10 Greatest Star Trek In-Jokes

Walter Mathew 'Matt' Jefferies (his full name is of importance later) is the man well known for designing the original Enterprise model, now so iconic it hangs in the Smithsonian. Jefferies was also largely responsible for the majority of the Enterprise's interior design, as well as that of the shuttlecraft, the Klingon D7 Cruiser, the hand phaser, and a plethora of other props, sets, and landscapes.

As shown in The Star Trek Sketch Book: The Original Series, Jefferies equally designed what he called the "engineering power shaft" in his sketch for The Enemy Within. As he recalls:

We needed a space where Scotty could fix things without taking up too much room. So I made a tube with all kinds of complicated-looking stuff in it […] Somebody hung the name Jefferies tube on it […] [and] the name stuck.

And stick it did, but only behind the scenes on TOS. It wasn't until The Next Generation season three episode The Hunted that the term 'Jefferies Tube' was said on screen. On TOS, designers also liked to add the label 'GNDN' for 'Goes Nowhere, Does Nothing' to the pipes on the Jefferies tube sets. In canon, it is generally accepted that the famous crawlways were named after NX project engineer of the 22nd century, W.M. Jefferies.