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Old 09-26-2009, 11:12 PM
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Voyager Voyager is offline
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Quote:
Originally Posted by Daiichidoku View Post
i thought that trading 3 control axies for PK was quite teh funneh
[...]

the really funny thing was, i found, that 2 patches later, the exact same thing could happen to (at least) all the other US types, F4Us, P47, P51, P38

in any event, it is what it is, i dont see why any type with seal-sealing tanks could not suffer catastrophic failure and lose all fuel in short order IRL...its annoying, but live with it, and set your glide hdg towards home



about TD looking into CoG issues with P51 (or any other type for that matter), AFAIK, il2 does not model separate fuel tanks in P51, hence there is no real problem in that regards?
On the fuel drain debate, I believe the argument is that planes with multiple discrete fuel tanks a catastrophic hit in one tank would most likely drain just that tank, rather than the entire fuel system, but with the basic limitations of the Il-2 engine, a catastrophic hit in one tank would behave as a catastrophic hit in all fuel tanks. This is true for all aircraft in the game; it shows up most often on the US aircraft, because the USAAF and USN fighters have 3-4 times the max fuel of other comparable aircraft.

The "burning planes" was the same sort of thing. When someone sprung a leak, you could light it off by firing tracers through the leak cloud, and it would burn until the plane exploded, or the fuel ran out. People just noticed more often on the 190 and P-47, because those two took a whole lot more damage to bring down than other planes, but I found you could do the same thing to 109's, and pretty much anything else that took more than two burps of 0.50 cal. Was great fun until they fixed it.

The issue with the P-51 CoG is that as I understand it, Il-2 models the plane's fuel tank system as a single larger fuel tank placed at the aggregate CoG of the entire system, and as a consequence, all tanks are treated, in effect as though they were being drained equally. On most planes that is fine, because the fuel system as a whole is balanced around the aircraft's Center of Gravity. The P-51's is not. The Mustang has two 540lb (245kg) fuel tanks placed in the wing spars, placed very close the to CoG, and in the P-51B-10, they added a 3rd 510lb (230kg) fuel tank behind the pilot, about 3-4 feet behind the CoG. Picture, if you will, a P-51 with a 500lb bomb hung off of the radiator.

The upshot of this is, during flight, the center of mass of the P-51's fuel system move forward several feet during the first third of the flight, and then for the next 1,200 miles, just wobbles right a left a bit, as the pilot juggles the wing tanks to keep some semblance of roll balance.

Actually, after reading through all of what I just wrote, I just realized, a balanced fuel system isn't going to induce large CoG shifts as it drains. Does Il-2 even have the capacity to model CoG shifts as the fuel system empties?

Harry Voyager

Addendum: If you guys are able to produce a solution for the P-51 CoG, could you flow it over to the BoP dev team? At the moment, the P-51D is about the only USAAF fighter they've got right now, it could really use that balance fix.

Last edited by Voyager; 09-26-2009 at 11:15 PM.