5 Things Hollywood Doesn't Understand About Gas Tanks
If Michael Bay and Sir Issac Newton switched places, our action movies would be a bit more dull, and our laws of physics would resemble something closer to “For every action, there is an astronomically huge reaction, most likely a fiery explosion.”
Fortunately, we don't live in that world. And while we respect the way Michael Bay choreographs action sequences and car stunts, for the most part he gets them wrong. And it's not just him—it's all of Hollywood. Here are 5 things Hollywood just doesn't get about gas tanks.
Turns out car explosions don't send sedans flying 25 feet through the air. That's either good if you've made a habit out of actively speeding through gunfire, or a little disappointing if you were hoping Hollywood physics were accurate.
In reality, not many things can cause a car to explode - and that includes gas tanks. A head-on collision will only result in crunching metal, and a bullet would likely only cause some internal damage. What you really have to worry about are:
- Batteries. A defective charging system or battery releases hydrogen, which could cause an explosion if sparked the right way.
- Fuel and oil leaks. If fuel or oil leaks onto something hot enough, it will explode. However, these cases are extremely rare and are most likely to happen in insurance fraud cases.
Gas Tank Leaks
Speaking of gas leaks, what happens in the clip below from The Fast and the Furious doesn't happen in real life. In fact, Penn and Teller found a dude with a big gun and tested out the movie theory to no explosions. It turns out that gasoline the liquid isn't flammable - just the vapors that come off it. Therefore, you need something to ignite the vapors, and a bullet, a stray rock or any obstacle simply won't do that.
Besides, gas tanks usually don't spring links just because they're punctured. Most modern gas tanks are self-sealing, and if they happen to get punctured by a high-caliber bullet, leaking won't be nearly as drastic as Hollywood makes it out to be.
You've seen the scenes before - a car crashes spectacularly, it probably ends up on its side, and a fire starts. But the hero is passed out in the driver's seat, safely buckled to his cushioned chair. As the fire slowly goes from the cabin to the engine to the fuel tank, signaling almost certainly a fiery explosion, the hero wakes up and escapes before the vehicle ascends into smoky bliss.
Dramatic effects aside, an actual car fire won't wait for the protagonist to regain consciousnesses before consuming the vehicle. Once a flame gets going in a car, it will burn hotly and intensely and will most likely take over the whole car in a matter of minutes. And that's not so much to do with the gasoline or the ruptured gas tank. Instead, the foam, plastics, and other materials in the cabin that are extremely flammable will be the cause of the blaze.
In this scene from Zombieland, Columbus and Tallahassee find a Hummer that's been sitting vacantly for an unknown amount of time. But in a stroke of good luck, not only are there loaded machine guns in the back seat, the Hummer starts right up, too!
As the post-apocalyptic genre has taken off so have the rules of gasoline, apparently. In a lot of these movies, the protagonists find cars or fuel drums years or even decades after a disaster. And magically, that fuel still works perfectly when put in a fuel tank. However, the general consensus is that gas will keep in a fuel tank anywhere from a couple months to a year, tops. Gas degrades over time, and its volatile components evaporate over time. This reduces its ability to combust, leading to anything from hard starting to no starting at all.
Unlimited Gas Tanks
Nothing against the latest Mad Max movie, but does it bother anyone else that these huge, flame-throwing cars seem to have unlimited fuel?
Some of these trucks can't be getting more than 3 or 4 mpg. It doesn't make sense that these trucks can drive for miles across a barren desert without stopping for a fill up. However, it is sure entertaining, despite the fact that unlimited gas tanks don't exist (yet).