The minimum high power launch field is 162 acres, or 7,068,583 square feet. The cross-section of the average rocketman is about 3 square feet. If it rained rockets, the probability of getting hit by a falling rocket is about 2,356,194 to 1. If the event has 250 participants and spectators randomly walking around, the chance of some getting hit by a falling rocket is 9425 to 1. If 100 rockets were rained in, the probability of some one getting hit is approximately 94 to 1. Certainly more probable than 1 in a million.
The good news is that with a proper range safety practice in place, rockets don't randomly fall from the sky. Good range safety practice establish ballistic impact zones by angling the launch rails and rods away from the spectator areas so the 2 areas do not overlap by a large margin. Under this condition, the probability of some one getting hit from a falling rocket is vanishingly small, unless some one is out in the ballistic recovery area recovering a rocket.
There are many mechanisms that defeat good range safety practices.
3. Failure of the sponsoring organization to analyze the field layout and and the wind and proactively prevent launches towards or over the spectator area by instructing the launch crew and the owners on range rules and enforcing them.
2. Failure of the launch management personnel to monitor the rod angle and wind direction to proactively prevent launchs towards or over the spectator area.
1. Failure of the rocket owner to set and check the launch angle and the wind to proactively insure his rocket will not launch towards or over the spectator area.
Rockets don't simply fall from the sky. Someone assembled the rocket and put it on the pad, and adjusted the rod angle that determined the ballistic trajectory of the rocket. That person is directly responsible for the accident. If he had set up his rocket properly, the accident would not have happened.
The LCO and the launch crew also share responsiblity for the accident. They launched the rocket and did not adequately check to see that the ballistic rocket trajectory would not impact in the spectator area.
The launch organizers also share responsibility in failing to adequately train the launch crew and to instruct the rocket owners to properly angle the launch rods away from the spectator area.
Good PA systems and heads up alarms are fine, but should not be used as an excuse to permit unsafe launch practices.
Wake up folks. Stop making excuses for being sloppy. Launch safety is no accident.
Bob