whats up with the 4 engines.

[Furball]

Oh... and slightly off topic but quite interesting anyway - it seems that most of the Bomber Command crews I have spoken to about it, preferred the Halifax and Wellington to the Lanc because they were much easier to get out of in the event of an emergency.

[Karnak]

Oh... and slightly off topic but quite interesting anyway - it seems that most of the Bomber Command crews I have spoken to about it, preferred the Halifax and Wellington to the Lanc because they were much easier to get out of in the event of a bale out.

The Bomber Command numbers I have seen suggested that crew had about a 33% better chance to get out of a Halifax than they did out of a Lancaster, but that the Lancaster had about a 33% lower loss rate per sortie.

[Shiva]

EDIT: Consider the B-17 had a much heavier max bombload than it carried. It was between 12000 lbs and 17000lbs if I recall. The choice for a lighter load was a decision made, not a restriction. So while I'd go with "damage" to answer your question, it doesn't rule out "loaded weight" either.

Internal ordnance on the B-17 F/G was normally 2-2000, 2-1600, 2-1000, 12-500, 16-300, 16-250, or 24-100 (from AN-01-1B-40 B-17 weight and balance, Army Manual 1943). But the lighter bombload was a 'restriction' because of the missions the B-17s were assigned. The maximum internal bombload was 9,600 pounds, and using the rarely-mounted under-wing bomb racks, each of which could carry a 4,000-lb bomb, it could carry up to 17,600 pounds of bombs; however, even with just the maximum internal bombload, maneuvers were restricted and fuel expenditure increased significantly, and the extra drag from the external ordnance limited the 17's range to the point where it had a range that would limit it to missions that the B-26 squadrons were already performing, so there was never any significant use of the B-17's full capacity.

[RTHolmes]

Damage photos can be misleading.  I could quite incorrectly deduce that the B-17 had a weak wing from photos like this: -

http://farm4.static.flickr.com/3100/2866596245_2e7f6c0470.jpg

photos like that put our AH war into perspective - give me goosebumps

[EDO43]

You ever been in a Lancaster?  The climb over the main wing spar to the cockpit from the wireless op position is really something.  I have no idea what is stronger between a Lanc and B-17.  I do know that Alex Henshaw barrel rolled a Lancaster no problems though.

Damage photos can be misleading.  I could quite incorrectly deduce that the B-17 had a weak wing from photos like this: -

http://farm4.static.flickr.com/3100/2866596245_2e7f6c0470.jpg

(Image removed from quote.)

The photo posted is of "Wee Willie", 91st BG, 322nd BS, Coded LG*W, serialed 42-231333.  This is the second photograph in a three shot group taken by the strike camera of another fortress, the last showing her exploding at around 6,000 ft.  Eye witnesses in the surrounding aircraft say she took a direct hit from flak in the L/H wingroot over Stendahl on April 8, 1945.  Reports that allude to an Me262 attacking her and tearing her wing off are false yet appear in more than one text I've examined.  There were no 262's in the vicinity that day from what the 91st combat reports indicate.  It doesn't matter how tough your wing is, a direct hit in that area by 88mm or 120mm flak and it's over.

[B-17]

Wee Willie is popping up EVERYWHERE to me right now...

[colmbo]

Not just photos of damage. The general structure under the wings. The framework is denser, thicker, heavier. The B-17 actually has a corugated layer of metal just under the skin. the skin itself was rather fragile and a slip of a screwdriver could puncture it. It was the underlying corugated sheets and the frame that gave it the resilience which its reputation denotes.

Like I said, those examples and more. I'm not dissing the Lancaster. I just think the B-17s wing is clearly "stronger" -- that doesn't mean faster, more manuverable, etc. Just structurally stronger.

Superman might puncture the wing skin if his screwdriver slipped, but mortal human probably wouldn't do so.   

B-17 wing is quite stout.  The spars are a series of trusses.  Each rib is a truss assembly.  Then as Krusty pointed out there is a corrugated layer spanwise which really stiffens the wing.  Stick your head up inside a B-17 wing and you'll think you're looking at the underside of a bridge!!

[Butcher]

Superman might puncture the wing skin if his screwdriver slipped, but mortal human probably wouldn't do so.   

B-17 wing is quite stout.  The spars are a series of trusses.  Each rib is a truss assembly.  Then as Krusty pointed out there is a corrugated layer spanwise which really stiffens the wing.  Stick your head up inside a B-17 wing and you'll think you're looking at the underside of a bridge!!

Are we comparing the Lancaster that flew at night vs a B-17 that flew during the day? Apples to Oranges.  This entire argument is invalid from the beginning without the proof of both bombers taking the same damage and witnesses to the event. In reality, Bomber Command had a few raids cut to pieces and had missions flown at night - while so the American's were flying day light raids - so both situations are entirely different over all.

[B-17]

  Want to try explaining the second line of that again, Butch?

[Scotty55OEFVet]

It would not be much of a stukalanc if the wings went and ripped off.

 

[B-17]

It would, though... just not a very survivable one.

[Ashley Pomeroy]

The Lancaster was originally the twin engined Manchester and its wing was enlarged from the Manchester's when it was converted to be the four engined Lancaster.

Old topic, but I've been reading SAM Publications' fascinatingly detailed book on the Lancaster, which has a short chapter on the Manchester. Quoting from page seven, "the design was also to be capable of dive bombing (at an angle of 60 deg to conceal the type and also to offer better accuracy of ordnance delivery), torpedo dropping (this led to the very long bomb bay as the torpedoes of the time were 18ft 3in long), troop carrying and supply dropping!". The fashion at the time in both Britain and France was for multi-role aircraft, the idea being that this would save money by consolidating the same roles into fewer aircraft types. The French went for smaller designs, such as the Potez 540 and the Bloch MB 130 and so forth, we had the Manchester and the Blenheim. I surmise that the requirement for a long bomb bay would have forced the designers to make the fuselage extra-specially rigid, in the same way that convertible cars need scuttle reinforcement. This in turn would have increased the weight, which is one of the factors that doomed the Manchester.

Quoting further, "the long range of heavy bomb load of the type was to be achieved by the use of a catapult take-off". What appears to have happened is that all of these requirements were included in the original design, but dropped as requirements just before production finally started (the dive bombing requirement persisted until August 1938), so presumably they were engineered in but never used. The book describes a catapult launch of one of the Manchester prototypes. The MkIII Manchester had lengthened wings, presumably built to the same standard as the Manchester's original set, although ultimately the MkIII became the Lancaster.

All of this probably explains why the Lancaster was such a piece of work. Interesting to compare it with the Ju 88, which had a similar range of roles but was much smaller; I wonder if the Germans ever thought of putting four engines onto the thing? Probably would have made no sense unless the bomb bay was enlarged, at which point it's becoming a completely new aeroplane, and if you're going to build a new aeroplane, why not start from scratch and make the best! With the war as good as won there's no rush.