What destroyed a lot of B-17s?

[old man emu]

Supposedly the greatest bomber of WWII, if one is to believe the American propaganda, the B-17 was indeed a flying fortress. Actually, it was an inefficient tool requiring 10 crew to deliver 4800 lbs of bombs. The Lancaster, with a crew of 7 delivered 14,000 lbs and the Wooden Wonder had a crew of 2 to deliver 4000 lbs. However, what it lacked in carrying capacity it made up for in numbers.

 

Unfortunately, many B-17s were lost, not to enemy fire, but to Murphy's Law. If something can go wrong, it will  at the most inconvenient time. The B-17 was built with the cause of its own destruction.

 

[kgwilson]

It was indeed a flying fortress bristling with guns but the engines were unreliable and the bomb load poor for such a large aircraft. It originally went into service with the RAF but losses saw them withdraw it from daylight service due to it's poor performance. The USAAF though continued with daylight use in 1942 & the later models improved in performance and bomb load but they flew at 35,000 feet & bombing was hopelessly inaccurate until they got a better bomb sight in the E model. There were more improvements with the F model but their losses to German fighters saw them withdrawn from service until the P51 & P47s were able to provide fighter escort in early 1944. In October 1943 alone, 176 (1760 men) were lost. Once they got fighter escort the losses reduced. It was only the American mass production war machine that enabled replacements to exceed losses.

 

With the wing spar in the middle of the fuselage bomb capacity was severely limited. With its high wing configuration, the Avro Lancaster excelled in Bomb capacity with the added benefit of 4 RR Merlin engines. I wonder how Boeing got the contract for something that didn't seem that suited to it main purpose as a heavy bomber. The RAF issued specifications for what it needed & one of these was for the P51 Mustang which was a superb fighter (once they put the RR Merlin in it) with very long range. I suspect like most American corporate deals it was all about price over capability.

[facthunter]

The Wright 1820 is a reliable engine.  At 35,000 feet the OAT is about minus 50 . I think you would have a lot of problems with  liquid cooled Merlins at that level and Aircooled radials are much  better at  remaining operating under fire . That's an accepted fact.. USA top brass reckoned without this plane they wouldn't have  won the war in Europe. It was essential to damage German Production and lower morale by bringing the war to Germany.  Nev

[old man emu]

The bomb load capacity of the B-17 -v- the Lancaster might well be a product of the development of the two aircraft. The B-17 was basically started on a blank sheet of paper, although it was an entry into a Government military aircraft acquisition competition. It's closest predecessor was the Boeing 247, a twin-engined 10-passenger + 2 crew airliner. The Lancaster, on the other hand, evolved through a number of high wing, multi-engined from the Avro 642 Eighteen through the Manchester. This allowed the Avro simply to enlarge proven designs. Also the British had aircraft from other makers such as Vickers and Short Bros who were producing multi-engined aircraft early in the 1930's.

 

 

[onetrack]

There's another couple of angles to look at. Even though the B-17 may have had its flaws, these were often as a result of the sheer complexity of the aircraft. Another factor is the gung-ho personality attitude of many American military personnel.

 

The British and Australian military personnel are generally far more cautious, when it come to taking calculated risks. Not so the Americans, who often have a "barrel through with all guns blazing, and to hell with the risks", attitude.

 

Then there's the angle of Luftwaffe aircraft major failings. These all relate back to flawed Nazi logic from Day One, and the wrong people in charge of major decision-making. The push by the Nazis to produce as many aircraft as possible from components manufactured, meant that there were very little by way of spares - which meant cannibalisation of other working Luftwaffe aircraft, that often were laid up for minor spares requirements, that weren't available.

 

This reduced available flying Luftwaffe aircraft by a considerable percentage, and which caused constant complaints by senior Luftwaffe officers in the field - which were largely ignored.

 

Then, finally, there was the reliability of Luftwaffe aircraft which was seriously impacted by poor QC, assembly by unskilled workers, (as highly qualified technically-skilled employees were all drafted into military conscription!), and a shortage of high-tech tools and measuring equipment.

And the final nail in the coffin was the use of forced labour to manufacture and assemble Luftwaffe aircraft - highlighted by the Budzyn Polish aircraft factory, positioned to be out of reach of Allied bombers - which never produced a flyable aircraft in its 15 months of operation!

It got so bad for the Lutwaffe, that warning notices were posted on new aircraft to Luftwaffe pilots, that extreme care had to be taken in the initial use of new aircraft guns and engines, as neither had been properly tested!

The QC got so bad, the Luftwaffe ended up having to strip new aircraft to check every important component, for manufacturing quality and sabotage!

 

Numerous Luftwaffe aircraft had major components such as spars fail, because there was no accurate calibration equipment available for heat-treatment ovens and heat-treated items often had faulty heat-treatment.

There's a fascinating article (a thesis, actually), by a senior American military officer, outlining the major failures in the Nazi aircraft manufacturing system, which led to their rapid downfall, in the link below (a downloadable PDF document).

 

https://www.hsdl.org/?view&did=830366

[facthunter]

The  B-17 is a pretty conventional (as it turned out) straightforward  all metal plane of moderate AUW 65,000 lbs, that looks normal for a bomber or airliner. It's a high altitude thing which breaks a few boundaries for the period. Multiple turbo charged engines for instance. Apparently pilot's also liked  it  (a good sign) whereas the very mass produced Liberator had many handling and structural flaws that were never corrected due to the desire to keep them all the  same for simplicity of servicing and training.. US built aircraft were always simpler to service and repair and had more comfortable cockpits  which were not much more than afterthoughts on many British service aircraft.  Nev

[APenNameAndThatA]

One theory is that the Americans bombed in daylight to down enemy fighters and thereby make the invasion easier. 

[facthunter]

They certainly "pushed" the daylight bombing policy. Nev

[old man emu]

The British started the war with daylight bombing, but lacking escort fighters with enough range to give full protection, they were savaged by the Luftwaffe, so changed to night time bombing. In the early part of the war, the Germans had the superiority in fighter aircraft as well as anti-aircraft batteries coverage. There must have been an agreement that the British would keep up their night raids and the USAAF would raid during the day.

 

It wasn't until January 1943 that the USAAF carried out its first raid to Germany. On January 27, 1943, the 8th Air Force sent 64 planes from their base in England in what would be the first U.S. bombing of Germany. Both B-24 bombers and B-17 Flying Fortresses, known for their ability to take heavy fire, began their raid on the German port of Wilhelmshaven. Fifty-three planes managed to hit their targets and shot down 22 German planes. The raid was considered a success, doing significant damage to the infrastructure at Wilhemshaven while only losing three U.S. bombers in the process. 

 

It was not until the introduction of the Lockheed P-38 Lightning and Republic P-47 Thunderbolt fighters that the bombing raids could claim a measure of success. Able to carry large Lockheed-designed drop tanks, the fighters were able to escort the bombers for much of their missions. The first Allied fighters over Berlin were 55th Fighter Group P-38s on March 3, 1944. When the Merlin-powered North American P-51 Mustang was introduced in late 1943, with a laminar-flow wing for efficiency, the final escort fighter development of the war was complete.

 

 

[kgwilson]

 

There is a good historical summary of the the Unescorted daylight bombing strategy of the US 8th airforce HERE Losses and the development of long range fighter escorts changed all that.

[facthunter]

The B 17 has a pretty high cruise speed as well as a high altitude capability. Up there you usually leave contrails which are easy to spot.  Nev

[Jim McDowall]

On 13/12/2020 at 12:28 PM, kgwilson said:

I suspect like most American corporate deals it was all about price over capability.

Or perhaps, political influence? After all it is said that Earl Mountbatten influenced the Australian Govt to purchase the F111 over the TSR2 thus assisting in the killing off of the TSR project. These things happen.

[Old Koreelah]

17 hours ago, facthunter said:

The B 17 has a pretty high cruise speed as well as a high altitude capability. Up there you usually leave contrails which are easy to spot.  Nev

A former Luftwaffe pilot I knew described often seeing the contrails of Allied bomber formations returning from daylight raids. They had a habit of deviating far north of track to be within range of neutral Sweden in case they were hit.

[onetrack]

An old Dutchman I knew, who worked in the fields of Holland during the War, told me many years ago, of the sight of the sky becoming just absolutely filled with American bombers, as each daily bombing raid was carried out.

He told me, "they would come over in a huge wave in the morning, almost darkening the sky! - then they'd return later in the day, doing the same thing! It was absolutely staggering to us on the ground, to see that sight!"

A sight like that (anywhere from 700 to 1000 bombers) would no doubt, also be very frightening to any Luftwaffe pilot, particularly knowing how heavily armed the American aircraft were.

 

The major area of dispute in air war tactics, of course, between the British and Americans, was that the British decided that daylight bombing was far too dangerous, and restricted the RAF to night-time bombing only.

General Carl Spaatz, one of the leading promoters of the tactical bombing strategy of the Americans, was forthright in demanding that only daylight bombing raids would have the required level of success.

So the Americans bombed only in daylight, and the British bombed only at night. I have never seen comparative figures, but I would reckon the RAF incurred lower aircraft losses, at the expense of less effective bombing - and the Americans incurred more aircraft losses, but with the advantage of hitting more targets - simply due to better visibility.

 

But the sole factor that reduced American bomber losses more than anything, was when Gen Doolittle, with Spaatz's approval, arranged to have the American fighters leave their protective position around bombers, and adopt a far more aggressive approach, by flying ahead of the bombers and attacking the Luftwaffe, before the bombers arrived. This lead to consternation amongst bomber crews that they were being abandoned - but the results showed the effectiveness of the tactic. Bomber losses went down as soon as the strategy was adopted.

In addition, the fighters, particularly the P-51's with their superior fuel reserves, hung around until after the bombing, and kept attacking the Luftwaffe aircraft, shooting them down as they were landing, due to fuel exhaustion.

By far the single factor that improved the bombers chances of survival was the later fighters with their improved range and fuel reserves. So many times, in earlier bombing raids, the fighters had to leave early, as they were running low on fuel.

 

https://www.historynet.com/carl-a-spaatz-an-air-power-strategist.htm

[old man emu]

Can you imagine living in East Anglia during the middle to end of WWII? Many days per week masses of USAAF four-engined bombers would be forming up over that area. Imagine the noise of 400 big radial engines fitted to 100 bombers taking off from one airfield to join other groups of 100 before heading off across the channel. Then at night, further north in Lincolnshire, the roar of hundreds of Merlin engines as the RAF set off on raids.

 

https://mediafiles.thedms.co.uk/publication/ee-eet/cms/pdf/information-sheets/USAAF Airfields Guide and Map.pdf 

[F10]

The B24 was on paper, technically a better aircraft having the Davis laminar flow wing. Trouble is, it didn’t work too well as being at height on the ground, it was difficult to keep clean, disrupting laminar flow. Also if high and heavy, you had to fly at a high angle of attack, which negated the good aerodynamic laminar flow characteristics of that long tapered Davis wing. But the B24 came into its own in the Pacific theatre, where long range and a good bomb load made it the preferred type. It also suffered from poor directional stability at height, surprising considering those huge twin fins. The Venetian blind type bomb doors were also an innovative feature. It had Pratt’s as-well, a better engine I dare say, than the Wright Cyclones of the 17. Always feel a bit sorry for the old 24, bit of an ugly duckling and to me hasn’t really got the recognition it probably deserved. It’s another Hurricane/Spitfire story!

Edited May 1, 2022 by F10

[Old Koreelah]

Those of us raised on WWII movies saw lots of B-17s but no 24s, propably because that’s what was available to the movie-makers after the war. Even Jimmy Shtewart, in 12-O’Clock High flew 17s, although during the war he was a Liberator pilot.

[Student Pilot]

The biggest percentage of losses was due to training/operational accidents, the Yanks seemed worse than other Air forces

[kgwilson]

US aircraft losses were staggering during WWII. 22,948 were lost in combat but 42,216 were lost in accidents, 21,583 were lost in the US and 20,633 overseas. More than 15,000 airmen were killed in aircrew training in the US. The B-24 was nicknamed the “flying coffin” due to its many problems. Not surprisingly, more trainees died in B-24s than any other plane.

[Student Pilot]

Aircraft, they are aircraft.....................plane is what you shave wood with 😁

[onetrack]

But ... in America, they're an air plane!  

[kgwilson]

And it seems to be changing here as well. Aeroplane was the original term even in the US in the early 20th century. Why they changed to call them airplanes is typical of an Americanisation without any consideration of the meaning of a word. There are aeronautics and aeronautical and aerospace engineers and there are aerobatics, aerodromes and aero clubs. I have not heard of airnautics, airspace or air engineer (maybe pneumatic) airbatics, airdromes or air clubs so why the dumb and lazy spelling? Now not only in America.

[rgmwa]

Even the ABC newsreaders say airplane. It's only semantics, but still grates. On the other hand `aerocraft' would sound a bit odd. 

[Old Koreelah]

This creeping Americanisation of our language sure upsets me (although I’ll use the odd sensible word like thru.)

As long as Auntie doesn’t start saying aircrafts!

 

[Old Koreelah]

It’s well known that American mass production was a major factor in winning the war. Strangley, Germany didn’t fully mobilise their population and introduce round-the-clock production intill late in the war, when it was too late to keep up with the thousands of aeroplanes being built in America, where women were a major component of the workforce.

This lady was the PR pin-up girl: