Sometimes in video games lacking the Law of Inverse Recoil, firing rapidly in a direction opposite of where you want to go will give you a good push sideways or even upward.
While not possible with Real Life hand-held firearms, there's a grain of Truth in Television — a few of the most powerful mounted machine guns actually exert enough force to propel a vehicle, although they would also destroy large swaths of countryside in the process.
- The maxed out machine gun in Cave Story has such a high recoil that firing downwards will propel you upward for as long as ammo lasts. On the flipside, firing upwards pushes you downwards when you try to jump.
- If you acquire an optional upgrade that increases your ammo replenishment rate and are smart with your ammo, you can fly indefinitely with it.
- In Devil May Cry, leaping in the air and firing the pistols to keep yourself airborne is a strategy noted in the manual.
- BioForge has a Gravity Screw room where you orbit helplessly around an object in the middle. The only way to move around is to use your gun.
- In The Legend of Zelda: The Minish Cap, you have to use the Gust Jar in a few areas to move a floating platform around like a boat. Normally the jar sucks in items when it's being used, but also produces one big puff when stopped. The recoil is what moves the platform, rather than the suction.
- In Spelunky it's possible, when timed right, to use any gun's recoil to boost the height of your jump to go up three spaces instead of two. With the spring boots, it's then possible to go jump up to four spaces. This can be very useful for saving ropes when you do not have the climbing gloves or jetpack.
- Risky's Cannon in Shantae and the Pirate's Curse is used by Shantae to perform multiple jumps in mid-air by firing it downwards.
- In Sundered, the Valkyrie Cannon generates enough recoil to throw Eshe a good twenty feet backward with every shot. This is a perfect way to avoid attacks and break free of a horde of enemies.
- Early versions of the "Combat Construction" mod for Tribes 2 had recoil all on the weapons. On the vast majority of them, the recoil was negligible. However, there was a fully automatic M60 machine gun, which had quite a large recoil, a massive magazine, and a constant stream of bullets. It effectively allowed you to fly around the map at a hundred km∕h, when the average top speed for players in the mod was a tenth of that.
- Crysis's engine supports true weapon recoil, which has important effects in space. One of its mods, Mechwarrior: Living Legends, features a ground troop weapon (the Man-Pack PPC) that creates enough recoil with one shot as to provide you a good 15 km∕h in the opposite direction. The low gravity map provides extended entertainment when using this weapon, but it is regardless useful as an extra manoeuvring tool.
- All weapons in Marathon had some recoil. In low-gravity levels you could use the flamethrower as a makeshift jetpack. You could also use the recoil from the grenade or rocket launcher to reach otherwise inaccessible ledges or bypass significant parts of levels, although in many cases this overlapped with Rocket Jumping.
- By changing the physics model in Anvil you can also make the flamethrower act as an actual jetpack (give it high negative recoil) or change the pistol's firing animation to the MA-75B's to make it fully automatic. The combined recoil of each shot can allow you to hover with one pistol, or actually fly into the air (or through walls) with two.
- In Team Fortress 2, one of the Scout's unlockable weapons is a shotgun called "The Force-A-Nature" that has such ridiculous recoil that the player is also knocked back when it's fired in mid-air and can provide a third jump on top of the Scout's usual double-jump.
- Strangely, the Pyro's regular flamethrower alternate fire, the airblast, can reflect projectiles (including arrows!) but does not push the player around, only enemies. This is probably because the Pyro would get 10 extra jumps if the airblast did have recoil. Although, with proper timing, the Pyro is able to use the airblast to Rocket Jump off enemy rockets and grenades.
- Cube does this nicely vertically and horizontally. Combined with Rocket Jumping, you can reach heights unbelievable to the uninitiated.
- In Half-Life, the Tau Cannon has enough recoil to send a player across the map and is put to good use in the fastest speedruns.
- And very notorious in Half-Life Deathmatch.
- On the Killing Floor map Moonbase, the low gravity allows for all shotguns to provide faster movement and, if the player has an automatic shotgun, an impromptu jet pack, if they are fired while the character is in the air. No matter which shotgun you use, you can easily outrun any specimen using a recoil boost.
- In Overwatch, Ashe's Coach Gun flings enemies away while flinging Ashe just as far backwards. It's useful to create distance as well as to quickly reach high ground by firing it at the ground and using it to "jump".
- In Sengoku Basara, it's possible for Nobunaga to use the recoil of his shotgun to essentially fly.
- The later Samurai Warriors games gave Masamune Date a pair of flintlock pistols as part of his arsenal. It is possible to rapid-fire them as part of his air attack, allowing him to extend the range on his jumps.
- Squall in Dissidia Final Fantasy utilizes this in some of his attacks. They vary from giving a heel drop more kick, to repeatedly using the recoil to 'push' his weapon out of his opponent only to quickly thrust it back in, to propelling him forward at blistering speeds.
- In Glider PRO, rubber bands can be used this way to great effect (especially to break loose from cobwebs), though the two-shot limit complicates things somewhat.
- Jetpack Joyride brings this to its logical conclusion, a machinegun jetpack.
- Hedgewars: The Sine Gun has some crazy recoil that can easily get you over an obstacle when shot downward. Just don't shoot it straight up or you'll take fall damage from the acceleration.
- In Wipeout 2097. If you fire the machine gun using the machine gun cheat, it pushes the craft backward. It's used to great effect if you rotate to the wrong way and destroy all the craft in your way.
- In War Thunder, the recoil effect is too small to matter while in flight, but when landing it can be exploited to slow down slightly faster. Obviously not a realistic thing to do, but since the game doesn't model in the friendly personnel at airfields who would be in your line of fire there's no downside to it.
- In MapleStory, the Gunslinger class has a skill called Recoil Shot to help propel itself backwards. Cannoneers can do this horizontally with Blast Back, or vertically with Cannon Jump. Blasters have Detonate, which can be used for both vertical and horizontal propulsion.
- The World of Warcraft Redridge quest line features a moment where the re-assembled team of veterans travels across the lake to the orc fortress - and the team mage uses a fire spell aimed to the back of the boat as a makeshift jet engine.
- In Elsword, the character Chung(or Lacher in japan) does this with his BFG . His "Shooting Guardian" promotion and its subsequent upgrade expand on this, getting additional air time with handgun shots.
- In Guild Wars 2, the Engineer's Rifle has several skills like this. Overcharged Shot knocks the enemy away, but with such force that it blasts the Engineer back as well. Jump Shot has the Engineer point the rifle at the ground and use a high-powered shot to blast themselves through the air.
- In Phantasy Star Online 2, the Rodeo Drive photon arte lets you ride a launcher for a few seconds by utilizing this. It's mostly meant to be used as an attack, however, and despite looking rather silly, is actually the most powerful move in the weapon's arsenal.
- In the SNES Duck Dodgers game, firing your blaster in the opposite direction helps you make extra-long jumps.
- Duke Nukem II had the flame thrower. It'll propel you upward if you fire it downward.
- Firing the Plasma Gun in Purple blasts you off to the opposite direction, allowing to jump over wide gaps by firing downwards.
- Several of the secrets in Iji can only be accessed using the horizontal recoil of The Nuke.
- In The Adventures Of Rad Gravity, this is the only way to move around in the asteroid belt.
- No Time to Explain has its entire gameplay built around this — you have to use the recoil from your huge laser (or shotgun) to Rocket Jump to platforms.
- In Freedom Planet, Milla Basset's charged cube beam attack has significant recoil. Speedrunners have figured out how to turn that recoil into motive force to accelerate Milla to the point where she can actually keep pace with Lilac and Carol.
- Broforce has both The Brominator and Bro Caesar with their miniguns that propel them the opposite way they're facing and their Special Command, Minigun Leap, launches them with the recoil to slam down onto anyone stupid enough to be in their way.
- The Bazooka in Wuppo will push you slightly in the other direction when a charged shot is fired. The same goes for every shot fired by the Newspaper Cannon.
- This is accomplished with a melee weapon in Mega Man Zero 3. The aptly-named Recoil Rod's Charged Attack, when aimed at a wall in front of Zero, sends Zero flying straight. If pointed downwards, it will propel Zero up in a Super Jump.
- In Dawn of War III, the Orks have the Supa Kannon in mission 4. It works as advertised, but it's so hilariously overpowered that its own recoil launches it backwards a kilometer. You end up firing it several times to get it back to home base.
- In NetHack, you can use the recoil of throwing things to move about when levitating.
- ADOM has a low friction ice level, where you can't walk. Moving around there is done exclusively by the way of thrown item recoil boost (and kicking off walls). Getting recoil boost off a potion of uselessness is its only use - and for subverting the name, the gods themselves reward you.
- The 2D platform shooter Soldat has a minigun that has a very high recoil and provides leverage if fired downwards.
- Taken to its logical extreme in the retro flash game Maverick, where the point of the game is to travel around on the recoil of your two six-shooters. Which naturally have Bottomless Magazines.
- Liero had ridiculous recoil on several weapons. Sometimes it was even more efficient to recoil-jump than using the Grappling Hook!
- In Touhou: Imperishable Night, Marisa's Last Word spellcard "Blazing Star" is her using Master Spark in this fashion. While shooting at you. She also uses it this way in the fighting games.
- In each of the first two Super Robot Wars Original Generation games, the Hagane fired its Tronium Cannon with the compensators disabled, allowing the severely damaged ship to escape the map from the recoil. The first time, it's done to breach the artificial planet Neviim by firing point blank. The second is generally considered a CMoA for Captain Daitetsu Minase, especially considering that he was literally dying from a mortal wound at the time.
- Grand Theft Auto III and Grand Theft Auto: Vice City have the Rhino, a working tank. If you rotate the turret to face behind you, firing a shot propels you forwards. Timing this right can give you a much higher top speed, and, with the correct cheat, allow you to fly. In a tank. Sadly, because of changes in the control scheme, the same trick is pretty much impossible to pull off in Grand Theft Auto: San Andreas without the player crashing the Rhino into a wall.
- Cortex Command provides several weapons with nice recoil. The heavy digger can be used with very light actors (such as skeletons) to lift them in the air or cushion their fall. Some guns have been designed that have so much recoil that they must be fired with a massive mech; you can fire them with any actor, but most will just explode.
- In Space Engineers, the gatling guns on small ships and the handheld assault rifle will send the user/ship flying backwards with sustained fire.
- The Druuge Mauler in Star Control II is basically a giant cannon with a control pod attached to one side. The cannon produces far and away more thrust than the ship's actual engine. Strangely, none of the other ships, including those that use projectile weapons, exhibit any form of weapon-induced recoil.
Non-video game examples:
- In Cowboy Bebop episode "Heavy Metal Queen", Spike propels himself shooting his pistol after jumping loose in a zero-gravity space.
- While not technically being a gun, Dragon Ball's Kamehameha is occasionally used for this purpose:
- The first instance of this is Master Roshi, the inventor of the technique, using it in his match against Krillin to prevent a ring-out by soaring over the crowd. Goku considers using the same trick in his fight against Roshi, but decides to spin his tail around like a helicopter instead and use the energy for a later time.note
- Goku would use the trick in similar ways at the 22nd Tenkaichi Budokai against Krillin and then Tien. Against Krillin he used it as part of a combo where jumps into the air, propells himself at his opponent at incredible speed. He then delivers a colossal right hook that sends Krillin flying across the arena, followed up by a flying knee into his stomach to prevent a ring out. When Goku used it on Tien, both are free-falling and the first to touch the ground will lose. Goku fires the Kamehameha twice in succession: one to headbutt into Tien, knocking him down so he couldn't fly and a second using his last bit of energy to gain some more height and ensure Tien will hit the ground first. Goku ends up losing anyway, because he hits a truck before Tien gets to the ground.
- After King Piccolo breaks both of Goku's legs and his left arm to prevent him from being able to fight. Goku works around it by firing a Kamehameha into the ground to boost him into the air, allowing him to ram into him with his one good fist. Amusingly, his son Gohan would perform an actual one-handed Kamehameha against Cell!
- The last use of this technique is in the finals of the 23rd Tenkaichi Budokai where Goku uses his feet to launch himself into the air to Piccolo Jr., leaving his hands free to attack his opponent.note
- In an early After War Gundam X episode, Garrod uses the Satellite Cannon to propel himself and Jamil away from a disused nuclear power station that was Going Critical.
- In Space Battleship Yamato 2199, the ship escapes an enemy warp gate hub by firing the Wave Motion Gun and deactivating the gravity brake to shoot through their exit gate while destroying the hub's power source and a big piece of the enemy fleet gathered there.
- They also did it in Yamato 2 (the Comet Empire series) when the Argo was trapped in an electromagnetic tunnel and the only way out was deactivating the recoil systems and shooting the ship "out like a pea".
- In A Certain Magical Index and A Certain Scientific Railgun, Shizuri Mugino can cushion her fall or launch herself through the air by firing her Meltdowner downwards.
- In episode 4 of the Nobunagun anime, Shio uses the recoil from Nobunaga's Three-Line Volley to help steer herself and Jack The Ripper while the two are free-falling through a hurricane, with the latter attempting to destroy the eggs from the Evolutionary Invasion Object they just killed before they make landfall on the coast of Florida and hatch in the storm's aftermath.
- In Mobile Suit Gundam MS IGLOO, during the Hidolfr's battle, it gets a Zaku arm lodged in its tracks, immobilizing it. Since it needs to turn around in a hurry, the pilot fires its 300mm Cannon, the recoil of which lifts the tank halfway off the ground and allows it to use its other set of tracks to turn around before falling back down.
- Natsu in Fairy Tail can launch himself off the ground with his flame. After a second Time Skip during which he spent an entire year training, he's powerful enough to propel himself into the air while resisting Bluenote Stinger's gravity magic.
- In the Pokémon episode "Johto Photo Finish", Ash uses his Charizard to battle Harrison's Blaziken. At one point, Charizard uses its signature Seismic Toss to piledrive Blaziken into the ground, seemingly ending the battle... until Blaziken gets back up! Misty asks how Blaziken survived it, and Brock explains that just before they hit the ground, Blaziken used Flamethrower as a cushion against Charizard's Seismic Toss. Blaziken would go on to win the match for Harrison.
- Episode 4 of Space Patrol Luluco has a variation. The character's gun forms acted as the rockets for a space shuttle, but rather than shooting downwards, they each shot upwards and fell back to earth. Luluco also does a more traditional example in episode 8 to get to the top of a tower.
- In Lost Universe, this happens with a Laser Blade of all things. Millie takes Kane's Psycho Blade and tries to use it herself, but ends up going overboard and propelling herself into a wall. Kain later pulls the move against the assassin sent to kill him to catch her off guard when his normal attacks don't work.
- The French series Dungeon: The Early Years has Marvin obtain an Iron Man-esque suit of armor that has nitroglycerine-based cannons mounted in the arms. He uses them to fly around.
- In The Transformers: Robots in Disguise, Galvatron flies by firing his Arm Cannon behind him. Unlike many versions of the franchise, most Decepticons can't fly in robot mode unless they also have a flying alt-mode.
- In Bookhunter, Agent Bay uses the exaggerated recoil from a shotgun to propel himself across the room, landing behind a perp he's trying to take down.
- Mkbewe in Kapitan Bomba, after he's turned into a cyborg, gains the flying ability by shooting his laser towards ground.
- In The Bridge, Mariner Chibi Moon finds she can launch herself through the air using the magical emulations of her sensei, Godzilla Junior's, shockwaves and energy beam attacks. Godzilla Junior remembers this, when he's falling from orbit and does so himself to stop his fall and fly back into the fray; Godzilla vs. Hedorah style.
- In My Huntsman Academia, Izuku tries to follow Yang's example and uses Emerald Gust to try to slow his descent at Initiation. He ends up not using it again, because the amount of propulsion he got didn't justify spending a lengthy amount of time reloading his pump-action shotgun gauntlets and boots.
- In The A-Team, after losing two of the three parachutes in a falling tank from Attack Drone fire, the A-Team uses the main gun to steer the plummeting vehicle towards a (slightly) softer landing in a lake.
Drone pilot: Are they trying to shoot down that other drone?
Charissa: No... They're trying to fly that tank.
- The infamous scene in Godzilla vs. Hedorah where Godzilla uses his atomic breath to fly.
- Pacific Rim: Uprising: Jake and Amara use the plasma cannon to steer a free-falling Gipsy Avenger onto the Mega-Kaiju as a downplayed Colony Drop.
- Used by Cherry Darling in Planet Terror; by projecting a grenade launcher straight down, she is able to propel herself over a wall (and somehow land unharmed).
- Wax uses a large-caliber gun to push himself sideways when he's flying around at significantly reduced weight in The Alloy of Law.
- In Halo: The Cole Protocol Lieutenant Jacob Keyes orders his men to use this technique to escape from a Insurrectionist freighter. Justified in that they're all in space so their guns would act like backup thrusters.
- In King David's Spaceship, the spaceship in question uses a purpose-built autocannon for propulsion, similar to a scaled-down Orion Drive.
- Exploited inverted in Star Carrier: Earth Strike. Marissa Allyn uses the recoil from her Starhawk's RFK-90 kinetic kill cannon to increase her time on target when attacking the Turusch flagship Radiant Severing.
- In Charlie and the Great Glass Elevator, exploiting this is how Wonka, Mr. and Mrs. Bucket, Charlie, and Grandpa Joe maneuver around the GGE while it is in space. They do so by blowing.
'My dear boy,' said Mr Wonka. 'You can't swim in this stuff. It isn't water, you know. It's air and very thin air at that. There's nothing to push against. So you have to use jet propulsion. Watch me. First, you take a deep breath, then you make a small round hole with your mouth and you blow as hard as you can. If you blow downward, you jet-propel yourself up. If you blow to the left, you shoot off to the right and so on. You manoeuvre yourself like a spacecraft, but using your mouth as a booster rocket.'
- In Cibola Burn, the pilot Alex uses a keel-mounted rail gun for orbital station-keeping, because it's more efficient than diverting power to the engines.
- Farscape. John Crichton does this with a pulse rifle when cast adrift in space, even though the recoil of an energy weapon should be miniscule.
- On Doctor Who, the Fifth Doctor does this with a cricket ball. Since he bounces it off a space ship, he gets the added inertia twice. (Once when he throws it, once when he catches it.)
- The "Recoil Rocket" perk from GURPS: Gun Fu works this way.
- From Warhammer 40,000, the Orks believe that a proper gun should be big, loud, and gives a satisfying bang when it goes off (of course, being heavy and sturdy enough to use it to bash with is fundamental). Most of them modify their guns to produce quite a kick, impractical as it makes it, even for them; and even have looted tanks modified for bigger booms and more recoil.
- Ruby and Yang's combat styles involve using the recoil of their sniper rifle/scythe and gauntlet/shotgun Swiss Army Weapons, respectively, with deadly efficiency. Primarily, they use this to blow themselves across the battlefield; Ruby also does this to pull her weapon right through her enemies.
- Also used by Pyrrha (her spear/rifle), Nora (her hammer/grenade launcher), Blake (her gun/whip), and Mercury (his boot/guns) in similar fashions. If a fight scene in RWBY doesn't involve at least one recoil boost, then it was probably a short one.
- Death Battle:
- Gamera attempted a Meteor Move on Godzilla. Godzilla fired his atomic breath downward, which cushioned his fall enough that he wasn't that hurt when he landed.
- Naturally, used by the aforementioned Yang in her clash with Tifa Lockhart. Used more creatively as a finishing move at the end of the fight: Yang grabs Tifa's head from opposing sides and then fires both of her gauntlets at once, and the recoil pulls Yang's arms away, violently jerking Tifa's head all the way round and killing her.
- Bob and George have touch-and-dies character Ran equipped with a crazy-strong gun that can lift him off his feet with the recoil. And Ran is made of VERY heavy, cheap parts.
- From Darths & Droids, as the characters are trying to survive a spaceship crash and looking for something Crazy Enough to Work:
Anakin: I pull back on the control stick. We need to come in level.
R2-D2: Not crazy enough!
Obi-Wan: Aim for that runway. It could be long enough.
R2-D2: Not crazy enough!
Anakin: I raise the flaps to increase our drag.
R2-D2: Not crazy enough!
Obi-Wan: I dump the excess fuel!
R2-D2: Not crazy enough!
Anakin: No! Wait until just before we hit the ground. I'll fire all our missiles downwards at point blank range. The explosion will cushion our landing.
R2-D2: Too crazy!
Anakin: Trust me.
- A short storyline in Turn Signals on a Land Raider has Kren and Frep flying an Assault Cannon and steering with the recoil. They challenge an Eldar hovertank, but lose horribly.
- In 8-Bit Theater, Black Mage creates a rocket boat by standing on an ordinary boat and firing a "Boat-doken" backwards.
- One of Sergeant Schlock's signature moves in Schlock Mercenary is to disable the recoil compensation on his plasma guns, allowing him to fly as he pleases. He first discovered this ability after being pitched off of a skyscraper. (The narrator comments, "what's the difference between a plasma cannon and a plasma rocket", then cuts to Schlock reading the user's manual to find the answer.)
- Spacetrawler: Pierrot pulls this off unintentionally, here: he fires a ballistic handgun while spacewalking, and the recoil sends him flying. In the comments below, the author admits that he exaggerated the recoil for the sake of comedy.
- The concept is scientifically examined in this What If?, which provides both the page image and the page quote. It turns out that an AK-47 has a higher thrust-to-weight ratio than the Saturn V rocket, though bringing more than 250 rounds of ammunition or having it lift anything heavier than a squirrel would not work; a GAU-8 Avenger would make a respectable rocket engine (breaking the interstate speed limit in three seconds); and a GSh-6-30 would be even better, though would likely kill the user or break the vehicle apart in the process.
- Worm: Damsel of Distress (as well as her clone Swansong in Ward) can fire "annihilation blasts" whose energy obliterates anything it touches, save for her own body. She can also use the recoil from these blasts to propel herself through the air.
- In the short movie "C: 299792 kilometers per second", spaceship Kestros IV escapes Sol by inverting the firing path of its RKV launcher and then, after jettisoning the main engine block to prevent kinetic explosion too close to the rest of the ship, firing it at full power. The final escape velocity was planned to be 0.0286c.
- One episode of Dastardly and Muttley in Their Flying Machines has Dirk's plane nosediving to the ground. He manages to brake his descent by firing his plane's machine gun continuously.
- A similar gag once happened in Wacky Races where the Anthill Mob fired machine guns for a speed boost.
- Azula and her father Ozai in Avatar: The Last Airbender are capable of Not Quite Flight using firebending to propel themselves. (Although, Ozai is only shown doing this during Sozin's Comet).
- The grandson of Zuko from ATLA, Iroh, is shown to be quite skilled at this in The Legend of Korra, jumping between aircraft in a mid-air battle. However, given that he isn't comet-enhanced like Ozai was, he can't maintain it continuously and instead commandeers aircraft whenever possible. Mako and Korra also use the ability briefly to do a wall-run during Amon's rally, and in the second season they use the boost to get a plane in the airway when the runway was too short.
- Yosemite Sam of the Looney Tunes has been known to propel himself into the air by firing both his revolvers downwards.
- The BOTS Master has the BOYZZ crashing towards the moon at one point with failing retro-rockets, so they open up their cockpits and all open fire at the ground to slow themselves down. Runs into the same energy weapons = little recoil issue that previous ones do. However, they just needed to slow down a little, and they were firing a lot of guns.
- In one of "The World of Commander McBragg" shorts on Tennessee Tuxedo and His Tales, McBragg uses the recoil on his high-powered rifle (which was responsible for getting him into this mess in the first place) to propel himself out of the pit he had fallen into.
- In The Simpsons episode "Homer Goes to Prep School", after stealing supplies from doomsday preppers with the intent of sharing them with the citizens of an EMP-stricken Springfield, Homer is chased by the preppers in non-gas-powered vehicles. Superintendent Chalmers in a car powered by a wood-burning stove, Herman in a horse-drawn car, and Lindsay Naegle in an office chair firing a machine gun in the opposite direction.
- This would work with hand-held weapons in a microgravity environment, and is essentially a small-scale version of Explosion Propulsion. Unless specially modified for vacuum, however, many gun cartridges wouldn't work in space.note And trying this on a space station would be... inadvisable.
- Experiments have been conducted on the feasibility of using railguns or mass drivers as spaceship propulsion, which essentially would make your entire spaceship a backwards-firing gun. The Orion Drive is similar in that it uses nuclear bombs to provide thrust. Obviously, it works best in a vacuum away from any livable planets.
- In an inversion, the recoil from a GAU-8 Avenger on the A-10 Thunderbolt is severe enough to give the plane a noticeable drop in speed with each burst, though never quite enough to actually stall it.note This is actually helpful, since at slower speeds it's easier to aim (and the A-10's not about to outrun anything at the best of times anyway).
- Very noticeable with First World War biplane aircraft where forward-mounted MGs could exert a noticeable braking effect on planes travelling no faster than 80 - 100mph. Second world war planes modified to carry heavy cannon could also be slowed at the moment of firing: the JU-87 Stuka modified to carry a pair of 37mm anti-tank gun under both wings for instance, or the HS-129B-3 carrying a 75mm cannon under the fuselage.
- This is basically how the proposed space fountain works. A variant on the Space Elevator, space fountains stay aloft not by tensile strength in a cable (as in regular space elevators), but by constantly shooting pellets down towards Earth (while replacement pellets are constantly shot back up). While this design lets it stay in orbit in far lower altitudes than a normal space elevator, it needs a constant, extremely high supply of energy to power the shots, or else it'll fall.
- Trap-jaw ants have spring-loaded mandibles powerful enough that they can launch themselves away from predators by biting at the ground.