JATO Rocket Car: Myth or Reality?
The account of the JATO Rocket Car (Links to an external site.) is an early example of a viral anecdote from the 1990s. In this story, a man supposedly met his death in a spectacular manner after mounting a JATO unit (a rocket engine used to help heavy aircraft to take off) onto an ordinary automobile. Here is part of the story shared via email back then:
The Arizona Highway Patrol came upon a pile of smoldering metal embedded into the side of a cliff rising above the road at the apex of a curve. the [sic] wreckage resembled the site of an airplane crash, but it was a car. The type of car was unidentifiable at the scene. The lab finally figured out what it was and what had happened.
It seems that a guy had somehow gotten hold of a JATO unit (Jet Assisted Take Off – actually a solid fuel rocket) that is used to give heavy military transport planes an extra ‘push’ for taking off from short airfields. He had driven his Chevy Impala out into the desert and found a long, straight stretch of road. Then he attached the JATO unit to his car, jumped in, got up some speed, and fired off the JATO!
The facts as best could be determined, are that the operator of the 1967 Impala hit JATO ignition at a distance of approximately 3.0 miles from the crash site. This was established by the prominent scorched and melted asphalt at that location. The JATO, if operating properly, would have reached maximum thrust within five seconds, causing the Chevy to reach speeds well in excess of 350 MPH, continuing at full power for an additional 20–25 seconds. The driver, soon to be pilot, most likely would have experienced G-forces usually reserved for dog-fighting F-14 jocks under full afterburners, basically causing him to become insignificant for the remainder of the event. However, the automobile remained on the straight highway for about 2.5 miles (15–20 seconds) before the driver applied and completely melted the brakes, blowing the tires and leaving thick rubber marks on the road surface, then becoming airborne for an additional 1.4 miles and impacting the cliff face at a height of 125 feet, leaving a blackened crater 3 feet deep in the rock.
Use concepts of momentum and impulse, you are going to determine the plausibility of this story. You are to ignore other non-physics reasons to question whether or not someone could successfully attach such a rocket to an old sedan. Instead, you will focus your analysis on whether or not the speeds claimed in the story were possible.
Review the useful information provided below prior to beginning your assignment.
Rocket Motor, Solid Fuel, 15-KS-1000, JATO (Links to an external site.)
The motor produced 1,000 pounds of thrust for 15 seconds.
Loaded Weight: 143 lbs
1967 Chevrolet Impala
Shipping weight = 3500 lb