Created By: JonnyB on November 7, 2012 Last Edited By: eroock on August 11, 2016

Giant Spinning Duct Fan

In every air duct, there will be one.

Name Space:
Main
Page Type:
Trope
Brandon: You're deep in the underbelly of the Omega 13! Oh, it must be spectacular.
Gwen: It doesn't look like much to me. There's just these few walls and this dumb spinning fan that's in every single...
- Galaxy Quest

In any Air-Vent Passageway or air shaft, there will inevitably be one: A giant spinning fan. It usually seems to serve no purpose, other than to convey to the viewer that there is air flow there. Sometimes it will be spinning slowly, casting ominous shadows; often it will be a Deadly Rotary Fan of Doom if a character can come into contact with it. But it will always be there, somewhere.


Examples:

Film
  • The page quote comes from Galaxy Quest. At the bottom of the Omega 13 shaft is the ubiquitous dumb spinning fan - which is lampshaded.
  • At the top of the fizzy lifting drink shaft in Willy Wonka and the Chocolate Factory.
  • There's one in the air duct in The Fifth Element.
  • In Aliens, an giant duct van casts an eery shadow in the scene where they find Newt in the duct system.
  • Blade Runner arguably made the "big fan+steam+light shining through" a staple of Cyberpunk-Noirish media.
  • Total Recall (1990). These can be found in the Martian colony's walls, where they pull in fresh air from other areas. At one point the Big Bad Cohaagen turns them off in one area in an attempt to suffocate the mutants who support Kuato.
  • Seen in Iron Sky.
  • The hitwoman of Columbiana is not only small enough fit in an air duct but through the blades of the fans in them.(Which may or may not break one's suspension of disbelief that one so tiny can last in fights with those who...are not)

Live-Action TV
  • In the Doctor Who episode "The End of The World", the Doctor having to get to a switch blocked by gigantic spinning fans in a giant air conditioner area.
  • Alias: One episode ended on a Cliffhanger with Sydney struggling not to get pulled upwards through an air vent into a huge fan.

Video Games
  • They're in almost every air duct in Half-Life.
    • And in an air duct of Nova Prospekt in Half-Life 2.
  • All over in the Underworld regions of Silent Hill. You're given the idea there must be huge air shafts behind them, but they're behind grates and inaccessible.
  • There's one in the air vent of Gehn's study in Riven. Weirdly, the protagonist is able to squeeze into the tube once it's been turned off, even though the gap between the blades is a few inches at most.
  • Some tunnels in the Metroid Prime series contain these. A few can be destroyed.
  • Completely averted in Metal Gear Solid. Crawling around air ducts is a necessity, and there's not a single fan to be found in any of them.
  • Deus Ex and Deus Ex: Human Revolution have duct fans as dead ends.
  • A common element in the sewers levels of Crash Bandicoot 2. A few would even be so fast that one has to destroy it by ricocheting a nearby enemy (said enemy respawns after a few seconds for more ammo).
  • Duke Nukem 3D starts out on a rooftop, with no way down except for an air duct that runs along the side of the building. Of course, Duke must shoot or kick the useless fan out of his way first.

Western Animation
  • In The Secret Of NIMH, as the mice and rats are escaping NIMH through an air vent a fan blows most of the mice to their deaths because they were lighter.
  • In the third Futurama movie the crew sneaked into Mom's Alaskan base through the vents, the outer intakes had giant, red-hot spinning fans... one of which grazed Fry's butt.

Real Life
  • Obviously, air ducts do need to have a fan in them somewhere, but nearly all modern HVAC systems use centrifugal fans instead of the "axial" fans that appear in fiction. Centrifugal fans have lots of real-world engineering advantages (cheaper, quieter, more reliable, easier to scale up) but wouldn't look nearly as interesting from inside the duct, which is what matters in fiction.
    • And that "somewhere" is usually special rooms that also contain air filters, AC, heat exchangers, dampers etc. These things is usually fitted into units that make it impossible to see a fan at all if one crawls around in the ducts. (Filters on the sucking side, dampers on the blowing and the other stuff somewhere in the middle.)
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Community Feedback Replies: 35
  • November 7, 2012
    DRCEQ
    Completely averted in Metal Gear Solid. The game where crawling around air ducts is a necessity, and not a singe fan to be found in any of them.
  • November 7, 2012
    triassicranger
    I don't recall if it was an air duct, but the Doctor Who episode "The End of The World" features the Doctor having to get to a switch blocked by gigantic spinning fans.
  • November 7, 2012
    JonnyB
    ^ Pretty sure that wasn't an air duct. That one would just qualify as a Deadly Rotary Fan.
  • November 7, 2012
    Generality
    There's one in the air vent of Gehn's study in Riven. Weirdly, the protagonist is able to squeeze into the tube once it's been turned off, even though the gap between the blades is a few inches at most.
  • November 7, 2012
    foxley
    Why is it a 'Dumb Spinning Fan'? What's dumb about it?
  • November 8, 2012
    JonnyB
    ^ 1) "Dumb" comes from the movie quote, 2) The fan seems to serve little purpose, other than to give the impression to the viewer that there's air movement (or menace, in the case of a DRF).
  • November 8, 2012
    Arivne
    Film
    • Total Recall 1990. These can be found in the Martian colony's walls, where they pull in fresh air from other areas. At one point the Big Bad Cohaagen turns them off in one area in an attempt to suffocate the mutants who support Kuato.
  • November 8, 2012
    elwoz
    In Real Life, obviously air ducts do need to have a fan in them somewhere, but nearly all modern HVAC systems use centrifugal fans instead of the "axial" fans that appear in fiction. Centrifugal fans have lots of real-world engineering advantages (cheaper, quieter, more reliable, easier to scale up) but wouldn't look nearly as interesting from inside the duct, which is what matters in fiction.
  • November 8, 2012
    m8e
    ^And that somewhere is usually special rooms that also contain air filters, AC, heat exchangers, dampers etc. These things is usually fitted into units that make it impossible to see a fan at all if one crawls around in the ducts. (Filters on the sucking side, dampers on the blowing and the other stuff somewhere in the middle.)

    At least in buildings that's big enough to to have Air Vent Passageway.
  • November 8, 2012
    Surenity
    In The Secret Of NIMH, as the mice and rats are escaping NIMH through an air vent a fan blows most of the mice to their deaths because they were lighter.
  • November 8, 2012
    shimaspawn
    Dumb in the title serves only to

    1) Encourage bashing of the trope.

    2) Confuse the reader as to what the trope is about. Spinning Duct Fan would be clearer.
  • November 9, 2012
    Tuckerscreator
    • Some tunnels in the Metroid Prime series contain these. A few can be destroyed.
  • November 9, 2012
    Chernoskill
    • Blade Runner arguably made the "big fan+steam+light shining through" a staple of Cyberpunk-Noirish media.
  • November 11, 2012
    JonnyB
    Considering the name change, although I see the word "dumb" as having the meaning of "having no active use or purpose in and of itself", not as an epithet of stupidity.
  • November 11, 2012
    surgoshan
    The Doctor Who example waaaay up there was in an air conditioning ... thing. It made almost no sense, but it served the same purpose; big ole fan blades the Doctor had to dodge.
  • November 11, 2012
    Stratadrake
    I agree that using "dumb" here is intended to be the same / comparable context as, say, Big Dumb Object ... however, BDO is a pre-established term, while DSF strikes me as trying to shoehorn a new Trope Namer.
  • November 14, 2012
    Nitzy
    Deus Ex and Deus Ex: Human Revolutions has duct fans as deadends
  • November 15, 2012
    JonnyB
    Hats, then.
  • November 15, 2012
    LeeM
    Seen in Iron Sky.
  • November 15, 2012
    KarjamP
    A common element in the sewers levels of Crash Bandicoot 2. A few would even be so fast that one has to destroy it by ricocheting a nearby enemy (said enemy respawns after a few seconds for more ammo).
  • November 15, 2012
    zarpaulus
    • In the third Futurama movie the crew sneaked into Mom's Alaskan base through the vents, the outer intakes had giant, red-hot spinning fans. One of which grazed Fry's butt.
  • November 15, 2012
    Cider
    The Colombiana of Colombiana is not only small enough fit in an air duct but as through the blades of the fans in them.(Which may or may not break one's suspension of disbelief that one so tiny can last in fights with those who...are not)
  • November 20, 2012
    Chernoskill
    Not sure if the trope was tightened to only include large fans in ducts, but as it stands now the Blade Runner example doesn't fit anymore.
  • November 20, 2012
    SharleeD
    • In Beyond the Spirit's Eye, you must stop a giant fan from spinning by sticking the bolt-cutters between its blades. This gets you access to the room beyond and also a large magnet.
  • November 20, 2012
    shimaspawn
    <Mod Hat>

    You have a lot of Zero Context Example entries here and very few of them indicate any sort of narrative purpose that would turn them into a trope. You seem to be in People Sit On Chairs territory especially with the addition of Aversions to the list. There doesn't seem to be anything here.

    This trope will be discarded if meaning is not found.
  • November 21, 2012
    m8e
    We need to remove the Deadly Rotary Fan examples.

    I think we can might have three or more tropes here:

    Fan Obstacle: Like Steam Vent Obstacle but with a fans. One have to stop the fan or time a jump right to get through, find another way, etc. But I don't think this should be limited to games.

    Dumb Fan(really bad name, Superficial Fan?). The fan doesn't really do anything, it just there to change the feel/look of the setting. Making it look more "punk", industrial, "Remember, they are in an insanely huge air duct now" or whatever.

    Fan That Blows(or something like that). Fans that's actually move air, and normaly don't chop people to death. Not any sitting on chairs fan, this fan do stuff like blowing people around/make them fly, kill peope by cooling(or heating) them, suffocate people when it stops, moves/spreads that deadly gas/virus/whatever from one place to another.

    There is of course some overlap, a Deadly Rotary Fan that suck in people(i.e they don't fall in) is also a Fan That Blows(or in this case suck). A Fan Obstacle is often a Deadly Rotary Fan and sometimes it's a Fan That Blows really hard.
  • November 21, 2012
    cubicapocalypse
    Game example: One of the first rooms after you escape has a pair of these on either side. These are your only exits.
  • November 22, 2012
    JonnyB
    ^^ The reason I included those, I'm thinking this is a super-trope.
  • November 22, 2012
    m8e
    ^I don't think it's possible to make a super-trope of this. It just ends up with ZCEs, PSOC and crap. We need the separate tropes(if they are tropes).
  • July 17, 2013
    JonnyB
    Going to work on salvaging this...
  • May 3, 2015
    eroock
    So this one is dead?
  • May 3, 2015
    DAN004
    ^ It was, until somebody revived this.

    If this can be anything other than PSOC, then kindly educate me.
  • May 3, 2015
    eroock
    It cannot be taught, you need to experience it. Watch Blade Runner to grasp the atmospheric impact of gigantic rotating (while non-lethal) fans casting menacing, moving shadows during a Darkened Building Shootout.

    Come to think of it, often this trope and Eerie Flickering Sign cover the same ground.
  • May 3, 2015
    DAN004
    Then call this Eerie Rotary Fan?
  • May 3, 2015
    oneuglybunny
    Video Games
    • Duke Nukem 3 D starts out on a rooftop, with no way down except for an air duct that runs along the side of the building. Of course, Duke must shoot or kick the useless fan out of his way first.
http://tvtropes.org/pmwiki/discussion.php?id=72092bnkd5zy70aohsu20jg4&trope=DiscardedYKTTW