Slitherine

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and it will outperform any 1 engine plane in combat - because it will survive better and it has punch.

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ORIGINAL: ChezDaJez

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and it will outperform any 1 engine plane in combat - because it will survive better and it has punch.

Susvivability as compared to a single-engine US aircraft should be a wash. True, 2 engines allow significant redundancy in combat however the tail section was much weaker than on a comparable single-engine aircraft. It was very prone to failure after sustaining even relatively light damage, especially if that damage was not evenly distributed along the booms or horizontal stabilizer.

Chez

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ORIGINAL: el cid again

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ORIGINAL: ChezDaJez

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and it will outperform any 1 engine plane in combat - because it will survive better and it has punch.

Susvivability as compared to a single-engine US aircraft should be a wash. True, 2 engines allow significant redundancy in combat however the tail section was much weaker than on a comparable single-engine aircraft. It was very prone to failure after sustaining even relatively light damage, especially if that damage was not evenly distributed along the booms or horizontal stabilizer.

Chez

Doesen't matter. In RHS an extra engine counts. So does armor and all metal construction. P-38 has all three.
So it gets the rating for them. The extra engine point matters for lots of reasons - 1 E planes are less likely to return even on non-combat missions. So it is properly a durability contributer.

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ORIGINAL: el cid again

Nope - no bonus in maneuverability for any plane. But there is a special bonus for a Russian bomber and a British bomber in durability. The Russian one has a cast armor forebody. The British one has geodesic construction.

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If it was your mod - how would you do it?

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ORIGINAL: Nemo121

Well British and German wartime accounts do point to the geodesic construction as being particularly strong and giving the British bomber involved a greater ability to survive damage inflicted.

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ORIGINAL: Nemo121

Scholl,

The argument you make proves nothing.

Firstly, not all of those bombers shot down had a geodesic structure.

Secondly, it is possible to argue that bombers which returned to base in a damaged condition would have been destroyed if they had not had a geodesic design. Conversely one can make the statement that more would have been shot down if they were not of geodesic design. Unprovable? Yes, in the same way as your assetion plays hard and loose with the facts.

Thirdly, I've seen several RAF debriefings in which squadron commanders etc wax lyrical about the amount of damage the bombers with a geodesic design could take and still return to base when compared to their previous bombers. So that's evidence in the record.

Fourthly, structural design textbooks clearly state that geodesic designs are stronger than spheroidal or tubular ( constant diameter tube with rounded ends... typical for most WW2 airplanes) designs. When physics and structural analysis supports it being stronger I'll believe them.

Facts make something so. Saying it is so proves nothing.


So, we have historical reports from debriefs, we have backup from physics departments around the world and we have the reality that the 94 losses over Nuremberg don't actually prove anything one way or the other. Even if, for the sake of argument, those 94 bombers had all had a geodesic design all that might mean is that non-geodesic bombers might have lost 120 bombers over Nuremberg that night.  I think it is fairly obviou that geodesic designs DID convey a durability benefit. How much is something up for discussion.

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It's only "stronger" if the same weight of material is put into the airframe

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ORIGINAL: Nemo121

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It's only "stronger" if the same weight of material is put into the airframe

Well, another way of putting that is to say that per unit weight a geodesic airframe is stronger than a non-geodesic airframe, particularly a long non-geodesic one ( such as many bombers of the time had). Sounds like a perfect case for putting an adjustment in for a geodesic airframe.

After all it lookes like durability takes into account the weight of the plane. So, if that is so then it stands to reason it should take account of non-weight structural factors also... geodesic structure is one of these factors and, therefore, should be taken into account.

You've admitted that per unit weight a geodesic frame is stronger ( more durable) so under what grounds would you now exclude something from consideration which, by your own admission, acts to make an airframe more durable?

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ORIGINAL: Nemo121

... I think you aren't open to seeing my contention.

...

I know you have issues with accepting other's views ...

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ORIGINAL: witpqs

So (in that case) you took advantage of the stronger design to
a) save material
b) carry more weight

You gave up the chance to build a stronger airplane, instead opting for a and b (above).

Right?

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ORIGINAL: Mike Scholl

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ORIGINAL: el cid again

Nope - no bonus in maneuverability for any plane. But there is a special bonus for a Russian bomber and a British bomber in durability. The Russian one has a cast armor forebody. The British one has geodesic construction.

The Sturmovik certainly deserves a "special" consideration..., even the Germans called it a flying tank. But I don't thing the Brits should get an "edge" for the Wellington/Lancaster/whatever. The geodesic construction was stronger, but the Brits used it to lighten the overall aircraft and increase bombload (show me another bomber that can carry an 11-ton "Grand Slam" bomb)......When the Germans could find them in the dark, British bombers went down at a depressing rate.

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ORIGINAL: ChezDaJez

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If it was your mod - how would you do it?

I would take into account where ever possible any particularly vulnerable part of an aircraft such as the tail boom on the P-38 or radiators on inline-engined aircraft. I would probably use a + / - system to rate them. Add for self-sealing fuel tanks, armor, and structural integrity. Minus for in-line engine or structural weakness such as the dive limitation for the Zero.

From what I've read, I don't think your mod is that far off from what I might have done. I just might have carried it a bit further if possible. We can quibble over things here and there but I do like the fact that you have taken into account wing-loading for maneuverability.

Chez

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ORIGINAL: witpqs

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ORIGINAL: Nemo121

... I think you aren't open to seeing my contention.

...

I know you have issues with accepting other's views ...

Actually, this is the first time I've seen you explain clearly what you mean. I doubt it's a lack of openess.

I know you're speaking to Mike, but I thought a 3rd party viewpoint might be helpful.

What you are saying makes some sense. There is still one question - even though the geodesic shape is pound-for-pound stronger, does it actually resist damage in proportion to its additional strength? Explaining what I mean, a classic arch is very strong, but if the keystone goes the whole thing falls in a heap. Does the geodesic shape of the aircraft have the same vulnerability in that due to the continuous shape of the structure all of the pieces are, in effect, 'keystones'?

BTW, I am asking because I don't know, I am not arguing one way or the other.

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ORIGINAL: Herrbear

Something I just thought of concerning the dividing by the number of engines. Now that Wing Loading and Power Loading is taken into account do you penalize multi engine planes for speed and ROC. Wouldn't all planes, in theory, be consistent for those two factors. For example, shouldn't a 2-engine plane with 1000 hp engines with a ROC of 3000 and weight of 10,000 lbs work the same as a 1-engine plane with a 2000 hp engine also with a ROC of 3000 and a weight of 10,000 lbs.

Why would the 2-engine plane be penalized in those factors?

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ORIGINAL: witpqs

Except for the case of multiple engines along the center axis (very rare), multi-engine planes in WWII have their engines on/in the wings. Because the engines are heavy, this means that they have a lot more inertia to overcome when they try to roll. It's basically the physics concept of angular momentum.

This is one big difference between single and multi-engine planes in WWII.

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ORIGINAL: el cid again

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ORIGINAL: Herrbear

Something I just thought of concerning the dividing by the number of engines. Now that Wing Loading and Power Loading is taken into account do you penalize multi engine planes for speed and ROC. Wouldn't all planes, in theory, be consistent for those two factors. For example, shouldn't a 2-engine plane with 1000 hp engines with a ROC of 3000 and weight of 10,000 lbs work the same as a 1-engine plane with a 2000 hp engine also with a ROC of 3000 and a weight of 10,000 lbs.

Why would the 2-engine plane be penalized in those factors?

The multi engine penalty - it is not just for twin engine planes - but all of them - is meant to address the problem of conservation of angular momentum. It is meant to say that it is a severe restriction on maneuverability. It is a nice part of the function - whatever the number of engines - it goes there. There is, however, this caviet: multiple engines on one axis count as one engine. This can occur in 3 ways (and does NOT occur in WITP so far).

1) Two engines coupled to act as one.
2) Two engines with a common shaft - driving counter rotating screws on the same hub.
3) Two engines on a single axis - one driving a tractor and one a pusher.

Anyway - the number of engines is in the deonominator because that is the right place for it to be. It divides what otherwise would be the maneuverability value - a composite function - by N. It is not meant to say any particular element of that function is so divided.