"No Warping" Zone

Faster-Than-Light Travel is often accompanied by certain regions of space where such travel is either impossible or extremely dangerous. Limiting when and where FTL can be used is needed to justify Cool Starships, space battles, or chase scenes.

The most common variant is a region surrounding a massive object as big as a star system or as small as a ship. If Hyperspace Is a Scary Place, the scariest regions might be effective No Warping Zones.

No relation to the Video Game equivalent of Warp Zones. See also Teleport Interdiction.

Film

 * In Star Trek: The Motion Picture, Kirk says that the urgency of their mission means that they have to take the "dangerous" risk of engaging warp drive while still within the solar system. As it turns out, that wasn't the problem. It was the improperly-tuned warp engines, which created an unstable wormhole. Oddly, Trek had never described intra-system warp travel as dangerous before, or since. (Indeed, many episodes of Star Trek: The Original Series ended with the Enterprise leaving orbit around a planet at warp speed.)
 * There was a Deep Space Nine episode where a changeling was about to induce a supernova in Bajor's sun. They get wind of it at the last second, but the only way to stop it is to warp through the system. Dax is aghast, but Kira, what with most of her species' lives on the line, is less restrained.

Literature
""A ship which attempted to translate out of hyper inside a star's hyper limit couldn't. As long as it made the attempt within the outer twenty percent of the hyper limit, all that happened was that it couldn't get into n-space. If it made the attempt any further in than that, however, Bad Things happened. Someone had once described the result as using a pulse cannon to fire soft-boiled eggs at a stone wall to see if they would bounce.""
 * In Vernor Vinge's Zones of Thought universe, FTL travel is impossible in the interior 80% or so of any given galaxy (in particular, including the Earth).
 * In the Foundation and Empire books by Isaac Asimov, hyperspace jumps close to a gravity well such as a star or planet are perfectly possible. It just makes the the calculations necessary so immensely complex that by the time you could make a jump that isn't blind, you generally could have gotten far enough from the gravity well that a much simpler calculation would have been necessary. The same problem exists on the destination side, except doing a Blind Jump is a worse idea in that direction (making a blind jump out of a system is less liable to cause you to reenter normal space inside something than making a blind jump to a system).
 * In Larry Niven's Known Space series, starships can't go FTL near a star, black hole or other massive object or they will be lost forever. Ships thus need to leave a star system using normal engines before engaging their FTL drive, and if they get too close to any massive object while en route, they must drop to normal speeds or simply vanish. This is also implied to be the reason why we believe FTL travel is impossible in Real Life today—we live too close to a star's gravity well, which warps the way physics works, and thus our understanding of what is and isn't possible.
 * Stars, and large planets, in the Honorverse have a "hyperlimit." Ships can't transition to, or from hyperspace inside that limit. Attempting to leave hyperspace inside the hyperlimit is instant death.


 * Hyperspace also has "gravity waves." Before the invention of Warshawski sails, any ship that entered a gravity wave would be torn apart. After the invention of Warshawski sails, gravity waves became the fastest way to get around the universe. But the sails end up being a large liability in a hyperspace fight.
 * In the Halo novels, you can't enter Slipspace while near large gravitational fields, like planets. Unless
 * In Neal Asher's Polity books, USERS (spinning black holes inserted into and back out of Underspace) create wavelike distortions - like throwing a pebble into a pool, repeatedly - that knock ships back into normal space. Used for interdiction and incident containment by Polity Agents and other EC forces.
 * In Peter F. Hamilton's Night's Dawn Trilogy, starships (both conventional and biological) are unable to perform ZTT jumps or Swallow maneuvers within a certain radius of a gravitational field since local space is too warped to allow safe transmission. This radius is much smaller for the more sophisticated bitek Voidhawks, however, and Lagrange points (spaces where the gravitational pull of a planet is cancelled out by that of another celestial body such as a moon or star) theoretically allow FTL travel within a gravity well.
 * Until
 * In Vladimir Vasilyev's No One but Us, three alien armadas are heading towards Earth and two other major human worlds. As part of defending them, powerful Nonlinear Field Generators are engaged, preventing the enemy from warping in, leaving only a tiny (by comparison) window, allowing them to "funnel" the enemy into a predictable position. This field is large enough to encompass the entire system.
 * In Ryk Spoor's Grand Central Arena, Sandrisson Drives, even when inactive, interfere with each other, which wouldn't be an example of "No Warping" Zone except that drives jump from the volume of a planetary system to the artificial "Spheres" which are much smaller. A smallish number of ships occupying a Sphere can entirely prevent jumping from anywhere in the planetary system.
 * Murray Leinster's short story "First Contact" was published in the 1940s, when many astronomers believed that outer space was a perfect vacuum. The human-piloted starship in that story could only travel faster-than-light in a total vacuum—even the slightest wisp of atmosphere or nebula would be enough to prevent it.
 * In the Star Wars Expanded Universe, it's stated that you can't use a FTL drive while within the 'mass shadow' of a planet or star. Entering a mass shadow while traveling FTL will pull you out of hyperspace, which in the case of a star, is a very bad thing. There are also ships, called interdictors, capable of generating artificial mass shadows that can yank a ship right out of hyperspace no matter how fast it's traveling. They were difficult to maneuver while performing this function and attracted space debris.
 * An upside for interdictors was found by Grand Admiral Thrawn, that Magnificent Bastard for all seasons. Normally, interdictors are used to prevent enemy ships from escaping via hyperspace. But it wasn't long before Thrawn began using them in more traditional No Warping Zones to snag his own ships. By maneuvering the interdictors just so, he could simply launch an entire fleet towards them and have them drop out of hyperspace, even in crowded conditions, with pinpoint accuracy.
 * Much of the plot of Knights of the Old Republic 2 is driven by the fact that the Exile used a Mass Shadow Generator, presumably based on the same technology. It destroyed a whole Mandalorian battlefleet... and a planet.
 * In Sergey Lukyanenko's The Stars Are Cold Toys, the human jumper does not appear to have a "No Warping" Zone. However, they are never activated inside a planet's atmosphere. This is because they transport a large sphere around them. Suddenly removing a chunk of an atmosphere has consequences for the planet below.
 * Similarly, in Angel Station by Walter Jon Williams, ships entering or exiting a jump must do so far away from planets, as the process releases deadly radiation. The protagonists are forced to jump fairly close to an inhabited moon, realizing they're committing a heinous crime.

Live-Action TV

 * Star Trek: Voyager introduced the Omega Directive, which instructed that Omega Molecules be destroyed upon discovery- and even overrode the Prime Directive. Why? Because Omega Molecules had nasty habit of exploding—and when they did, they created a huge void where FTL travel and communications didn't work, potentially crippling to The Federation and every other spacefaring race within a few thousand light years.
 * An episode of Star Trek: The Next Generation centered around the dangers of warp travel in high traffic areas leading to the erosion of the fabric of space-time, causing catastrophic Negative Space Wedgies and, potentially, worse. As a result, the Federation places a Warp 5 speed limit on their ships except in cases of emergency, which the Klingon Empire agrees to (other factions aren't accounted for).
 * In Babylon 5, there are places in hyperspace that aren't safe.
 * There does not, however, appear to be any limits on where a spacecraft equipped with Jump Engines can enter or leave hyperspace besides the problem of being able to do it precise enough or there's already a jump gate. Jump gates explode if a point is opened up inside of them, while opening a jump point in a gas giant has problems with explosions within the gas. For a more normal planet, the key for jumping in is having accurate enough readings to not accidentally open a jump point inside the planet.
 * Averted in the reimagining of Battlestar Galactica, at least in the traditional "can't warp near a planet" way. In one episode, as part of a sneak attack, the Galactica jumps into the atmosphere of a planet, falls like a stone for a while while launching its fighters, and jumps back out when sufficiently close to the planet that it is identifiable from the surface.
 * At the same time, played straight in one of the season 4 episodes: when a Raptor jumps barely a stone's throw from the Galactica's hull, the gravitational shockwave tears out a good chunk of the hull and catastrophically damages the Galactica's already strained superstructure. So it's not like "you can't jump next to other ships", it's more "you can jump but you're a safety hazard for anyone nearby".
 * It's also shown that when a ship jumps, anything not solidly fixed down will be drawn to the point where it was. When Galactica jumps in New Caprica's atmosphere at the start of Season 3 it causes a massive upward wind surge with accompanying sonic boom, and when the Pegasus jumps from the burning Scorpia shipyards in "Razor", the flames and a lot of debris get pulled into the ship's former location. This would mean jumping would be safest when there's nothing larger than a grain of dust is in your immediate vicinity.
 * Farscape also uses the "hazardous to surroundings, not the ship" issue in regards to the Starburst transport used by the biomechanical Leviathan ships. Played straight if the ship tries to Starburst inside the hanger of another ship or other confined space; the contained energy causes the destruction of both ships.

MMORPGs

 * EVE Online offers several possibilities to drop a "No Warping" Zone on your enemies, or where you expect your enemies to arrive.

Tabletop Games

 * BattleTech's Kearny-Fuchida drives don't take well to gravity. At the same time, recharging the drive via solar sail obviously requires the ship to come out of jump reasonably close to a star to collect energy, and most JumpShips aren't capable of any great sublight acceleration. This results in commercial traffic mostly using a given system's zenith and nadir 'jump points' several AU away from its star and safely above or below most of the clutter in its orbital plane; if actual recharging stations happen to exist in-system, this is where they will be positioned as well. It's possible to jump closer to or from a star by judicious use of Lagrange points (where the star's gravitic pull and that of another celestial body just about cancel out), but since the smaller bodies obviously keep moving around, this requires highly accurate and up-to-date navigational charts and makes for riskier jumps even then.
 * In Traveller, a starship using its jump drive too close to a planetary body or star (within 100 diameters) has an increased chance of misjump.
 * In Spelljammer ships travel in straight line at the spelljamming speed (10^8 miles/day) but drops to the "tactical speed" if they need to maneuver or something big enough (10 space tons for standard engines) is close enough.
 * A common tactic to prevent a Hyperspeed Escape is to launch large amounts of chaff in the vicinity of your enemies. A common tactic to deal with pursuers is the same: the evader crawls at the tactical speed one locking radius from a jettisoned mass, but the pursuer must either slow down for twice this distance or try to circumvent it and risk going off the course; if the evader slows down again and steers while the pursuer is still locked and can't catch up, it probably got away.
 * In GURPS: Banestorm the titular banestorms have screwed up the local laws of magic so badly that teleportation takes a penalty of -25. Not strictly impossible, but in GURPS a skill level of 20 is extraordinary.
 * In the Champions super-hero Tabletop RPG, characters or vehicles can purchase FTL Travel as a Power for only 10 Character Points. They are prohibited from using it in an atmosphere. (Curiously, there's no restriction against using FTL Travel while on the surface of an airless world. You could theoretically spend a few points on FTL Travel, a minimal amount of Flight, and enough Life Support to survive until you fly out of the atmosphere, then engage your FTL Travel and destroy the moon by ramming into it.)
 * Similarly, the Villains and Vigilantes Flight power permits FTL if one's atmospheric flight speed is at least Mach 1, but only outside of atmosphere.
 * In Warhammer40000 Tyranid fleets have the effect of making travel through the warp impossible to or from their location. This is naturally bad news for whatever planet they're approaching, unable to evacuate or receive timely reinforcements.

Video Games

 * As noted on Hyperspeed Escape: Escape Velocity doesn't allow you to enter hyperspace too close to the center of an inhabited system.
 * Elite, possibly the Trope Codifier of "mass-locked" warp drives.
 * The video game Solar Winds displays "Can't hyperjump - Danger near" if you try to go FTL while there's another object on screen (enemies, planets, asteroids).
 * In the computer game Sins of a Solar Empire, ships are unable to conduct "phase jumps" within a gravity well of a stellar object, including stars, planets, asteroids, etc. There are exceptions to this rule, mostly for the Vasari race, whose phase jumping technology is much more advanced than human (either faction).
 * Master of Orion 2 has Warp Dissipator (prevents enemy ships from Hyperspeed Escape in the tactical combat map) and Warp Interdictor (slows down all enemy ships traveling to the system with an Interdictor equipped).
 * Freelancer has no interdicted space, but it does feature Cruise Disruptor missiles that can mess with the target's high-speed cruise engines.
 * These are particularly frustrating if you're running from a group of enemies since all weapons are locked down by engaging the cruise engines. Which would seem to mean that the Counter Measures are also disabled. They aren't, but it's not mentioned anywhere.
 * Sword of the Stars: While human and Zuul ships need to make for a node to escape, the other races have to make a seemingly arbitrary distance from enemy ships before they can retreat.
 * In the Homeworld campaign, it is extremely dangerous for a ship to travel in hyperspace through a massive object in space, such as a planet or a star, or even a large asteroid. As such, a ship is always kicked out of hyperspace whenever such an object is detected ahead in order to make course corrections. This is sometimes used to trap ships, if the original course of the target ship is known. For example, the Taiidani set several traps for the Kushan this way. One involves placing a large asteroid directly on the Kushan mothership's path, attaching drives to it, and sending it towards the dropped-out mothership.
 * In the first Noah mission in Nexus the Jupiter Incident, the player's convoy is intercepted during its IP (interplanetary) jump by the Raptors, who have somehow obtained the technology to do this. This is the only time this happens in the game, though. Additionally, the Vardrag have the technology to lock down wormholes, preventing ships from getting in or out.

Web Comics

 * Teraport Area Denial in Schlock Mercenary work by detecting and disrupting the wormholes used by the Teraport. Not really a pure No Warping Zone, since you can program your TAD to check for what are essentially "passwords" encoded in the wormholes themselves to let certain teraports through. They can also be circumvented, by using a teraport cage to block the sensors. Or just bulled through by using truly ridiculous amounts of power.

Web Original

 * The space in between the Jump Gates in Nexus Gate counts as a huge "No Warping" Zone.
 * Fenspace: Played straight and inverted. Ships can't go FTL when they're too close to a star - how close is "too close" varies by the star, with larger, more energetic stars surrounded by larger areas where FTL doesn't work, the radius of which is measured in Astronomical Units. Conversely, when ships use handwavium engines outside "the limit," they automatically go FTL.