(De-lurking)...
Well, you have to decide what aspects of the airplanes and combat you're trying to "replicate." The fuel multiplier, IMO, is there more or less just to make drop tanks "work" and provide a reason for their existence, as an added realism feature (a jaded observer might say that it's just to add another feature that other sim doesn't have, just as collisions were added in WB to enable headon attacks that AW didn't have. But I'll opt for saying that it's another good step in the direction of added realism)
At any rate, what are the objectives?
--Give "long-range" planes an endurance advantage over "short-range" planes.
--Make certain parts of the map accessible only to certain planes.
--Limit "interceptors" to their real-life mission.
--Force players to manage their fuel supply.
--Force players to load "full tanks" for sorties.
--All of the above?
Some of those work, some don't. The fuel multiplier limits your "minutes aloft," but unfortunately it doesn't permit you to climb to realistic altitudes if your plane has a small tank, while allowing drop-tank planes to get a "virtual airstart" by expending their "excess" fuel to climb. Planes with large capacities can, likewise, load small "dogfight loads" and get a weight advantage over their fully-laden adversaries.
Overall, I think fuel management is "good," but realistically, you're not going to have to "worry" about your fuel every 3 minutes on a 30-minute flight. You'd ALWAYS have "enough" fuel to get to your combat area, strike the target, fight, and egress. You'd "worry" at the midway point and on the way home, and you'd "manage" as necessary. In an AH sortie, much of your time is spent fuel-managing, probably too much.
What if, instead of scaling the fuel multiplier, you did some of this with the ENGINE modeling instead? Once you accept a "suspension of reality" on how long your fuel really lasts (and a Corsair's fuel DID last 5 times longer than a 109s, that's "reality," but when that means an AH Hog can fly for 90 minutes and a 109 for only 18, that's silly) then does it really matter which "performance factor" you're fiddling with.
Suppose you got rid of the fuel multiplier, and then engine fuel consumption were tweaked so that you burned a lot of fuel for climb and combat and VERY little for "cruise"--IF you managed your engine and fuel correctly (and the controls already exist to do both). Interceptor-types would then have SOME capability to "hunt," but only if they play their hunting altitude against their cruise range. Scale it with, say, the 109 or Spitfire as a "baseline," and give that plane a "target duration" of, say, 45 minutes, with enough fuel to climb to 20K, fight at full power for 5 minutes, descend and land at idle power, and fly at "cruise power" for the remaining time. Scale the rest of the PLANES, not the terrain or fuel loads, so that if a plane had an endurance of 5 times what the real Spitfire had, it would have 5 times what the AH Spit has, under the same climb to 20K, fight 5 min, cruise the rest of the time conditions.
Note that I'm not talking about engine OUTPUT here, that stays "real." But engine fuel consumption would vary from plane to plane. You're talking about duration of flight here. As long as some "realistic" fuel management takes place, that should be "good enough," without making that the whole focus of your flight.
------------------
