An employee was attempting to land a pallet jack on an outrigger landing platform (Level 12). The employee was signaling the crane and controlling the load at the same time. His hand was in the open slot at the end of the forks where the wheel retracts into the fork. The wheels were not powered down, but extended because of gravity. As the load was brought down, the wheels retracted into the opening, pinching the employee's fingers. The index and middle fingers were severed at the first knuckle.