Why no Fw 190H but the Ta 152H? (1 Viewer)

[tomo pauk]

To further this, there were 3 companies, not 3 factories.

Jumo was probably the 1st among the 'mainstream' German aero engines' companies to introduce a 'proper', pressure oil feed via the crankshaft, with DB following suit years later. BMW was tackling that issue by some time 1940-41.
BMW was the 1st to chrome-plate the valves, again DB following suit about a full year later.

Wholesale cancellation (that 'deleting' the development in company actually is) might mean the other companies don't get the benefits of cross-pollination, as imperfect it already was in Germany. Having company A just as another source, without a competing engine, means that company B grows complacent, too, even during the war.

tl;dr - making the things simple is okay, but making them too simple can make the things even worse

 

[z42]

To expand on that.
time to "take out" a manufacturer is before the shooting starts.
Once the shooting starts (or at least by 1941) it is too late for the Germans. Trying to retool either V-12 company to make radials or retool BMW to make V-12s is going to mean months of lost production. How long before the 'increased efficiency" of higher mass production catches up to the lost production from the change over?

Oh, absolutely. Perhaps I wasn't clear about that. If you want to get rid of BMW, say, the RLM probably have to tell them in 1935 instead of funding development of what eventually became the 801 that they should concentrate on building the 132 as a second-tier engine, and then focus R&D on jets.

Big changes in the middle of the war is a recipe for disaster.

To further this, there were 3 companies, not 3 factories. BMWs and Jumos were built in France and Jumos were built in Czechoslovakia.

Of course. But setting up a new factory is less effort than developing a new engine, and then building a factory to produce said engine.

In 1941-42 the BMW can do things the DB 601-605 and Jumo 211s cannot do, means you need to get the DB 603/Jumo 213 into production sooner.

If we take Tomo's suggestion of a slightly lighter-weight FW190 with a DB 601 (and slightly later a 605, presumably) instead of the historical FW 190A, then we don't need the 801.

And the best is the enemy of good. With limited high octane fuel perhaps more attention should have been paid to inter-cooling/after cooling on existing engines for a modest improvement in performance instead of the using tricks like nitrous oxide, which did give great performance but at the cost of weight/volume and logistics/servicing.

Jumo was probably the 1st among the 'mainstream' German aero engines' companies to introduce a 'proper', pressure oil feed via the crankshaft, with DB following suit years later. BMW was tackling that issue by some time 1940-41.

IIRC from Calum Douglas book, the 213 (forget if it was only the J or all models) had very efficient cooling channels for the head and valve guides, which probably were helpful for avoiding detonation.

BMW was the 1st to chrome-plate the valves, again DB following suit about a full year later.

Probably because the 801, being air-cooled, ran hotter and thus ran into the valve material issues more severely than the liquid cooled ones?

Wholesale cancellation (that 'deleting' the development in company actually is) might mean the other companies don't get the benefits of cross-pollination, as imperfect it already was in Germany. Having company A just as another source, without a competing engine, means that company B grows complacent, too, even during the war.

tl;dr - making the things simple is okay, but making them too simple can make the things even worse

Yes, you absolutely want to avoid a monopoly. But in an industry with high R&D costs and economies of scale, a duopoly is a sort-of stable equilibrium. The UK had RR and Bristol (with Napier tagging along as a sort of third wheel), the US had Wright and P&W in radials, and Allison vs. RR/Packard in inlines (Though the US had the scale that they could afford lots of efforts going in almost every direction).

 

[tomo pauk]

IIRC from Calum Douglas book, the 213 (forget if it was only the J or all models) had very efficient cooling channels for the head and valve guides, which probably were helpful for avoiding detonation.

IIRC already the 211 have had the cooling channels for the exhaust valves.

 

[Just Schmidt]

IIRC already the 211 have had the cooling channels for the exhaust valves.

I sometimes wonder, was the jumo 211 really that much worse an engine than the DB 601? And if so, in what way?

 

[tomo pauk]

I sometimes wonder, was the jumo 211 really that much worse an engine than the DB 601? And if so, in what way?

Difference was not that huge, but was noticeable. Eg. the Jumo 211A was much later than the DB 600s that powered a lot of He 111s, and was even a few months later than the DB 601A. The 601 strikes me as being with the slight (talk ~10%) better power at altitude when we compare the versions available in a month of the war we choose to take a look. 211 was a bit better wrt. the take-off power as the war progressed, while the 601 morphed into the 605.
The ultimate 211s, like the R (roughly equivalent of the de-rated 605A wrt. the altitude power, but way too late) and Q (turbocharged version) seems like that never flew operationally.
Jumo (company) was many times reluctant to rate the 211s for the 'Notleistung' power setting - that is understandable if the engine is on the bomber, but that is major point on a fighter, like the night-fighter Ju 88s. Seesm like that it was Fw - that was mostly basing their performance calculations (and tests, as one might expect) of the Ta 154 - was the true believer in the higher power settings of the 211s, but, since the Ta 154 ended us as a footnote in the ww2, I'm not sure how well the 211s were suited for that.

 

[Denniss]

The 211 had a classic two-speed supercharger. It probably lacked some power with its 3-valve design instead of 4-valve on DB engines.
It was never really intended for fighter use so they likely opted for a longer service life instead of maximum power.

 

[spicmart]

From the vast spaces of the web a Dora with 14% longer fictitious wing span of 12 m (same as the Ki-61/100), growing from out of the wing roots, aspect ratio ~7.2.
A bit less than the historical 12.3 m wing of the Fw 190H where the tips were lengthened. Wing area should be about the same, 20 to 21 sqm (or m^2?).

Looks pretty good imho.

 

[spicmart]

About the Luftwaffe going with the kinda overweight Ta 152 sacrificing one-on-one ability I can only come to the explanation that they would attack bombers from a superelevation (now that they have competitive or better superchargers) and evade the escort fighters via faster dive. Their exceptionally heavy weaponry should give them a one strafe-one kill ability.
At least the short-wing variants were not to/could not tangle with the escort fighters imo.

 

[Holtzauge]

I see that the question of the weight of the steel winged version of the Ta-152C came up earlier in this thread and that there was an unsourced weight of an additional 250 kg mentioned in comparison to the Dural aluminium wing.

I found a more precise number in Wolfgang Werner's book about Kurt Tank (Bernand & Graefe Verlag): This states that the steel wing version weighed 224 kg more.

I'm assuming here that the Ta-152C had the same wing area (19.5 sqrm) as the Ta-152H-0 has, as opposed to the 23.5 sqrm on the long winged Ta-152H-1.

If so, then the "Baubeschribung Nr. 292" for the Ta-152H gives the wings weights as 629 kg for the H-0 and 654 kg for the H-1 with Dural wings.

So if no redesign of the Ta-152C wing was done, and it instead was done in steel with the same dimensions it would weigh 629*7.8/2.7=1817 kg. So this means all of 1188 kg more.

But if it "only" weighed 224 kg more, i.e. 853 kg, this means that the designers really made an effort to lower the weight by re-dimensioning it, given that they managed to cut almost a ton off the weight.

 

[spicmart]

I see that the question of the weight of the steel winged version of the Ta-152C came up earlier in this thread and that there was an unsourced weight of an additional 250 kg mentioned in comparison to the Dural aluminium wing.

I found a more precise number in Wolfgang Werner's book about Kurt Tank (Bernand & Graefe Verlag): This states that the steel wing version weighed 224 kg more.

I'm assuming here that the Ta-152C had the same wing area (19.5 sqrm) as the Ta-152H-0 has, as opposed to the 23.5 sqrm on the long winged Ta-152H-1.

If so, then the "Baubeschribung Nr. 292" for the Ta-152H gives the wings weights as 629 kg for the H-0 and 654 kg for the H-1 with Dural wings.

So if no redesign of the Ta-152C wing was done, and it instead was done in steel with the same dimensions it would weigh 629*7.8/2.7=1817 kg. So this means all of 1188 kg more.

But if it "only" weighed 224 kg more, i.e. 853 kg, this means that the designers really made an effort to lower the weight by re-dimensioning it, given that they managed to cut almost a ton off the weight.

Not sure if I understand what you mean. Are you taking the difference in mass of steel and dural?

Do you mistake the H-0 = C wing? As far as I know ALL Ta 152H-wings were of the long version with 23.5 sqm.

Cutting one ton off the wing structure is quite something.

There might be another explanation for the difference in weight of the H-0 and H-1 wings.
The H-0 wing had a standard main forward spar which went all the way to the wing tip.
The new H-1 wing had a shortened spar which only went as far as to the main under carriage attachment, * Nr. 143 "Abbreviated steel front spar"
After that the wing structure consisted of * Nr. 153 "lateral stringers".
I don't know how much the weight difference is between those two construction methods.
The H-1 wing had internal tanks for fuel and MW50 installed. This was probably not possible with the standard wing (or at least not to such extent).
That's why the H-0 had considerably less range.

* See here:

TA152H-1 Cutaway

ww2aircraft.net

 

[spicmart]

Torsional stiffness of the H-1 wing with its lateral stringers in comparison to a "normal" wing structure would be interesting as well.

 

[Holtzauge]

Not sure if I understand what you mean. Are you taking the difference in mass of steel and dural?

Do you mistake the H-0 = C wing? As far as I know ALL Ta 152H-wings were of the long version with 23.5 sqm.

Cutting one ton off the wing structure is quite something.

There might be another explanation for the difference in weight of the H-0 and H-1 wings.
The H-0 wing had a standard main forward spar which went all the way to the wing tip.
The new H-1 wing had a shortened spar which only went as far as to the main under carriage attachment, * Nr. 143 "Abbreviated steel front spar"
After that the wing structure consisted of * Nr. 153 "lateral stringers".
I don't know how much the weight difference is between those two construction methods.
The H-1 wing had internal tanks for fuel and MW50 installed. This was probably not possible with the standard wing (or at least not to such extent).
That's why the H-0 had considerably less range.

* See here:

TA152H-1 Cutaway

ww2aircraft.net

Yes, I'm talking about the difference in weight for the Ta 152 variant with the 19.5 sqrm shorter wing, not the 23.5 sqrm wing. Since there was a version of this shorter wing built in steel and there was some speculation about weights and how much more the steel wing weighed.

And yes, while no structural engineer would ever dream of using exactly the same dimensions in a steel wing as one made of aluminium, it's still impressive that they managed to make it only 224 kg heavier, since while you on the tension side can use the full strength of the steel, on the compression side buckling will set the limit. And then since you have a negative g-load to contend with as well, this means that buckling can occur on both the top and lower wing surface. In addition, shear loads can also buckle webs etc. so quite a lot of re-design work needed. In addition to proof testing etc.

But as far as I know the H-0 did have the same 19.5 sqrm wing as the C-1 and that the H-0 refers to the Jumo 213 engined variant and the C-1 to to the DB 603 engined variant.

The table below is from Wolfgang Werner's book about Kurt Tank I referenced earlier.

 

[dedalos]

According to Harmann both the H-0 and H-1 had the 14,4m wings

 

[spicmart]

Yes, I'm talking about the difference in weight for the Ta 152 variant with the 19.5 sqrm shorter wing, not the 23.5 sqrm wing. Since there was a version of this shorter wing built in steel and there was some speculation about weights and how much more the steel wing weighed.

And yes, while no structural engineer would ever dream of using exactly the same dimensions in a steel wing as one made of aluminium, it's still impressive that they managed to make it only 224 kg heavier, since while you on the tension side can use the full strength of the steel, on the compression side buckling will set the limit. And then since you have a negative g-load to contend with as well, this means that buckling can occur on both the top and lower wing surface. In addition, shear loads can also buckle webs etc. so quite a lot of re-design work needed. In addition to proof testing etc.

But as far as I know the H-0 did have the same 19.5 sqrm wing as the C-1 and that the H-0 refers to the Jumo 213 engined variant and the C-1 to to the DB 603 engined variant.

The table below is from Wolfgang Werner's book about Kurt Tank I referenced earlier.

View attachment 781003

Interesting. Haven't seen the H-0/19.5 sqm combo anywhere else before. Does that mean all the model kit manufacturers like Zoukei-Mura which make
Ta 152H-0 models with long wings succumbed to false research?

 

[Holtzauge]

Interesting. Haven't seen the H-0/19.5 sqm combo anywhere else before. Does that mean all the model kit manufacturers like Zoukei-Mura which make
Ta 152H-0 models with long wings succumbed to false research?

According to Harmann both the H-0 and H-1 had the 14,4m wings

On second thoughts I'm beginning to think you are right about the H-0 having the same wing size as the H-1 and that the table in Werner's book is wrong:

If we assume 654 kg for the 23.5 sqrm wing (this is what the Ta 152 H Baubeschribung Nr. 292 states for the H-1), then a first order approximation of the weight for the 19.5 sqrm wing would be 19.5/23.5*654=543 kg. So that's a 111 kg in weight difference. But since the number for the H-0 wing in the Baubeschribung is 629 kg, this gives a weight difference of only 25 kg. And that difference seems more consistent with the weight of the extra wing tank, not an additional 4 sqrm wing area.

But it's intriguing that Werner's table is so specific: It's not just a statement out of the blue because he actually lists the W. Nr. 150001 to 150018 as having 19.5 sqrm in the table, and then even has a note specifically saying these first "Werknummern" had the 19.3 sqrm wing.

 

[spicmart]

I asked about this issue on this German forum here:

Ta 152H-0 Flügel?

Ein Mitglied eines anderen englischsprachigen Forums hat folgendes gepostet, siehe unten. Es ist ein Auszug aus Wolfgang Werners "Kurt Tank: Konstrukteur und Chefpilot bei Focke Wulf". Daraus geht hervor, dass der Flügel der Ta 152H-0 der normale kurze Flügel mit 19,5 m^2 gewesen sein soll...

www.flugzeugforum.de

I took the liberty to use your picture. I hope you don't mind.

 

[Holtzauge]

I asked about this issue on this German forum here:

Ta 152H-0 Flügel?

Ein Mitglied eines anderen englischsprachigen Forums hat folgendes gepostet, siehe unten. Es ist ein Auszug aus Wolfgang Werners "Kurt Tank: Konstrukteur und Chefpilot bei Focke Wulf". Daraus geht hervor, dass der Flügel der Ta 152H-0 der normale kurze Flügel mit 19,5 m^2 gewesen sein soll...

www.flugzeugforum.de

I took the liberty to use your picture. I hope you don't mind.

That seems to have been a good idea!

I see one user there posted a nice figure with a weight estimate for the Ta 152 C steel wing which seems to be the sum of 424 kg steel and 200 kg aluminium for a total of 624 kg. This seems logical, given that the first order approximation for a "pure" Dural 19.5 sqrm wing based on the weight of the 23.5 sqrm wing was 543 kg.

If so then there is another error in Werner's book since there the weight is stated to be 224 kg heavier, i.e. assuming that the total weight of the Dural wing was 200 kg and that the steel wing weighed 224 kg more, i.e. 424 kg in total.

 

[spicmart]

Wrong post.

 

[Holtzauge]

Spicmart: The discussion in the German forum you linked above seems to have converged now as well: And it would seem that Werner's book could do with an update!

 

[spicmart]

Spicmart: The discussion in the German forum you linked above seems to have converged now as well: And it would seem that Werner's book could do with an update!

Yes, I've read. The author's name is actually Wolfgang Wagner and his reputation is quite dubious to say the least.