B24 ceiling vs. B17 ceiling

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Sorry to be blunt Greg. These statements are wrong. Everything you said here is completely at odds with all wartime analysis by the scientists and statisticians for the various commands.

"Loss rates go up with time in hostile airspace" Of course it does! The longer fish are around your hooks, the greater number of fish you will catch. Put another way, the longer you fish, the more fish you will catch. Predator-prey models which have been around for over a hundred years predict this to be the outcome. These models have 5 key components: prey availability, prey density, search time, handling time and satiation. The longer prey is available to a predator (measured in units of time), the greater the likelihood it is attacked and eaten. Handling time includes the act of capture as well as consumption. Satiation is the point at which the predator no longer wishes to use energy capturing prey due to being full. The air warfare analogy to satiation is the combination of fatigue and running out of fuel.

"loss rate go up with distance" distance is a function of time, see above.

"loss rates go up with weather" poorly stated, perhaps, but aircraft crash rates absolutely went up with bad weather. Surely you aren't arguing otherwise?

Jim

Depends on circumstances.

Statisticians calculate values that have everything to do with aggregate numbers and almost nothing to do with your circumstances. Being an engineer, I should know. Statistics can be correctly calculated and still have nothing to do with your circumstances; they're just statistics that generally predict outcomes. They don't predict YOUR outcome. They only predict probability if 1) the original assumptions are correct and 2) you try the experiment MANY times randomly. After a certain number of random trials, your outcomes should generally reflect the probabilities IF 1) and 2) are correct. There is almost nothing random about a wartime aircraft mission.

So, in general, the more time you spend over enemy territory, the greater the chance you will be found and attacked ... true. But, you can seriously affect the outcome by changing the circumstances. We all know that large streams of bombers were detected and attacked with flak and fighters, sure.

Go research how many times a flight of ONE fast photo-reconnaissance aircraft was successfully found and attacked and get back with me. It isn't very often. So, sure, I'll agree with you for large formations of escorted bombers. But I disagree strongly with your contention for small formations of fighters and/or fast bombers with a specific target. They almost always got through, and were planned so they also usually got through with the element of surprise.
 
Nearly 500 out of how many, Snautzer01? You can't say much with one number.

It's like saying, "Abbey Rangers - 1" without the score for the other team. I can guarantee you their chance of getting attacked was MUCH less than for someone in a heavy bomber stream.
Quote: From its inception in 1939 through to the end of hostilities in the far East in 1945, this highly effective unit suffered horrendous losses, indeed records now show that the survival rate was proportionally the second lowest of any Allied aerial unit during the entire war. Yet these crews have never been officially
 
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Quote: From its inception in 1939 through to the end of hostilities in the far East in 1945, this highly effective unit suffered horrendous losses, indeed records now show that the survival rate was proportionally the second lowest of any Allied aerial unit during the entire war. Yet these crews have never been officially
Even without enemy action those missions were dangerous, any mechanical or navigation issue can mean you dont get back. New Mosquitos made in Canada were lost being delivered to UK, no one ever got to the bottom of the reason why there were so many. Even Leigh Mallory in an Avro York with a navigator on board managed to hit a mountain that was in the wrong place in 1944.
 
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I believe that in the Pacific, where lower altitude missions and longer ranges were more important, they pretty much switched over to the B-24 and removed the tail turret to save weight, using a tail gunner position without a turret.

The B-24 could not belly land without making a big mess, the top turret smashing down onto the pilots. A B-17 could belly land and I think you could have it up and running the next day.

Ironically, the Luftwaffe reportedly had great respect for the tail turret of the B-24. A friend of mine's father was a waist gunner on B-24's in the ETO and talked to a tail gunner who had run up an impressive score of kills. When asked how he did it the gunner replied that when he saw an enemy fighter approaching he swiveled the turret back and forth rapidly and moved the guns up and down to convey the impression that the turret was malfunctioning. Then, when the German closed in at what he thought was a a helpless target, BAM! No word if he deliberately hit the cockpit to prevent his secret technique from getting out.

The Davis wing was more efficient, but in the words of Earnest K. Gann, who flew C-87's and C-109's, "The Davis wing could not carry enough ice to chill a highball."

Some years ago I was amused and surprised to find that the B-17 has a higher service ceiling than does a C-130.
 
Lower weight 106 Squadron bomb loads:

112 x 30-lb incendiaries (3.360 lbs nominal total, consisting of 14 x 8 x 30-lb SBC) carried in late 1942 and early 1943
1,260 x 4-lb incendiaries (5,040 lbs nominal total, consisting of 14 x 90 x 4-lb SBC) carried in late 1942 and early 1943
5 x 1,000-lb bombs (5,000 lbs nominal total) carried in late 1942.
Thanks for the details, I did not think even to Italy in 1942 the loads fell that far. I went and looked at the monthly totals, average Lancaster load at night, the October page is hard to read.

Average Lancaster load at night
October 1942, 6,083 pounds, 517 sorties bombed, 726 tons HE, 677.9 tons Incendiary.
November 1942, 4,908 pounds, 602 sorties bombed, 640.2 tons HE, 679 tons Incendiary.
December 1942, 6,006 pounds, 564 sorties bombed, 620.9 tons HE, 891.3 tons Incendiary.

Average Halifax load at night
October 1942, 5,799 pounds, 332 sorties bombed, 375.8 tons HE, 483.7 tons Incendiary.
November 1942, 4,077 pounds, 262 sorties bombed, 229 tons HE, 247.9 tons Incendiary.
December 1942, 4,998 pounds, 221 sorties bombed, 200.2 tons HE, 291.9 tons Incendiary.

They were dropping many more 1,000 pound bombs than 500 pound ones, around 40% of Lancasters carrying a 4,000 pound bomb, I am wondering if there was a shortage of bombs at the time.

However, all bomber types,
October 1942, 258 night sorties attacked targets in Italy, 1,230 targets in Germany.
November 1942, 843 night sorties attacked targets in Italy, 487 targets in Germany.
December 1942, 698 night sorties attacked targets in Italy, 355 targets in Germany.

The all Lancaster force that bombed Milan by day on 24 October carried an average of 3,992 pounds of bombs, all up 51.8 tons HE 87.2 tons Incendiary. Harry Holmes in his Lancaster book noted in early 1942 the Lancaster maximum weight was 60,000 pounds, rising to 63,000 pounds by November, allowing a bigger bomb load.

The B-17 could carry 8,000 lbs internally, but this had to be 8 x 1,000-lb SAP bombs; only 6 x 1,000-lb GP bombs could fit.

According to B-17 bomb loads for the 401st Bomb Squadron of the 91st Bomb Group for Nov. 1942 through June 1944:
10 x 500-lb bombs (21.9% of sorties)
12 x 500-lb bombs (18.6% of sorties)
42 x 100-lb incendiaries (12.0% of sorties)
5 x 1,000-lb bombs (11.5% of sorties)
6 x 1,000-lb bombs (6.0% of sorties)
Many references use the 12,600 pounds of 1,600 pound AP as the B-17 and B-24 maximum internal load. Few SAP bombs were dropped by the USAAF in Europe so the HE capacity ruled. The list of bomb loads only covers 70% of sorties but averages to close to the wartime ones. The 15th Air Force Target and Duty Sheets normally give the type of bombs dropped or at least their weights, by group, but I have not done an analysis.

None of which change the losses to AAA ...and they still generally outweigh the losses to fighters except for heavy bombers, where they are about equal.
So there are no examples of flak guns causing the sorts of casualties to USAAF heavy bombers that fighters did.

I am trying to figure out if you are trying to be the comedy relief on this topic. You are aware that the most dangerous animal to humans in many countries, after humans themselves of course, is the horse, based on the number of people they kill. Or maybe local herbivores like deer when they collide with vehicles. After all sharks kill only around 70 people per year world wide. Time to send the horse and deer types extinct to reduce the risks to humans. As long as you believe death numbers have nothing to do with the number of opportunities for a fatal interaction you can go and feed the bears in the wild, they are safer, they kill fewer people each year, so do tigers, lions and even polar bears the last land carnivore that still treats humans as just meat, the other land carnivores have worked out killing apes of the hairless kind results in lots of hairless apes coming after you.

Meantime people can go look at the USAAF Statistical digest and note in 1942 the average effective 8th Air Force Heavy Bomber sortie fired about 2,272 rounds, in 1943 1,326, in 1944 236, in 1945 107, or alternatively can note of the 66,115 effective heavy bomber sorties to end May 1944 1,749 or 2.65% are listed as lost to enemy aircraft and 675 or 1.02% to flak. This represents under a quarter of total sorties flown. June 1944 to May 1945 has 208,806 sorties, 703 lost to enemy aircraft or 0.34% and 1,746 lost to flak or 0.84%. So to June 1944 the threat to the heavy bombers by fighters was 7.8 times that of the rest of the war, the threat by flak 1.2 times. The allies, mostly the USAAF, were quite successful in removing the threat of USAAF heavy bombers being intercepted for over 75% of the sorties flown.

Since we are into statistics projecting the future, continue the 2.65% loss rate to the end of the war and that is 5,533 heavy bombers, an increase of 4,830, upping total 8th Air Force losses from flak and fighters to 9,721 versus 4,891 in reality and a not quite 3 bombers lost to fighter for every one to flak.

There is almost nothing random about a wartime aircraft mission.
The plans were not random but in statistical terms there is plenty random, who is flying that day, how accurately the aircraft are being navigated/guided, what can be seen when there are some clouds around, the weather itself particularly at the target, whether decoy missions work or surprise is kept, like overflying an unexpected ship on approaching the coast. Who is higher and ahead when hostile formations come into sight, where the sun is relative to the formations and so on. Examples like which city and which part of that city was hit by the second atomic bomb. The Germans knew the USAAF was after Ploesti from radio intercepts, then came navigation errors. The first Schweinfurt timetable derailed by fog. Operation Pedestal, after leaving Gibraltar being spotted by a French airliner, which then decided to tell the world. In 1945 the low level Mosquito raid on Copenhagen, one lost so close to the target some of the formation thought the in session girl's school it crashed into was the actual target. The 17 April 1942 Augsburg raid, low level, 12 Lancasters, one formation accidentally encountered German fighters. The Hurricane pilot taking off alone in France in May 1940, flying around Sedan to see what a breakthrough looked like while listening to the BBC and then encountering hostile aircraft, but below him.

Go research how many times a flight of ONE fast photo-reconnaissance aircraft was successfully found and attacked and get back with me. It isn't very often. So, sure, I'll agree with you for large formations of escorted bombers. But I disagree strongly with your contention for small formations of fighters and/or fast bombers with a specific target. They almost always got through, and were planned so they also usually got through with the element of surprise.
Is this allied or axis interceptors? And fast is what in absolute and relative terms? To spell it out flying in a single high speed aircraft has much less chance of being fired at than one of a large formation of slower and probably lower aircraft, even if it is hostile airspace for longer than any of the formation. Compare like with like.

Have you read the history of RAF 2 Group, given its many attempts to attack targets in small formations, the times none of the Blenheims came back, the Knapsack raid on 12 August 1941, 54 Blenheims sent 10 MIA. Plenty of what were then considered fast Blenheim reconnaissance sorties did not come back in 1939/41. The ultimate WWII fast bomber was the Mosquito, in about a year of mostly low level small size day missions, 726 sent, 144 aborts, 48 MIA, 6.6% of those sent, 8.2% of those credited with attacking.

The shift in goal posts from things that effect the chances of interception to "getting through" is fun, the 1943 Schweinfurt missions got through, the USAAF B-26 mission that lost all of its aircraft might have got through, that is some of the aircraft might have bombed before being shot down.

Since you are the one saying everyone else is wrong, "Go research how many times... and get back to" us. ETO/MTO. Start with heavy bomber formations mauled by flak guns like they were mauled by fighters. The 9th Air force ran thousands of small fighter formation specific missions, on top of the armed reconnaissance ones, they almost always got through, surprise was helped by the targets usually being so close to the front line.
 
They were dropping many more 1,000 pound bombs than 500 pound ones, around 40% of Lancasters carrying a 4,000 pound bomb, I am wondering if there was a shortage of bombs at the time.

There certainly was in 1944, with the RAF having to use American SAP and GP bombs, as well as expending its own stocks of GP bombs, to make up for a shortage of MC bombs.


The all Lancaster force that bombed Milan by day on 24 October carried an average of 3,992 pounds of bombs, all up 51.8 tons HE 87.2 tons Incendiary. Harry Holmes in his Lancaster book noted in early 1942 the Lancaster maximum weight was 60,000 pounds, rising to 63,000 pounds by November, allowing a bigger bomb load.

That's certainly contributed, but I think changes to the bomb bay arrangements also helped. For example, as this image posted in an old thread shows, each row only contained three 500-lb bombs. But later on there are numerous wartime images showing each row holding four 500-lb bombs, which boosted the total carried from 14 to 18 or even 20.


Many references use the 12,600 pounds of 1,600 pound AP as the B-17 and B-24 maximum internal load. Few SAP bombs were dropped by the USAAF in Europe so the HE capacity ruled. The list of bomb loads only covers 70% of sorties but averages to close to the wartime ones. The 15th Air Force Target and Duty Sheets normally give the type of bombs dropped or at least their weights, by group, but I have not done an analysis.

The USAAF is more straightforward since HE bomb loads were usually 5,000 or 6,000 lbs. leaving the main question as to whether it was 500-lb or 1,000-lb bombs. RAF loads were incredibly varied.
 
Here is something worth reading re a summary of the USAAF analysis of the B-17 vs B-24:


edit: Whoops, I missed the post upthread by Jugman where he has already posted this document.
 

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Quote: From its inception in 1939 through to the end of hostilities in the far East in 1945, this highly effective unit suffered horrendous losses, indeed records now show that the survival rate was proportionally the second lowest of any Allied aerial unit during the entire war. Yet these crews have never been officially

Hi Snautzer01,

I see what you are posting and I don't doubt the accuracy of your research. But it makes no sense.

I have spoken with maybe 15 photo recon pilots from WWII and all said they usually had no problems unless they were flying low over heavily-defended targets. I certainly believe you'd be attacked, at least by flak and small arms, if you overflew an enemy airfield at 100 feet, but I seriously doubt the same if you were at 20,000 feet. I suppose it would depend on the mission the guys you are citing were flying. They didn't make all that many PR birds, relative to normal fighters, and a lot survived the war, so SOMETHING seems off. I just don't know what.

The main issue for analyzing it would be getting the data including mission target, number of planes sortied, altitude, and speed when photographing. Finding a source for data would help a LOT.

Cheers.
 
IIRC one cause was identified after a Canadian built Mossie limped into Prestwick with a large hole in its rear fuselage. The oxygen tanks located there had exploded in flight.
As far as I remember it was put down to lack of testing / inspection on brand new aircraft to suss out things like exploding oxygen tanks.
 
Hi Snautzer01,

I see what you are posting and I don't doubt the accuracy of your research. But it makes no sense.

I have spoken with maybe 15 photo recon pilots from WWII and all said they usually had no problems unless they were flying low over heavily-defended targets. I certainly believe you'd be attacked, at least by flak and small arms, if you overflew an enemy airfield at 100 feet, but I seriously doubt the same if you were at 20,000 feet. I suppose it would depend on the mission the guys you are citing were flying. They didn't make all that many PR birds, relative to normal fighters, and a lot survived the war, so SOMETHING seems off. I just don't know what.

The main issue for analyzing it would be getting the data including mission target, number of planes sortied, altitude, and speed when photographing. Finding a source for data would help a LOT.

Cheers.
Hi Greg. I am not an expert on this. Just found this source wich seemed to be credible. Its not my research. Food for thought and perhaps an incentive for further research.

Cheers.
 
Thanks for the details, I did not think even to Italy in 1942 the loads fell that far. I went and looked at the monthly totals, average Lancaster load at night, the October page is hard to read.

Average Lancaster load at night
October 1942, 6,083 pounds, 517 sorties bombed, 726 tons HE, 677.9 tons Incendiary.
November 1942, 4,908 pounds, 602 sorties bombed, 640.2 tons HE, 679 tons Incendiary.
December 1942, 6,006 pounds, 564 sorties bombed, 620.9 tons HE, 891.3 tons Incendiary.

Average Halifax load at night
October 1942, 5,799 pounds, 332 sorties bombed, 375.8 tons HE, 483.7 tons Incendiary.
November 1942, 4,077 pounds, 262 sorties bombed, 229 tons HE, 247.9 tons Incendiary.
December 1942, 4,998 pounds, 221 sorties bombed, 200.2 tons HE, 291.9 tons Incendiary.

They were dropping many more 1,000 pound bombs than 500 pound ones, around 40% of Lancasters carrying a 4,000 pound bomb, I am wondering if there was a shortage of bombs at the time.

However, all bomber types,
October 1942, 258 night sorties attacked targets in Italy, 1,230 targets in Germany.
November 1942, 843 night sorties attacked targets in Italy, 487 targets in Germany.
December 1942, 698 night sorties attacked targets in Italy, 355 targets in Germany.

The all Lancaster force that bombed Milan by day on 24 October carried an average of 3,992 pounds of bombs, all up 51.8 tons HE 87.2 tons Incendiary. Harry Holmes in his Lancaster book noted in early 1942 the Lancaster maximum weight was 60,000 pounds, rising to 63,000 pounds by November, allowing a bigger bomb load.


Many references use the 12,600 pounds of 1,600 pound AP as the B-17 and B-24 maximum internal load. Few SAP bombs were dropped by the USAAF in Europe so the HE capacity ruled. The list of bomb loads only covers 70% of sorties but averages to close to the wartime ones. The 15th Air Force Target and Duty Sheets normally give the type of bombs dropped or at least their weights, by group, but I have not done an analysis.


So there are no examples of flak guns causing the sorts of casualties to USAAF heavy bombers that fighters did.

I am trying to figure out if you are trying to be the comedy relief on this topic. You are aware that the most dangerous animal to humans in many countries, after humans themselves of course, is the horse, based on the number of people they kill. Or maybe local herbivores like deer when they collide with vehicles. After all sharks kill only around 70 people per year world wide. Time to send the horse and deer types extinct to reduce the risks to humans. As long as you believe death numbers have nothing to do with the number of opportunities for a fatal interaction you can go and feed the bears in the wild, they are safer, they kill fewer people each year, so do tigers, lions and even polar bears the last land carnivore that still treats humans as just meat, the other land carnivores have worked out killing apes of the hairless kind results in lots of hairless apes coming after you.

Meantime people can go look at the USAAF Statistical digest and note in 1942 the average effective 8th Air Force Heavy Bomber sortie fired about 2,272 rounds, in 1943 1,326, in 1944 236, in 1945 107, or alternatively can note of the 66,115 effective heavy bomber sorties to end May 1944 1,749 or 2.65% are listed as lost to enemy aircraft and 675 or 1.02% to flak. This represents under a quarter of total sorties flown. June 1944 to May 1945 has 208,806 sorties, 703 lost to enemy aircraft or 0.34% and 1,746 lost to flak or 0.84%. So to June 1944 the threat to the heavy bombers by fighters was 7.8 times that of the rest of the war, the threat by flak 1.2 times. The allies, mostly the USAAF, were quite successful in removing the threat of USAAF heavy bombers being intercepted for over 75% of the sorties flown.

Since we are into statistics projecting the future, continue the 2.65% loss rate to the end of the war and that is 5,533 heavy bombers, an increase of 4,830, upping total 8th Air Force losses from flak and fighters to 9,721 versus 4,891 in reality and a not quite 3 bombers lost to fighter for every one to flak.


The plans were not random but in statistical terms there is plenty random, who is flying that day, how accurately the aircraft are being navigated/guided, what can be seen when there are some clouds around, the weather itself particularly at the target, whether decoy missions work or surprise is kept, like overflying an unexpected ship on approaching the coast. Who is higher and ahead when hostile formations come into sight, where the sun is relative to the formations and so on. Examples like which city and which part of that city was hit by the second atomic bomb. The Germans knew the USAAF was after Ploesti from radio intercepts, then came navigation errors. The first Schweinfurt timetable derailed by fog. Operation Pedestal, after leaving Gibraltar being spotted by a French airliner, which then decided to tell the world. In 1945 the low level Mosquito raid on Copenhagen, one lost so close to the target some of the formation thought the in session girl's school it crashed into was the actual target. The 17 April 1942 Augsburg raid, low level, 12 Lancasters, one formation accidentally encountered German fighters. The Hurricane pilot taking off alone in France in May 1940, flying around Sedan to see what a breakthrough looked like while listening to the BBC and then encountering hostile aircraft, but below him.


Is this allied or axis interceptors? And fast is what in absolute and relative terms? To spell it out flying in a single high speed aircraft has much less chance of being fired at than one of a large formation of slower and probably lower aircraft, even if it is hostile airspace for longer than any of the formation. Compare like with like.

Have you read the history of RAF 2 Group, given its many attempts to attack targets in small formations, the times none of the Blenheims came back, the Knapsack raid on 12 August 1941, 54 Blenheims sent 10 MIA. Plenty of what were then considered fast Blenheim reconnaissance sorties did not come back in 1939/41. The ultimate WWII fast bomber was the Mosquito, in about a year of mostly low level small size day missions, 726 sent, 144 aborts, 48 MIA, 6.6% of those sent, 8.2% of those credited with attacking.

The shift in goal posts from things that effect the chances of interception to "getting through" is fun, the 1943 Schweinfurt missions got through, the USAAF B-26 mission that lost all of its aircraft might have got through, that is some of the aircraft might have bombed before being shot down.

Since you are the one saying everyone else is wrong, "Go research how many times... and get back to" us. ETO/MTO. Start with heavy bomber formations mauled by flak guns like they were mauled by fighters. The 9th Air force ran thousands of small fighter formation specific missions, on top of the armed reconnaissance ones, they almost always got through, surprise was helped by the targets usually being so close to the front
No examples of flak causing casualties like fighters? You must be looking at a different war than I am. Check the Statistical Digest of World War Two, Table 159. It's official USAAF numbers.

For heavy Bombers in the ETO, they lost 2,451 to fightgers and 2,439 to AAA (flak). For all practical purposes, those two numbers are the same (OK, 99.47% the same). They also lost 657 to other causes. So, Yes, they lost as many Heavies to flak as to fighters by the time the war ended.

In July 1944, they lost 201 to flak, 80 to fighters, and 71 to other causes, so there's your one example. In 34 months between Aug 42 and May 45, they lost more heavies to flak than to fighters in 12 of those months ... all of which were the last 12 month of the war. You can argue that the Luftwaffe was weakened in 1945, but in 1944 the Luftwaffe was putting up pretty fierce resistance. In fact, the Luftwaffe shot down more heavies in 1944 than in any other year of the war and, in 1944, they lost more heavies to flak (1,587) than to fighters (1,516).

Just in case you don't HAVE the Statistical Digest of World War Two, you can download it at:
chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/http://www.91stbombgroup.com/91st_info/army_air_forces_statistical_digest_ww2_1945.pdf

While not exactly error free (the tables were before spreadsheets were invented), it's a great primary research tool ... as long as you read between the lines and look at their definitions. Cheers.

Hey Geoffrey, your posts are generally chock full of numbers, Maybe post some of your source links, too? Cheers again. :)
 
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Hi Greg. I am not an expert on this. Just found this source wich seemed to be credible. Its not my research. Food for thought and perhaps an incentive for further research.

Cheers.

Hi Snautzer01.

No worries, I'm not exactly an expert at it either, but I do look at it frequently with an eye toward understanding the meaning behind the numbers. I like to think the guys who were there KNOW but, in reality, they only recall what their own unit was into at the time, not the overall picture.
 

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