What Are Star Trek's Jefferies Tubes, And How Did They Get Their Name?

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Jefferies tubes are, as Trekkies can tell you, the official Starfleet name for the network of crawlspaces that snake throughout an average Starfleet vessel. Non-Trekkies might remember the multiple scenes throughout the original "Star Trek," wherein Scotty (James "Definitely not a Scot" Doohan) was perched inside a diagonal space tinkering with the USS Enterprise's computerized plumbing. Jefferies tubes were seen more extensively in "Star Trek: The Next Generation," and the engineers on the USS Enterprise-D were often depicted as crouching down in the crawlspaces to go repair esoteric parts of the ship. On the Enterprise-D, the Jefferies tubes were seen as even more cramped than on the original "Star Trek." One can crawl through them, but it seems like it would be difficult to turn around. 

It was explained in several "Next Generation" episodes that Jefferies tubes are plentiful throughout the ship and that they can be used to traverse the entire length of the Enterprise, should the turbolifts break down. Jefferies tubes come up often in "Star Trek," having made appearances on almost every series to date, as well as three of the "Star Trek" movies. On "Star Trek: Lower Decks," Jefferies tubes were much larger than ever before; two officers could semi-comfortably hang out inside of them. 

The name of the Jefferies tubes is a double tribute. Within "Star Trek" canon, they are named after a fictional engineer who has never appeared on screen, and who first helped design the original Enterprise ship back in the 22nd century. That fictional engineer was named W.M. Jefferies. 

That fictional engineer, however, was an in-joke that was named after a real-life art designer named Matt Jefferies (1921 – 2003) who helped with the initial sketches of the USS Enterprise behind the scenes on the original "Star Trek."

Herbert and Yvonne Solow's sourcebook "The Star Trek Sketchbook" quoted Matt Jefferies on the matter, and it seems that he didn't name the Jefferies tubes after himself. Someone else, while sketching out some set designs, decided to name the crawlspaces after Matt, and the name caught on with other designers. "Somebody hung the name Jefferies Tube on it," Matt Jefferies said. "It wasn't me, but the name stuck, and I used it in some of my sketches!"

The on-set/scripted origin of the term "Jefferies tube" is a little amusing, and was told on the DVD special features on the original "Star Trek" series. The term wasn't written into one of the "Star Trek" scripts until the episode "Journey to Babel," the 10th episode of the second season. The set builder on that episode was John Jefferies, the younger brother of Matt Jefferies. Matt had designed the set, and John had to aid in building it, so everyone, even the writers, knew what was what; the tubes were a winking tribute. Fans got to know their name, though, through non-canonical sourcebooks and blueprints, so eventually Trekkies got to play along.

The term "Jefferies tube" was finally said out loud in dialogue in the "Star Trek: The Next Generation" episode "The Hunted," which aired in the show's third season. That was in 1990, so it took 24 years after the term had become a well-known in-joke to become an actual piece of official "Star Trek" lore. 

Of course, once the term was officially in place, the writers of future episodes of "Star Trek" had to manufacture a reason why the tubes were named Jefferies in future episodes. And they did just that on the 2001 series "Star Trek: Enterprise."

It should be recalled that "Star Trek: Enterprise" is about the very first Starfleet vessel that took to stars on a prolonged mission of exploration and diplomacy. That ship was the (highly ranked) USS Enterprise NX-01, the first ship capable of flying faster than Warp-5. Naturally, a lot of that ship's designers and engineers are namechecked in episodes of "Enterprise," and the writers of the series took this as an opportunity to make the designer of Jefferies tubes a canonical figure. 

In the episodes "Home" and "First Flight," one Captain W.M. Jefferies is mentioned, and he is said to be one of the chief starship designers in the NX program. Charles "Trip" Tucker (Connor Trinneer) would serve under Captain Jefferies, and eventually become the chief engineer on the Enterprise. 

Of course, we're only inferring that Captain W.M. Jefferies invented the Jefferies tube from his name. If one wants to be a real stickler (and Trekkies love to be sticklers), the inventor of the Jefferies tube was first named in the 1990 "Star Trek" tie-in novel "Home is the Hunter" by Dana Kramer-Rolls. That book noted that the tubes were actually invented by an engineer named Frederick William Jefferies. Thanks to the timeline of "Enterprise," though, expanded universe-loving Trekkies can backtrack his lineage to Captain W.M. Jefferies, and posit that Frederick was W.M.'s grandson. "Star Trek" novels, however, are not considered canonical, so this is only an additional detail to ponder in an already persnickety piece of over-nerding. 

This entire article merely proves, however, that a lot of in-jokes, production details, and non-canonical sources go into the naming and designations of everything in "Star Trek," right down to the nicknames of the crawlspaces on a starship. Real nerds know.