Episode 70: Hindenburg Mystery and Crocodile Zig Zags
- The Hindenburg disaster caused by material painted on the skin, not the hydrogen inside: busted
- If you are getting chased by a crocodile, you can escape by running in a zig-zag pattern as crocs cannot turn corners: busted. Crocodiles are ambushers -- they probably won't chase you on land.
The Hindenburg myth is one of the best mythbustings they have done in awhile as it coupled a well-known historical debate with compelling results -- their footage looked very similar to the actual Hindenburg newsreels. It also added in the explosive element that the MythBusters are well-known for. They were able to give some credence to the paint theory as their experiment did show some thermite-like reactions occurring, but it was clear that the hydrogen as the main contributor to the disaster.
The crocodile myth was more of bust as there really wasn't much to test. After spending a lot of time building and calibrating a rig, they were reduced to dangling food in front of an alligator's mouth. This was really a test of whether or not crocodiles and alligators chase prey on land rather than any particular escape technique.
Myth: The Hindenburg disaster caused by material painted on the skin, not the hydrogen inside
Hindenburg Disaster: On May 6, 1937, the Hindenburg zeppelin came into land at Lakehurst Naval Air Station. The zeppelin fully went up in flames in less than a minute, killing 35 of the passengers.
Addison Baine, retired NASA scientist, claimed that the airship's metal paint was responsible for the flaming carnage, not the hydrogen.
The skin of the Hindenburg was made out of 100% cotton treated with a doping compound that included aluminum powder and iron oxide. Aluminum powder and iron oxide happen to be two ingredients in thermite. Adam prepared a 4500 degrees demonstration of thermite in a skillet
The skin of the Hindenburg wasn't treated equally -- the upper half and lower half had different coatings: * Upper half: base coat of butyrate and iron oxide with three coats of butyrate and aluminum on top * Lower half: base coat of butyrate with three coats of aluminum power on top
Only the upper half had the thermite-making compounds in combination. The coatings were chosen to reflect the heat and light from the inner bladders containing hydrogen.
They setup four square panels (about 1'x1') to test the flammability of the Hindenburg skin: * Raw fabric: 5:25 to burn (10 times longer than the entire Hindenburg) * Bottom composition: 2:26 to burn * Top composition: 5:30 to burn * Thermite: it didn't seem to burn at first, but it suddenly ignited (to the surprise of Adam) and was consumed in 20 seconds.
Their test of the three panels already put doubt to Baine's theory.
Eyewitness combined with film footage verified that the Hindenburg burned a bright orange. Adam set a column of hydrogen on fire, which showed that hydrogen does burn orange, but it was much less brilliant and harder to see than in the film footage.
Side fact: The Hindenburg was filled with hydrogen because of a US embargo on helium to Germany. Hydrogen also allowed for better lift.
Hydrogen + Skin flammability
Adam tried a small-scale test to get both hydrogen and the skin to burn simultaneously. He filled a small box with helium and stuck the skin on top. The box ended up exploding the skin off instead of burning.
1:50 scale tests
Their final test featured two 1:50 scale models of the Hindenburg: 1. Hindenburg skin, no hydrogen 2. Hindenburg skin, with hydrogen 3. 'Megadope' (lots 'o Thermite)
Jamie went to Western Steel & Wire Co to pick up appropriate size wire to build their scale models. Jamie managed to set one of the models (pre-doping) on fire after deciding to do some last minute welding.
Adam: "These things are always catching on fire"
As they weren't testing what caused the initial spark, they used a blowtorch to ignite each of the Hindenburg models. Multiple cameras, including a thermal camera, captured the burning.
- Hindenburg skin, no hydrogen: 2:06 to burn. The burning initially went very slowly with a couple of thermite-like sparks. The burning accelerated after about half of the rig was in flame. The test busted the myth, but it did give partial support to the myth: it showed that thermite-like reactions were possible even though the thermite components were suspended in different layers.
- Hindenburg skin, with hydrogen: 0:59 to burn. Their small scale test looked very similar to the Hindenburg newsreel.
- 'Megadope': they painted the model with 15 lbs of thermite. The scale model went up in a huge inferno in 0:30.
busted: the skin did show thermite-like reactions, but the hydrogen clearly played a role as the burn time was twice as fast.
Myth: If you are getting chased by a crocodile, you can escape by running in a zig-zag pattern as crocs cannot turn corners.
The build team constructed an elaborate zig-zag rig to try and test this myth. The rig featured a remote-control trolley on a steel track that could zig-zag and dangling dummy in front of a crocodile. They used a foam Buster instead of the real Buster in order to lighten the load. They also gave the foam buster legs made out of fishnet stockingsfilled with quail (a delicacy for crocodiles).
Human running speed
The build team need to calibrate their rig to actual human running. They setup a grid on the floor and filmed themselves running across it. The high-speed footage showed them zig-zagging at 7.6ft/s (5mph).
Real croc test
They took their rig all the way to St. Augustine Alligator Farm, the only place to have all 23 species of crocodile on hand. Tory helped wrangle and tape the mouth shut of a Cuban crocodile, one of the quickest and most aggressive varieties. The first Cuban crocodile wasn't tempted by the quail legs and neither was the second.
They switched from the zig-zag rig to Grant's BattleBot with quails attached. No luck enticing the crocs.
They then decided to put Tory on the line by having Tory entice and then flee a Johnstons crocodile.
Crocodiles are ambush predators and it was quickly becoming clear what that meant: they don't chase prey on land. It's most important to get away from their initial attack.
Real alligators test
They weren't having any luck to get the ambushy crocs to chase so they switched over to an alligator. Both Grant and Kari took their turns dangling quails in front of alligators. Kari did the best at getting an alligator to follow as she slowly zigged and zagged backwards. The zig-zagging didn't really matter because the alligator wasn't chasing quickly.
Troy: "I don't know if she's more afraid of the alligator or the bird"
Busted: crocs probably won't chase you on land, so it doesn't matter if you zig or zag.