Well, don't worry about your framerate in the tower too much, as it will tend to be lower due to all the objects at a large airfield. However, that is very low, and is going to be a problem.
What speed K62 do you have? The K6-2 is a problem in Aces High, since AH relies on Floating Point math a great deal, and the weak point of the K6-2 is it's Floating Point math Unit (FPU). Just about any other processor will have an easier time with Aces High... even a slower Celeron will do better than the K6.
Your system RAM and Video card are fine, your CPU is the bottleneck here. Until you upgrade that piece, there isn't really anythning that can be done to get your framerates up to a playable level.
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Lephturn - Chief Trainer
A member of The Flying Pigs
http://www.flyingpigs.com "A pig is a jolly companion, Boar, sow, barrow, or gilt --
A pig is a pal, who'll boost your morale, Though mountains may topple and tilt.
When they've blackballed, bamboozled, and burned you, When they've turned on you, Tory and Whig,
Though you may be thrown over by Tabby and Rover, You'll never go wrong with a pig, a pig,
You'll never go wrong with a pig!" -- Thomas Pynchon, "Gravity's Rainbow"
