It should be...I would think all you need is the animation and a hot key. Also, they physics of the craft in both modes. Example of this... The Flak guns in Forgotten Hope.
The X-wing had folding S-foils in bf2, although I never got my hands on it so i can't really say how they workd. However vehicle skeletons in BF2142 alow us to give vehicles what ever animations we want. As for changing the abilities of craft when the S-foils change position, it may be difficult to do much more than speed the craft up.
So you mean that it is possible to lower and raise S-Foils in-flight? Would be very nice to see in-game. But is it possible to disable the X-Wing's weapons as long as the S-Foils are raised? Would be very nice to have travle (without weapon usage so that the higher speed does not result in an imbalance of the craft) and combat (with weapon usage etc.) speed.
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I think it could be implemented as an automatic feature purely for aesthetic reasons. Point of Existence managed this with the wings on their Panavia Tornado at any rate. I've never been too clear on what the S-Foils actually do, although I thought when locked in attack position they afforded greater maneuverability. But perhaps not.
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