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

[ThomasP]

A basic comparison of the B-17E vs the B-24D, dated 30 May 1942, can be found here on the WWII Aircraft Performance website:

"http://www.wwiiaircraftperformance.org/B-17/B-17E_B-24D_Comparison.pdf"

As mentioned above it is from May 1942, so may not be as representative of the later war aircraft or operating conditions, but at least it gives us a base to go from.

Service Ceilings were within 1500 ft at the same weight, in favor of the B-17.
Ranges with the same fuel load at the same TOGW, in favor of the B-17E by about 150- 300 miles.
Cruise Speeds for the ranges given were in favor of the B-24D by about 2-8 mph TAS.

The most significant difference in performance is in the area of TO & Landing runs, where the B-24D runs are clearly shorter by several hundred feet
(although the tests were at very light weights of ~40,000 lbs).

Late-war, with a 3500 lb bomb load, the UK Aircraft Data Sheets show approximately the same range difference of 300 miles in favor of the B-17, and approximately the same speed advantage of 10 mph TAS at most economical cruise in favor of the B-24.

 

[SaparotRob]

Go Boeing!

 

[Howard Gibson]

The Avro Lancaster could be modified to deliver the Dam Buster bouncing bomb as well as the Tall Boy, which was used to sink the battleship Tirpitz, and the Grand Slam to destroy U-boat bunkers. This was possible because of its cavernous bomb bay.

The B-24 Liberator was known for its long range enabling it to engage targets out of reach of the other heavy bombers. It closed the Atlantic Gap which contributed to turn the tide in this war theater in the Allies' favor and it could attack the Romanian oilfields of Ploesti from bases as far as North Africa. For the same reason it replaced the B-17 to cover the vast ranges of the Pacific.

The B-17 had the advantage of being able to drop its bombload from greater heights than the other two and it was a bit more rugged although its loss rate was about the same as the Liberator's. In the end the B-24 could do the same strategic bombing missions as the Fortress.
The Lib could also be produced more easily and faster being optimized for mass production.

So could one say that the B-17 could have been done without?

The Lancaster is not comparable to the B-17 and B-24 as it did not fly the same missions and it did not face the same threats. If the Lanc were going to fly daylight bombing missions, it would have needed the two-stage Merlin engines to get it up well above 20,000ft, and it would have needed all sorts of armour and heavier defensive armament. The increased weight means a reduced bomb load. The Lancasters that carried the 22,000lb Grand Slam bombs were specially modified, with the twin .303" top turret being removed, along other things. These were flown in daylight, but they were heavily escorted, and the USAAF had killed off most of the experienced Luftwaffe pilots by that time. According to my Green and Swandborough Fact File, a Lancaster's normal bomb load was 12,000 to 14,000lb.

Could you throw a B-17 or B-24 around like you could a Lancaster? This helped them evade German night fighters. Lancasters would have benefited from some form of ventral gun position. The Lancaster's manoeuvrability and handling would have been useless in the USAAF's daylight box formations.

There is a nifty article on the B-24s in an old Wings magazine by Lin Hendricks. I posted a summary of this onto Wikipedia's B-24 page. Hendricks, later a test pilot with Republic, liked the B-24, although he noted problems. The B-24 carried a heavier bomb load than the B-17, and it flew lower, making it more accessible and attractive to the Luftwaffe.

Hendricks also noted that the B-24 leaked fuel. They flew the with bomb doors slightly ajar. Hendricks, a smoker, did not permit smoking on his B-24. The book Whiz Kids by John A. Byrne, is all about the USAAF systems analysts who took over Ford Motor company in the 1950s, led by "Tex" Thornton and Robert McNamara. Thornton, a chain smoker, flew across the Atlantic in a B-24, and he was not permitted to smoke. His team quickly demonstrated that the B-24 was not suitable for strategic bombing over Germany.

 

[FLYBOYJ]

Hendricks also noted that the B-24 leaked fuel. They flew the with bomb doors slightly ajar. Hendricks, a smoker, did not permit smoking on his B-24. The book Whiz Kids by John A. Byrne, is all about the USAAF systems analysts who took over Ford Motor company in the 1950s, led by "Tex" Thornton and Robert McNamara. Thornton, a chain smoker, flew across the Atlantic in a B-24, and he was not permitted to smoke. His team quickly demonstrated that the B-24 was not suitable for strategic bombing over Germany.

As mentioned, I had an uncle who was a B-24 FE and he said the same thing about the B-24 leaking fuel. From what I have read over the years, this was due to some rubber fittings used during assembly and sometimes maintenance crews would either replace these fittings or continually inspect and replace them as required. It seems the B-24 also had hydraulic leaks as well.

 

[SaparotRob]

I was just looking at the RAF B-17C/D (don't gimme' none of that "MK" foolishness) in Snautzer01's Boeing B-17 thread. I know the RAF used them and the B-17 wasn't up to snuff. Things didn't work well high up. There were too few of them for mutually defensive fire, etc. At the snapshot of time the photo was taken, how did the B-17 compare to the heavy bombers of other air forces?

 

[33k in the air]

The Lancasters that carried the 22,000lb Grand Slam bombs were specially modified, with the twin .303" top turret being removed, along other things. These were flown in daylight, but they were heavily escorted, and the USAAF had killed off most of the experienced Luftwaffe pilots by that time. According to my Green and Swandborough Fact File, a Lancaster's normal bomb load was 12,000 to 14,000lb.

433 Squadron few the Lancaster from Feb. 1, 1945, to the end of the war, a total of 317 bombing sorties. The weighted average nominal bomb load was 9,982 lbs. The most common specific load was 1 x 4,000-lb, 12 x 500-lb, and 4 x 250-lb (11,000 lbs nominal total), which accounted for 13.25% of the bombing sorties. After that came 1 x 4,000-lb, 10 x 500-lb, and 6 x 250-lb (11.04%). Next was 1 x 4,000-lb and 1,584 x 4-lb incendiaries (10.73%), followed by 1 x 4,000-lb and 1,500 x 4-lb incendiaries (10.09%), with 1 x 4,000-lb, 5 x 500-lb, and 4 x 250-lb (6.62%) rounding out the top five. (Incendiaries were part of the bomb load in 41% of the bombing sorties, with high explosive only loads comprising 59%.)

The squadron flew the following daytime bombing missions:

Feb. 27, 1945, against Mainz (aircraft up by 12:48 pm)
Mar. 1, 1945, against Mannheim (aircraft up by 12:05 pm)
Mar. 2, 1945, against Cologne (aircraft up by 7:34 am)
Mar. 11, 1945, against Essen (aircraft up by 11:42 am)
Mar. 12, 1945, against Dortmund (aircraft up by 12:48 pm)
Mar. 22, 1945, against Hildesheim (aircraft up by 10:56 am)
Mar. 24, 1945, against Bottrop (aircraft up by 1:07 pm)
Mar. 25, 1945, against Hanover (aircraft up by 6:19 am)
Mar. 31, 1945, against Leipzig (aircraft up by 1:39 pm)
Apr. 25, 1945, against Wangerooge (aircraft up by 2:54 pm)

 

[EwenS]

The Lancaster is not comparable to the B-17 and B-24 as it did not fly the same missions and it did not face the same threats. If the Lanc were going to fly daylight bombing missions, it would have needed the two-stage Merlin engines to get it up well above 20,000ft, and it would have needed all sorts of armour and heavier defensive armament. The increased weight means a reduced bomb load. The Lancasters that carried the 22,000lb Grand Slam bombs were specially modified, with the twin .303" top turret being removed, along other things. These were flown in daylight, but they were heavily escorted, and the USAAF had killed off most of the experienced Luftwaffe pilots by that time. According to my Green and Swandborough Fact File, a Lancaster's normal bomb load was 12,000 to 14,000lb.

Could you throw a B-17 or B-24 around like you could a Lancaster? This helped them evade German night fighters. Lancasters would have benefited from some form of ventral gun position. The Lancaster's manoeuvrability and handling would have been useless in the USAAF's daylight box formations.

I posted this up on another thread a few weeks ago but in the light of the above it is worthwhile repeating. RAF Bomber Command flew 153 daylight raids between 27 Aug 1944 and 24 April 1945 (now corrected) with the RAF increasing the numbers of Mustang squadrons allocated to escort them from 4 to 15 over that period.

https://scholars.wlu.ca/cgi/viewcontent.cgi?article=1433&context=cmh

The tight USAAF defensive box formations were not adopted due to the amount of retraining that would have been required, time that could not be afforded. Instead looser formations, referred to as a "gaggle" and containing 40-70 aircraft each, was adopted.

Lancasters were not re-engined to be able to fly these daylight sorties. But from around this time new tail turrets began to appear in both Lancaster and Halifax aircraft containing 2x0.5" MG. And from around Oct 1944 Canadian produced Lancaster X began to receive Martin mid-upper turrets with 2x0.5" which were mounted about 5 feet forward of the usual mid-upper turret position, but how many reached operational squadrons by the end of the war I'm not clear about.

Details of typical Lancaster bomb loads can be found here

Bomb Loads

Lancaster Archive

www.lancaster-archive.com

But these typical loads would be subject to variation dependent on a number of factors, including how much fuel needed to be carried for particular missions.

Another feature arising from these daylight raids was bright tail markings for G-H bombing leaders in these "gaggle" formations

GH-Tail Markings

Lancaster Archive

www.lancaster-archive.com

 

[spicmart]

His team quickly demonstrated that the B-24 was not suitable for strategic bombing over Germany.

How would they do that exactly and were the results viable?

 

[JDCAVE]

I posted this up on another thread a few weeks ago but in the light of the above it is worthwhile repeating. RAF Bomber Command flew 153 daylight raids between 27 Aug 1944 and 24 April 1944…

Ewen pretty much sums the activities by Bomber Command during the latter months of the war. You have the incorrect year in your first sentence, 24 April 1944 should be 1945. A couple of comments.

I'm uncertain how many of the modified rear turrets equipped the 6-Group squadrons. Lancaster X's with the GM 250 MUT were operational at least since the beginning of March 1945. I believe beginning with KB860, the Lanc X's had the GM turret. I'm moving right now and my lanc books are packed in a box so cannot check this. Dad's KB.865 had this turret. It was brand new when he first flew it to Mainz, March 1, 1945.

Note that the bomb loads for a given raid within a squadron for Merlin 38 and 224 a/c in 6-Group were the same right through to the end of the war, although the Air Ministry had approved a higher all-up weight for the 18-Boost a/c.

I cannot comment on the relative performance of the Liberator vs the Fortress, except dad said the B-24 handled like a cow. Dad never flew the Fortress, but he liked the lanc.

One comment: if attacked by fighters, during daylight gaggle operations, 6-Group pilots were permitted to take evasive action, I.e. the corkscrew manouevre. I don't believe USAAF pilots took evasive action in this circumstance, but I stand to be corrected if that was the case.

Jim

 

[Howard Gibson]

How would they do that exactly and were the results viable?

Good question. The author did not go into details. I have just seen a photograph of a Liberator flying missions in March 1945..

Note how pissed off the boss was, although he had a point. You can ban smoking in your Liberator. It's too bad you cannot ban the Luftwaffe from using 30mm cannons.

 

[NTGray]

The poor Halifax gets left out, again.

Not sure why it got skipped. It was produced in numbers comparable to the Lanc (just over 6,000, compared to 7,000), and carried about the same weight in bombs. So it seems like there were a Big Four.

 

[pbehn]

I was just looking at the RAF B-17C/D (don't gimme' none of that "MK" foolishness) in Snautzer01's Boeing B-17 thread. I know the RAF used them and the B-17 wasn't up to snuff. Things didn't work well high up. There were too few of them for mutually defensive fire, etc. At the snapshot of time the photo was taken, how did the B-17 compare to the heavy bombers of other air forces?

Massively better because there werent any others at that time. The Stirling had just been introduced as a night bomber, same with the Halifax, the B-17 was use by the British before the Lancaster (but not the Manchester), The LW never got the He 177 to work properly. Things didnt work out because at the time it wasnt sorted, but the basic theory was flawed, it couldnt fly high enough or fast enough to be immune to enemy defences and the argument about insufficient numbers for mutual defence was just theory, there would never be enough for mutual defence, as shown later in 1943.

 

[gruad]

The poor Halifax gets left out, again.

WW2 myth is Lanc and Hx were comparible and the B17 aced it over the B24, when the reverse was true.

Hx given lesser bomb load and better position in the stream to even the chances for the crews. Lanc easier to make and repair too.

B24 more versatile but B17 better outright day bomber and tougher.

 

[Shortround6]

For both the B-17 and the B-24 massive building programs were started (much like the British) before they had any real idea of of how either one would actually work in service.

 

[ThomasP]

And as far as the Halifax vs the Lancaster goes - if the Lancaster had not been built (ie the Manchester had overcome its teething problems early on) everyone would be singing praises to the Halifax.

 

[spicmart]

Good question. The author did not go into details. I have just seen a photograph of a Liberator flying missions in March 1945..

Note how pissed off the boss was, although he had a point. You can ban smoking in your Liberator. It's too bad you cannot ban the Luftwaffe from using 30mm cannons.

Sir Winston Churchill had a B-24 as his personal transport. So it couldn't be that bad one might assume.
How did they solve the fume problem in that?

I thought the fume issue wasn't found in all Liberators.

 

[EwenS]

Hendricks also noted that the B-24 leaked fuel. They flew the with bomb doors slightly ajar. Hendricks, a smoker, did not permit smoking on his B-24. The book Whiz Kids by John A. Byrne, is all about the USAAF systems analysts who took over Ford Motor company in the 1950s, led by "Tex" Thornton and Robert McNamara. Thornton, a chain smoker, flew across the Atlantic in a B-24, and he was not permitted to smoke. His team quickly demonstrated that the B-24 was not suitable for strategic bombing over Germany.

The fuel system varied a bit in the early aircraft but from the B-24D there were 12 main fuel tanks spread across the wing and upper fuselage between the inner engines. The fuel transfer system with all its pipework was located above that in the top of the fuselage. So if there were any petrol fumes they had direct access to the fuselage. Those tanks held 2,343 US gals. Part way through B-24D production more fuel was crammed into the wings outboard of the undercart behind the outboard engines. 3 tanks with another 225 gals each side. Finally for ferry trips and in aircraft used by the USN and RAF maritime squadrons another 1 or 2 tanks could be placed in the forward bomb bay. Each contained another 395 gals of petrol. So anything up to 3,593 US gals of highly inflammable fuel mostly centred around the inner wing and fuselage with all the associated pipework to connect them up and pumps to move it around.

With all that fuel I'm not sure that smoking would be good for your longevity! Having said that I don't recall reading of fuel leaks being a problem for the RAF in operational service. It certainly raises questions about the standard of maintenance of the aircraft.

In the B-17 the only fuel that was placed in the fuselage was in the so called ferry tanks that were also used by RAF Coastal Command B-17s. So from a design standpoint it is less likely that fumes could seep into the fuselage in the first place.

Incidentally, Churchill's Liberator AL504 "Commando" had two lives. When he used it in 1942/43 it was a twin tailed converted LB-30, little changed from the basic aircraft. In August 1943 it was flown to the Tucson Modification centre from where it emerged in April 1944 with a stretched fuselage, single tail and "luxury" 20 passenger configuration taking in the whole bomb bay. This is what appears in most photos of the aircraft. By mid-1943 the third Avro York to be built, LV633 "Ascalon", was converted as a VVIP aircraft for use by King George VI and Churchill. Then in Nov 1944 the US donated a C-54D Skymaster I in VIP form for Churchill's use.

 

[FLYBOYJ]

With all that fuel I'm not sure that smoking would be good for your longevity! Having said that I don't recall reading of fuel leaks being a problem for the RAF in operational service. It certainly raises questions about the standard of maintenance of the aircraft.

It doesn't mean this situation didn't exist. Several things to explore: One also has to look at what the RAF ordered within their B-24s. Did they have the same fuel and hydraulic fittings as aircraft produced for the US? Did the RAF perform better maintenance? Did the RAF Liberators fly less hours than the US B-24s? All factors...

 

[NTGray]

Incidentally, Churchill's Liberator AL504 "Commando" had two lives. When he used it in 1942/43 it was a twin tailed converted LB-30, little changed from the basic aircraft. In August 1943 it was flown to the Tucson Modification centre from where it emerged in April 1944 with a stretched fuselage, single tail and "luxury" 20 passenger configuration taking in the whole bomb bay. This is what appears in most photos of the aircraft. By mid-1943 the third Avro York to be built, LV633 "Ascalon", was converted as a VVIP aircraft for use by King George VI and Churchill. Then in Nov 1944 the US donated a C-54D Skymaster I in VIP form for Churchill's use.

I just did some quick reading about the Commando, and after Churchill began using the Ascalan he never again flew in the Commando. Which was good, because the Commando was lost for unknown reasons on March 27, 1945, while ferrying some lesser British dignitaries to an event in Canada. Radio contact was lost and it was never heard from again, leaving behind some small bits of wreckage and an oil slick not far from the Azores, close to its intended flight path.

 

[spicmart]

Did the B-24 have a higher total loss of non--combat crashes than the B-17 and to what percentage?