Length of drop required to cause death by dislocation rather than strangulation yet without causing outward bodily mutilation:
Body weight:    Length of drop:
15stones +         2ft 5"
14                     2ft 9"
13                     3ft 2"
12                     3ft 9"
11                     4ft 6"
10                     5ft 5"
9                       6ft 8"
8                       8ft 3"
7 stones or less 11ft 0"
Thus women, who are by nature less heavy, have a more frightened final moment, alas.
(Berry, J. My experiences as executioner, ISBN 0 7153 5430 2)