A Look Inside The Space Shuttle’s First Printer

There was even a day not too long ago when printers appeared to be going the way of the dodo; remember the “paperless office” craze? But then, printer manufacturers invented printers so cheap they could give them away while charging $12,000 a gallon for the ink, and the paperless office suddenly suffered an extinction-level event of its own. You’d think space would be the one place where computer users would be spared the travails of printing, but as [Ken Shirriff] outlines, there were printers aboard the Space Shuttle, and the story behind them is fascinating.

The push for printers in space came from the combined forces of NASA’s love for checklists and the need for astronauts in the early programs to tediously copy them to paper; Apollo 13, anyone? According to [Ken], NASA had always planned for the ability to print on the Shuttle, but when their fancy fax machine wasn’t ready in time, they kludged together an interim solution from a US military teleprinter, the AN/UG-74C. [Ken] got a hold of one of these beasts for a look inside, and it holds some wonders. Based on a Motorola MC6800, the teleprinter sported both a keyboard, a current loop digital interface, and even a rudimentary word processor, none of which were of much use aboard the Shuttle. All that stuff was stripped out, leaving mostly just the spinning 80-character-wide print drum and the array of 80 solenoid-powered hammers, to bang out complete lines of text at a time. To make the printer Shuttle-worthy, a 600-baud frequency-shift keying (FSK) interface was added, which patched into the spaceplane’s comms system.

[Ken] does his usual meticulous analysis of the engineering of this wonderful bit of retro space gear, which you can read all about in the linked article. We hope this portends a video by his merry band of Apollo-centric collaborators, for a look at some delicious 1970s space hardware.

23 thoughts on “A Look Inside The Space Shuttle’s First Printer

  1. Fascinating article, Ken never ever disappoints!
    As for airborne data printers, I think the germans did it first in WW2 with the luftwaffe using the FuG 120 ‘Bernhardine’ miniature version of the Hellschrieber.

    1. Quote:

      “Due to the time pressure, the Shuttle teleprinter needed to be based on an off-the-shelf printer. Thermal and electrostatic printers were rejected due to toxicity and flammability problems.”
      (from the article linked to).

      But even so, putting in a 30kg behemoth with a launch cost of USD 1.5M for each launch seems quite ridiculous. But you can always rely on NASA to evaporate any budget given to them.

      Even when it was first created the whole space shuttle program already was quite redicilous to me. Sure, hats off for making it “work” for as long as it did, but even back then they already knew that they simply did not have the technology available to make a reusable space craft cost effective. What is the use of a “refurbishable” spacecraft if it results in launch costs that are 3x or more then that of the competitors? They did have the biggest payload capacity, and that was an important point, but launch costs per kg are supposed to go down with a bigger scale, not up.

      1. I’ve always wondered whether the space shuttle program was a cover for some military research into the efficacy of designing a reusable spacecraft. We have that for a few years now with the X-37B. A reusable craft would have civilian and military applications.

        1. Having something “re useable” implies surviving launches and recoveries. Wasn’t possible in the early days, was cheaper and easier to discard after the sucessful attempt particularly if money cost was no object. It wasn’t.

        2. If memory serves, the shuttle itself was built to be dual use, and the USAF wanted it and it did indeed fly several secret military missions, when the choice was that or bigger rockets for mars: I also think one of the original design goals is that it could do a take-off/polar-orbit/landing in one rotation, depending on where it was launched from.

          Happy to be corrected :-)

      2. Reading such statements over and over again makes me wonder if the typical US citizen has anything else in mind than money making, profits and making a business out of everything.
        No offense, but sometimes I wonder if you’re all Ferengis by heart.
        Because when I was little, it seemed to me NASA and the Shuttle program was about space exploration, research and science.
        I’ve always thought a space agency serves the citizens first and that it is being paid by the state and that it can use resources within a given budget.
        Looking backwards, though, I now think I was a naive fool.
        There was no prestige or magic involved, it was just about money making. As always.
        Greetings from EU.

    1. 1 US gallon = 3.78541178 liters

      So a liter of ink would cost (based on $12000 a gallon):
      $3170.06, which at the current rate of 1$ = €0,92 comes to €2916.46

      I’m not sure how much you can print with a liter of ink, but a lot of ink is wasted by using it to “clean” the printing nozzles (print head) or just thrown away because the printer fails (or refuses) to utilize it. To prevent confusion, we’re talking about inkjet printers here, which isn’t the topic of this article as that is about impact printers.

  2. I could see something printed as an asset on a space station if most their were power issue and one needed a low power backup to send hardcopy messages if monitors were fried or could not work.

  3. This explains the fairly surprising anecdote in Stephen Baxter’s mid-1980s, alternate history Mars missions https://en.wikipedia.org/wiki/Voyage_(novel) . It describes the use of a printer to produce each day’s astronaut schedule on the NASA Mars spacecraft. I always figured that by 1986, NASA would have been able to develop some kind of LCD-baed, Microwriter influenced, handheld data-logger. NASA was already familiar with the radiation-hardened, 1802 CPU; LCDs could easily be up to 128×128 (the Epson PX-8 and Tandy 100 achieved better than that); the DMA feature on the 1802 could be used to provide LCD refresh and its bootstrap mode would have enabled bespoke applications to be downloaded to an 8Kb or 16kB RAM model and used for checklists; data logging; or calculator functionality. Which reminds me – didn’t they use the HP-41CV calculator on the Shuttle?

  4. Linked article? Zoomable pictures? Diagrams? What the hell is going on?

    Why is this not a 57-minute Youtube video of some guy talking without showing us anything and glossing over important details?

Leave a Reply

Please be kind and respectful to help make the comments section excellent. (Comment Policy)

This site uses Akismet to reduce spam. Learn how your comment data is processed.