Make a file called takeoff.sqs and copy following in it:
_plane = _this
_startingdirection = direction _plane
_a=0
#takeoff
_a=_a+1
_plane setvelocity [(sin direction _plane)*2.5*_a,(cos direction _plane)*2.5*_a,0]
_plane setdir _startingdirection
~.125
? (_a<30) : goto "takeoff"
_plane setvelocity [(sin direction _plane)*2.5*_a,(cos direction _plane)*2.5*_a,_a/8]
_plane action ["Engine on"]
Then call it just like that:
myplane exec "takeoff.sqs"