Alt 'day' fighters for Luftwaffe, 1937-45

[Horton229]

Note: Refers to Jumo222

...
So just start the Jumos with 3387 cu.inch(55.5L) displacement and run them at 3000 rpm for 2600hp reliability, while working on the supercharging to keep performance up at higher altitudes

Agree with this. Given the 222 ran in 1939, just "let it be" in terms of >2000hp (still a step up) rather than trying to run before you can walk. I wonder how much improvement you might get from simple learning if you produce hundreds vs. an almost bespoke engine every time.

 

[marathag]

I wonder how much improvement you might get from simple learning if you produce hundreds vs. an almost bespoke engine every time.

I always like to use the example of Dodge making the R-3350. They didn't know aero-engines at all let alone air cooled engines before 1942, but did know about mass production and reliability when they did a partial redesign of the cylinders to add cooling fin area, and a lot for more reliability

 

[cortz#9]

Fw 190 project with the BMW P 8028 engine.
That engine never materialized to the best of my knowledge. It was probably designed around the BMW 801 core, with auxiliary S/C aft the engine, feeding the engine-stage S/C via intercooler in the 'beard' location. In early 1942, Fw calculated the max speed of about 650 km/h above 5.5 km, 680 km/h at 9 km, and 735 km/h at 11 km.

View attachment 801114

Cool! A new line drawing to play with. 😎
It'll need some cleaning up first but will hopefully lead to something cool and alternate.
Maybe on another thread though.

 

[mack8]

Started at 2830 cu.in, then jumped on the higher RPM bandwagon, then more displacement, to 3044 cu.in with lower rpm, then more displacement and more rpm 3387 cu.in.
Then they went back 2830 cu. inches with 3200 rpm, and worked on supercharging in 1943-4

It was still sort of like three V-8s set in radial fashion, which had never worked well, as when both Wright and Curtiss tried that format in the early '30s.
The French may have had it worked out right, with the SNCM 130, another 24 cylinder effort of 2931 cubic inches for 1800hp@3200rpm, but 1940 ended that effort.

So just start the Jumos with 3387 cu.inch(55.5L) displacement and run them at 3000 rpm for 2600hp reliability, while working on the supercharging to keep performance up at higher altitudes

I would go even more conservative, stick with the 2900 rpm setting, whatever HP in the region of 2400-2500HP would be very useful, hell even a 2200-2300 HP jumo-222 would be most useful.

And perhaps same for the Jumo-213, i would copy what DB did with the DB-605 and increase capacity to 37,4 litre like the latter Jumo-213J model, and limit the rpm to whatever rating necessary to give the same 1750HP (2800-2900 rpm?), this 300rpm less would reduce stress on the engine and perhaps need for an extensive redesign and demand for the highest quality metals which were in short supply. Maybe it would be ready earlier.

 

[mack8]

And just to coment on a pet peeve of mine, that huge 14,4 or 14,8 m wing on Ta-152H is excessive and likely a hindrance at lower altitudes, probably better to just stick with the 11 m wing, or increase the span but not that much, there was at some point a 12,20m wing tested, so better to go with that, for a more balanced all-around fighter both high and low, plus a lower drag since the wing is smaller.

 

[Nell_Lucifer]

And just to coment on a pet peeve of mine, that huge 14,4 or 14,8 m wing on Ta-152H is excessive and likely a hindrance at lower altitudes, probably better to just stick with the 11 m wing, or increase the span but not that much, there was at some point a 12,20m wing tested, so better to go with that, for a more balanced all-around fighter both high and low, plus a lower drag since the wing is smaller.

I think Kurt Tank said that the Ta 152H had adequate to good performance even at low altitude, being almost as maneuverable as it was at the high altitude it was designed for.

 

[tomo pauk]

And just to coment on a pet peeve of mine, that huge 14,4 or 14,8 m wing on Ta-152H is excessive and likely a hindrance at lower altitudes, probably better to just stick with the 11 m wing, or increase the span but not that much, there was at some point a 12,20m wing tested, so better to go with that, for a more balanced all-around fighter both high and low, plus a lower drag since the wing is smaller.

Perhaps the biggest flaw of the Ta-152 (any version) was that it was too late to matter?

 

[marathag]

I think Kurt Tank said that the Ta 152H had adequate to good performance even at low altitude, being almost as maneuverable as it was at the high altitude it was designed for.

'Adequate' and 'Almost' are great weasel words

But it's physics, higher aspect wings will have a worse roll rate than lower ones

 

[mack8]

Perhaps the biggest flaw of the Ta-152 (any version) was that it was too late to matter?

For the purpose of this ATL, how early could the two-stage DB-603L or Jumo-213E be brought forward to power the Ta-152B/C/H models? Was it the apearance of the Spitfire Mk IX and Merlin-60 engines that spurred the development of the 603L and 213E or was it independent and/or predating it? Single stage variants should just power regular Fw-190s which in this ATL is inline powered from the start anyway. Would a working Jumo-222 in whatever form be any good for a Ta-152 variant performance wise?

 

[tomo pauk]

For the purpose of this ATL, how early could the two-stage DB-603L or Jumo-213E be brought forward to power the Ta-152B/C/H models? Was it the apearance of the Spitfire Mk IX and Merlin-60 engines that spurred the development of the 603L and 213E or was it independent and/or predating it?

Merlin 60 series was probably a revelation for the Germans, being a simple, single-shaft device, an easy addition to an existing engine line, intercooled, and with very much improved altitude power (doh). German experiments were much more elaborate, and still failed to bear the fruit (possibly also due to RLM/LW being undecisive? that, combined with other problems the German aero engines had at the time, was probably not conductive to a jump on the opportunity?). Jumo 213 was also a fairly new engine on itself in 1943.
Germans were aware of the 2-stage Merlin's S/C via open press articles by winter of 1942/43.
If RLM/LW makes a firm requirement towards the similar (or same) device to be installed on current German V12s by early 1943, my guess is that by early 1944 LW fighters would've been flying with 2-stage supercharged engines.

Single stage variants should just power regular Fw-190s which in this ATL is inline powered from the start anyway.

Fw 190 ... deserves the 2-stage S/Ced engine, too It should out-pace and out-climb the Ta 152 that is powered by same engine type.

Would a working Jumo-222 in whatever form be any good for a Ta-152 variant performance wise?

Why not? Appeal of 2000 HP engines was not without substance.

 

[Katzman]

From Luft'46 http://www.luft46.com/
This Daimler Benz aircraft project was basically designed around an engine that was being developed at that time. The Daimler Benz Jäger (not its official name) was of a conventional layout with the exception of the propellers location. The engine was mounted in the fuselage nose, with an annular radiator in front. The wings were unswept and exhibited no dihedral and were mounted below the fuselage. The tail was of a conventional design, with its single fin and rudder. Because of the propellers arrangement, a tricycle landing gear had to be used. A single pilot sat in the cockpit that was located towards the rear, just ahead of the contrarotating propellers.
Where the Daimler Benz Jäger differed from most aircraft was its unusual propeller placement. The Daimler Benz DB 609 development began in September 1942, and it was to be an in-line, 16 cylinder injection-type aircraft engine. It was to develop 2700 horsepower, although this could be increased in later version to 3400 horsepower. Allowance was made for fitting a four-stage supercharger, and with its inverted V design, the DB 609 would have been ideal for a large caliber cannon installation, such as the MK 103, MK 108 or MK 212 cannons.
Although a mockup of the forward fuselage was built (as far back as the propeller location), and because of this engine's long development time (actual delivery wasn't schduled to begin until April 1947), the RLM cancelled its development in May 1943. And, along with the DB 609 cancellation, so went the Daimler Benz Jäger project.

View attachment 799903 Pic by Marek Rys

In a timeline where Daimler Benz joined with Messerschmitt to develop their DB Jäger design (The RLM cancelled all work on the Me-262 believing the plane wouldn't be ready till after the war was won) while Daimler Benz focused on developing the DB609 engine in 1942.
View attachment 799908.
The Me/DB Jäger-609 entered service in the spring of 1945 after a long and troublesome development program.

Als technischer Laie Frage ich mich, wie bei dieser "Konstruktion" das Heck mit dem Rest des Flugzeuges verbunden sein soll, reines Wunschdenken hält es wohl kaum an seinem Platz.

 

[oldironside]

Als technischer Laie Frage ich mich, wie bei dieser "Konstruktion" das Heck mit dem Rest des Flugzeuges verbunden sein soll, reines Wunschdenken hält es wohl kaum an seinem Platz.

Können wir das auf Englisch diskutieren?

 

[Katzman]

Sorry I am German. In english I could'nt write exactly what I want top say.

 

[oldironside]

Sorry I am German. In english I could'nt write exactly what I want top say.

Personally I don't have a problem with that but the mods might. If you want to PM me auf Deutsch I can maybe help you out.

 

[Caledon]

Sorry I am German. In english I could'nt write exactly what I want top say.

fwiw, Google translates your post to this:

As a technical layman I'm wondering how the tail is supposed to be connected to the rest of the plane with this "construction", wishful thinking is unlikely to keep it in place.

Which I have to say, I agree with. I didn't see the problem at first, but once I started thinking about how the power would get to those propellers, I cannot figure out how they could connect everything.

A big hollow driveshaft with a really strong iron bar down the middle to bolt the tail onto?

 

[cortz#9]

Sorry I am German. In english I could'nt write exactly what I want top say.

fwiw, Google translates your post to this:

Which I have to say, I agree with. I didn't see the problem at first, but once I started thinking about how the power would get to those propellers, I cannot figure out how they could connect everything.

A big hollow driveshaft with a really strong iron bar down the middle to bolt the tail onto?

Perhaps a twin tail would've been a better design?