Out of the Big Three WW2 bombers (B-17, B-24, Lancaster), was the Flying Fortress the most redundant?

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Different construction designs.

Also, the B-17 had a better ditching survivability because of the shape of the fuselage, low wing placement and a stall speed of about 80mph.
The B-24's stall speed was just about 100mph and the nose of the B-24 had the turret up high, lots of narrow framing for the Bombardier station, which would not offer much resistance when it hit the water, and that, coupled with the high wing meant the B-24 would be submerged before the main-wing offered resistance to the water as it ditched.
Couple that with the flimsy roll up bomb bay doors, which would cave in when the a/c pancaked.
 
Couple that with the flimsy roll up bomb bay doors, which would cave in when the a/c pancaked.
Makes the common joke that the B-24 was "designed as a seaplane, but Consolidated never managed to plug all the leaks" particularly topical. I think I first heard it in Martin Bowman's B-24 Combat Missions. Does certainly look like a flying boat, probably part of why I like it. Incidentally I never understood how the PB2Y, that looks like a combination of a PBY and B-24, had less range than either aircraft.

So yeah my 2 cents: all three aircraft are great and have their own flaws. If you're parachuting out, you don't want a Lanc. If you're ditching, you don't want a Lib. It would seem that the B-17 is the most balanced, it does everything relatively well, whereas the Lanc and Lib have strong advantages and strong disadvantages
 
The structure of the B-24 seems particular weak even though the empty weight is comparable tö the B-17's and Lancaster's. How come?
It wasn't 'particularly weak', but there were design related issues such as nose wheels that failed and impact related issues that were never designed for until the 1960s.
 
It wasn't 'particularly weak', but there were design related issues such as nose wheels that failed and impact related issues that were never designed for until the 1960s.
Is the nose wheel collapse only an issue because the B-24 was the only one with a nose wheel? The problems of heavily loaded tail draggers were well known but the norm at the time. For example there are no pictures of the Halifax that went off the runway here because the resulting fire and explosion of the bombload just left a hole in the ground and 4 Merlins scattered across North Yorkshire.
 
Is the nose wheel collapse only an issue because the B-24 was the only one with a nose wheel? The problems of heavily loaded tail draggers were well known but the norm at the time. For example there are no pictures of the Halifax that went off the runway here because the resulting fire and explosion of the bombload just left a hole in the ground and 4 Merlins scattered across North Yorkshire.
Good question but P-39 and P-38 also had nosewheels. The issues for B-24 design seemed rooted in the 'shimmy' experienced during high speed roll and would sem to me to depend somewhat on the attach infrastructure or even the stiffness of the Nose assembly more than the gear itself.
 
The B-17 was not designed with any particular AP bomb in mind. In fact, as far as I have been able to find there were no standard USAAC AP bombs before the early-war converted artillery projectiles. The reason the B-17 was able to carry 8x 1600 lb AP was due to the small diameter of the 1600 lb AP bomb body.
It makes for a major difference, the B-17 could carry internally under half the weight of HE versus AP. Thanks for the pre war list of bomb types, if the War Production Board is correct of the USAAF types only the 100 pound M31 was in production in July 1940 or later, the Navy 1,000, 500 and 100 pound mark IV continues production.

According to the War Production Board the wartime AP bombs entered production as follows,

January 1942, 1,600 pound AN Mk 1, 11,119 for the USAAF and 10,444 for the USN.

March 1942, 1,000 pound M32, 7,283 made.

October 1942 1,400 pound M63, 1,468 made, 1,000 pound AN Mk 33, 2,520 for Army 19,725 for Navy, 900 pound M60, 1,505 made and 800 pound M61, 2,691 made.

November 1942, 600 pound M62, 2,691 made.

All up 58,292 AP bombs January 1942 to February 1945 inclusive. Looking at the USN 14 and 12 inch shell weights in Naval Weapons of World War Two by John Campbell the AP rounds are slightly heavier than the relevant AP bombs, so whether the artillery HE shell was basis for the AP bomb.

Agreed the smaller diameters/greater density of the AP bombs meant more could fit into a given volume. So pre war the Air Corps/Army Hemisphere Defence doctrine was built around level bombing of enemy warships with HE bombs. The wartime 300 pound bomb was the M91, some were made in July 1940 and April 1941 at least, then production December 1941 to September 1942. The 100 pound AN-M30A1 (AN-M30 and M30) had some production in 1940 then series production from June 1941. The 100 pound Mark IV and Mods for the Navy was in production in 1940, finishing in May 1943.

B-17G_Bombload_Chart.jpg

Thanks for the B-17D and F bomb bay diagrams, here is the G diagram, I understand the G dropped the ability to carry a 1,600 pound bomb from shackles 20 and 41. The design useful bomb load of 2,050 pounds on the D had risen to 2,064 pounds on the G, any idea of what the definition is of design useful bomb load? It looks like the bomb bay design and volume did not change from the start but the number of shackles was doubled from the D probably to the E. The D bomb bay diagram lists maximum weight as 47,500 pounds, Roger Freeman in The B-17 Flying Fortress Story has the B-17C and D weights as 49,500 pounds for ferry, 48,500 pounds with a 4,000 pound bomb load.

The RAF listed its Fortress I/B-17C maximum bomb load as 7,400 pounds with normal at 5,000 pounds, while giving the following alternatives, 2x2,000 pound, 4x1,100 pound and 8x600 pound, which fits the B-17D diagram. Tare weight 29,620 pounds, no normal weight given, maximum overload 53,500 pounds with 7,400 pounds of bombs and 1,415 imperial gallons of fuel, maximum fuel was 2,075 gallons. The fuel loads agree with Freeman's internal and maximum figures.
The conclusion is the USAAF B-17 ended up optimised for carrying a specific AP bomb (and possibly AP bombs from the start) which carried over to the B-24.
Clearly not optimised for carrying AP from the start, but ended up so, almost like the bomb was designed for the aircraft. The B-17 maximum weight went up abut 10 short tons without increasing the bomb bay volume. The question now is why so many references choose to report the AP only bomb load, makes me wonder what the Lancaster AP only bomb load was, whether it hit weight or volume limits first.
 
Lancaster bomb load for docks, fortifications, ships etc
6x2,000lb AP plus
3x250lb or 3x500lb

The British 2,000lb has always struck me as particularly slim. Dimensions 113in long by 13.5 in diameter. So able to fit three abreast in Lancaster bomb bay. Scroll down this page for diagram
 
I think you had 2 issues with the B-24 NLG - poor design coupled with wear and tear from possible hard landings or improper landings. I think you had many low time pilots who transitioned to the "larger" B-24 who had a habit of flaring too low and putting a lot of stress on the NLG and sometimes having the NLG touchdown first. The B-24 did have a pretty high landing speed (95 mph) when compared to the B-17 and larger aircraft with NLG were just staring to become a norm. Fast forward 65 years later, I came across this article.


This is a photo of a B-24D that was flown by my kids GGF. This occurred during a training mission after V-J day and I believe they were on Saipan. As they were taxing out the MLG collapsed. I had the MCAR report somewhere, IIRC the aircraft had a little over 300 hours on it.

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Is the nose wheel collapse only an issue because the B-24 was the only one with a nose wheel? The problems of heavily loaded tail draggers were well known but the norm at the time. For example there are no pictures of the Halifax that went off the runway here because the resulting fire and explosion of the bombload just left a hole in the ground and 4 Merlins scattered across North Yorkshire.
The B-17 was one of the last bombers in USAAF service that had a conventional configuration.
 
Has anyone interviewed the pilots of the flying circuses that orbit air shows if they had flown both the B-17 and B-24 and what was their opinion of the two types?

I watched the Lancaster fly at the Abbotsford air show in 2010, and was pretty impressed with how the pilot threw it around. Mount Baker in the background.

7B5D1513-FE8A-4C78-84F7-8395F3227D80.jpeg
140B3C30-56FD-4EC3-8DF5-52118F9F8BA9.jpeg
 
Has anyone interviewed the pilots of the flying circuses that orbit air shows if they had flown both the B-17 and B-24 and what was their opinion of the two types?

I watched the Lancaster fly at the Abbotsford air show in 2010, and was pretty impressed with how the pilot threw it around. Mount Baker in the background.

View attachment 666748View attachment 666749
I previously mentioned I knew a guy that was flying both the B-17 and B-24 for the Collings Foundation. His remarks mirrored those of the Vets that flew both. Those being that the Fortress was much easier to fly, and this was all low altitude cross country and air show flying without all the combat gear / weight.
 
Good question but P-39 and P-38 also had nosewheels. The issues for B-24 design seemed rooted in the 'shimmy' experienced during high speed roll and would sem to me to depend somewhat on the attach infrastructure or even the stiffness of the Nose assembly more than the gear itself.
I wasnt discussing facts as much as perception of facts. The P-39 had problems with the nose wheel at the start (things happen) but the late war tail draggers were very hairy on take of and landing, this was not perceived as a problem with having a tail wheel more an attitude of "it goes with the territory"
 
I wasnt discussing facts as much as perception of facts. The P-39 had problems with the nose wheel at the start (things happen) but the late war tail draggers were very hairy on take of and landing, this was not perceived as a problem with having a tail wheel more an attitude of "it goes with the territory"
And this is the reason why taildraggers went away on the majority of aircraft produced after WW2, especially on military aircraft.

You "fly" a taildragger the minute the engine(s) start turning.

I was on a program where you had USAF IPs with minimal or no tail wheel time attempt to fly a motorized tail dragger glider. Many ground loops and damaged aircraft, thank god no one was killed. A bird Colonel saw the light and killed the program.
 
Hey Geoffrey Sinclair,

re "The design useful bomb load of 2,050 pounds on the D had risen to 2,064 pounds on the G, any idea of what the definition is of design useful bomb load?"

The nominal meaning of the "design useful bomb load" is pretty much the same as the requirement to carry a specific weight of wombs to a given distance. Similar in idea to the requirement that a the Air Ministry Specification resulting in the Fairey Battle required it to carry 1000 lbs to a radius of X miles.

I do not remember for sure, but I think the requirement for the B-17C was to be able to carry ~2000 lbs of bombs over a radius of 1000 miles with max fixed tankage internal fuel of 1700 USgal.

re "The question now is why so many references choose to report the AP only bomb load, . . ."

I think it is mostly to make the B-17 not look anemic compared to the British 4-engine heavies. If you do not use the 1600 lb AP bomb load, for the US normal operations it only carried a max of ~6000 lbs, not because it did not have the poser to lift more, but because the war-time series bomb bay only had room for a max of 6x1000 lb or 12x 500 lb for a total of 6000 lbs. Rather small compared to the lightest bomb load of the RAF heavies which was the Halifax B Mk I at 9x 1000 lb (fuselage bomb bay) + 6x 500 lb (wing bays) for a total of 12,000 lbs.
 
You may have something there.
You can actually find some accounts or even manuals that will list not only the 12,800lb internal bomb load but a max bomb load of 17,600lbs.
A pair of 4000lb bombs (American not British cookie) under the wings and six 1600lb AP bombs inside.
And again it is a total useless load except for bombing an entire city, assuming the B17 when so loaded could even make it past Dunkirk and make it back to England without running out of fuel.
The American 4000lb bomb was short and fat and wasn't going to land anywhere near where the 1600lb AP bombs were going to land.
And unless the target was the already motioned thick steel or a number of feet of concrete a normal 500lb bomb held more explosive.
A B-17 on normal structures would do more damage with eight 500LB bombs than with eight 1600lb bombs.

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4000lb bomb on the right.
flying the B-17 with a pair of those metal parachutes hanging off the wings didn't do anything for the speed and range either.

However in 1940-41 there wasn't a big need to exaggerate the B-17s load because British 4 engine bombers were just trickling into service (like the B-17) and the British twin engine heavies couldn't carry much either. A 1940 Wellington with Pegasus engines didn't carry what a 1943 Wellington with Hercules engines did.
 

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