Hello, bergkamp.
Taking off from carriers is one of the things I love from IL2. It is quite challenging, and especially with F9F Panthers. I don't know if flight model is historically accurate, but I've found that taking off with F9Fs is really difficult.
However, after seeing your posts, I've made some trials.
I made a simple mission in a Korea map, using the USS Essex CV9 1957 as home base (I suppose this is the Essex angle deck you have mentioned).
Player plane is a F9F-2 Panther 1949. It is loaded with 2x500 lbs bombs and 6x250 lbs bombs (I reckon it is one of the heaviest loads possible). I have just BATEP07, no BATCATS installed yet.
I didn't manage to take off with 100% fuel load.
However, I was able to take of with 50% fuel load.
On deck, attached to catapult. Flaps on landing set, wings unfolded, elevator trim at maximum.
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Throttle at 100%, wait and listen to the engine until it stops changing pitch, release chocks.
I pull joystick back almost at maximum:
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Gear up as soon as you leave the deck. Flaps quickly in normal setting. Still pulling back the joystick:
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Oops! Almost touching water! Cannot pull back further!!! Houston, we've got a problem!
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Hey, take it easy. Situation going back to normal.
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Pheew! Mission accomplished.
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I admit it is a difficult task, but it is possible. However, it is fully rewarding once you managed it.
Good luck!