In 1947, a US military physician call John Paul Stapp strapped himself into a modified ejector seat and prepared for the ride of his life. The seat was mounted on a railed sled propelled by a rocket. Contraption and Stapp were accelerated to a breathtaking 632mph and then deliberately decelerated to zero in just 1.25 seconds. The demonstration was part of Project Deceleration, aimed at developing safer ejection seats and proving the value of seat belts.
Modern contenders for the water speed record believe that Campbell, and others who have perished in a similar manner, would have survived if they had the facility to detect when they were about to 'take-off' and the ability to compensate and prevent it from happening. These days, this should be possible with onboard computers and electronic controllers that adjust airfoils, reacting to changes faster than is humanly possible. This at least is what Russ Wicks will be hoping when he eventually attempts 400mph in his boat, American Challenge.
Stapps' deceleration produced a force of more than 40G, or 40 times the force of gravity, giving him a momentary body weight of more than 3000 kilograms. Because his entire body was firmly strapped to the seat he only suffered retinal haemorrhaging, a few cracked ribs and two broken wrists, one of which he reset himself whilst walking back to the laboratory after the ride.
