there are some problem on this plane may be the reason of it keep diving into water
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pitch and roll propulsion too low so it's hard to control(add some control surfaces or jet and adjust PID)
wander distance too short ,always turning so it's hard to maintain altitude
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other problem
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custom jet intake are blocked
jet at middle are not efficient for control pitch
too many fuel and ammo box ,replace some of them with material box
attack run can't finish because Abort attack run distance are 0 (set it a little higher)
don't need forward and strafe PID
don't need fuel engines ,electric engines ,battery and RTG for this plane (might change depend on how many more jet you add)
bombs are useless...because they are small
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Hope these can help you