It might be better to include a parachute above the rotors.
The Cirrus SR22 single engine aircraft has this (their system's called CAPS.) It lets you sail to the ground in the event of some catastrophic failure preventing you from landing the aircraft safely.
http://en.wikipedia.org/wiki/Cirrus_SR22
The Cirrus SR22 single engine aircraft has this (their system's called CAPS.) It lets you sail to the ground in the event of some catastrophic failure preventing you from landing the aircraft safely. http://en.wikipedia.org/wiki/Cirrus_SR22