Focke Wulf light fighter

[spicmart]

At war's progression Allied aircraft manufacturers went to introduce lighter airframes (of pre-existing designs or lineages) such as the Yak-3, F8F Bearcat, Sea Fury and P-51H.
How could a Focke Wulf light(er) fighter (based on the 190 or not) have looked like?

I think they could have gone the P-51H way. Lighten the internal structure (wing spar etc.), reduce some of the armor, a lighter undercarriage and smaller tail wheel. Maybe a laminar flow wing to make it even faster.
Not sure if a Jumo 213 could be made lighter while keeping reliability.
Armament could be a single MG 213C 20 mm revolver cannon with a cadence of 1400 rpm which would equal about two synchronized MG 151/20 cannons but with vastly better ballistics. MV was 1050 mps compared to the latter's 810 mps.
A bit on the light side maybe but ought be sufficient for fighter vs. fighter combat. Add two MG 131 if needed.
Weight of the MG 213C was 75 kg, assembly weight was 96 kg.
This equals the weight of 4 x 50 cal Browning machine guns.

 

[tomo pauk]

I'll chime in in a more detailed fashion when I return from Germany. But for the starters, I'd avoid heavy brutes like the BMW 801 or the Jumo 213.

BTW - what is the squadron service date expected for the LW Focke Wulf?

 

[spicmart]

US evaluation concluded that a 20 mm round from a Hispano cannon has almost three times the destructive power of a 50 cal round.
Based on that the cadence and MV of an unsynchronized MG 213C should make it worth more than two Hispanos or 6 x M2 50 cal.

As propulsion DB 605 variants might be used or a lighter ALT Jumo 213 as proposed by member mack8 in another thread.
The ring/drum radiator configuration of the Dora was already less draggy than the Me 109's so that one should be kept.
Radiator and overall diameter might be a bit less than the Dora's from which would be a benefit dragwise.

Wing area of Fw 190 (18.3 sqm) or Ta 152C (19.5 sqm) should be kept to lower wing loading.
Standard wing profile seemed good enough. Alternatively a laminar wing profile could be implemented.

 

[Shortround6]

BTW - what is the squadron service date expected for the LW Focke Wulf?

1948 if you want to use the MG 213C cannon?

 

[tomo pauk]

1948 if you want to use the MG 213C cannon?

FWIW, the key premise of an what-if is starting time.

 

[z42]

But for the starters, I'd avoid heavy brutes like the BMW 801 or the Jumo 213.

Why? The other lighter weight options mentioned (F8F, Sea Fury, P-51H, (no idea about yak-3)) got their performance from wrapping a smaller and/or lighter fuselage around the same engine as their predecessors. Why deviate from that evidently successful approach?

As we've been through in several recent threads, bigger planes allow amortizing the weight of crew, armor, guns, radios etc over a bigger engine, making it easier to get good performance. Trying to save by using a smaller engine is very hard to pull off successfully.

 

[tomo pauk]

Why? The other lighter weight options mentioned (F8F, Sea Fury, P-51H, (no idea about yak-3)) got their performance from wrapping a smaller and/or lighter fuselage around the same engine as their predecessors. Why deviate from that evidently successful approach?

Neither of the 3 western aircraft ere lightweight fighters, that OP looks to be about. The 801 was with an abysmal p/w ratio above 5 km, and it was the draggy option, draggiest among the mainstream German engines.
Going with the 213 or 603 will mean a heavy fighter, not a L/W one.

As we've been through in several recent threads, bigger planes allow amortizing the weight of crew, armor, guns, radios etc over a bigger engine, making it easier to get good performance. Trying to save by using a smaller engine is very hard to pull off successfully.

L/W fighter is not a do-all fighter, IMO.

 

[spicmart]

1948 if you want to use the MG 213C cannon?

Was it that late that the design become usable?

Neither of the 3 western aircraft ere lightweight fighters, that OP looks to be about. The 801 was with an abysmal p/w ratio above 5 km, and it was the draggy option, draggiest among the mainstream German engines.
Going with the 213 or 603 will mean a heavy fighter, not a L/W one.



L/W fighter is not a do-all fighter, IMO.

Well, I meant that the Allied superprops were slimmed down compared to their predecessors to optimize performance.
The D-9 was 300 kg heavier than its closest opposition, the Spitfire XIV, and a full ton heavier than the late-war Lavochkin La-7 which was 170 kg lighter than the La-5FN.
The Luftwaffe fighters seemed to get more heavy with time paying tribute to their required ability to fight bombers effectively.
A lightened FW was to compete with the late-war Allied props in dogfighting terms.

The P-51H had an Allison engine. Was it lighter than the Merlin?

 

[Shortround6]

FWIW, the key premise of an what-if is starting time.

The original poster wanted the MG 213 cannon. Wasn't going to happen.

Perhaps a lighter weight airframe was possible in 1943-44, but it needs to use existing guns and as you have pointed out, an existing engine.
The F8F cheated a bit. It not only used 4 guns (in the F8F-1) but it got rid of the two stage supercharger. Helped by new version of the engine with better cooling and a new single stage supercharger which made up some, but not all of the altitude loss.
I haven't looked into which version of engine the Sea Fury got. I tend to doubt it was a 1944 version

 

[spicmart]

The original poster wanted the MG 213 cannon. Wasn't going to happen.

Perhaps a lighter weight airframe was possible in 1943-44, but it needs to use existing guns and as you have pointed out, an existing engine.
The F8F cheated a bit. It not only used 4 guns (in the F8F-1) but it got rid of the two stage supercharger. Helped by new version of the engine with better cooling and a new single stage supercharger which made up some, but not all of the altitude loss.
I haven't looked into which version of engine the Sea Fury got. I tend to doubt it was a 1944 version

Couldn't the MG 213C have been deployed already in 1946?

 

[Shortround6]

Was it that late that the design become usable?

They built 5 guns total (including both calibers ) by the end of the war. I don't know if any of them flew in an aircraft (except as booty)

British, French and Americans' jumped on the data and brought it home. Granted things slowed down when the war ended, Soviets tested an A bomb on August 29, 1949.
Took the British, French and Americans until 1952-53 to get guns into service.

You estimate when the Germans could have done it.

 

[tomo pauk]

Well, I meant that the Allied superprops were slimmed down compared to their predecessors to optimize performance.

Fw 190 was already small, and as light as possible with the 801 in the nose. Granted, we ca start removing the guns and/or armor, but that was not what the superprops were doing.
Going with the 605 in the nose can allow for the 190 to cut both the drag and weight, the wing can be further cut down for extra drag reduction etc.

The D-9 was 300 kg heavier than its closest opposition, the Spitfire XIV, and a full ton heavier than the late-war Lavochkin La-7 which was 170 kg lighter than the La-5FN.

As you can see, lighter engine has it's advantages.

The P-51H had an Allison engine. Was it lighter than the Merlin?

Still the Merlin on the 51H.
The 2-stage V-1710 on the XP-51J was about as heavy as the 2-stage Merlin.

 

[tomo pauk]

The F8F cheated a bit. It not only used 4 guns (in the F8F-1) but it got rid of the two stage supercharger. Helped by new version of the engine with better cooling and a new single stage supercharger which made up some, but not all of the altitude loss.

Vs. the F6F, it also cut down on fuel tankage, it had a smaller fuselage and a smaller wing. All contributing to cutting the weight penalty and drag.
1-stage engine was less draggy due to the lack of intercoolers, and it was lighter.

 

[tomo pauk]

They built 5 guns total (including both calibers ) by the end of the war. I don't know if any of them flew in an aircraft (except as booty)

British, French and Americans' jumped on the data and brought it home. Granted things slowed down when the war ended, Soviets tested an A bomb on August 29, 1949.
Took the British, French and Americans until 1952-53 to get guns into service.

You estimate when the Germans could have done it.

Germans stand a far better chance to have jet engines operative in ww2, than the MG 213.

 

[Shortround6]

Couldn't the MG 213C have been deployed already in 1946?

Maybe with a magic genie.
It is one thing to test a gun on the ground with short belts (see Americans with the .50 cal in 1940 and the gun was over 18 years old at that time)
It is another to work upside in negative Gs, right side up at 3-4 Gs, and at 43 degrees C to - 40 degrees C.
You have to feed the thing, the ammo is about 25% bigger in diameter (the cartridge case) and you are trying to move over twice as many per second through the feed system before you even get to the gun.
Problems they had included high barrel wear, which is not a surprise, this thing used a lot of propellent per shot and coupled with the rate of fire?

 

[spicmart]

Fw 190 was already small, and as light as possible with the 801 in the nose. Granted, we ca start removing the guns and/or armor, but that was not what the superprops were doing.
Going with the 605 in the nose can allow for the 190 to cut both the drag and weight, the wing can be further cut down for extra drag reduction etc.



As you can see, lighter engine has it's advantages.


Still the Merlin on the 51H.
The 2-stage V-1710 on the XP-51J was about as heavy as the 2-stage Merlin.

With a cut-down wing area it would be very similar to a 109, a Macchi MC.205 or the Soviet fighters.
I would keep 18 or 19 sqm to give it improved turn performance, usually not an emphasis of German fighters.

Armor of Allied fighters tend to be a bit lighter.

 

[Tkdog]

Adding lightness is difficult. Add it incorrectly and you are just creating weakness. Given the forced labor and late-stage losing the war syndrome it seems unlikely they could have done it.

Seen various references to the jet program being impacted by quality issues. It really can't be compared to the allied situation at all. Free, motivated, well fed workers who got to vote for their government and whose factory isn't being bombed can do things not available to the Nazis.

 

[GrauGeist]

The Fw190A was smaller than a P-51D - there's really not much you can remove wing or fuselage wise and still have it be airworthy.

 

[tomo pauk]

Adding lightness is difficult. Add it incorrectly and you are just creating weakness. Given the forced labor and late-stage losing the war syndrome it seems unlikely they could have done it.

The Fw190A was smaller than a P-51D - there's really not much you can remove wing or fuselage wise and still have it be airworthy.

As before - engine/powerplant was the heavy brute here, so replace it with DB 605 in order to be able to think about smaller & lighter wing, U/C etc.

Seen various references to the jet program being impacted by quality issues. It really can't be compared to the allied situation at all. Free, motivated, well fed workers who got to vote for their government and whose factory isn't being bombed can do things not available to the Nazis.

German jet engine program was beset with problems. I'd suggest, for an nth time, 1-engined jet fighter design, thus reducing the number of engines and fuel required. Every 20 hours replace the engine.

 

[z42]

As before - engine/powerplant was the heavy brute here, so replace it with DB 605 in order to be able to think about smaller & lighter wing, U/C etc.

Granted, the 605 had pretty good power/weight going for it. However, I don't think that is sufficient to cover the several hundred hp deficit compared to, say, the 213 considering the engine has to carry along the rest of the plane as well, not just itself.

Furthermore, the 213 and 603 had more leeway in the design allowing for higher powered versions in the future, as exemplified by the 213J.

German jet engine program was beset with problems. I'd suggest, for an nth time, 1-engined jet fighter design, thus reducing the number of engines and fuel required. Every 20 hours replace the engine.

Indeed, that's what they would have needed to deploy in volume to have a chance of surviving as an effective fighting force past the '44 big week.

They were working on it, but nothing was ready by the time the war ended. Such as Messerschmitt P.1101 - Wikipedia and Focke-Wulf Ta 183 - Wikipedia