I just won a very cool artifact, the first flown Command Module sextant from the Apollo program. AS-202 was the second unmanned test flight of a production Block I Apollo Command/Service Module, launched with the Saturn IB launch vehicle in 1966. This was the first flight of the guidance and navigation system as well as the fuel cell electrical system, to validate their use for the first manned flight. But, the subsequent flight became what is now known as Apollo 1, ending with a tragic fire on the pad and prompting a redesign of the wiring for much of the Block I hardware.

Following the mission, this sextant was returned to the manufacturer, Kollsman, for post-flight inspection and evaluation.

The sextant determines the Command Module’s position and attitude with relation to stars or landmarks. This data was then supplied to the onboard computer to calibrate the spacecraft’s Inertial Measurement Unit (IMU).

5 responses to “The original Apollo Sextant from flight AS-202”

  1. jurvetson Avatar
    jurvetson

    The sextant measures 22 x 11 x 14, bearing a parts tag on the main metal housing, reading: “Apollo G&N System Optical Unit, Part No. 1011000-004, Serial No. KIC 12, Cont. No. NAS 9-497, Designed by MIT Instrumentation Lab, Manufactured by Kollsman Instrument Corp.” Below the tag is the yellow text designating the piece as flight hardware, “Flight 202.” Looking from above:
    Looking at the other side
    And the inner core element, from a Block II version I have on displayApollo Block II Sextant

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  2. jurvetson Avatar
    jurvetson

    As mounted with IMU ballApollo Command Module Inertial Measurement Unit (IMU)</script

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  3. sonodocsch Avatar
    sonodocsch

    Though I was not the person who consigned that optical unit assembly to RR, I bought that sextant from a former Kollsman employee years ago. Kollsman had it on display when they were located in Elmhurst, NY. When they moved, they decided to sell off some of the things they had on display. Employees got the first chance. I actually found it through an advertisement in Sky & Telescope magazine (none of my space collector friends thought it would work). It came with the Block I nav base assembly. There are some eyepieces for the optical unit that will be coming up in the RR 2022 spring Space auction though the sextant eyepiece is a Block II version. The Block II sextant optics section you have is a rare one. NASA considered adding a star tracker to the sextant, but eventually decided there was not enough time to get it fully tested. The optics section you have has the star tracker parts in it. The only complete sextant I know of that has this is the one on display at the Adler Planetarium in Chicago. The Smithsonian has several, but I’ve only seen photos of those and they don’t show the optics side, usually just the cabin-facing side.

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  4. jurvetson Avatar
    jurvetson

    [https://www.flickr.com/photos/195022785@N06] wow, Steve, thank you SO much for the back story and detail. Do you happen to have anything related to this still? Perhaps for sale? 🙂

    I just posted a writeup on the control panel that would have been right under this optical unit hereApollo 2 Command Module G&N Indicator Control Panel

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  5. jurvetson Avatar
    jurvetson

    And here’s a digital recreation video of the AS-202 flight, which was also the first flight of the Apollo Guidance Computer.

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