De Schelde S.21, the Dutch all metal multirole fighter that never was

Would you like to see the De Schelde S.21 ingame?
  • Yes.
  • No.
0 voters
In what techtree would you like to see this aircraft be added in?
  • In a future Dutch/BeNeLux techtree.
  • In the British techtree.
  • In the German techtree.
  • Other (Please explain in the comments).
  • I said “No” in the first question.
0 voters

Hello everyone! Today I’m going to suggest one of the most unique aircraft under construction in the Netherlands just before WW2.


The prototype S.21 still under construction
Source: De Schelde S-21 fighter | Secret Projects Forum

This is the De Schelde S.21!

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Illustration of the S.21 in late 1930’s Dutch “mobilization” colours
Source: RS models 92055 De Schelde

History

Spoiler

The origins of this aircraft start way back in the 1930’s. The Dutch shipbuilding company De Schelde started to struggle due to the economic crisis of the 30’s, so the company decided to branch out into other fields. And so the company started to experiment with aircraft.

The first aircraft made by De Schelde were smaller single seat aircraft. But right from these small beginnings we are able to see a trend De Schelde seemed to stick to for most of their aircraft. That being the push-engine configuration.


De Schelde Scheldemusch (Meaning Schelde Sparrow)
Source: De Schelde Scheldemusch - Wikipedia

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De Schelde Scheldemeeuw (Meaning Schelde Gull)
Source: https://www.reddit.com/r/WeirdWings/comments/bpbyp9/de_schelde_scheldemeeuw_a_tiny_pusher_flying_boat/


In the late 1930’s a bigger aircraft was designed, and took it’s first flight on the 29th of March 1940. This was the De Schelde S.20. This was a four-seat, twin boom, push-engine aircraft. Quite an advanced aircraft for the time.


De Schelde S.20
Source: Modelbrouwers.nl modelbouw • Toon onderwerp - De Schelde S.20


That now takes us to the De Schelde S.21. It’s design was presented to the inspection branch of the Dutch Air Force in late 1938. More about it’s design features futher in this post.

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A wind tunnel model of De Schelde S.21
Source: Modelbrouwers.nl modelbouw • Toon onderwerp - De Schelde S.20

The aircraft was very advanced for the time, but it was recieved very positively by the Air Force. Some small changes were requested regarding weaponry, but those did not face any big challenges to implement. De Schelde proposed to built a prototype at their own risk and cost, and so construction started on the aircraft in 1939.


The S.21 under construction
Source: De Schelde S-21 fighter | Secret Projects Forum


Design

Spoiler

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Blueprint of the S.21
Source: De Schelde S-21 fighter | Secret Projects Forum

The S.21 was made of an all-metal construction, had one pilot and a mid-wing (slightly inverted gull) configuration. It would have been powered by a 1085 hp Daimler Benz DB 600Ga engine, that was mounted in the aircraft in a pusher configuration. In order to get around the propellor at the back, a twin boom configuration was used for the tail of the aircraft, which were connected by a single elevator.

The push-engine configuration also led to the designers giving the aircraft a tricycle landing gear. This had the added benefit of giving the pilot a better view of the ground while taking of or landing. One important thing the De Schelde wanted for this aircraft was for it to be very easy to fly.

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Windtunnel model of the S.21
Source: De Schelde S-21 fighter | Secret Projects Forum

As for the weaponry, the aircraft was going to be (for Dutch standards) very heavily armed. [u]The main weapon was to be a 23 mm Madsen autocannon. While the 23mm Madsen was not in service with the Dutch Airforce, the autocannon had already been tested on the Fokker G.1 Prototype. So the Air Force did show interest into this weapon type.

Futher weapons include four forward firing 7.9 mm FN machine guns, that were located next to the pilot, with two either side. But, there was a fifth 7.9 mm FN machine gun located on the aircraft, this one was mounted inside the engine propellor shaft, and it fired backwards. This fixed machine gun could have been used to scare of enemy aircraft that flew behind it. The pilot could pitch the aircraft up and down and by firing the machine gun it would create a wave of bullets.

Two more 50kg bombs could be carried inside the wing, right where the tail connects up to the wing. Instead of the 50kg bombs, two loads of steel arrows could also be fitted, which were a more WW1 era anti-infantry weapon. But for War Thunder these would ofcourse not be included.


But there is something very unique about the main cannon. It is not actually fixed to the airframe, instead it’s actually on a flexible mounting. The pilot had the ability to fix the gun in a horizontal position (just firing forwards) or it could be fixed at an downwards angle of 25 degrees. By putting the gun downwards the pilot could fly the aircraft above enemy bomber formations and then fire downwards (sort of like the German Schräge Musik, only that fired upwards instead of downwards).

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A model of the S.21 with the gun in the downward position
Source: De Schelde S-21 fighter | Secret Projects Forum

But even more crazy then that, the S.21 was also planned to get an autopilot. Not like the modern day computers that can even automatically land an aircraft. The S.21 was planned with a more simple system that would simply keep the aircraft in level flight. Why was this planned for the aircraft you ask? Well like I said already, the main gun was on a flexible mounting. Instead of fixing the gun in a forward or downward position, the pilot could also just unlock it entirely and aim it just like a gunner on a Bomber could. So the aircraft could be put in autopilot mode, and the pilot could put all his focus on firing the main gun accurately at enemy bomber formations.

All these features would make this aircraft fulfill many different roles, the roles the aircraft would fulfill for the Dutch Air Force were that of a “Aerial defence fighter” and “Fighter-bomber”.


Fate

Spoiler

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The unfinished airframe of the S.21
Source: De Schelde S-21 fighter | Secret Projects Forum

On the 10th of May 1940 Germany invaded the Netherlands, and the S.21 was still under construction. The aircraft was about halfway done, with the airframe being almost completed. But by looking at the photos we have of the unfinished airframe, we can see that things such as the engine were not fitted yet. The engine also being a German one by Daimler Benz was most likely not even delivered yet considering Germany had already started the second world war before invading the Netherlands.

What exactly happend to the aircraft following the German occupation is not exactly clear. On the 15th of December 1941 a commander of the German Wehrmacht stationed in the Netherlands made a report to the minister of the German Air Force where the S.21 was still listed as a “Beuteflugzeug” (Trophy aircraft / captured aircraft). The report detailed a possible test where the airframe would be destroyed.

There is another report from May 1943, where it mentions that the S.21 airframe was hanging of the ceiling in the factory hall of the De Schelde facility. Only for it to be taken away by the Germans later.

What the Germans did with the airframe is not known, but it was most likely destroyed. Sadly putting an end to this very unique aircraft.


Specifications

Spoiler


X-ray view of the S.21
Source: De Schelde S-21 fighter | Secret Projects Forum


Crew: 1 Pilot
Length: 8.5 m
Wingspan: 9 m
Height: 3.5 m
Empty weight: 2,050 kg
Full weight: 2,750 kg
Powerplant: Daimler Benz DB 600Ga (1085 hp)
Propellers: 3-bladed variable-pitch propeller


Maximum speed: 570 km/h
Service ceiling: 9,500 m
Max range: 1,400 km (at 4000 m altitude, and 300 km/h)


Armament
Guns:
1 × 23 mm Madsen autocannon
4 × 7.92 mm FN machine gun (Forward firing)
1 × 7.92 mm FN machine gun (Backward firing)

Bombs:
2 x 50 kg bombs


Ingame

Spoiler

It would be amazing to see this aircraft ingame with all of it’s unique features for the main gun. In order to aim the gun down at 25 degrees, we can use the same key bind you use to activate the German Schräge Musik.

And in order to unlock the gun and fire it freely like a gunner I think it should be implemented exactly like that, you press the change view button and you enter a first person cockpit view where you can aim the gun yourself. Ofcourse when you are in the flying view the gun does return to a fixed position. If it were to be coded exactly like a gunner then the gun will automatically fire everywhere even when you are just flying, so that should not be the case.

Ingame I would love to see this aircraft added to a Dutch or BeNeLux techtree. This is a very unique aircraft that would add a lot of value to a new techtree. It’s unfinished prototype status does make it a better fit as an event vehicle, but that doesn’t take away from it’s value to a Dutch tree.

If a Dutch tree is not an option, then I think there are two other logical options left. That being Britain and Germany.

  • Britain was the closest ally the Dutch had during WW2 so it makes sense to add it there.
  • Germany makes sense because the Netherlands was a big fan of German weaponry and technology.

Let me know what you think in the poll above!

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Illustration of the S.21 in a dive
Source: De Schelde S-21 fighter | Secret Projects Forum

So there you have it! Please make sure to vote in the poll above, and let me know what you think of this cool aircraft!


Extra photos/illustrations

Spoiler

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Source: De Schelde S-21 fighter | Secret Projects Forum

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Source: De Schelde S-21:luchtvaartrevolutie? - HistoriënHistoriën

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Source: De Schelde S-21:luchtvaartrevolutie? - HistoriënHistoriën

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Source: De Schelde S-21:luchtvaartrevolutie? - HistoriënHistoriën


Source: De Schelde S-21 fighter | Secret Projects Forum


Source: De Schelde S-21 fighter | Secret Projects Forum


Source: De Schelde S-21 fighter | Secret Projects Forum


Source: De Schelde S-21 fighter | Secret Projects Forum


Sources

Spoiler

Main sources:

Secondairy sources:

Extra sources:

Photos:


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Source: De Schelde S-21 fighter | Secret Projects Forum

3 Likes

Hmm very interesting, i’m not sure how useful the flexible mounting of the cannon is since it can’t aim upwards, but the backwards firing machine gun looks very cool!
Not sure which one to use with Schräge Musik or in gunner view tho

1 Like

Here’s a Model-build company’s rendition of the three main paint schemes used on the plane, based upon old pictures and descriptions.
RS Models 92055 Netherlands IIWW fighter De Schelde S-21 Schilder-instructies

The first two paint schemes are historical and can be seen in old pictures. The German paint scheme isn’t reported to have been applied and can be considered ‘semi-historical’. It’s more likely the roundels would be whited out instead.

Definitely a funky plane, would like to see in a BeNeLux TT, but personally not in a German one.

1 Like

Wait, the document in your suggestion says it’s a second 23 mm cannon
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The second 23mm gun is very unlikely. The sources I can find for this aircraft have a few things where each source states something else.

The rear-firing fixed gun was only meant to scare away enemy aircraft by firing a stream of bullets and pitching the aircraft up and down to create a wave of bullets. If the gun was a 23mm gun, then it would be very limited in ammunition. It’s not meant to hit anything so it would be a waste of space to use a 23mm cannon there. So a 7.9mm machine gun makes much more sense.

1 Like

shaame