Vapor Trail

A vehicle is damaged and leaking fuel. The hero (and it is almost always the hero) ignites the trail of fuel, causing a line of flame to streak after the fleeing vehicle. The fire catches up to the vehicle, ignites the fuel tank and causes the vehicle to go up in an impressive fireball.

Compare Powder Trail. Also remotely related to the one of worst problems with Stealth in Space.

Nothing to do with a lack of a paper trail where there ought to be one. Also not to be confused with either the Rush album or the Crystal Method song entitled Vapor Trails.

Examples of Vapor Trail include:

Comic Books

In Tintin in the Land of the Soviets, the streak of flame almost catches up with Tintin's car. Then the fuel runs out.
- Definitely not a case of Truth in Television: The fuel-air vapor in the empty tank would actually be a lot more flammable than liquid fuel.
Jonah Hex pulls one in Hex #18, lighting the fuel with his trusty cigarillo.
Marv does this to a wrecked car in the Sin City story, Just Another Saturday Night.
Happens in DC Retroactive: Batman - The 90's when a cabbie drops a lit cigarette into a pool of gasoline leaking from his wrecked cab.

Film

Done by James Bond to a fuel tanker in Licence to Kill.
Done by John McClane to a jet in Die Hard 2. It's worse in this case, as the Mythbusters proved that jet fuel is actually really hard to light in a liquid state - especially in a snowstorm. Yippee ki-yay, motherfucker.
Lethal Weapon 3
Happens accidentally to one team of racers in The Gumball Rally.
In The Stupids, the pursuer shot Stanley's gas tank. Stanley proceeded to light the trail on fire, igniting the pursuer's car. Of course, he had no idea what was going on.
This is how Porter exacts his final vengeance on all the bad guys in the movie Payback. "You were right not to trust me."
The final scene of Spy Fiction.
Spells the end for the racist redneck in The Final Destination.
An exploding aircraft in Speed.
In X Men Origins Wolverine, Wolvie ignites a spark with his claws. The fire travels up the trail of fuel leaking from Agent Zero's downed helicopter. Kerflooey.
In Torque, a vapor trail chases down a bike moving several hundred mph.

Literature

One of W.E. Johns' Biggles adventures features this. An air pirate encounters Biggles' deHavilland Mosquito fighter variant (four 20mm cannon plus or minus four .303 machine guns) in place of the unarmed bomber-turned-civilian-transport he'd planned to attack. When Biggles nails his opponent's fuel tank, the fellow panics and attempts to return fire through his own vapour trail. Because he's using tracer rounds, which basically trail a stream of fire behind them for up to six hundred yards... well, you can guess the rest.

Live Action TV

Tested (and busted) on MythBusters.
- A trail of gasoline can be set on fire, but if the vehicle is moving faster than about five miles an hour, the flame will never catch up with it, and even if it did, the gas tank won't explode.
- Fuels other than gasoline, such as diesel or jet fuel, just can't be ignited if lying in a pool on the ground.
Farscape did this one too.
Alarm Fuer Cobra 11 uses this occasionally.
In the Angel episode "Redefinition", Angel sets Darla and Dru on fire at the end by smoking a cigarette and throwing it in to a trail of gasoline.

Music Videos

Happens in Music Videos for Radiohead's "Karma Police" and The Arctic Monkeys' "Florescent Adolescent".

Newspaper Comics

Happens to Measles' car in Dick Tracy. For added drama, Tracy was trapped clinging to the underside of the car at the time.

Video Games

In Bayonetta, the title character slams a tanker into the defeated Cardinal Virtue of Temperance by way of another angel and creates the leak via a fountain statue that pisses the gasoline all over the poor bastard for that extra sadistic touch. It doesn't work. When the fire goes out after a brief second, Bayonetta just heaves a sigh and does it the "boring" way.

Western Animation

In the Justice League episode "Fury", fallen power lines ignite a trail of spilled fuel leading to a downed helicopter.
On the Donald Duck cartoon "The Flying Jalopy", the villain cuts the fuel line of Donald's airplane and lights the trail in midair, which Don then tries to outrun.