As has been established, Space Is an Ocean, and in fiction, naval and maritime terms are often applied to spaceships. Some works, however, take things further, and make their characters go Space Sailing on literal ships IN SPACE! The reason for this? The Rule of Cool, and nothing else.
While, in Real Life, there are proposals for spacecraft with solar sails, this isn't Truth in Television, because they'd still be just spacecraft-with-sails; these are literal boats in space, with all the shape and features that implies.
A subtrope of this is the idea of a space Titanic, an oddly common meme. They are invariably doomed.
- Particularly abundant in the Leijiverse—the anachronistic vehicles are partially what give the shows their charm.
- The anime Nadia: The Secret of Blue Water has none other than Captain Nemo take a Yamato-esque New Nautilus into space to battle a gigantic Atlantaean Flying Saucer named Red Noah. The scene in which the New Nautilus first breaks free of the ground it is imprisoned in is a direct and clear homage to the similar scene in the aforementioned Yamato.
- The anime Odin: Photon Space Sailor Starlight begins with a scene showing lots of futuristic ships plying the spaceways—then brings on its master stroke, a new, better space ship, which is... a wooden sailing ship, complete with decks and rigging and masts and such.
- Space Carrier Blue Noah, AKA Thundersub.
- The Hyper Galaxy Dai-Gurren from Tengen Toppa Gurren Lagann looks much like a HUGE aircraft carrier.
- Had Toei Animation accepted the Toon Makers bid for remaking Sailor Moon (in the infamous "Saban Moon"), instead of DiC's dubbing, Americans would have gotten the Sailor Senshi battling evil by going sailing in space... on space-windsurfers... involving fights with such ships.
- Sol Bianca revolves around a space "submarine", which "dives" and "surfaces" to enter and leave its cloaking effect.
- Crossbone Gundam has the Mother Vanguard, which has broadside beam cannons, a sail that mounts more cannon plus missiles and a high-speed flight system, and a masthead statue of a woman made of gold. This fits with the series' general pirate aesthetic, even if the ship was built before the heroes decided to become Space Pirates.
- Disney's Treasure Planet takes this to the extreme, with a 70/30 blend of 18th century ships combined with technology. It works quite well.
- WALL-E featured the Axiom, a "Starliner" with a design evoking that of a sea-going cruise ship.
- The Fhloston Paradise hotel in The Fifth Element actually does double as both a space and a (hovering-just-above-the-) sea vessel. It looks like a futuristic version of a steam paddle boat. The steam-stacks, however, may be just for show—it is a luxury toy meant for the amusement of rich tourists, after all.
- There is a B-Movie called Message from Space, which has this very thing, but takes it to the extreme. These space sailors are wooden Renaissance-era ships! Oh, and it also includes Humongous Mecha, Planet Looters, Space Pirates, and even a planet with rocket engines! Also has a musket-toting droid.
- In John Ringo and Travis S. Taylor's Into the Looking Glass series, the Human-Adar Alliance's first warp ship is a converted Ohio class ballistic missile submarine. The Adar, upon learning the origin of some of the terms used in the first book of the series (Into The Looking Glass), decide the ship must be named the Alliance Space Ship Vorpal Blade, much to the chagrin of all the humans who know about it.
- In Philip Reeve's Larklight novels, the star ships are nothing more than Victorian sailing vessels with alchemical engines.
- In Leo Frankowski's The Two Space War, Hyperspace is literally two dimensional, and spaceships are sailing ships made of wood infested with an alien fungus.
- A follow-on novella to David Drake's Ranks of Bronze, "Delenda Est Carthago" by Eric Flint features the newly created space navy of Terra, based on stolen technology brought back to 21st century Earth by the survivors of Crassus' Roman legions. Said technology included a warp drive and Deflector Shields which would also work to keep the air in, resulting in humanity's first space fleet consisting of converted submarines, frigates, carriers and battleships, pulled from the waves and into space. The battleship Missouri's part of the action was particularly reminiscent of Uchuu Senkan Yamato. There was, however, one ship included in honour of the returned Romans: a restored Roman galley. The fleet commander was constantly infuriated by the fact the galley's crew were still rowing.
- David Drake also has the Leary/Mundy series where the ships maneuver through a hyperspace with sails.
- Doctor Who has not only the new series Christmas Episode "Voyage of the Damned", one of the aforementioned Space Titanics, but also the 1983 Fifth Doctor serial "Enlightenment", where he and his companions find themselves on board a Sufficiently Advanced Alien Edwardian ship in space, powered via solar sails, which is participating in a race around the planets, along with other such ships from different periods from human history, including a Greek trireme...with rowers.
- Voyage of the Damned could be justified, though, since the aliens purposely made it to look like the Titanic, and many other spaceships in the series look nothing like boats. In other words, it doesn't look like a boat because space is an ocean, it looks like a boat because they wanted it to. The aliens, that is, not just the script writers.
- Star Fleet gives us the Skull, a space going pirate ship complete with sails.
- Gokai Galleon from Kaizoku Sentai Gokaiger, the Space Pirate Super Sentai. It's the Red Ranger's mecha, the central piece to the Combining Mecha, and the team's ride.
- Commander Sisko from Star Trek: Deep Space Nine built a lightship that employed a solar sail for propulsion - Bajorans had even traveled faster than light with these contraptions. At one point in the episode, Sisko even talks about "tacking" with his solar sailing space ship—something impossible to do without a denser medium (like an ocean surface) to sink a keel into.
- One can argue about whether it should be called tacking, but you *can* use solar gravity to sail 'upstream' against the sunlight. (I almost said the solar wind, but those are charged particles, not the photons solar sails use.)
- This was the whole point of the Dungeons & Dragons Spelljammer setting. In this case, it wasn't interstellar space so much as interplanar space. Somewhat justified in that the whole thing is done by magic. Also, sails only provide maneuverability—conventional means of propulsion has the same performance when strapped on almost any object of acceptable size.
- The Eldar of Warhammer 40,000's ships use solar sails for propulsion... which means that if you play as them in the space combat spin-off, Battlefleet Gothic, you'll have to keep track of which side of the table is sunward and adjust your movement rates accordingly.
- In the regular 40k, Dark Eldar skimmers fit the trope to a T. Especially fifth edition ones released in November 2011.
- GURPS: Spaceships discusses solar sails. You can even give space boats wooden hulls if the setting demands it or the characters are incredibly desperate.
- One example is the Star Galleon which uses astral sails to move through space and designed to sail on a normal sea.
- The "Oceans Unmoving" storyline in Sluggy Freelance. This one wasn't space either, but flying sailing ships in a place outside time itself, which sailed above the frozen oceans of the title.
- This one was an interesting variation in that, although the ships' hulls looked like those of sailing ships, they could have masts on the bottom as well with additional sails.
- Oceans in the Sky features, very prominently, a sailing ship capable of space travel as a plot point.
- Grandpa's battleship in Homestuck, though The Medium is not exactly space. The white and black armies have such ships as well.
- The Douglas Adams game/novel Starship Titanic, one of the aforementioned Space Titanics. This particular ship also got a mention in Life, The Universe, And Everything.
- The RPG Rogue Galaxy.
- The airships in Super Mario Galaxy? Usually found in the sky, the game has Bowser's airship fleet flying through space in quite a few of the levels, notably Bowser Jr's Airship Armada.
- Vega Strike has Hidalgo. It's built by the Highborn faction as a luxury yacht, so extra-extra-fancifulness is to be expected. Space Pirates apparently like to misappropriate such vessels.
- At least one freighter model in Tachyon the Fringe has a strong resemblance to oceangoing ships.
- Futurama, the Space Titanic episode "A Flight to Remember". It survived Zapp Brannigan's decision to take it through a field of comets ("Ah, yes, comets, the ice-bergs of the sky!"), but then he had to steer it near "that black-ish, hole-ish thing". Also, a Dark Matter Tanker appears in "The Birdbot of Ice-Catraz" and a Pirate ship at the beginning of "Godfellas".
- Duck Dodgers featured a spaceship designed to look like an eighteenth-century pirate ship assaulting a spaceship designed to look like a nineteenth-century cruise liner. Also, the Klunkian (not Klingon) warship resembles a Viking longship, complete with oars.
- Codename: Kids Next Door had this when the candy pirates "modified" their ship for space travel (modifications consisted of an air bubble...thing and engines
- The 3-2-1 Penguins! episode "Runaway Pride at Lightstation Kilowatt" featured an entire setup of this, with a giant cargo spaceship and a lighthouse-like beacon that was set up on a beach-like asteroid with energy waves floating off of it.