AADs (Automatic activation devices)
An AAD is a much needed safety device in skydiving. The AADs function is that of a automatic parachute deployment device. In other words AADs serve to open the parachute at a curtain altitude or after a curtain amount of time has passed. AADs are typically used to open the reserve parachute container at a preset altitude if the descent rate exceeds a preset activation speed. This indicates that the user has not opened his or her parachute, or that the parachute is malfunctioning and is not slowing the descent rate sufficiently.