A FRIEND AND I WERE ATTEMPTING TO LAUNCH HIS JETSKI. I BACKED MY TRUCK DOWN THE BOAT RAMP AND MY FRIEND WAS ON THE JETSKI. MY FRIEND WAS HAVING TROUBLE GETTING THE JETSKI TO COME OFF THE TRAILER SO, I PUT THE TRUCK INTO PARK AND GOT OUT TO SHOVE THE JETSKI OFF. AS I GOT OUT I NOTICED THE TRUCK LUNGE AND START TO ROLL BACKWARDS. I ATTEMPTED TO REACH MY FOOT BACK IN TO HIT THE BRAKE. BY THIS TIME MY SHOES WERE WET AND BECAUSE OF THE POSITION OF MY BODY, MY FOOT SLIPPED OFF OF THE BRAKE PEDAL AND SMASHED THE GAS PEDAL WHICH CAUSED TRUCK TO TAKE OFF IN REVERSE. AS I WAS STILL HALFWAY IN AND OUT OF THE TRUCK THE DOOR DRUG ME DOWN THE BOAT RAMP AND UNDER THE WATER WITH THE TRUCK. LUCKILY I WAS ABLE TO GET FREE AND HAD NO SERIOUS INJURIES. THE TRUCK HOWEVER WAS FULLY SUBMERGED AND THE JETSKI TRAILER WAS BROKEN IN THE PROCESS. NOTE: THE ORIGINAL TRANSMISSION WAS CHANGED OUT UNDER A WARRANTY CLAIM AT AROUND 10,000 MILES BY THE DEALERSHIP. *TR