# Spacecraft Changing Direction Terminology

Most science fiction writers have chosen to adopt (for various reasons) naval terminology for their ships. While this does make some sense, one thing that I can’t ever recall is anyone having a term if they want the ship to go “up” or “down.” Ship captains will frequently call out, “Port” or “Starboard,” but the only time I can think of when a captain ordered his ship to change “altitude” was in Star Trek: The Wrath of Khan, when Kirk says, “Zee minus ten thousand meters.” So has anyone come up with terms, or is it just something that authors have glossed over?

Up and down are pretty unambiguous, compared to port and starboard, which came into use because left and right depend on which way you’re facing on the bridge. (At least I think so.) Port and starboard clear this up by essentially assigning left and right relative to the vessel’s current orientation.

One thing that star trek often does get right in terms of up-down and space having three dimensions, is that they call out direction changed in terms of a pair of angles. For instance, making this up, “Set a heading of two-two-seven, mark fifteen, and engage.” Now, it’s not clear exactly what the conventions of this are, but I think the usual implication is that the first number is how much to rotate in the horizontal plane, and the second indicates how much to tilt up or down. Perhaps two hundred and twenty seven degrees to the left, (or three-eights of a full circle to the right approximately,) and fifteen degrees up. Using combinations like that, you could easily represent every heading within a three-dimensional sphere, like using latitude and longtitude to represent a point on the earth’s surface, or declination and right acension to pinpoint a star.

Now, to find different stars you need to find some kind of reference point for your X Y Z co-ordinate system, possibly with X being towards the galactic center from earth, Y being perpendicular to that direction within the galactic disc, and Z heading towards the edges of the galactic disc, if that makes any sense.

As a matter of fact, the ST:TNG technical manual says the xxx.yyy co-ordinate system can be used in 3 ways, IIRC. Most common is “relative coordinates”, or something like that, with 0.0 representing the current heading of the ship, 90.0 being a right turn, etc. The others were relative to the center of the galaxy and relative to the solar system, I think.

I thought they typically referred to “pitch” as changes in up & down heading, but I can’t think of a specific example.

To indicate the orientation of the spacecraft or a rotational motion, real life spacecraft use the terms Pitch (up and down), Yaw (left-right), and Roll (rotate along long axis). For linear motion on three axises there are the terms Heave (up and down), Surge (forward, back), and Sway (left to right).

Mork once said that you had to “hang an up” to get to his home planet.

Actually, there’s an episode where Wesley explains the system to…someone or other…and this is exactly how he explains it.

Now, I’m off to stab my brain until that useless little factiod has been deleted.