Then, something snapped, and he fell.

He remembered as he fell the look of horror on the up-raised faces of his friends, and then everything became a blank.
It all happened in a flash, much too quickly to do anything but stand and wait until the aeroplane had crashed to the ground, but it seemed much longer, and Anne remembered later that she had felt a curious impulse to run away and hide.

If David were to meet his death through this new toy, she could not endure to stay and see it happen.
But David was far from dead.

He was only stunned and dizzy from the swift descent.

He had not been high enough from the ground when the accident occurred to sustain serious injuries.