Weaponized Exhaust



""A reaction drive's efficiency as a weapon is in direct proportion to its efficiency as a drive.""

- The Kzinti Lesson, Larry Niven.

Most jetpacks, rocket boots, and spaceships give off impressive plumes of fiery exhaust when they're moving. For the most part, this exhaust is just there to show that something's happening. But the exhaust of a rocket can also double as a short-ranged weapon, especially during a getaway. Characters with jet boots can perform really effective Goomba Stomps, while starship pilots can cause enormous damage with their drive flames.

Also known as Kzinti Lesson: the more efficient a reaction drive is, the better a weapon it makes. An inversion of the Law of Inverse Recoil, since the recoil in these cases is intentional. Also an inversion of Recoil Boost, which is an exhaustized weapon. A subtrope of Superweapon Surprise. Fartillery is effectively the biological variant of this. See also Backpack Cannon.

Anime and Manga

 * Orguss 02: Young Humongous Mecha mechanic Lean has fallen into the cockpit and is barely holding his own against an enemy pilot. His solution: tackle the other Decimator mecha onto a nearby island, bend its machine gun barrels so it can't counterattack, point his Decimator's Rocket Boots at the enemy's cockpit!
 * In Mobile Suit Gundam 0083: Stardust Memory, Kou gives Gato a face-full of his Gundam's maneuvering thrusters when locked in close combat. This doesn't actually damage Gato's Gundam, but it does blind and distract him.
 * The leader of La Résistance is killed in Mobile Suit Gundam: The 08th MS Team when a Zaku fires it's thrusters in an attempt to escape an ambush. The backwash takes out his entire house, too. And this was entirely by accident and happened mostly because a resistance member in that house fired an anti-tank rocket at it.
 * Mobile Suit Victory Gundam gives us the Victory 2 Gundam, which carries a miniaturized Minovsky Craft System known as the Minovsky Drive System. Not only does this allow it to float in mid-air (unlike other mobile suits which have to use constant thrust to stay aloft), but the exhaust vents in the back expel charged Minovsky particles, the V2's "Wings of Light," which can expand up to one kilometer long. Fun fact: The Wings of Light have the same properties as beam sabers and beam shields.
 * In Mobile Suit Gundam, one luckless Zaku was caught behind White Base as she was taking off and got vaporized by the engines.
 * At the end of the Guyana Highlands arc of G Gundam, Domon knocks over Master Asia's gundam and basically blowtorches Master Gundam away.
 * In one episode of Super Dimension Fortress Macross, Hikaru uses the thrusters on the bottom of his battloid's foot to blast a Zentraedi away from him.
 * In one of the Robotech novels, a Zentraedi uses his battlepod's feet as blowtorches to fight off an Invid scout.
 * In Crest of the Stars, Lafiel kills Baron Febdash the Younger by venting antimatter propellant through the exhaust nozzles of her shuttle - curiously, the Baron's ship is not obliterated when the exhaust hits its hull, while the Baron succumbs to rapid radiation poisoning.
 * In Last Exile Fam the Silver Wing, the giant weapons employed by the Grand Exile are revealed to have been originally intended as engines.

Comic Books

 * Iron Man's first set of stealth armor was so packed with scanners and such that it had no active weaponry (What an Idiot! comes to mind). Thus when faced with attack drones, he had to dig his fingers into the ground and blast with his jetboots.
 * His repulsor stabilizers also count to an extent.
 * In the Firefly comic book "Those Left Behind", this is how the "Hands of Blue" die, being fried in Serenity's exhaust.
 * Seen in at least one X-Men issue where Kitty Pryde, alone in the base underneath Xavier's School for Gifted Youngsters over Christmas, is faced with a seemingly invincible monster that she finally defeats by luring it into the hangar of the team's Blackbird (a modified Lockheed SR-71) and incinerating it with the engines' exhaust.
 * The Irredeemable Ant-Man did this accidentally to a former friend, burning half his face off in the process.

Fan Works

 * In An Entry With a Bang!, the pirates attacking Chicago use the plumes of their Dropship to toast a lot of infantry. The Fusion Torch project aims to use Dropship reactors in this fashion. The weapons' nickname, "Shipkiller", should tell you everything you need to know.
 * In the Firefly fic series Forward, there are several instances where the crew uses Serenity's engines as weapons. In "Business," they lured an Alliance gunboat close enough to fire the engines directly into the bridge section of the vessel, blinding its sensors and heating up the bridge canopy enough that Jayne is able to put an armor-piercing round through it. Later on, in "Adrift" Wash uses the exhaust from the ship's damaged engines to blind a Reaver pursuit craft, and in the "Fourth Interlude" River manages to exploit a flaw in an enemy ship's engines by channeling her ship's exhaust into its intakes, overheating it and causing it to shut down and sending the enemy ship into an uncontrolled spin.
 * In Sleeping with the Girls, in the second Tenchi arc, the SI remembers, almost too late, that standing near a spaceship about to take off is a bad idea. Cue an Oh Crap moment, followed by him running, screaming "KZINTI LESSON! KZINTI LESSON!" over and over. He almost makes it, and the backwash of the ship's takeoff knocks him off of his feet. Not the straightest example of the trope, but shows an understanding of it.

Film

 * Planet of the Apes remake, when Leo uses the crashed Oberon's main thruster to burn the ape army's first wave.
 * The Batmobile's jet engine is used as a weapon in Batman Returns to put the torch on the Fire Breather in the opening fight.
 * In Alien, Ripley uses the lifeboat's exhaust to finally fry the monster.
 * In Indiana Jones and the Kingdom of the Crystal Skull, a bunch of Mooks are chasing Indy around Hangar 51. He gets into some sort of G-force testing rocket, switches it on and fries the lot of them.
 * Hugo Drax attempts to do this to James Bond in Moonraker.
 * At the start of the movie the stolen shuttle does this to its carrier aircraft during its getaway.
 * Richard B. Riddick does this to the alien monsters as the survivors make their getaway at the end of Pitch Black.
 * In RoboCop 3, the title character kills the villain by burning his legs with the exhaust of his Jet Pack, leaving him helpless in the soon to explode building.
 * In Face Off, Agent Archer uses the thrust of a mounted jet engine to send an obvious Stunt Double of Caster Troy flying into a wall.
 * In the Movie version of Iron Man, Tony Stark quickly discovers he can weaponize the repulsor stabilization propulsors in his armor's hands, turning them into effective blasters.
 * In The Rocketeer, Cliff surrenders the Jet Pack to Neville Sinclair... but not without removing the chewing gum that was sealing a fuel leak caused by a stray gunshot earlier in the movie. When Sinclair fires up the Jet Pack to escape, the rocket exhaust ignites the fuel from the leak and turns the device into a bomb.
 * In The Phantom Menace, Anakin takes out a couple of battle droids that were standing next to his thrusters.
 * In Revenge of the Sith, R2-D2 destroys two Super Battle Droids by spewing oil on them, then igniting the oil with his rockets.
 * In Transformers: Revenge of the Fallen, Optimus Prime gains a jetpack upgrade from ; the exhaust can send Megatron through a stone wall.
 * The Daniel Craig version of Casino Royale features an accidental version during the airport chase scene. Miami Police Department squad cars are chasing fuel truck stolen by the bad guy, and chase it across a runway just as a 747 is coming in. The 747 pulls up and misses the fuel truck, but its engine backwash blows one of the police cars about a hundred feet through the air.

Literature
"He had just turned her (Jumpship) Caliban into a half kilometer long particle projector cannon, the biggest damned PPC in the Inner Sphere."
 * In Larry Niven's Known Space, the warlike Kzinti stumble upon a completely demilitarized humanity. They invade, only to find out that reaction drives and solar sail launching lasers are actually pretty good at blowing things up. Surprise! Humans call this "The Kzinti Lesson": "The more efficient a reaction drive, the more effective a weapon it makes." It came as a great shock to the Kzinti, because their telepathic spies kept telling them that human spaceships were unarmed. They were... technically.
 * Taken to absolutely humongous extremes in Mark Geston's novel Lords of the Starship, in which a seven mile long rocket is built to carry humanity away from a war-ravaged Earth. But it's all a horrible trick: when the rocket is finally completed after more than a century a vast battle rages in its shadow between its millions of supporters and opponents. And then the ship slides down the slipway, and turns around until its engines are pointing towards the warring armies... just imagine how big and how hot a seven-mile long spaceship's rocket exhaust would be. It was all part of a plot by an ancient enemy to get revenge and take over the world. What's left of it.
 * In the first Dune novel, the Emperor reports that his Sardukar only escaped with their lives after attacking a Fremen sietch by doing this (he was aghast, and rightly so, that his Super Extra Elite Finest Troops were outfought by a settlement of elders, women and children).
 * In Harry Potter and The Deathly Hallows, Sirius's flying motorbike is upgraded for Hagrid. Included in this is a burst of Dragon breath out the exhaust.
 * As part of the climactic sequence of Sandy Mitchell's Scourge the Heretic, an Inquisition shuttle pilot uses his exhaust to blast the front wall off the bad guys' mansion.
 * In the early Terry Pratchett novel Strata, at one point Marco mentions they could use their ship's engine's fusion flame as a weapon (although this is never actually seen).
 * Unintentionally used by a number of "hot-shot" pilots throughout the X Wing Series, generally resulting in little scars on the hangar floor. Corran Horn also once used an airspeeder's exhaust to help vent an area of toxic gas.
 * The EU also has it that, while the exhaust of capital ships doesn't pose much of a threat to like-sized ships, it can fry unwary fighters.
 * At one point in the Yuuzhan Vong/New Jedi Order series, Vong bioweapons are eating through a capital ship's hull. The fighter pilots then use their exhausts to burn them off without blasting at the ship.
 * The star system of  is actually artificially created with the planets all being giant spaceships with giant repulsors/engines that have been used as weapons.
 * Even more dangerous is Centrepoint Station, which brought the planets into the system in the first place, and can make stars go supernova from light-years away via the same process.
 * Though The Empire's best known civilian massacre was the destruction of Alderaan, the EU documents multiple lesser massacres. In one instance, an Imperial Navy captain turned his cruiser's stern to a mass demonstration and fired his engines, incinerating the protestors.
 * In Alastair Reynolds' Revelation Space, one of the hell-class weapons is possessed by a sentient, alien computer virus and attempts to destroy an inhabited planet; disaster is narrowly averted by hitting it with the exhaust from a Conjoiner Drive.
 * Also used in The Prefect, where the Conjoiner engines of the lighthugger Accompaniment of Shadows are used to destroy the Ruskin-Sartorious habitat.
 * Not exactly exhaust, per se, but the Honor Harrington books have the gravity-control impeller wedge as main spaceship propulsion...which does Really Bad Things to any matter that intersects the field. Normally, this is safetied to a tee; when it isn't, as in when ...uh...just Bad Things, OK?
 * Used in the first of the series (On Basilisk Station) when Honor cripples one of Havenite shuttles that were ready to summon the invasion fleet.
 * This is how countermissiles work too. They don't have warheads; they just hit the impeller wedge of enemy missiles with their own wedge, destroying both with the feedback on their drives.
 * The trope is also effectively Played With given that these wedges with their horrifying capacity for destruction are primarily used as shields when they aren't used for propulsion, given that they effectively cover the ship completley from the top and bottom. This becomes very important in Mission of Honor when a group of ships have to use their wedges to try and protect the planets below from falling debris during an attack.
 * In David Weber's Dahak series, the gravitational "backwash" from the warp drive is used to blow up a star. Fun times abound when your planetoid-sized ships use artificial black holes as propulsion.
 * In Sergey Lukyanenko's Line of Delirium novel, the main characters are infiltrating/storming a military orbital platform. Upon receiving a coded signal, their ship, sitting in the hangar bay, uses it's gravity engine to "push out" the hangar bay doors and then activates the plasma engines to fry the combat droids guarding it.
 * In Arthur C. Clarke's Earthlight, the particle beam weapons are directly derived from spacecraft ion drives, which are dangerous enough in their own right.
 * In E. E. "Doc" Smith's Masters of the Vortex, there's a chapter named for this -- "Driving Jets Are Weapons".
 * Given when it was written (1960), this example should be a candidate for trope namer.
 * (For those who want to know the details: the ship is dived headlong towards the enemy base, and then flipped end-for-end and full thrust applied to cancel out the velocity gained. The shields are overloaded and collapse, and then the target follows. Twice.)
 * The BattleTech novel "Operation Excalibur" demonstrates this trope when the Gray Death Legion mercenary commander Grayson Death Carlyle creatively positions a hijacked Jumpship to point the exhaust end of its drive at one of the setting's extremely rare deep space recharging stations. It works as a shock and stalling tactic because such stations are considered inviolate, and it's an accepted rule of space to point that end of the ship away from anything you want to keep in one piece. The moment of realization for all parties involved who didn't know about the plan beforehand is capped by an utterly priceless line:


 * Also used in the climax of the novel "I Am Jade Falcon." The aging Falcon Mechwarrior Joanna is trapped in a fallen Summoner, having lost a leg in battle and with her weapons nonfunctional.
 * Used as a particularly gruesome method of execution in Scarecrow by Matthew Reilly, with the afterburner of a tied-down fighter jet.
 * In Georgy Gurevich Overtake Only the protagonists who've just stolen an old photonic rocket from a museum (it's a long story) deal with the pursuers by pointing the reflector at them and starting the engine, evaporating in the process not only them, but a good chunk of the space station to which the rocket was docked as well.
 * In the James Bond novel Moonraker, Drax attempts to dispose of Bond by placing him beneath the exhausts of the eponymous rocket. It was one of the few scenes from the novel to make it into the movie.
 * In When Worlds Collide, when a crazed army of survivors attacks the site where [The Ark the Arks]] are being built, things look bleak until one of the main characters starts up the almost-complete first Ark, sets the engine to "1 G", and floats over the attacking hordes in blowtorch mode.
 * In Poul Anderson's Harvest of Stars, there is a treaty banning weapons in space. When the main characters get into a space battle with the bad guys, it is essentially a game of cat and mouse, each trying to slash the other with their exhausts while avoiding getting slashed themselves.
 * Mack Maloney's Wingman series has an air pirate early on threaten to torture Hawk Hunter by strapping his face to the engine of his fighter and slowly turning up the power. While he never goes through with this threat, in a later book (Freedom Express) Hawk kills an escaping baddie by flying his Harrier over the jeep and cooking them until the obese lieutenant bursts.
 * Used in Aeons Child in Robert Reed - a starship's fusion rocket is disassembled, brought inside the Great Ship, and reassembled to be used as a last-ditch weapon to purge a chamber of a hostile Gaian entity.

Live-Action TV
"Zoe: Ain't no way they can come around in time to follow us now."
 * In the Firefly Pilot, Wash uses Serenity's exhaust flame to ignite a planet's atmosphere as a way to disable/distract a Reaver ship after performing a "Crazy Ivan".


 * Mal also intended to use the exhaust (both the flames and more importantly the physical pressure) against Burgess' troops in "Heart of Gold", but that plan never got off the ground.
 * A Space: 1999 episode, "Voyager's Return," concerned a probe whose drive system was lethal.
 * In an Andromeda episode, the crew encounters an ancient Earth STL ship, which uses its massive fusion engine to rapidly accelerate to near-light speeds (it was built before humans learned about slipstream). In a pinch, this defenseless ship can use the same engine to incinerate enemy ships at the cost of precious fuel.
 * Played with in Top Gear with a car shooting paintballs from its exhaust. It proved a highly effective weapon when one hit Clarkson quite painfully.

Tabletop Games

 * In BattleTech, the massive Dropships are capable of razing anything anywhere nearby in a nuclear hellstorm of fusion reactor exhaust when they begin to lift off the ground to head to orbit.
 * GURPS: Space lists the offensive potential of several engines. Because GURPS assumes that most engines will not have particularly coherent exhaust streams they're relatively weak compared to normal armaments.
 * The nuclear jetpack blasts superheated radioactive exhaust at everyone below it. Why anyone would wear such a thing is a different issue.
 * A BBEG using it to escape the heroes?
 * SPI's classic boardgame StarForce uses a relative of this trope. In the game, "TeleShips" move FTL by teleportation. They fight by throwing random teleport windows at each other.
 * D20 Modern mentions this in the descriptions for starship engines. Rules aren't given for it, since it's an unorthodox (and clever) tactic.
 * In Palladium's Rifts sourcebook "Mechanoids", Overlords and Oracles (evil, building sized robots with a bend for human extermination) are packed full of weapons, but still like the elegant process of flying a few meters over unprotected humans. Crispy bacon.

Web Comics

 * James from The Adventures of Dr. McNinja, the leader of our good doctor's college Vigilante Club. He invented jet boots and used them to kick people and set them on fire.
 * Inverted in 'Schlock Mercenary, where handheld plasma guns also have a plasma rocket setting.
 * An engineer in Vexxarr pointed out that since by definition hot plasma goes in the direction exactly opposite to the ship' acceleration, this also solves a fundamental philosophical dilemma -- "fight or flight".
 * In Basic Instructions, resident superhero Rocket Hat has been known to use his rockets in this manner.

Web Original

 * Chakona Space: Neal Foster discusses this with his young engineering trainees after they encounter the Blowfish.

Video Games
""Antiprotons are injected into a reaction chamber filled with hydrogen. The resulting matter-antimatter annihilation provides unmatched motive power. The exhaust of antiproton drives is measured in millions of degrees Celsius; any vessel caught behind them will melt like wax in a blowtorch.""
 * You can use this in Gates of Zendocon on the Atari Lynx.
 * In the Battlefield 2 mod Project Reality you can kill players with the backblaster of rocket launchers. However, you are more likely going to kill a teammate than an enemy player, as very few players are going to stand still for you to cook them.
 * PTX-40A in Tatsunoko vs. Capcom uses its thrusters as attacks in some of its command normals.
 * In the Irem Shoot'Em Up Image Fight, changing gears causes a tiny burst of exhaust that can do some damage in a pinch.
 * Irem loves this trope. Special mention goes to the first boss of R-Type Delta; its attack pattern alternates between blasting a barrage of building-leveling weaponry at the player's ship and...retreating. The player has no choice but to give chase, and evade the two large flames from the boss' rocket engines. The engines can be damaged to give the player more room to maneuver.
 * In Final, on the other hand, the line of ships starting with the Daedalus is capable of doing this to enemy units; shifting your speed up or down with any ship sets off a jet of exhaust, these ships just give off a bigger one that can frag mooks!
 * In Blast Works: Build, Trade, Destroy, certain enemies use exhaust which can destroy your ship and, when taken as your own, can save the moment as a very short range weapon.
 * Robo-Ky from Guilty Gear has a heat gauge, and a good deal of his moves make it climb. If he overheats he explodes and damages himself and gives his opponent an opening. To prevent this, one of what would be his normal moves (his forward heavy slash) makes him vent steam, which he must do regularly to keep the heat under control. Of course, the steam itself is more potent the more heat he builds up first, and venting when he's seconds away from overheating creates a gigantic plume that does respectable damage and sets his opponent on fire.
 * The Thraddash in Star Control II have afterburners on their ships which accelerate the ship and leave a fiery trail in their wake. This tends to deal more damage to enemy ships than the supposed main weapon.
 * The game Platform gives you jetpacks with deadly exhaust. Except the only thing you can kill with it is your partner.
 * The shmup Battle Garegga has the boss Black Heart, one of whose attacks is moving down to you and letting the afterburners flare up.
 * This is a common attack in shmup games, the third boss of Ray Force and the Twin black MIGS boss of Aero Fighters do the same thing.
 * One of Gradius Gaiden's stage 9 midbosses, Boost Core, has harmless exhaust...but only on the first loop. From the second loop onwards, its exhaust is lethal.
 * The second boss in Wario Land Shake It used the exhaust flames of his race car as an attack against Wario if Wario came too close (in the second stage of the battle, he actually lowered his car to the ground to burn Wario with the flames if Wario tried to go past him).
 * In One Must Fall 2097, the Pyros robot is equipped with rocket boosters that double as flamethrowers. One particular special move has the Pyros use the boosters to reverse direction in midair, damaging any close-by opponent in the process.
 * Several of R.O.B.'s attacks in Super Smash Bros.. Brawl involve this. Fox, Falco, and Wolf's jetpacks can also damage other players.
 * In Sonic The Hedgehog 3 and Sonic And Knuckles, all of the stage bosses that fly by means of rockets can injure Sonic with said rockets. Few of them do so intentionally, however.
 * Vectorman's foot jets that allow him to Double Jump also allow him to deal damage to his enemies via the Goomba Stomp method.
 * Space RTS Homeworld has an example of this trope in its Bomber strike craft. The game manual quips that the player race scientists realized that the most powerful directed energy system of the strike craft was their own fusion drive system. Hence they made a strike craft that can divert part of its drive thrust into very powerful plasma bombs.
 * Well of course it was, since they used mass drivers.
 * In Dead Space a certain boss creature that constantly regenerates can only be gotten permanently rid of by incinerating it with the exhaust jets of a shuttle.
 * In Metal Gear Solid 2 the harrier boss burns you with its exhaust as one of its attacks.
 * Kirby's Jet ability has this when it's charging power, as well as when Kirby is attacking, at least in Kirby Super Star.
 * In the DS remake, it also causes damage while using it to hover, which is a surprisingly effective method of disposing of bosses and enemies alike at times.
 * In Half-Life, a tentacle monster is living inside one of Black Mesa's rocket test chambers. Kill It with Fire is the obvious solution.
 * In G-Darius, the boss "Death Wings", a Humongous Mecha manta ray tries to torch the silver hawks via exhaust from its manta ray "wings".
 * Mass Effect has a codex entry noting that a dreadnought's exhaust can melt through practically anything (we never see it used, though).
 * Not just dreadnoughts; any ship's thrusters can melt armor "like wax under a blowtorch".
 * According to the (unofficial) Wikia;


 * The Normandy generates Mass Effect fields that it "falls" into, in order to mask it's emissions when in stealth mode. Just imagine what multiple, sufficiently powerful directed Mass Effect fields could do under the right circumstances... oh, wait, that's suggested here, albeit in the form of shields rather than engines. Still!
 * Finally played straight in the Arrival DLC, when Shepard and Dr. Kenson escape from the Batarian prison, some guards arrive a bit late to stop them... and find themselves on the wrong end of their escape shuttle.
 * The airship levels in Super Mario Bros 3 have flamethrowers on the outsides of ships that are probably meant to be thrusters.
 * In Star Wars: X-Wing vs. TIE Fighter and its later games, flying too close to a capital ship's rear thrusters causes damage. If you chose a non-engine location as a staging point for a "safe" point-blank attack, it would use a weapon jamming beam.
 * In The Bouncer, Mugetsu is killed by being dropped off the side of an airship, into its booster jets.
 * Though it naturally doesn't come up in gameplay, ISA cruisers in Killzone can use their nuclear-powered beam thrusters as weapons, too.
 * In Disgaea units that learn to use guns gain the "Proximal Shot" ability which allows them to invoke this trope while using their firearm as an impromptu rocket engine.
 * This is a surprisingly effective way to kill someone if your clones lack better weaponry (and sometimes even when they do due to the wonky physics making them ineffective) in Cortex Command.
 * It's also quite effective at killing enemy dropships when piloting a dropship yourself. Being that the ships are unarmed and with very weakly armored engines, the best course of action is to position your ship so one of its engines is exhausting on top of one of the engines of the enemy dropship, and hit the throttle.
 * In MadWorld, a couple stages have jet engines that will instantly kill enemies when they are thrown into them. Now, that's all well and good in the zone that is a three-way Shout-Out to Star Wars, Star Trek and Battlestar Galactica, but a random fighter plane attached to a wall in the middle of the Casino zone is a bit much. What would XIII think?
 * Of all games, Einhander has one for the player character. By changing speed, your craft gives out a burst of exhaust, which along with the manipulator arm may be the deadliest weapons in the game. Because of this, it's possible to beat a level without firing a shot. Elsewhere in the game, the booster rockets for the satellite can kill you if you fly behind them.
 * The Star Soldier series uses this variant as well. At times, a ring-shaped enemy ship will enclose you, and the fastest way to dispatch it is to mash the "speed change" button while firing.
 * Word of God on Sword of the Stars states that the devs had considered this idea, but then threw it into the reject pile for detracting from the fun by having too much potential for Friendly Fireproof.
 * Inverted in the Super Robot Wars franchise with the Hagane: On more than one occasion, it has used its Wave Motion Gun with the gravity brake off as an emergency escape tactic.
 * Final Fantasy XIII has Sazh's Eidolon, Brynhildr, do this in Gestalt Mode with her Múspell Flame. Since her elemental affinity is fire, it's more that appropriate.
 * Sebulba in Star Wars: Episode 1 Racer has this, just like in the movie.
 * The gunship in Perfect Dark Zero attacks with its engine flames after it Turns Red.
 * In James Bond 007: Nightfire, Bond kills off Kiko with the exhaust of a Space Shuttle owned by Phoenix.

Western Animation

 * Inverted by skilled firebenders in Avatar: The Last Airbender, who are able to send jets of fire out their feet or hands, allowing flight.
 * The Music Meister sends his thralls to their deaths by having them line-dance into a rocket engine's exhaust. Fortunately Batman intervenes.
 * Really bizarre example occurs in Lilo and Stitch. Stitch is on the back of the evil shark alien's ship, and to attack him, the alien pushes a button that causes the thrusters to turn inward and blast Stitch (who is fine, being Nigh Invulnerable and in a Disney movie). Why would he even have a button that does that?!
 * Space Barnacles? Or to cut tow cables that might be attached. Or to 'terminate' captured targets.
 * Same reason our Earth toasters have a setting that turns bread into inedible briquettes, I guess.
 * That setting is for muffins.
 * So it's settled, the engines were for muffins.
 * The engines move around a lot anyway; presumably the vectored exhaust helps control the ship. It's not too big a leap to assume that such a system would have a manual override.
 * In one episode of Batman Beyond, Terry didn't use his jet boots directly as a weapon, but he did use them to propel a crate at someone.
 * Inverted in Up, where the leaf-blower Carl had previously employed as a "weapon" of humiliation, blowing blasts of air in the faces of annoying neighbors, gets re-purposed as a means of propulsion by Russell, who's tied a bunch of balloons to himself and drifted away.
 * Transformers Animated: Prowl uses his jetpack to burn a Space Barnacle monster in "Nature Calls".

Real Life

 * MythBusters had a jumbo jet's engines overturn a taxi, a schoolbus, and a smaller aircraft.
 * They also set their own shop on fire testing a rocket engine indoors. Don't Try This At Home.
 * Top Gear did the same stunt at one point, using a saloon car and then a Citroen 2CV.
 * The Convair X-6 was a prototype of atomic-fueled bomber releases so much radioactivity on its path, to make it a weapon itself. The project has been closed as there was no way to reduce the emission when in friendly territory.
 * The Supersonic Low Altitude Missile (also known as "The Flying Crowbar", or more formally Project Pluto) would have been an unmanned nuclear-armed cruise missile with an unshielded nuclear ramjet leaving a deadly trail of fallout in its wake. Part of the plan was to have the SLAM run a pattern over the target country after it had delivered its bombs, intentionally irradiating the land.
 * Inverted with the Orion Project, which would intentionally launch thermonuclear bombs out the back and catching the blast with a pusher plate on massive shock absorbers. Call it Exhaustized Weapons. Or not.
 * The only space station ever to be really armed (an old Soviet station that had a machine gun on it) ran into problems with the reaction from the bullets pushing it out of its correct orbit.
 * Thanks to Newton's laws, it's been argued that any kind of drive powerful enough to accelerate a large ship to appreciable speeds would make a phenomenal weapon against said ship's enemies.
 * Consider the following: to get the space shuttle into orbit, it takes about 10 terajoules of energy. That's enough to boil over 1000 tons of iron, all delivered in eight minutes. That's an average of 20 gigawatts of power. For comparison, when people talk about possible real-world directed energy weapons, they talk in tens of kilowatts. A laser is more directed and longer ranged, but even the relatively wimpy chemical rockets used to get into orbit deliver about two hundred thousand to two million times as much power.
 * The earliest war rockets tended to work this way. When Tippoo Sultan used them against the British in the Indian wars of the late 18th century, rockets tended to do more damage if you dropped them in a confined space and they ricocheted off the walls burning people with their exhaust than if you used them the conventional way. This was partly because they were too inaccurate to be directly aimed at targets, but another thing that played into it was the fact that such rockets couldn't really carry an explosive payload either.
 * Almost all rocket-propelled weapons have a hazardous zone behind them. Size of that zone varies with weapon, but it is a very bad idea to stand behind an MLRS (or a humble RPG operator) during launch. Operators of man-portable rocket-propelled weapons are told not to fire their weapons if they have a wall behind their back.
 * Averted by the German Armbrust and French/Canadian Eryx antitank launchers. The Armbrust exhausts a relatively gentle puff of plastic flakes while the exhaust gases are captured in the tube by sealing pistons. The Eryx has a tiny charge to kick the missile out of the tube, then the main rocket ignites at a safe distance. Both launchers can be used in enclosed spaces with no harm to the crew.
 * Also partially averted by the AT 4-CS, which uses a salt-water counter-mass to absorb much of the blast.
 * The General Dynamics F-111 was well known for dump-and-burn performances. Because the main fuel dump valve was located between the exhausts, opening it and bumping the afterburners would leave a spectacular trail of flame. This was a legitimate tactic for confusing heat-seeking missiles and an airshow specialty of the Royal Australian Air Force, even being performed at the 2000 Sydney Olympics closing ceremony.
 * Also applies to warp drives - the Alucbierre Drive would fry whatever you stopped at. Then again it'd make interstellar wars pretty easy...
 * The Big Wind is an old tank chassis fitted with surplus jet engines, built to fight oil well fires by blowing them out.