Execute the Reverse Brake Slam

What happens here

With the tailgate of the Ford pickup truck lowered, the presenter enters the driver's seat. He proceeds to drive the truck backward at a high rate of speed down a gravel driveway. At a specific moment, he abruptly slams on the brakes. The sudden deceleration, combined with the momentum, causes the John Deere riding lawnmower to launch out of the truck bed, clearing the tailgate, and landing on the gravel and grass beside the driveway. The entire event is captured from multiple angles, including the truck's interior, the GoPro mounted on the mower, and the aerial drone.

Goal: Successfully eject the lawnmower from the truck bed as planned.