Episode 155: Inverted Underwater Car

Air Date: November 24, 2010

It is more difficult to escape from a sinking car that flips upside down than from one that remains right-side up.


Jamie first built a device to spin a person underwater in an attempt to induce disorientation. Though Adam was consistently able to swim to the surface, Jamie had some trouble doing so himself.

Next Adam and Jamie arranged a full-scale test at a man-made lake, placing a car on a barge and making it flip upside-down when pulled into the water. Adam sat in the driver’s seat with emergency air tanks and a safety diver also inside the car. His goal was to escape without breaking a window and without using the air supply. As soon as the car hit the water the windshield cracked and began to leak water. Adam could not open the door until the car completely filled with water, equalizing the pressure on both sides of the door. The car did two half-flips while sinking and Adam became somewhat disoriented. He eventually surfaced, but admitted that he had to use the air supply, so he and Jamie declared the myth confirmed.

(The MythBusters previously tested underwater car escape scenarios in Underwater Car.)

In a room filled with flammable gas, firing a pistol through a full carton of milk will prevent its muzzle flash from igniting the gas.


The Build Team constructed a full-scale test kitchen, with typical fixtures and appliances as well as a breakaway wall to relieve the pressure from any explosions. Setting up Buster and a dummy to duplicate the film scene, they pumped in enough methane (representing natural gas) to achieve a 10% concentration, the center of the gas’s flammability range in air. Firing a 9 mm SIG Sauer pistol failed to produce an explosion, whether or not a carton of milk was placed in front of it.

The team then built a bulletproof glass box to serve as a small-scale kitchen, pumped in the methane, and tested three different weapons – the SIG Sauer, a 9 mm Glock pistol loaded with +P rounds, and a .44 Magnum revolver. None of these caused the methane to explode when fired, so the team switched to more flammable hydrogen gas. Without the milk, the Glock gave an explosion where the SIG Sauer did not, so they built a dollhouse-sized kitchen for mid-scale testing with the milk in place. This test ended in a blast that blew out the walls and roof, leading the team to classify both the movie myth and its underlying concept as busted.

(This myth was inspired by a scene from the film Kiss the Girls.)


  1. craig says:

    concerning using a pair of jeans to zip-line down a ski lift cable have you considered doing it in the winter during iced conditions?

    • Pithecanthropus says:

      The cables would not ice up as they are in constant use.

  2. kirk says:

    why was the gun not in the gas on the small scale….the air/gas mix not around the gun and not inside the gun and barrel???

  3. Brooksie says:

    The movie never said the gun would set off the gas. The “bad guy” simply assumed it would. Really the myth is confirmed since shooting through the milk would not set off an explosion. Since the movie never showed that the explosion would occur without the milk, the team tested the assumption, not the actual action.

  4. Ben Luberti says:

    How about an car with an sliding door? Shall the outcome be the same?

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