scottmanley
patreon
Mariner I Research - Some 'Light' Reading
🕑 Added 2019-05-15 21:51:56 +0000 UTCThe 'Why Rockets Fail' series has been something I wanted to do for years, but I always wanted to start with Mariner I - it was supposed to be the first space probe sent to another planet, but instead ended up in the ocean after a guidance failure. And the root cause of the guidance failure was a programming error in the computer.
Arthur C. Clarke wrote several years later that Mariner 1 was "wrecked by the most expensive hyphen in history".
However simple this may sound, it's never been enough for me, I'm a programmer and I like to pick apart code, I originally wanted to see if I could find some post incident report that included the details, but I turned up a blank. Instead I've returned to the problem occasionally over the last few year. So instead I've tried to piece together the details from other documents.
And so here's the video I made:
https://www.youtube.com/watch?v=0LJz-TWV3so
But more importantly, here's the sources that really turned out to be important in the end:
While the Wikipedia page has a lot of info, it misses a few important documents:
https://en.wikipedia.org/wiki/Mariner_1
NASA's page on Mariner included this phrase: "omission of the hyphen in the data-editing program caused the computer to incorrectly accept the sweep frequency of the ground receiver" which sounded interesting, but I didn't know exactly how all this worked
https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=MARIN1
This document from 1964 investigated repurposing the old guidance systems had a lot more detail on the operation of the ground systems
https://apps.dtic.mil/dtic/tr/fulltext/u2/358574.pdf
The code wasn't run on the rocket itself, the autopilot was too simple, instead it was a Burroughs designed computer on the ground:
http://afspacemuseum.org/displays/BurroughsComputer/Burroughs_Historical_Summary.pdf
Convair published a specification for the booster which also included a lot of clues as to how the systems interacted:
https://apps.dtic.mil/dtic/tr/fulltext/u2/486484.pdf
NASA History on the Atlas Mercury includes another description of the flight control system, and some block diagrams (5-10, and 5-11) of these, even though this was a different program they were ultimately managed by the same people
https://history.nasa.gov/SP-45/ch5.htm
JPL's report on Mariner II also included a timeline for the Mariner I failure
https://history.nasa.gov/SP-59.pdf
And a personal account by the Air Force Officer who was the program manager for the Ranger & Mariner programs, his account of the incident is probably the most readable of these documents.
