Superpilot wrote,"Side-stepping slightly, how easy/difficult is it for a pilot to scrape the tail along the tarmac? incorrect Vr calculations? ...surely not. Pardon my ignorance but from the experience I've had in real jet sims, it's pretty difficult "
My experience hasn't gone larger than antique DC9-83's, so I can't speak to the 777; but in the MD80 you could get a tailstrike by having the trim setting a little off. Also, as you guessed, if you are off in our weight calculations, you could derive an incorrect rotation speed; which would lead to achieving the takeoff attitude before the aircraft was ready to fly. In this situation, you must maintain that attitude until the aircraft lifts off; if you attempt to yank it off, you will only drag the tail. . .My MD80 operating manual states: If rotation is abnormal and lift off does not occur at 6-8 degrees pitch, stop rotation at 10 degrees until lift off occurs to prevent tail strike>. .regards