Also wouldn't advise Tasers or stun guns on an aircraft.  I am a sheriffs deputy here in the states and Ive seen too many people fight through a hit with a taser. I myself have been hit with a stun gun and while I can say that it was very unpleasant (understatement of the decade) I wouldn't call it debilitating.  With the modern advances in frangible ammunition I wouldn't be particularly concerned with discharging a firearm on board an airliner.

Btw: There are both plastic and nylon type of quick cuffs.
we use them quite a bit in situations with large numbers of suspects.