Sciency Words: DSKY

Sciency Words PHYS copy

Continuing with the 2015 Mission to the Solar System, we now come to the Moon (Earth’s moon, in case there’s any confusion). The most important fact about the Moon is that human being have actually been there, so for this week’s edition of Sciency Words, let’s look at a term that was closely tied to the Moon Landings:


Pronounced “dis-key,” this term is an acronym for “display and keyboard,” and it served as the main computer interface for astronauts during the Apollo Missions. And I cannot emphasize this enough: DSKY was not exactly “user-friendly.”

Apollo astronauts issued commands to their guidance computer by entering a “verb” followed by a “noun.” The computer would then perform the indicated verb on or with the indicated noun. Verbs included things like “display” or “enable” or “initiate.” Nouns could be parts of the spacecraft, countdowns, preprogrammed maneuvers, etc.

That seems simple enough until you see the interface itself. It’s just a number pad with a few extra buttons (note the two on the left labeled “verb” and “noun”).

My01 AGC_user_interface
You can land on the Moon using just nineteen buttons… assuming you know which buttons to push.

This system is not even a little bit intuitive. Turns out every noun and verb had specific two-digit numbers assigned to it. How did astronauts know which number combinations to use? They had to memorize them.

As user-unfriendly as it may seem, DSKY actually simplified the Apollo Missions by reducing the total number of keystrokes required to operate the guidance computer. If you’re trying to land on the Moon, would you want to type out “please perform landing and breaking phase” or would you rather just hit six buttons: “verb-5-0, noun-6-3”?

In fact, Apollo astronauts reported that DSKY was surprisingly easy to use. One astronaut compared it to playing the piano. Once you familiarize yourself with the keys, your fingers just know what to do.

But that’s only true after you’ve learned the interface. You need training. A lot of training. I’m willing to bet even experienced pilots from NASA’s Space Shuttle Program would not necessarily be able to figure out how to use the DSKY interface from the Apollo Missions.

This is one of my biggest pet peeves in science fiction: characters sitting down at unfamiliar control panels and somehow instantly knowing how to use them.

But maybe I’m wrong about this. Maybe computers on spacecraft will become more user-friendly over time (based on my research, that has not yet been the case). So what do you think? If we ever build something like the starship Enterprise, how easy or difficult will it be to learn the user interface?


Apollo Flight Journal from NASA History Division.

Computers Aboard the Apollo Spacecraft from Computers in Spaceflight: The NASA Experience.


7 thoughts on “Sciency Words: DSKY

  1. The thing about modern spacecraft (or aircraft) is that the builders don’t necessarily have the money to build everything they want into them… including robust and reliable interfaces that do everything possible at high efficiency. So they create hardened and simplified controls, supposedly easy to use once you’re trained on what does what.

    But as automation, sensors and computer systems improve (and costs for all that equipment drops), we should expect someday that interfaces will be able to better understand operator needs, process multiple detailed instructions based on simple requests and handle automated tasks without being guided by human hand-holding.

    I think we’re on the cusp of that transition now.

    Liked by 1 person

      1. Advanced commercial aircraft are already capable of handling flight and landing (not positive about takeoff); as time progresses, we could see automated systems doing more of the flying, with pilots there to monitor the automation and provide an occasional assist, not the other way around. Aircraft will also keep better track of themselves, using GPS and plane-mounted radar instead of relying on data from ground-based radar or physically spotting ground-based beacons. They’ll be able to communicate with other aircraft, so they won’t need ground control to warn them of imminent collisions.

        (After the recent crash in the Alps, commercial fliers are looking at existing military flight systems, which can automatically pull up a plane flying into terrain. Such systems will aid existing automated flying systems.)

        And all of these systems are benefitting from natural-language interfaces, automatic translation and non-jargon-based interaction.


      2. I hadn’t heard about aircraft being able to land on their own. I guess that spoils the classic dead pilot plot device.

        So do you envision any need for special training in order to be able to pilot futuristic aircraft?


      3. I’d expect training to evolve into a more instruction-based, less hands-on process; in other words, I expect a plane to be able to take commands from pilots, and pilots to either let it do its job, or in extreme situations, give the plane orders of what to do next. Future pilots may sound more like today’s trainers out in the field (or in the air), instructing a plane’s A.I. to adjust approach angle, throttle up to compensate for wind speed, trim so many degrees, etc, as the plane does the actual landing.

        In a pinch, pilots may still actually handle a wheel or stick, but as most of the controls today are already fly-by-wire, he is still essentially showing the plane’s A.I. what to do.

        OR… when a plane has an internal problem, it may be more effective to hand the controls over to remote pilots (or A.I.) to bring it in safely. Except in situations of radio failure, there might be no need for actual pilots on-board an aircraft in time. (In the case of a complete power failure, even today’s pilots are helpless to operate a fly-by-wire system, and the plane is doomed.)

        Liked by 1 person

  2. I read somewhere that the Apollo program would have been infeasible without the onboard computers. The point was that computer technology came along at just the right time. If Apollo had been attempted in the 50s, the onboard computers would’ve been impossible, and it’s hard to imagine astronauts doing the calculations by hand in the time required.

    I think computers on spaceships will likely get easier, but in the sense that they’ll probably become the pilots. I suspect when self driving cars become commonplace, and we discover that they work better than human driven cars, the idea of a human “operating” a spaceship, except in the broadest sense of supervision, will increasingly be seen as something we just don’t want to do.

    Liked by 1 person

    1. That makes sense. Based on what I read, the astronauts seemed to be highly dependent on their guidance computer. They often referred to it as the fourth crew member.

      I guess if futuristic spacecraft are fully or almost fully automated, perhaps obeying voice commands, they could be really easy to operate.

      Liked by 1 person

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