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He-177 and derivatives

Started by GTX, March 12, 2011, 02:37:47 PM

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KJ_Lesnick

wuzak

QuoteMakes you wonder why the DB606/610 wasn't selected for the Me 264.
You mean 4 x DB606/DB610?

QuoteThe DB606 was rated at ~2,700hp, so would have been a useful increase in power.
I made some estimates for power-loading for the Me-264 (at least the Amerika Bomber versions), and I get around 0.066 hp/lbs in a loaded configuration (105380 lbs based on the listed OEW, fuel, oil, and stuff, I'm probably off by 2000 pounds armament and all), and full weight (123459 lbs) power-loading of a little under 0.0567 lbs/hp

That's actually worse than the B-29, who's power-loadings were as follows

  • 0.0733 lbs/hp @ 120,000 lbs
  • 0.0652 lbs/hp @ 135,000 lbs
And it was considered underpowered...

The DB606 would yield, for the Me-264 the following weights

  • 105380 lbs: 0.0973-0.1025 lbs/hp
  • 123459 lbs: 0.0831-0.0874 lbs/hp
The DB610 would yield at the following weights

  • 105380 lbs: 0.1085 lbs/hp
  • 123459 lbs: 0.0925 lbs/hp
QuoteThe interesting thing about the DB606 and 610 was that it was literally two separate engines which, unlike the Allison V-3420, could be perated independently, each half having its own supercharge and accessories.
This honestly makes it seem more practical to have just used 4-engines...
That being said, I'd like to remind everybody in a manner reminiscent of the SNL bit on Julian Assange, that no matter how I die: It was murder (even if there was a suicide note or a video of me peacefully dying in my sleep); should I be framed for a criminal offense or disappear, you know to blame.

wuzak

Quote from: KJ_Lesnick on November 13, 2015, 06:51:31 PM
QuoteThe interesting thing about the DB606 and 610 was that it was literally two separate engines which, unlike the Allison V-3420, could be perated independently, each half having its own supercharge and accessories.
This honestly makes it seem more practical to have just used 4-engines...

Yes and no.

The twin engine installation offered a drag advantage, while still having 4 engines. Having 4 engines in separate nacelles would have offered a simpler solution, each engine requiring a smaller prop than the DB606 did.




KJ_Lesnick

wuzak

QuoteYes and no.

The twin engine installation offered a drag advantage, while still having 4 engines.
Correct, and as I said: Had they designed the nacelle and cowling right, they would not have had problems (though it might have been slower).

QuoteHaving 4 engines in separate nacelles would have offered a simpler solution, each engine requiring a smaller prop than the DB606 did.
Generally, I prefer a simpler solution over a complicated one.  Especially when one considers the dive-bombing capability was largely unnecessary.


BTW: I'm curious as to whether the B-29's could have done descending bombing approach similar to the He-177's in Steinbock (except starting out at 31,500): The plane could go at least 405 mph (XB-39), not sure how much faster.
That being said, I'd like to remind everybody in a manner reminiscent of the SNL bit on Julian Assange, that no matter how I die: It was murder (even if there was a suicide note or a video of me peacefully dying in my sleep); should I be framed for a criminal offense or disappear, you know to blame.

ysi_maniac

Airliner derivative of He-177along with her ancestor.

Will die without understanding this world.

KJ_Lesnick

#49
The nacelles were mounted fairly far back inside the wing and this caused problems with the DB606 because of the fact that this meant that fuel-lines, electrical harnesses, were basically all positioned around the engine: Why were they mounted as far back as they were?

Instinctively, I assume this was for drag-reduction: I'm curious if it was actually necessary to meet the requirements dictated by the RLM?
That being said, I'd like to remind everybody in a manner reminiscent of the SNL bit on Julian Assange, that no matter how I die: It was murder (even if there was a suicide note or a video of me peacefully dying in my sleep); should I be framed for a criminal offense or disappear, you know to blame.

wuzak

Quote from: KJ_Lesnick on July 16, 2016, 06:14:39 PM
The nacelles were mounted fairly far back inside the wing and this caused problems with the DB606 because of the fact that this meant that fuel-lines, electrical harnesses, were basically all positioned around the engine: Why were they mounted as far back as they were?

Instinctively, I assume this was for drag-reduction: I'm curious if it was actually necessary to meet the requirements dictated by the RLM?

It was just as likely structural considerations. The DB 606 was a rather heavy beast.

ysi_maniac

Will die without understanding this world.

ysi_maniac

Will die without understanding this world.

wuzak

Quote from: KJ_Lesnick on July 18, 2016, 07:54:47 PM
ysi_maniac

I'm looking at the drawings shown of the He-277 and He-274 and both of them seem to have their engines recessed close to the wing.  For the most part, I'm largely curious why the plane would need to have the engines recessed so back.

Is it strengthening, streamlining, or both?

Is this keeping you awake at night?

This may help you:
https://s-media-cache-ak0.pinimg.com/736x/2f/ae/8d/2fae8d59778eae741842b13628f8b4ec.jpg

ysi_maniac

Schnelltransport, staff or cargo, extra tankage under cabin, based on He-177

Will die without understanding this world.

NARSES2

Do not condemn the judgement of another because it differs from your own. You may both be wrong.

ysi_maniac

#56
Variations on He-177 theme (first one is RW)

Will die without understanding this world.

NARSES2

I like those Carlos  :thumbsup: , but then I've always liked the 177 and its derivatives.
Do not condemn the judgement of another because it differs from your own. You may both be wrong.