Remember the advert where the ladder slips and the guy kisses the floor at about 100mph.
Well,it happened to me......my own fault...was replacing a tile on the roof,and I put the ladders on the decking,so no grip whatsoever(I know,I know).
Gets about 10 foot short of the roof and they went.
Instinct told me to grab onto summat and I wrapped my arms round the aluminium ladders.
Was looking down and I actually said to myself..."this is gonna fuckin hurt"......anyway,hit the deck and fuck me.......snapped both my arms,dislocated my left leg,cracked a wrist,broke 4 ribs and a couple of toes......couldn't move obviously and it was about 10am so everyone was at work.
Had to lie there for about 4 hours till the window cleaner found me.
Won't do that again in a hurry.