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-   -   B17 v Lanc bomb load (https://www.pprune.org/aviation-history-nostalgia/273874-b17-v-lanc-bomb-load.html)

45-Shooter 17th Apr 2012 05:56

Just could not resist?
 
Quote "For higher altitudes we can bring in the B17 replacement - the B29; an altogether more worthy contestant against the Lancaster.
Regards,
Rich
(self confessed Avro fanatic)"

I found this link to compare Lancaster and B-29 bomb loads. See if you do not find it interesting. By the way. I had visited the foundry in question when I was a kid!

The Extra-Super Blockbuster

Weheka 17th Apr 2012 08:46

"You missed the schwinfurt raid with ~660 bombers, IIRC."

Absolute rubbish, by "raid" I would assume you mean one of the Schweinfurt raids, there were two main ones, and probably others I am not aware of.
The first on August 17th 1943 saw 230 B17s sent to that city, plus 146 to Regensburg, result 60 aircraft lost. The second raid on Oct 14th of the same year saw 291 B17s go to Schweinfurt, and just to prove the first raid was not a fluke, the Germans again dispatched 60 of the raiders.

Noyade 17th Apr 2012 09:26


The B-17 could haul the maximum load of 17,600 pounds to 1,100 miles! Page 206 of Janes
If it's the 45-46' Jane's, then I think not mate. There is no mention of 17,600 lbs.

It states the "normal range (maximum bomb load and normal fuel) 1,100 miles @ 220mph at 25,000 ft".
In the armament section it makes it clear - "External racks no longer fitted".

I believe "maximum" is referring to 12,800 lbs, based on other sources.

Here's the Range/Bomb load figures according to the Australian War Memorial...

http://img819.imageshack.us/img819/6608/img581t.jpg

(Does anyone have photos of B-17s on their way to Hun-land with bombs attached to the under-wing racks?)

Lightning Mate 17th Apr 2012 09:47

Here's one:

http://i636.photobucket.com/albums/u...ng_29/B-17.jpg

Noyade 17th Apr 2012 10:17

Thanks mate. But when carrying the BG series of gliders I doubt the internal bay was carrying anything. I could be wrong though.

http://img15.imageshack.us/img15/3362/img583j.jpg

No, I'm looking for a 17,600 lb jobber with traditional bombs on the wing racks.

Lightning Mate 17th Apr 2012 10:19

Whilst you are doing that then, get back over to SC.

Agaricus bisporus 17th Apr 2012 10:27

Anyone able to provide the equivalent figires for a Lanc?
I expect the bottom line will read max load 22,000lb external racks not required. And that's nearly double the B17s normal max. Its also 2 tons more than the B17s max max...Can't imagine what the drag of external racks and stores would have done to the range.And while we're at it , how far could a Mosquito haul 4000lb?

Noyade 17th Apr 2012 10:41

No Racks Required
 
http://img404.imageshack.us/img404/8964/img584.jpg

Noyade 17th Apr 2012 10:49


how far could a Mosquito haul 4000lb
:ok:

http://img404.imageshack.us/img404/1314/img585.jpg

Noyade 17th Apr 2012 11:23


I'm looking for a 17,600 lb jobber with traditional bombs on the wing racks.
Found some...

351st BS - Page 28

http://img841.imageshack.us/img841/824/48785951.jpg

So, what is the range, carrying 17,600 lb?

Agaricus bisporus 17th Apr 2012 17:11

Thanks Noyade. Interesting comparison.

Here's a link that includes more detail about external B17 ordnance inc a pic.

Disney bomb - Wikipedia, the free encyclopedia

45-Shooter 22nd Apr 2012 23:09

What is your honest opinion of the two planes if they had been required to swap missions? Lancs restricted to day light bombing for the entire war and B-17s allowed to bomb at night. Using the Grand Slam argument is silly because the B-17 could conceivably be modified to carry the Short, but Fat Man; 22 Kilo tonnes to 22,000 pounds. The lancaster's bomb bay was not nearly tall enough to carry that bomb load. So lets get off of the idea of the 33 or so Lancs that were specially modified to carry GS. It is the mission that dictates how many bombs you carry.

The first ~3,800 or so Lancasters could haul 14,000 pounds. Certainly more than the first ~1000 or so B-17s. The last ~4000 or so Lancs could carry 18,000 pounds, more than any of the last 8000+ B-17s. But none of that is applicable because it was Mission Planning that made both planes carry much less, so that the average for all missions was ~4,500 pounds for the B-17s and ~7,800 pounds for the Lancaster. If their rolls would have been reversed, the AVERAGE bomb loads would have also been reversed! Because load and Range are fungible, you can trade one for the other at will, over any but the shortest ranges. Because the B-17 was/is/and always will be more efficient aerodynamically, it will always win that trade off at any but the shortest ranges. Always! Because of that aerodynamic advantage it will always fly higher at any given weight. These two facts are not in dispute. You keep going back to the various placard numbers, but you have never explained why the Lancaster could carry 18,000 pounds but could only AVERAGE less than 8000 pounds per mission?

Richard Woods 23rd Apr 2012 09:46

What is your honest opinion of the two planes if they had been required to swap missions?

No opinion needed. The B17 was used at night by the RAF, and the Lancaster did bomb by day.

Lancs restricted to day light bombing for the entire war and B-17s allowed to bomb at night. Using the Grand Slam argument is silly because the B-17 could conceivably be modified to carry the Short, but Fat Man; 22 Kilo tonnes to 22,000 pounds.

Conceivably, the Lancaster could carry several "Little Boy" weapons. Given the size of 120" x 28" and a weight of 9,000lbs you could get a couple in a standard BIII with the doors closed, and be at a comfortable 18,000lbs. What's your point?

In reality the B17 was never considered for atomic bombs, where the Lancaster was. It was the logistics that prevented it.

The lancaster's bomb bay was not nearly tall enough to carry that bomb load.

Whoops. Wrong again. What carriers did the atomic bombs use? "Grand Slam" ones. Guess what aircraft they fit, and what aircraft they don't.

So lets get off of the idea of the 33 or so Lancs that were specially modified to carry GS. It is the mission that dictates how many bombs you carry.

Mission may dictate how much you are required to carry - not how much you can. This is why your argument is pointless. A B17 or a Lancaster may have been ordered to carry a kettle, a cuddly toy and a fondue set, but it doesn't mean its all its capable of.

The first ~3,800 or so Lancasters could haul 14,000 pounds. Certainly more than the first ~1000 or so B-17s. The last ~4000 or so Lancs could carry 18,000 pounds, more than any of the last 8000+ B-17s. But none of that is applicable because it was Mission Planning that made both planes carry much less,

Mission planning has nothing to do with the physical capability of an aircraft.

so that the average for all missions was ~4,500 pounds for the B-17s and ~7,800 pounds for the Lancaster. If their rolls would have been reversed, the AVERAGE bomb loads would have also been reversed!

No it wouldn't, and they weren't. Lancasters bombed in daylight to Augsburg, and then several other daylight missions later in the war. The loads stay the same, becuase the targets are still as distant, and the aircraft still flies the same regardless of if daylight or not.

Because load and Range are fungible, you can trade one for the other at will, over any but the shortest ranges. Because the B-17 was/is/and always will be more efficient aerodynamically, it will always win that trade off at any but the shortest ranges. Always!

So you keep saying. But I've shown you - the B17 only wins at higher altitudes. If we use the Lancaster at altitudes its happy with (16,000ft) rather than try and force it up higher, its happy to carry 22,000lbs up there for 1600 miles.

The USAF manuals give figures for the B17 consistently less than that... 17,600lbs for 1000miles or so at 16,000ft. If we look at longer ranges, the B17 was down to 4,000lbs at its most stretched. By comparison the longest Lancaster missions were still carrying 9,000lbs at 2,000 miles. (East Kirkby - Munich, 630 Sqn, 1944)

Why you're ignoring this I don't know. I'm beginning to think you have a learning disability.

Because of that aerodynamic advantage it will always fly higher at any given weight.

Read above. It doesn't. At comparative loads to the Lancaster, its inferior at the same altitudes. Its only superior at high altitude; and only then because the Lancaster can't get to them. Up to its ceiling the Lanc outperforms the B17 in payload and range.

These two facts are not in dispute.

They are not facts. They're your opinion. The facts are what you find in manuals, books, and real life, not in your posts - and you've been proved wrong repeatedly.

You keep going back to the various placard numbers, but you have never explained why the Lancaster could carry 18,000 pounds but could only AVERAGE less than 8000 pounds per mission?

Maybe the multitude of other operations it did such as minelaying, leafleting, supply dropping to starving civilians, repatriating POW's, a little bit of work for Coastal Command, and specialist operations that required special payloads... stuff the B17 never got called upon to do in USAF service. Or maybe the fact that the loads were mixed depending on the job required.

The explanation is simple. The aircraft's capability is what it can truly carry, not what it is ordered to carry!

Rich

Agaricus bisporus 23rd Apr 2012 09:53

Richard, have you ever heard the quote,

"Never try to teach a pig to sing.
It's a waste of time, and it annoys the pig."

Save your breath!

Load Toad 23rd Apr 2012 09:55

The bloke is a troll matey - ignore the troll.

45-Shooter 23rd Apr 2012 19:59

Dyslexia???
 
Missed the "IIRC" inserted at the start of that post did you? The 660 must have been the 60+60 losses of the two raids? I do not know, but is it really that important to this topic?
Just to get back on track, how many planes do you think Bomber Command of the RAF would have lost if they sent Lancasters against those targets in broad day light? Honestly!

45-Shooter 23rd Apr 2012 21:36

What is your honest opinion of the two planes if they had been required to swap missions?
No opinion needed. The B17 was used at night by the RAF, and the Lancaster did bomb by day.
Which one had the highest losses durring the day? Right.
Lancs restricted to day light bombing for the entire war and B-17s allowed to bomb at night.
Conceivably, the Lancaster could carry several "Little Boy" weapons. Given the size of 120" x 28" and a weight of 9,000lbs you could get a couple in a standard BIII with the doors closed, and be at a comfortable 18,000lbs. What's your point?
There was no point. It was a silly argument just like many others here. But you are very wrong about the Lanc being able to carry two LBs. They were as you point out 28" wide the lanc bomb bay was not 2X28=56"wide! Plus the inter bomb space when the Lanc was barely wide enough to carry the GS WO the doors! Right. The B-17's bomb bay was wider than the Lancaster's bay.
In reality the B17 was never considered for atomic bombs, where the Lancaster was. It was the logistics that prevented it.Absolutely right!
The lancaster's bomb bay was not nearly tall enough to carry that bomb load.
Whoops. Wrong again. What carriers did the atomic bombs use? "Grand Slam" ones. Guess what aircraft they fit, and what aircraft they don't.
Whoops, wrong again! The carrier, or shackle as we say, has nothing to do with wether the bomb will fit into the plane. GS was 46" OD and barely fit, by the skin of their teeth. The FM was 68"! 60" for the bomb and 4" for the four radar proximity fuzes.
Mission may dictate how much you are required to carry - not how much you can. This is why your argument is pointless. A B17 or a Lancaster may have been ordered to carry a kettle, a cuddly toy and a fondue set, but it doesn't mean its all its capable of.
Exactly my point! To any given range, past that of the full load, the B-17 can carry more pounds of bombs than the Lancaster.
Mission planning has nothing to do with the physical capability of an aircraft.
Whoops, wrong again! Mission planning has everything to do with the physical capacity of the plane. You can not schedual a target that is beyond the planes range, or with more bombs than the plane can carry to that range, or altitude.
so that the average for all missions was ~4,500 pounds for the B-17s and ~7,800 pounds for the Lancaster. If their rolls would have been reversed, the AVERAGE bomb loads would have also been reversed!
No it wouldn't, and they weren't. Lancasters bombed in daylight to Augsburg, and then several other daylight missions later in the war. The loads stay the same, becuase the targets are still as distant, and the aircraft still flies the same regardless of if daylight or not.
Whoops, wrong again! If you are required to switch ALL of the missions, then it is a different story. You can not take heavily escorted late war examples as expressive of the entire war. Look how many Lancs that were lost on early war day time raids. That is why they had to switch to night bombing. Their losses were absolutely un-sustainable. If they had been REQUIRED to continue day light bombing, they would have HAD to add armor, guns and ammo to even try to make it work. That does not count the additional strengthening that would have been required to make the Lancaster less fragile. Remember that this is the part of the argument that you have still not addressed. What happens to average and maximum bomb load when you add the weight of armor, guns ammo and crew to use them? It goes down! So does speed, range and ceiling!

The B-17 was a little lighter empty than the Lancaster; 36,135 Lbs to 36,457 pounds EEW. Yet it carried by most estimates about 4,000 pounds more Armor, guns and ammo at that weight. Then there is the three extra crew and the weight of all their supplies. What happens to the Lancaster when you remove 4,000 plus pounds of bombs to make weight available for weapons armor and ammo? What happens when you take away 600 more pounds for the three extra crew to use those weapons?:ugh: Rich Why you're ignoring this I don't know. I'm beginning to think you have a learning disability. (Cut and past from below?)

The answer is that it does not look nearly so neet does it?:ugh:

Because load and Range are fungible, you can trade one for the other at will, over any but the shortest ranges. Because the B-17 was/is/and always will be more efficient aerodynamically, it will always win that trade off at any but the shortest ranges. Always!

So you keep saying. But I've shown you - the B17 only wins at higher altitudes. If we use the Lancaster at altitudes its happy with (16,000ft) rather than try and force it up higher, its happy to carry 22,000lbs up there for 1600 miles. PS. Where did you get this range with that load?

But you forget that altitude is also fungible!:ugh: If the B-17 were flown down low, it would carry more weight to longer ranges than the Lancaster. The more streamlined plane and better, more efficient engines do not get less stream lined and less efficient down low. ( Technically the turbos do get slightly less efficient, but not enough to make any difference in this example!)
The USAF manuals give figures for the B17 consistently less than that... 17,600lbs for 1000miles or so at 16,000ft.
With external loads. What about all internal loads of eight 2,000 pounders to 1250 miles at 20,200'? Or four 4,000 pound MC bombs to 1,310 miles at 20,500'? Why choose the worst case and beat it against the best case?
If we look at longer ranges, the B17 was down to 4,000lbs at its most stretched. By comparison the longest Lancaster missions were still carrying 9,000lbs at 2,000 miles. (East Kirkby - Munich, 630 Sqn, 1944)
Exactly when was this mission and what were the details? Depending on the exact details, I get about 660 miles each way. My math skills are limited, but that seems a lot closer to 1,320 miles than 2,000?
Why you're ignoring this I don't know. I'm beginning to think you have a learning disability.

Because of that aerodynamic advantage it will always fly higher at any given weight.

Read above. It doesn't. At comparative loads to the Lancaster, its inferior at the same altitudes. Its only superior at high altitude; and only then because the Lancaster can't get to them. Up to its ceiling the Lanc outperforms the B17 in payload and range.
Only when you site the B-17 with external loads and the Lanc with out.
These two facts are not in dispute.

They are not facts. They're your opinion. The facts are what you find in manuals, books, and real life, not in your posts - and you've been proved wrong repeatedly.
I know! I have all the realivant books. I have searched more on line and they all say the same thing. The B-17 was the more efficient plane. (At any altitude and weight!)
You keep going back to the various placard numbers, but you have never explained why the Lancaster could carry 18,000 pounds but could only AVERAGE less than 8000 pounds per mission?

Maybe the multitude There is no multitude of other missions! Mines count as bombs on the total listed. So do "Special Payloads". All of those other missions after the war do not count either. Out of the 608K Missions, exactly how many do you claim were counted in the total, but dropped no bombs?
The explanation is simple. The aircraft's capability is what it can truly carry, not what it is ordered to carry!
You are right and what it could carry to the ranges and altitudes required was about 7,800 pounds per mission. But if it had been required to operate in day light for 100% of it's missions, that would have been reduced to something much less. You tell me how much less.
On the other hand, if the B-17 had to fly 100% of it's missions at night, how much more could it have carried sans armor, guns, ammo and three crew and their supplies?

You tell me.
PS. see this link for some more realistic, but less flatering numbers. Avro Lancaster - Great Britain

longer ron 24th Apr 2012 20:46

Its a long post for a troll innit :ok:

Weheka 25th Apr 2012 05:15

"Good one! I am the first to admit that my CFS rotted brain is not the best around. I do not have a clue what I was thinking?"

Please.....say no more, and be careful with that 45.....shooter!

GQ2 27th Apr 2012 19:53

The More Telling Facts.
 
The pro's and cons of the B17 and the Lanc are obvious. When the RAF tried daylight bombing against the Luftwaffe early in the war, they soon gave it up as a bad job, except under special circumstances. The point was underlined by the Luftwaffes inability of even hundreds of fighters to defend a small force of bombers later in the BoB. When the USAAF arrived years later, they ignored the facts, - they insisted that they could defend themselves, and were roundly trounced by even the depleted Jagdwaffe. Only a large fighter force could emeliorate the losses. Later in the war, even when the Luftwaffe was on it's knees, the USAAF daylight losses were severe.
The real issue is none of the above. A Mosquito could carry a B17's load, faster, higher and usually further, for a fraction of the industrial effort. Lastly, the Mossie losses were a fraction of the four-engined heavies. The slaughter of the latter was suppressed not only during the war, but for a long time afterwards. Had the equivalent industrial effort been put into Mossies, as it was into the four-engined heavies, then the German defences would have been overwhelmed, and many aircrew lives saved.
The same entrenched views that tried to stifle the Mosquito clung to the older ideas that ensured heavy-bomber production.


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