Latest MythBusters Results

If a pressure-triggered bomb is cooled with liquid nitrogen, its detonation will be delayed long enough for a person to dive into a bathtub and cover himself with a bomb blanket, surviving the explosion. (Based on a scene in the film Lethal Weapon 2.)

confirmed

Adam and Jamie decided to test three facets of the myth: time to get off the toilet and into the tub, effectiveness of the liquid nitrogen in delaying the trigger, and ability of the blanket and tub to shield its occupants. After building a replica of the movie bathroom and incorporating all details of the scene, including a prolonged time spent sitting on the toilet, Adam was able to pull Jamie into the tub and under the blanket in 1.95 seconds.

On the bomb range, they set up a charge of C-4 and a high-speed camera to measure the delay between triggering and detonation. A control run with an ambient-temperature bomb gave a delay of 3.3 milliseconds, while pouring the liquid nitrogen directly onto the charge increased it to 15 milliseconds. When the liquid nitrogen was poured over both the charge and the battery powering the trigger, the bomb would not detonate at all until the entire rig had warmed up to ambient temperature, 15 minutes later. Adam and Jamie commented that the technique was actually more effective in real life than in the film; the characters could have simply stood up and walked out of the bathroom.

To test the third part of the myth, they built a bathroom set with a heavy cast-iron tub as seen in the film, put Buster in the tub under a blanket, and fitted the tub with sensors to measure the pressure inside and outside. When a 1 kg charge of C-4 was set off under the toilet, the entire set was destroyed except for the tub. The peak pressure outside the tub was a lethal 180 psi (1.2 MPa), while the inside sensor recorded 8 psi (55 kPa), meaning that a person would survive but have some chance of suffering hearing damage. Adam and Jamie declared the myth confirmed.

Airplanes can save fuel and money by flying in V-formation, similar to a flock of birds.

confirmed

While visiting a bird sanctuary, Kari and Tory learned the reason for the birds’ V-formation: air vortices from the leading birds’ wings allow the trailing ones to flap less often and less vigorously. Kari then built some model airplanes, which she and Grant took for testing in a NASA water chamber. With three planes in a V, they saw vortices at the lead plane’s wingtips that persisted for a large distance behind it.

At Tracy Municipal Airport, the Build Team met with a 9-member acrobatic flight club to test out different flying formation: V, wingtip to wingtip, single file, and a control run with no formation. A tight V reduced fuel consumption by 3-5% compared to the control, while the other two formations either gave no reduction or increased the fuel usage. The team declared the myth confirmed at this point, but noted that the close formation could pose a danger to the pilots. A second run, with the planes spaced farther apart, gave a fuel savings for only Tory due to the difficulty of staying in the lead planes’ vortices. Nevertheless, the team commented that even a small fuel savings could lead to a sizable financial advantage at a large scale.

When presented with the Monty Hall Problem, people tend to stick with their first choice.

confirmed

After they built a game show mock-up set at a local theater, Adam acted as a game-show host and had 20 volunteers play a game of “Pick a Door”. Once a player chose a door, Jamie opened an empty one and Adam offered the player a chance to switch; all 20 stayed with their original pick, many of them believing that they had a 50-50 chance to win at this point.

When presented with the Monty Hall Problem, people would be more likely to win if they changed their decision.

confirmed

They built a small-scale simulator to do 50 trials each, with Adam always switching his choice and Jamie never switching. Adam won far more often than Jamie did, and Jamie explained the reason: because the player has a 2/3 probability of choosing a losing door at first, switching turns the odds in his favor.

If a live grenade lands near a person, he can avoid shrapnel injuries by lying flat on the ground.

busted

The Build Team set up a grenade and placed rupture discs at 1 ft (0.3 m) intervals around it, from 1 ft (0.3 m) to 10 ft (3.0 m), in order to find the lethal radius of the blast wave. All discs at 5 ft (1.5 m) and closer burst, so the team set up plywood panels and a plastic roof just beyond this distance to gauge the shrapnel spread. Tests with both a mid-20th century “pineapple” grenade and a modern “baseball” device showed injuries at all heights from ground to roof level. Although the team judged the myth as busted, they found relatively few hits in the area corresponding to a person lying on the ground, indicating that lying down might reduce the chance of shrapnel injuries.

Some firing stances often used in movies allow a handgun user to shoot faster and more accurately than the standard two-handed stance.

busted

Adam and Jamie decided to compare six stances: two-handed, one-handed at shoulder level, shooting from the hip, gun held sideways, and two stances with a gun in each hand. They set up targets at 15 ft (4.6 m) and each took a turn firing 8 rounds from a .45 caliber pistol (16 rounds for the two-gun trials), evaluating their performance on a combination of speed and accuracy. With the two-handed stance as a benchmark, they discovered that none of the other stances yielded an improvement; only the one-handed, shoulder-level stance gave comparable results. Adam and Jamie cited the ability to look down the sights of the gun as the best indicator of accuracy in any firing stance.

It is possible to re-inflate a flat tire and re-seat it on its rim by spraying in engine starting fluid and igniting it.

busted

Kari sprayed the fluid into a deflated car tire and ignited it, but the tire did not inflate or re-seat. In a second trial, Tory stepped on the tire to mix the air and fluid; when ignited, the tire quickly re-seated and inflated to the point of bursting. Upon cooling, though, the gases inside the tire contracted and formed a vacuum inside the tire, making it useless. The Build Team obtained the same result with a truck tire, prompting them to declare the myth busted. Tory noted that although the starting fluid can be used to re-seat the tire, a source of compressed air is needed to inflate it.

12. Wettest & Wildest

Myth: Waterslide Wipeout

This segment featured details on building the massive, steep launch ramp for this myth, and Adam’s experience sliding down it.

11. Water Bomb

Myths: Water Safe, Black Powder Shark

This segment featured two of the cast’s favorite myths involving submerged explosives.

10. Out in the Cold

Myth: Swimming in Syrup

This segment revealed the challenges of staying warm during the swimming time trials, filmed during winter in San Francisco.

9. Dive! Dive! Dive!

Myth: The Squeeze

Revealed the Build Team’s unsavory experience with the pork dummy Tory built to help test this myth.

8. MythBusters on Ice

Myth: Blue Ice

The Build Team reflected on their visit to a NASA low-temperature wind tunnel.

7. Under Pressure

Myths: Exploding Water Heater, Steam Powered Machine Gun

This segment discussed dealing with the energy and hazards of steam in myth testing.

6. Pool Cruelty

Myth: Bulletproof Water

Revealed the mayhem caused by firing high-powered weapons into a swimming pool.

5. Water Torture

Myth: Chinese Water Torture

Highlighted the unpleasant experiences of Adam and Kari during this round of testing (Adam urinating on himself, Kari enduring the torture until a paramedic stopped the test and removed her).

4. The Life Aquatic

Myth: Octopus Egg Pregnancy

Adam discovered that the texture of his skin was unusually pleasant to octopuses.

3. Boatmageddon

Myth: Bifurcated Boat

The Build Team faced repeated difficulties in setting up and performing their tests on land.

2. Hidden Depths

Myths: Eye Gouge, Fish Flap, Fatal Flashlight

Memorable shark myths, as chosen by each cast members.

1. Rock the Boat

Myth: Building a Pykrete Boat

The inspiration for building a speedboat out of newspaper-based “Super Pykrete” stemmed from the cast’s second trip to Alaska.