Fairly simple.
The way I remember it it´s just to look into "Options" then "Controls", you pick the plane and under the controls you´ll find "Start Left/Right Engine" and "Stop Left/Right Engine"
In the "Doc" folder of the main game´s folder you´ll find the manual too.
Give it a squeeze, it´s good stuff.
Hope this helps.
_________________________
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Para_Bellum
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Ice
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MigBuster
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