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zxwings
09-11-2009, 10:37 PM
In WWII, at what speed did the the B-17 usually fly over German territory? And is that the speed at which these bombers approached the target and dropped bombs?

It is said that its cruise speed is 182 mph (293 km/h), but I'm not sure whether they were flown at this speed over Germany.

zxwings
09-11-2009, 10:37 PM
In WWII, at what speed did the the B-17 usually fly over German territory? And is that the speed at which these bombers approached the target and dropped bombs?

It is said that its cruise speed is 182 mph (293 km/h), but I'm not sure whether they were flown at this speed over Germany.

Waldo.Pepper
09-11-2009, 10:41 PM
What is the bomb load, weather, wind speed and direction?

zxwings
09-11-2009, 10:44 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Waldo.Pepper:
What is the bomb load, weather, wind speed and direction? </div></BLOCKQUOTE> No wind; loaded in the way that they were most often loaded. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif

M_Gunz
09-11-2009, 11:24 PM
You mean on the way in, right? Even then as time went by and fuel was burned those bombers could run faster for
the same effort. I'm sure that the crews did not want to spend seconds longer than necessary getting to target
and back out of extreme danger.

Tully__
09-11-2009, 11:25 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by zxwings:
...loaded in the way that they were most often loaded. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>
Which varied dramatically depending on distance to target. The total weight of the aircraft load was a combination of fuel and bomb load. If the target was in south east Germany and the aircraft were attacking from England the bomb load would be considerably reduced to carry extra fuel. For trips to north west Germany the bomb load could be quite a bit heavier as much less fuel was required.

Waldo.Pepper
09-11-2009, 11:56 PM
There is no such thing as average, or typical in the real world. But in case you choose to live in a simpler less complex more Unicorn filled world with no wind. Here you go. --

http://www.taphilo.com/Photo/Pictures/b17/index.shtml

P51er
09-12-2009, 12:35 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Waldo.Pepper:
There is no such thing as average, or typical in the real world. But in case you choose to live in a simpler less complex more Unicorn filled world with no wind. Here you go. --

http://www.taphilo.com/Photo/Pictures/b17/index.shtml </div></BLOCKQUOTE>

Wrong. You can take an average of most any measurable natural phenomena over a given time. Wind speed certainly qualifies.

Maybe you should ride that unicorn to a stats class.

zxwings
09-12-2009, 12:42 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by M_Gunz:
I'm sure that the crews did not want to spend seconds longer than necessary getting to target
and back out of extreme danger. </div></BLOCKQUOTE>
I thought the same; I was wondering whether they would try to fly at max speed when above enemy terroritry (especially when German fighters came to attack them).

zxwings
09-12-2009, 01:00 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Tully__:
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by zxwings:
...loaded in the way that they were most often loaded. http://forums.ubi.com/groupee_common/emoticons/icon_smile.gif </div></BLOCKQUOTE>
Which varied dramatically depending on distance to target. The total weight of the aircraft load was a combination of fuel and bomb load. If the target was in south east Germany and the aircraft were attacking from England the bomb load would be considerably reduced to carry extra fuel. For trips to north west Germany the bomb load could be quite a bit heavier as much less fuel was required. </div></BLOCKQUOTE>
I did underestimate such difference, haha http://forums.ubi.com/groupee_common/emoticons/icon_razz.gif.

But the speeds of the B17 formations would not vary as dramatically as the load did, I suppose. The bomb load only influences the top speed of the aircraft, but whether to always run as fast as ever possible is decided by the pilot, there being a huge difference of more than 150km/h between max speed and cruise speed of the B17.

Waldo.Pepper
09-12-2009, 01:00 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">I was wondering whether they would try to fly at max speed when above enemy territory (especially when German fighters came to attack them). </div></BLOCKQUOTE>

If they did that then their formation would spread out, and consequently their defencive firepower would suffer. Another trade off to consider. It may all come down the the values of the the person in command.


EDIT: typo again!

Sillius_Sodus
09-12-2009, 01:01 AM
According to this site, B-17's flew at 155mph indicated (IAS) while in formation. At 25000 feet this would give yo a true airspeed (TAS) of around 232mph


http://www.taphilo.com/Photo/P...B24-comparison.shtml (http://www.taphilo.com/Photo/Pictures/b17/B17-B24-comparison.shtml)

IAS to TAS converter:

http://www.csgnetwork.com/tasinfocalc.html

jarink
09-12-2009, 04:31 PM
From everything I've read (which is more than a little bit), speed was normally in the region of 150-160 mph IAS when flying to the target. Coming home, the speed would step up to 170-180 mph. The main reason for the increased speed was that the planes would be a few tons lighter (no more bombs and less fuel).

Zeus-cat
09-12-2009, 05:28 PM
The B-17 was designed to be a self-defending aircraft that did not need fighter support. Of course, it didn't work out that way. Speed would not have been a big concern for an aircraft that could defend itself agianst enemy fighters.

Bomber formations would have to fly at a speed that was sustainable for all undamaged aircraft in the group, and also allowed all planes to keep their station in that formation, and fuel efficient. Planes had to keep their station to provide maximum defensive fire as well as to know when to drop their bombs. Typically, only the lead aircraft and a few backups had a bombardier. The vast majority of planes carried a toggileer who released the bombs based on orders from the lead aircraft.

Lt_Letum
09-12-2009, 06:13 PM
150-160mph IAS was typical, as others have pointed out.

The B17 was capable of gong much faster, even in
formation, but a slow speed allowed stragglers to
catch up and damaged aircraft to stay with the
formation longer.

Formation integraty is much more important for
the B17 than speed.

zxwings
09-13-2009, 01:28 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by jarink:
From everything I've read (which is more than a little bit), speed was normally in the region of 150-160 mph IAS when flying to the target. Coming home, the speed would step up to 170-180 mph. The main reason for the increased speed was that the planes would be a few tons lighter (no more bombs and less fuel). </div></BLOCKQUOTE>
Thank you jarink! That's just what I want to know http://forums.ubi.com/groupee_common/emoticons/icon_wink.gif.

zxwings
09-13-2009, 01:32 AM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Zeus-cat:
The B-17 was designed to be a self-defending aircraft that did not need fighter support. Of course, it didn't work out that way. Speed would not have been a big concern for an aircraft that could defend itself agianst enemy fighters.

Bomber formations would have to fly at a speed that was sustainable for all undamaged aircraft in the group, and also allowed all planes to keep their station in that formation, and fuel efficient. Planes had to keep their station to provide maximum defensive fire as well as to know when to drop their bombs... </div></BLOCKQUOTE>

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Lt_Letum:
150-160mph IAS was typical, as others have pointed out.

The B17 was capable of gong much faster, even in
formation, but a slow speed allowed stragglers to
catch up and damaged aircraft to stay with the
formation longer.

Formation integraty is much more important for
the B17 than speed. </div></BLOCKQUOTE>
:nod:

stiboo2
09-13-2009, 04:46 AM
Yes always listen to JaRink - the B17 expert, and B17 skinning God!

If anyone is intersted - I've just started building the final mission of my B17 campaign -

"HELLS ANGELS" the 303rd BG, Tour Of Duty 1

in which you fly the B17 'Hell's Angels' between Nov42 - Aug43 , the Hell's Angels was the first B17 to complete 25 missions in Europe, and the 303rd became an elite unit in the 8th Airforce.

Just got to finish this last mission, play-test, make some videos, and complete skins and should be reasy for release by end Sept, oohh thats about 'two weeks'....

Simon

zxwings
09-13-2009, 07:57 PM
<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by jarink:
From everything I've read (which is more than a little bit), speed was normally in the region of 150-160 mph IAS when flying to the target. Coming home, the speed would step up to 170-180 mph. The main reason for the increased speed was that the planes would be a few tons lighter (no more bombs and less fuel). </div></BLOCKQUOTE>
http://forums.ubi.com/groupee_common/emoticons/icon_smile.gifOh, I have to ask more questions. At what altitude were they flying? Did they keep the same altitude after bombing the target? I need to convert IAS to TAS.

jarink
09-13-2009, 09:01 PM
Altitude varied greatly depending on the target (the larger the target, the higher they could fly while still being able to hit it) and weather conditions. Generally speaking, formations would not keep the same altitude right after bombs away to throw off Flak.

Waldo.Pepper
09-13-2009, 10:12 PM
http://img.photobucket.com/albums/v516/WaldoPepper/Bombing%20Altitude/bombingaltitude.jpg

zxwings
09-14-2009, 01:08 AM
Waldo.Pepper, that table is very informative indeed! Thank you for posting it!

And thanks again jarink!

Trinity_Jay
09-16-2009, 05:01 AM
Howdy all,

This is from a book that I am currently evaluating for a possible commission on a B-17 bombadier.

S!

Jay
CPS_Bulldog

In 1944, the price tag for a B-17 was a little more than $204,000. It carried a crew of 10, had a wingspan of nearly 104 feet, and was armed with thirteen 50-calibre machine guns, including the two located in the new chin turret of the B-17G model. Its four 1,200 hp Wright cyclone engines could power it to fly at a cruising speed of 160 mph with a 35,000 foot ceiling.

ďIn the air or on the ground with its 1,200 h.p. engines in sync, there was a certain thundering rendition of sound pleasant to the ear and unique to the aircraft. Even at 160 mph cruising speed, there was nothing serene about the cry of the engines. They labored in concert with each other and when they didnít it didnít take a pilot or flight engineer to know trouble loomed. Every man on the crew got to know the comforting, pulsating rhythm of those power plants.Ē

William Somers

taphilo
09-30-2009, 03:51 PM
The NORMAL speed that B-17s flew in formation was at 155 MPH INDICATED airspeed. From combat reports that I have read it was reported that a low of 135 to a high of 170 were reported while in formation (and HIGHLY complained about when low or high) in combat operations.

B-24s flew at 165 MPH indicated due to the Davis wing - and thus after a few tries of mixed formations 17s and 24s never flew in the same combat formation but often flew to the same targets - just getting there at different times and as their own separate bomb groups.

I have no hard data on B-26s, B-25s - don't know any WWII pilots who flew them locally, just lots of 17 and 24 pilots, as to their normal operating formation speed. From reading they are around 170 for B-26s and 25s.

erco415
09-30-2009, 07:11 PM
The 'Galloping Goose', an open cockpit B-17 (not to be confused with the Aphrodite B-17s) was faster than the B-24. As they sailed by and through the 24 formations, the AC would often stand up and salute!