History Main / SilentRunningMode

* Possible, but rarely used in ''VideoGame/{{Mechwarrior}} 4''. Mechs could shut down completely to remove themselves from electronic detection. This wouldn't make you invisible, but a good observation point could let you set up an ambush.

** Later, the [[spoiler:Mesan Alignment]] develops ships that use a new type of propulsion that is completely invisible to gravitic sensors, the so-called Spider drive (it uses incredibly powerful {{Tractor Beam}}s to pull itself towards the [[SubspaceOrHyperspace hyperspace]] wall (which is everywhere). These new types of ships are, essentially, this 'verse's equivalent of submarines. Slow and fragile (no impeller wedges or [[DeflectorShield sidewalls]]), but hidden and capable of dealing great destruction without advance warning.

* The ''Series/StarTrekTheOriginalSeries'' episode "Balance of Terror." A virtual [[RecycledInSpace remake]] of the 1957 film ''TheEnemyBelow''.

** However, while a diesel sub can be quieter, it has to run at no deeper than periscope depth to run the diesel and recharge the battery, and can only run at depth for a limited time, until it becomes necessary to go back to periscope depth to charge the battery again. Nuclear submarines can operate submerged until the crew runs out of food, so despite being noisier than diesels, they have replaced diesels in the most advanced navies of the world.

** Ditto for ''StarTrekBridgeCommander''.

* In ''Film/BatmanBegins'', the Batmobile has a stealth mode. Despite being right in the middle of several cop cars on a two-lane highway, somehow nobody notices the thing. To be fair, it was night and most of the streetlights were out, but still ...

** In the pilot episode, the characters had to do this against the Alliance to keep from getting boarded and searched as they do some illegal salvage -- unfortunately for our heroes, they are still detected as they're taking off but throw out a decoy to escape.
** When rescuing the Captain from [[BigBad Niska's]] space station, Wash has ''Serenity'' going unpowered so Niska's men won't see them coming. Given this means no maneuvering, Zoe compares it to throwing a dart from thousands of miles away.

** In the pilot episode, the characters had to do this against both the Alliance and the Reavers, the former to keep from getting boarded and searched, and the latter to keep from getting raped to death, their flesh eaten and their skins sewn to the Reavers' clothing. And if they're very, very lucky, it'll happen in that order.
** Likewise when rescuing the Captain from [[BigBad Niska's]] space station.

** Interestingly, diesel subs are in general much quieter than nuclear boats. That's because on the nuclear sub the reactor cooling must be on ''all the time'', lest it suffers a meltdown, and cooling pumps tend to be quite loud. Also, being large and heavy contraptions, they are exceedingly difficult to completely isolate from the hull. Even with the newest rector designs, where the cooling could be driven by natural convection on low power settings, the rush of coolant itself through the tubes creates a fairly loud hum, and the reactor is even ''more'' difficult to completely soundproof. Diesel subs, on the contrary, can turn off virtually ''all'' their systems in silent mode, the batteries or fuel elements are intrinsically silent, and electric motors on the low power produce virtually no noise. So the loudest sounds on a diesel sub would probably be from the crew moving around.

* In the ''VideoGame/{{Fallout}}'' series of games, the Silent Running perk takes the phrase much more literally.

* ''Film/DasBoot'', TruthInTelevision with the portrayal of [[http://en.wikipedia.org/wiki/Silent_running_(submarine) true silent running]] in submarine warfare.

* ''Film/DasBoot''

** Interestingly, diesel subs are in general much quieter than nuclear boats. That's because on the nuclear sub the reactor cooling must be on ''all the time'', lest it suffers a meltdown, and cooling pumps tend to be quite loud. Also, being large and heavy contraptions, they are exceedingly difficult to completely isolate from the hull. Even with the newest rector designs, where the cooling could be driven by natural convection on low power settings, the rush of coolant itself through the tubes creates a fairly loud hum, and the reactor is even ''more'' difficult to completely soundproof. Diesel subs, on the contrary, can turn off virtually ''all'' their systems in silent mode, the batteries or fuel elements are intrinsically silent, and electric motors on the low power produce virtually no noise. So the loudest sounds on a diesel sub would probably be from the crew moving around.
*** On the other hand, nuclear subs can run in silent mode ''forever'' (or at least for the length of their tour), while diesel boats are limited by battery life.

* In the Sixties the CIA realised they needed a stealth helicopter for infiltrating countries like North Korea. Although realising a completely silent helicopter was impractical, they took a standard Huey and worked on reducing the noise signature of each component -- modifications included replacing analogue components with early electronics and adding an extra rotorblade. Eventually they came up with an aircraft that when flown at a particular speed, along with nape-of-the-earth flying, was unlikely to be detected unless you were specifically listening for it.

* In movie version of ''Film/TheHuntForRedOctober'', they switch on the silent propulsion system and the crew start singing the Soviet National Anthem. One of the crew worries that they'll be heard. Ramius says to let them sing.
-->'''Jonesy''' (on the USS Dallas): The Russian disappeared. One minute he was steady 4000 yards off the bow and....then he was gone. And for a second, I thought I heard.....\\
'''Capt. Mancuso''': Heard...what?\\

* Han's whole Cling-to-the-star-destroyer-and-drift-away thing in ''Film/TheEmpireStrikesBack'' counts, and if not, several times in the ExpandedUniverse (Thrawn trilogy?)

* ''[[Film/StarTrekIITheWrathOfKhan The Wrath of Khan]]'' used the nebula as a variant. It worked by having the radiation emitted by it scrambling the sensors of both ships.

* Yep, TheThrawnTrilogy. Kaarde starts out ''Dark Force Rising'' hiding on an asteroid, watching Myrkr being taken over by the Empire. He only gets caught because Thrawn knows Kaarde is exactly the sort of person to do that, and he only escapes because his Force-sensitive copilot turned everything back on before Thrawn's Interdictor Cruisers finished generating a gravity well trap.

** Specifically, a ship without its wedge powered is invisible to ''gravitic'' sensors; it continues to emit everything else (heat, EM, etc) as normal, and still presents a perfect target for radar and laser systems. However, lots of commanders in the Honorverse don't bother with anything but the gravitics, since gravitics operate at FTL speeds as opposed to light-speed EM-based methods, and it's assumed that any ship attempting aggressive action will have to have its wedge running. Basically, Honor's entire plan hinged on the Peeps being [[TooDumbToLive terminally lazy]] and failing to check their EM sensors. In a later novel, she and Michelle Henke [[LampshadeHanging hung a giant pair of fuzzy dice]] on the tactic for the benefit of a gaggle of hero-worshiping midshipmen, dissecting all of the myriad ways the Peeps could have spotted Honor coming light minutes away and turned her entire fleet into space junk with a single salvo. To quote Henke below:

* In Stephen Baxter's Literature/XeeleeSequence novel ''Exultant'', when an asteroid base goes into steaLTh mode, everyone around the base is quiet. One character points out that there's no reason for this, but another responds that it's purely psychological--being quiet helps everyone feel that they're being stealthy.

* In the ''VideoGame/{{Fallout}}'' series of games there is a perk named silent running that takes the phrase much more literally.

* The ''Normandy'' of ''Franchise/MassEffect'' can briefly use one of these.

* Submarines -- all (or nearly all) are designed to be as silent as possible. However, the film ''The Hunt For Red October'' got some of it right: in a situation where ''immediate'' silence is called for, the order given is "All stop, quick quiet", which means just what it says: The screws are immediately stopped, all communication is done by whisper or hand signs, and where you are standing is where you ''remain'' standing until the order is lifted.
** Interestingly, diesel subs are in general much quieter than nuclear boats. That's because on the nuclear sub the reactor cooling must be on ''all the time'', lest it suffers a meltdown, and cooling pumps tend to be quite loud. Also, being a large and heavy contraptions, they are exceedingly difficult to completely isolate from the hull. Even with the newest rector designs, where the cooling could be driven by the natural convection on the low power settings, the rush of coolant itself through the tubes creates a fairly loud hum, and the reactor is even ''more'' difficult to completely soundproof. Diesel subs, on the contrary, can turn off virtually ''all'' their systems in a silent mode, the batteries or fuel elements are intrinsically silent, and electric motors on the low power produce virtually no noise. So the loudest sounds on a diesel sub would probably be from the crew moving around.

* In the Sixties the CIA realised they needed a stealth helicopter for infiltrating countries like North Korea. Although realising a completely silent helicopter was impractical, they took a standard Huey and worked on reducing the noise signature of each component -- modifications included replacing analogue components with early electronics and adding an extra rotorblade. Eventually they came up with an aircraft that when flown at a particular speed, along with nap-of-the-earth flying, was unlikely to be detected unless you were specifically listening for it.

This trope is almost invariably featured in a SubStory. This trope has also been RecycledInSpace, and many a CoolShip has been called upon to do submarine-style silent running. Often this depends on the unrealistic conviction that [[SpaceIsNoisy there is sound in space]], but it could be denoted as [[StealthInSpace minimizing heat discharge or something similar to prevent detection by sensors]]. Not to be confused with the film ''SilentRunning''.

* ''Film/StarWars'': Han's whole Cling-to-the-star-destroyer-and-drift-away thing in ''The Empire Strikes Back'' counts, and if not, several times in the ExpandedUniverse (Thrawn trilogy?)

* Referenced in ''TheAreasOfMyExpertise'' in a table of short words and abbreviations used by submariners to conserve oxygen. It contains the term "SR" for Silent Running mode. It claims that the term comes from the movie ''SilentRunning'', because it is the sub-mariners' favorite movie.

* In the Sixties the CIA realised they needed a stealth helicopter for infiltrating countries like North Korea. Although realising a completely silent helicopter was impractical, they took a standard Huey and worked on reducing the noise signature of each component -- modifications included replacing analogue components with early electronics and adding an extra rotorblade. Eventually they came up with an aircraft that when flown at a particular speed, along with nap-of-the-earth flying, was unlikely to be detected unless you were specifically listening for it.

** Specifically, a ship without its wedge powered is invisible to ''gravitic'' sensors; it continues to emit everything else (heat, EM, etc) as normal, and still presents a perfect target for radar and laser systems. However, lots of commanders in the Honorverse don't bother with anything but the gravitics, since gravitics operate at FTL speeds as opposed to light-speed EM-based methods, and it's assumed that any ship attempting aggressive action will have to have its wedge running. Basically, Honor's entire plan hinged on the Peeps being [[TooDumbToLive terminally lazy]] and failing to check their EM sensors. In a later novel, she and Michelle Henke [[LampshadeHanging hung a giant pair of fuzzy dice]] on the tactic for the benefit of a gaggle of hero-worshiping midshipmen, dissecting all of the myriad ways the Peeps could have spotted Honor coming light minutes away and turned her entire fleet into space junk with a single salvo. Paraphrased below:
---> '''Michelle Henke:''' Dame Honor's tactic may not have been the single most outrageous, gutsiest, all-or-nothing, do-or-die throw of the dice in the history of the Royal Manticoran Navy. If it wasn't, however, I cannot imagine the action that ''was.''

This trope is almost invariably featured in a SubStory. This trope has also been RecycledINSPACE, and many a CoolShip has been called upon to do submarine-style silent running. Often this depends on the unrealistic conviction that [[SpaceIsNoisy there is sound in space]], but it could be denoted as [[StealthInSpace minimizing heat discharge or something similar to prevent detection by sensors]]. Not to be confused with the film ''SilentRunning''.