Obviously one does the appropriate performance calculations before attempting a take off.
A long time ago I was told that, as an additional check, I should pick (and mark if necessary) a point X% along the runway. If I hadn't reached Y% of my expected flying speed by then I should abandon the takeoff. This would (should) always give me a safe distance to stop in - especially in taildraggers.
My problem is that I always seem to fly aircraft with a performance meaning that I know there is a problem if I am not airborne halfway down the runway. Combined with the fact I was given this gem "a long time ago" I cannot remember X and Y.
Can anyone give me any suggestions?
Thanks
OC619