their technological inferiority on February 1, 1942, when the US Navy attacked the Gilbert and Marshall Islands, then held by Japan. The American Grumman F4F and Brewster F2A, although theoretically outdated, made a real hit on the few Japanese aircraft that had time to take to the air. Many Ki-51s were lost at that time. After this operation, it became obvious to Tokyo that this single-engine aircraft was too fragile to oppose the American fighters.

www.pilotfriend.com/photo_albums/timeline/ww2/Mitsubishi%20Ki%2051%20Sonia.htm

To meet an Imperial Japanese Army specification of December 1937 for a ground-attack aircraft, which it was suggested could be a development of the Ki-30 light bomber.
(...)
In more intensely contested areas the fairly slow Ki-51s were easy prey for Allied fighters,

Dec 12, 2021 18:09:34 GMT lordroel said:

with the Nieuport 161 in servile with the French Air Force, then it would mean the Dutch can produce the Koolhoven F.K.58 for the Army Aviation Brigade (Luchtvaartbrigade)

French order was 50 F.K.58 but only 18 was ever received by AdA. 36 F.K.58 had been ordered for Luchtvaartbrigade in September 1939, without French production, at least half of this batch and possibly all could have been delivered before May 1940.

Wikipedia:

The F.K.58s that became operational were regarded as superior to the Morane-Saulnier M.S.406, comparable to the Bloch MB.151, but inferior to the Dewoitine D.520 and the latest German fighters.

One can assume it would have been inferior to LN 162-163 despite its very good rate of climb.

[miletus12]

Dec 12, 2021 20:20:49 GMT DMZ said:

Dec 12, 2021 10:49:39 GMT lordroel said:

So the ROCAF operates Soviet, American, British, Italian and now French planes.

IOTL, ROCAF ordered Po 630 (I don't remember which model) and MS 406 which were retained in FIC under Japannese pressure. Those planes fought against Japannese planes. ITTL, the earlier availability of the Nieuport permit the delivery of the Chinese order before Japannese threat became unbearable.

Dec 12, 2021 11:24:14 GMT 575 said:

The impact on operations in the West may be neglegible except if Hitler wants another go at Oslo forcing airborne diverted from the attack in the West (Netherlands!)

I doubt Hitler will allow more forces than initially dedicated. He could only delay the transfer of LW forces from Norway to Western front. I also estimate a negligible impact.

Dec 12, 2021 13:00:02 GMT stevep said:

On Kunming I'm thinking more of a ground attack.  Don't think the Japanese took it OTL but if they are having those problems with the 161 and identify Kunming as the production area it could jump quite a way up their priority list.

Kunming was too far away and IOTL, Japannese never was in situation to threat this area in a ground attack. In 1940 Kunming was more than 1,000 km away the nearest Japannese occupation zone.

Dec 12, 2021 13:19:43 GMT miletus12 said:

The Sonia was, like the Dauntless, designed to dogfight as an added function to its dive bombing role.

With 430 km/h top speed and only two 7.7 machine guns foreward firing and one 7.7 rearward-firing, I won't tell it a fighter.

Wikipedia:

The Mitsubishi Ki-51 (Army designation "Type 99 Assault Plane"; Allied nickname "Sonia") was a light bomber/dive bomber in service with the Imperial Japanese Army during World War II. It first flew in mid-1939. Initially deployed against Chinese forces, it proved to be too slow to hold up against the fighter aircraft of the other Allied powers.

www.avionslegendaires.net/avion-militaire/mitsubishi-ki-51-sonia/

Toutefois, les Ki-51 vont réellement découvrir leur infériorité technologique le 1er février 1942, lorsque l’US Navy attaqua les îles Gilbert et Marshall, alors détenues par le Japon. Les Grumman F4F et Brewster F2A américains, bien que théoriquement dépassés, firent un véritable carton sur les rares avions japonais qui eurent le temps de prendre l’air. De nombreux Ki-51 furent perdus à ce moment là. Après cette opération, il devint évident pour Tokyo que ce monomoteur était trop fragile pour s’opposer aux avions de chasse américains.

However, the Ki-51s really discovered their technological inferiority on February 1, 1942, when the US Navy attacked the Gilbert and Marshall Islands, then held by Japan. The American Grumman F4F and Brewster F2A, although theoretically outdated, made a real hit on the few Japanese aircraft that had time to take to the air. Many Ki-51s were lost at that time. After this operation, it became obvious to Tokyo that this single-engine aircraft was too fragile to oppose the American fighters.

www.pilotfriend.com/photo_albums/timeline/ww2/Mitsubishi%20Ki%2051%20Sonia.htm

To meet an Imperial Japanese Army specification of December 1937 for a ground-attack aircraft, which it was suggested could be a development of the Ki-30 light bomber.
(...)
In more intensely contested areas the fairly slow Ki-51s were easy prey for Allied fighters,

Dec 12, 2021 18:09:34 GMT lordroel said:

with the Nieuport 161 in servile with the French Air Force, then it would mean the Dutch can produce the Koolhoven F.K.58 for the Army Aviation Brigade (Luchtvaartbrigade)

French order was 50 F.K.58 but only 18 was ever received by AdA. 36 F.K.58 had been ordered for Luchtvaartbrigade in September 1939, without French production, at least half of this batch and possibly all could have been delivered before May 1940.

Wikipedia:

The F.K.58s that became operational were regarded as superior to the Morane-Saulnier M.S.406, comparable to the Bloch MB.151, but inferior to the Dewoitine D.520 and the latest German fighters.

One can assume it would have been inferior to LN 162-163 despite its very good rate of climb.

Dauntless as a dog fighter.

On each head-on pass, Swede would stomp the rudder and "skid" his aircraft away from the stream of Japanese cannon shells. Then back into a tight turn as each aircraft came around again.


Throughout the dogfight, the SBD's rear gunner was unable to track his guns due to the extreme G forces.



It is sometimes said that dogfights aren't won, they're lost. Eventually one guy makes a mistake. In this case one of the Zeros didn't turn quite tight enough and Swede was able to get in a shot with his forward firing machine guns. The lightly armored Zero went down in flames.



A second Zero pulls up into the vertical. Swede pulls up after him and manages to get a shot off just before his SBD runs out of airspeed. Two down, one to go.



The last Zero, apparently out of ammunition, comes at him head on in a Kamikaze style attack. Swede stands his plane on its wingtip and the two aircraft actually touch wings as they pass. The ruggedly built SBD kept flying, the Zero did not.



Vejtasa was awarded the Navy Cross and transferred to F4F Wildcat fighters. He later went on to shoot down seven Japanese planes in a single day.

The idea was never to tangle with the enemy fighters, but to use the Dauntless as a reserve second echelon air defense aircraft to go after torpedo planes and dive bombers in the fleet defense role as seen at Coral Sea and Eastern Solomons. 

About the Sonia.

Nevertheless, on 28 July 1944 as an official “observer” with permission to fire his guns in self defence, “Mister Lindbergh”” was flying on escort duty over Ceram Island** when his flight went to assist some P38s in a scrap over the Japanese airstrip on the coast at Amahai. Two experienced Japanese pilots in their rather slow Mitsubishi Ki-51 Sonia light bomber/reconnaissance planes, had out-flown their American attackers who had almost expended their ammunition.



By the time Lindbergh’s flight arrived, one of the Sonias had been shot down before it was able to reach the protection of the airstrip’s anti-aircraft guns, and the other, piloted by Captain Shimada, was heading out to sea trailing smoke. Turning back to put up a fight, Shimada came face to face with Lindbergh.



In his diary Lindbergh wrote: “I start firing as the plane is completing its turn in my direction. I see the tracers and the 20’s find their mark, a hail of shells directly on the target. But he straightens out and flies directly towards me.



“I hold the trigger down and my sight on his engine as we approach head on. My tracers and my 20’s splatter on his plane. We are close, too close, hurtling at each other at more than 500 mph. I pull back on the controls. His plane suddenly zooms upward with extraordinary sharpness.



“I pull back with all the strength I have. Will we hit? His plane, before a slender toy in my sight, looms huge in size. A second passes – two – three – I can see the finning on his engine cylinders. There is a rough jolt of air as he shoots past me.



“By how much did we miss? Ten feet? Probably less than that. There is no time to consider or feel afraid. I am climbing steeply. I bank to the left. No, that will take me into the AA fire above Amahai strip. I reverse to the right. It has all taken seconds.



“My eyes sweep the sky for aircraft. There are only P38s and the plane I just shot down. He is starting down in a wing-over, out of control.”

One is in a lot of trouble in a P-38 when one has to have Charles Lindbergh save one's butt.

The Sonia could dogfight with the best of them. 

[DMZ]

miletus12 ,
www.charleslindbergh.com/wwii/

Two Mitsubishi 51 Sonias, armed, two-place reconnaissance-attack craft, returned from searching for a comrade missing after escorting a convoy of the 35th Division to Sorong. Part of the 73rd Independent Flying Chutai, the Sonias were piloted by the 73rd's C.O. Captain Saburo, Shimada and Sergeant Saneyoshi Yokogi,
(...)
The enemy pilots were clearly veteran;.

As in the numerous stories related in the document you provided, Dauntless as a dog fighter, and called "Strange Dogfights", very skilled pilots could face ennemy with far less performant or even not suited for combat plane.

Or do you call B-17 or Lockheed Hudson fighters?

[miletus12]

Dec 13, 2021 8:32:02 GMT DMZ said:

The enemy pilots were clearly veteran;.

That was true. But the paper mismatch numerically and qualitatively with 8 to 1 odds and between a refined P-38 and a Ki-51 force should have made the issue of Japanese pilot experience a null set. Note that Lindbergh, who was clearly an expert combat pilot in the P-38 since he was an instructor in type who flew missions to teach other American pilots, had to make three turns (and missed) and ended with a high off angle guns pass and still almost was rammed? And he could not have been the only experienced American pilot there?

Clearly the Sonia was an agile and dangerous bird.


If you look at the same citation for other entries, where I pulled the Lindbergh example, you will have your answer about the B-17 and the PV-2 Harpoon which is the correct designation for the Hudson.

The B-17 dogfought. 

As for the Hudson? (Same source.)

A Lockheed Hudson like this one was outmatched by a Zero, let alone nine of them led by Saburo Sakei himself. Not one of the better known aircraft of WWII, a Lockheed Hudson was a twin-engine light bomber originally built for the British. The type proved popular and went on to serve with the United States, Canada and Australia. It had one noteworthy feature - it was exceptionally maneuverable for a twin engine bomber. In July of 1942, a lone Hudson of the Royal Australian Air Force was set upon by a crack squadron of Japanese Zeros, led by legendary ace Saburō Sakai himself. Pilot Officer Warren Cowan turned the Hudson on its wing and into his attackers. In a ten minute dogfight, he used the Lockheed's maneuverability to deny the Zeros a shot. Unfortunately, sometimes your best just isn't enough. Sakai himself was finally able to shoot down the badly outnumbered Hudson. Sakai was so impressed by the pilot's skill that after the war he wrote to the Australian government and recommended he be "posthumously awarded your country's highest military decoration".

The pilot Saburo Sakai was possibly the best pilot the IJN had in the area. 
  

[DMZ]

LN 161 - The Cousin

July 1938 - The LN 40, derived from the ill-fated Ni 140 (1), made its first flight. It is a single-seat light dive bomber, equipped with a 12Xcrs engine and can carry a 225 kg bomb. It takes again the general architecture of Ni 140 but without rear gunner. The tests went well and a pre-production run was ordered, followed by a series of 36 for the French Naval Aviation and another 36 for the French Air Force. A second prototype flew in November and a third in March 1939.

Sharing the same production line as the LN 161, whose fuselage was also derived from, which gave them an undeniable family resemblance, production started very quickly and the first examples were produced in May 1939. The landing tests started immediately on the carrier Bearn and were very satisfactory. The dive brakes, on the other hand, were not efficient and were replaced by the opening of the landing gear, which solved the problem. With a few other minor modifications, it gave birth to the LN 401.

Upon receipt of its first examples, LN 411 without tailhook and without wing folding mechanism, the AdA considers that a speed of 380 km/h was insufficient and "gave" its aircraft to the Marine nationale, minus one which would serve as a basis for a more powerful engine. Powered by a 12Y 45 (920 hp), the LN 402 flew in September 1939 and reached 410 km/h, which was finally enough for the AdA, which ordered it in series to equip four GBAs (Assault Bomber Group); deliveries began in February 1940. In parallel, the LN 42 with new, smaller wings was developed and took off for the first time in April 1940. In May 1940, four GBA equipped with LN 402 and two GBA on Bre.691-693 were operationnal.

In September 1939, at the declaration of war, the Marine had height flights of LN 401-411, two of which (AB1, AB2) were embarked on the Béarn in the F1A flotilla, along with two flights (AC1, AC2) of LN 173, an embarked derivative of the LN 163, whose role was the aircraft carrier air defense as well as having an offensive capability, able to carry a 225 kg bomb, but only for horizontal bombing. The Chance Vought 156F, although faster and with greater autonomy, were not retained because they did not yet have their bomb launcher. There was some discussion of landing the Béarn flotilla, but Admiral Darlan, who had worked for the development of embarked aviation and aircraft carriers, decided in favour of keeping it on board. The Béarn was attached to the "2ème division de ligne", Admiral Godfroy, of the "Escadre de la Méditerranée", composed of the old battleships Bretagne, Provence and Lorraine, which, although modernized, were going at the same speed as the Béarn, as well as of four cruisers, three torpedo boats and a submarine.

After gold convoy missions in Canada, the division was incorporated into Admiral Sir Andrew Cunningham's Force X in Alexandria on May 3rd and participated in exercises with the Mediterranean Fleet mid-May. The Béarn, Lorraine and Provence were sent back to Mers el-Kébir on May 20, where they arrived on May 27 to reinforce the western Mediterranean.

(1) The two prototypes of the LN 140 were victims of accidents, one of which being fatal, which put a stop to its development.

[miletus12]

Dec 16, 2021 14:54:08 GMT DMZ said:

(1) The two prototypes of the LN 140 were victims of accidents, one of which being fatal, which put a stop to its development.

Do you have a source report for the accidents? French or German will be fine. I would want to see the evidence for what was observed in the aircraft as to cause.

[DMZ]

miletus12,
You can find a description of the two accidents in Drix blog:
flashbackplanes.blogspot.com/2015/07/the-loire-nieuport-401-411-fighter.html

The first accident was due to engine overspeed during dive.
The exact cause of the second one doesn't seem to be known.

[miletus12]

Dec 16, 2021 18:21:14 GMT DMZ said:

miletus12 ,
You can find a description of the two accidents in Drix blog:
flashbackplanes.blogspot.com/2015/07/the-loire-nieuport-401-411-fighter.html

The first accident was due to engine overspeed during dive.
The exact cause of the second one doesn't seem to be known.

From the citation...

iThe dive brakes consisted in 2 mobile fairings rotating from 90° around the struts linking the highest part of the fuselage to the wings. When the pilot was facing the target at the good altitude, flying at rather low speed (150 kph), he had trigger the rotation of these dive brakes to reduce the diving speed.

The first diving trial being successful, a new step was open at July 8th, 1935: The launch of a bomb during the dive.

After diving vertically from 5 000 m to 1 000 m in 26 seconds – this giving an average speed of 154 m/s (554 kph), suggesting a very faster terminal speed, just before the pull-out – René Paulhan, the well known pilot, released normally the bomb and pull up the stick at full throttle.

Unexpectedly, the engine stay silent and the trajectory remaining horizontal. After several unsuccessful attempt to make the engine running, at this very moment, the pilot became aware the cockpit canopy exit was too small to allow him to bail out!

The Nieuport 140 was too far from the coast to avoid a ditch on the sea. Fortunately, Paulhan ditched successfully and was rescued by a speed boat with minor injuries.

The cause of the engine collapse was the use of a fixed-pitch air-screw, which allowed an over speed well above the rated limit.

I think the observed cause could be described as over-rev which led to induced manifold vapor lock. (Silent engine.). That plane was doomed due to pilot error.  

{Parenthesis: In all the countries where dive bombing were managed, several fatal crash occurred for various reasons, some might be linked to very high speed, other to problems with the air-screw or to the engine (as above), other to an excessive will of accuracy from the pilots.

Then we come to the second accident.

The May 15, 1936, the pilot Jean Decaux, after the release of the bomb, was unable to pull-out and perished in the Mediterranean Sea. No error was found in the technical data to explain this crash.

There are several possible explanations. Gee lock which imposed load forces the pilot could not physically overcome to move plane control surfaces. Overspeed in the dive producing a separate condition called stall lock where the wings do not bite because of equalized air flow over the wing chord and a dramatic neutralization of lift. The pilot misjudged the altitude and simply had too little air room underneath him to pull out of the dive and thus hit the surface of the earth,

Inevitably, most of those causes would be a combination of mechanical induced conditions and or pilot error. A good description by an eye-witness as in the case of the first crash, would narrow down the speculation. How steep was the dive angle; and did the plane wobble or slide during its fall would tell us a lot. If it wobbled, it would not be the pilot's fault. If it locked up and plunged like a bomb, that is all pilot.

[DMZ]

Thanks to 575, a Christmas tale 

LN 161 - Norway

April 9, 1940 - Operation Weserrübung
The invasion of Denmark and Norway went perfectly except in three points:
- The loss of the Blücher delayed the capture of Oslo and allowed the government, the king and the parliament to escape capture, the resistance was decided;
- At Narvik, the loss of the supply tankers blocked the German destroyers;
- In the air, the Norwegian Curtiss Hawk 75A inflicted significant losses on the Ju 52s carrying paratroopers to Oslo Fornebu airport.

Of the 24 Hawk 75A received a few weeks earlier (1), 21 were operational at Rygge, at the entrance to the Oslo fjord. Warned by the echoes of the fight between the fortress of Oscarsborg and the Blücher, a dozen pilots were able to take to the air at daybreak, while the airfield was being approached by He 111s that had come to bomb it. Without escort, two German bombers were destroyed and little damage was inflicted on the airfield, although two Hawks were destroyed on the ground.

Shortly afterwards, the first waves of Ju 52s bound for Oslo Fornebu were intercepted and seven of them went down. The slow reaction of the Norwegian army did not prevent the Fallschirmjäger from taking the field. But the Norwegian fighters shot down or destroyed several Ju 52 on the ground, prohibiting its use from the middle of the day.

The retreat
The next day, the Bf 110s, now based in Denmark, escorted the bombers and the Rygge airfield became untenable. The Curtiss were evacuated to Gardermoen, north of Oslo. Three days later, faced with the German advance and the threat of the first aircraft based at Fornebu, a new retreat was decided. All the airfields up to Tondheim being occupied or under German fire, the 17 remaining Hawks flew to Rinnleiret, 65 km NE of Trondheim, while the Gladiators equipped with skis operated from Vangsmjøse, a frozen lake 175 km NW of Oslo. However, the proximity of the fjord made them fear a naval intervention and a new move was decided towards Hattfjelldal, 200 km further north, as soon as the ground had been cleared of the snow that still covered it, which was done on the 25th with the help of hundreds of civilian volunteers, as the airmen did not have the help of reindeer in transhumance (2). There will be only nine hunters left in flying condition.

From 17 April onwards, the Curtiss supported the defenders of the Hegra fortress, some ten kilometers from Værnes, making aerial bombardments inoperative. They also opposed with relative success the bombardment of Namsos, but the landed equipment, stored without any protection near the docks, was largely destroyed.

1) OTL, 19 Hawk 75s had been delivered and were being assembled at Kjeller, five being practically in flying condition but without armament and none had been taken into account by the Norwegian Army Aviation Service. Thirty-six others were on order. ITTL, as France didn't order Curtiss H-75, Norway would have received theirs earlier.

2) South of Trondheim, between Andalsnes and Dombåss, Lake Lesjaskog had been chosen as the site for the British Gladiators and snow removal had barely begun when three thousand reindeer appeared. The Lappish driver of the herd agreed, in exchange for a bottle of pure medicinal alcohol, to have the necessary surface trampled on, and within a few hours the field was ready... except that the gasoline was missing.