Mitigating the risks from small UAVs

Earlier this week, the FAA released proposed rules for operators of small UAVs (drones).  Small UAVs are those that weigh less than 55 pounds. 

From a risk management perspective, the rules propose a variety of preventive actions: fly only in daylight, do not fly over people, do not fly in bad weather, fly below 500 feet altitude, fly at speeds less than 100 miles per hour, and do not fly in airport flight paths and restricted airspace areas.  Most of the rules are meant to prevent accidents by reducing the likelihood of losing control, colliding with other aircraft, and crashing into third persons on the ground. 

The rules do not propose any contingency plans to minimize risk when the operator loses control of the UAV.  Indeed, perhaps the only ones that can be considered are fanciful ones like a "disassemble" command that makes the UAV divide into smaller pieces that would cause less damage on impact or deploying airbags like those on the Mars Pathfinder.  A more reasonable contingency might be a siren and flashing light that are activated to warn those nearby when the UAV begins to crash (like shouting "fore" when a golfer drives a ball towards unsuspecting bystanders).