Airborne artist beat me to it again although I thought it may have been nearer 3 to 3.5 but it depends as said on drop height, weather conditions, time of day and a s**t load of other things that can really screw your day up such as strength and capabilities of the enemy.
However I'll bow to superior knowledge - thanks AA.
Transall, excellent comment. I found that the airborne squaddie had a deal more professionalism about him than the 'standard issue grunt' and could be relied upon to go longer and futher without any substantial support.
As for German paras in WWII, they had more balls than me, those bu**ers dived out the aircraft head first - sod that for a laugh - feet first is bad enough. Their equipment was also significantly different to allied gear and not as reliable.