To salute A Good Day to Die Hard, we take a walk down Molotov Lane and recall the franchise’s three best explosions. But how realistic are they? FBI bomb tech Kevin Miles tells us whether or not the kablooies are just plain phooey.
Building Explosion: Die Hard
Wait! That elevator explosion didn’t kill all the terrorists. The main goon is still alive and wants to blow the roof off this place — literally. But right before he ignites the TNT, McClane ties a fire hose around his waist, and he jumps off the roof as it goes kablooey. The hose protects him from falling to his death, but not from the heavy eyerolls in the audience.
Bomb Tech: “I don’t know how much TNT was up there, but any amount greater than 15 or 20 pounds would have resulted in McClane, the hose and the spool being blown off the roof all together. Plus, there is a gigantic fireball. Real explosions do not generate that much fire, unless it’s enhanced with gasoline or some other inflammable substance.”
Subway Explosion: Die Hard: With A Vengeance
What appears to be a crazy homeless man proselytizing about Doomsday on the subway (dime a dozen) is really just a dirty John McClane, frantically trying to find a bomb hidden on the 3 train. He discovers the explosive and then kicks out a window, tossing it out of the train right as it detonates. Fire, smoke and a derailed train come barreling into Wall Street station, yet miraculously, no one dies.
Bomb Tech: “Everyone would have been blown to bits. The subway tunnel is the worst place for an explosion to happen, because the pressure wave generated by the detonation has nowhere to go. It’s ten times as worse as a bomb in an open space.”
Jumbo Jet Explosion: Die Hard 2: Die Harder
While Det. John McClane is fighting bad guys on the wing of a moving jumbo jet about to take off, he opens the fuel door, and a stream of flammable liquid pours out. McClane is knocked off the wing, and right before the plane takes off he pulls out his trusty Zippo lighter, lights the stream of gasoline on fire, and makes the airplane go boom. Great product placement, Zippo!
Bomb tech: “While it’s possible, it’s very unlikely that the trail of fuel would move up to the wing. With the plane doing 180 knots down the runway and the engine on max for takeoff, the exhaust and wash would serve to blow out the fire.”
Helicopter/Car Explosion: Live Free or Die Hard
When a gang of cyber-terrorists leads McClane and his new sidekick (played by Justin Long) into the path of an assault helicopter, our hero decides to take down the chopper by driving his car into a tollbooth, effectively launching it into the air, where it crashes into the helicopter in a glorious display of destruction. The only thing less believable is Justin Long as his partner.
“Believe it or not, this could actually happen. However, the speed required for McClane’s car to achieve that height would be so fast that he would not have survived his jump-and-roll out of the car.”
Elevator Explosion: Die Hard
To thwart German terrorists at Nakatomi Plaza, McClane swipes a block of their C-4 explosives and pulls a MacGyver, transforming it into a makeshift bomb by sandwiching it between an office chair and a computer. Then he throws it down an elevator shaft, and it detonates upon impact, killing the bad guys and becoming the most impressive use of office supplies ever.
Bomb tech: “The wires coming out of the C4 caps are twisted together. Caps only work when the wires are separated and connected to a power source, and there isn’t one. Falling 50 stories might set them off, but it is highly improbable.”