Horses have a time-honored place on interstellar colony planets. As with so much involving space, plausible or otherwise, I first encountered this image in the Heinlein juveniles. It probably gained its widest reach in popular culture more recently, in Firefly. I do not recall, now, whether the show explained why worlds settled centuries from now would have people riding around on horseback.
For a Heinlein reader no explanation was needed. Horses, he pointed out, manufactured their replacements, saving the expense of shipping them out from Earth. (Or the Alliance core worlds, or wherever advanced technology is firmly established.)
It was all quite plausible sounding. Which shot two varmints with one gun, because it also made Bat Durston seem plausible. He didn't need to sing to his trusty spaceship, or even give it a treat of sugar, because he could do those things with an actual horse. (Is sugar good for horses?)
Enough about horses. As you might anticipate from the title, this post considers a nautical variation of that trope, the use of sailing ships. My old future history had a colony world named Seychelle, a 'pelagic' planet with most its population living in the archipelago of Myrianesia.
The geology of such a world poses its own questions. Is Myrianesia a nearly-flooded continent, a supra-Hawaii shield volcano system, or some other type of feature not found on Earth. Could a planet with minimal dry land develop complex life, or even be suitable for terraforming?
But given such a world, much of its transport would have to move by sea, even at early stages of colonization. Limited and costly imports of marine technology invite solutions utilizing local materials and power sources - and wind power for sea transport is a technology known to work.
Sailing ships, unlike horses, do not reproduce. (D'oh!) But they don't need fuel, and the power plants presumably won't need to be imported from Earth. Nor require teams of outrageously specialized maintenance techs to keep them running.
Technical considerations aside, when it comes to the Rule of Cool, sailing ships rank very high, and that of course is the real motivation for this discussion. In my future history, Seychelle becomes one of the most important colony worlds, center of a trading empire. By that time it is industrialized enough that sailing vessels are no longer the basis of local surface trade. But the sail seamanship tradition has become part of the culture, and part of the training of University starship crews.
A link to Atomic Rockets for the hell of it, though it has no page on sailing ships, if any mention of them at all.
It all seems rather pretty (for values of pretty that resemble mine), and even plausible. But the inevitable niggles arise. Sailing ships don't require lab-coated techs to keep them going, but they do require rated able seamen, and in substantial numbers.
To put things in historical perspective, steam was making major inroads into ocean trade by the mid-19th century. By the start of the high industrial era, about a century ago, sailing ships survived only in marginal trades. And that was in competition with steam engines that by today's standards were, well, steampunk technology - massive, clumsy, inefficient maintenance hogs.
Which - alas! - makes it hard to believe that a robust young colony would would not be able to find better solutions (cheaper, faster, easier to maintain, etc.) for its maritime transport needs than sailing vessels, no matter how beautiful to the romantic eye and mind.
Backslidden colonies - another popular operatic trope - might be a somewhat different matter. I am not quite sure that even backslidden worlds would simply recapitulate the terrestrial past. If they retain partial knowledge or capabilities they might have an odd mix of techs. If they lost practically everything their eventual rebuilding could be unlike any of our familiar images. (For one reference point, compare Chinese junks to western ships of comparable techlevel.) But backslidden worlds may be a topic for another post.
A more meta response is to say that any setting with colony worlds sufficiently Earthlike for oceangoing ships of any sort is, for all practical purposes, space opera. And space opera is essentially a branch of fantasy with SF trappings. It is not just beyond the Plausible Midfuture: It has no more to do with the PMF than dragons do, and niggles about its technology are merely ... niggles.
The equally meta response to which is that the (pseudo-) plausibility of worlds is part of their essence. A world with flying sailing ships is one sort of beast. A world that purports to have recognizable schooners sets itself a different standard for the willing suspension of disbelief. And having set that standard it must live up to it, or pay the price of not quite seeming believable to the reader.
