Lunar Module circuit breakers used mechanical trip mechanisms that could be manually overridden or broken
the verdict
SUPPORTED
the evidence backs this
refutedsupported
the weight of evidence
1 source for · 0 against
AS REPORTEDno primary record reached; this is what the reporting says
Historical accounts and Apollo mission logs report that Lunar Module circuit breakers could be manually pushed or inadvertently broken off during operations, as famously occurred with the engine arm circuit breaker on Apollo 11.
# How did LM circuit breakers operate? (famous engine arm CB broken by Aldrin)
Tags: apollo-program, apollo-11, lunar-module
- Score: 11
- Views: 2057
- Answers: 3
- Answered: yes
- Asked by: Sergiy Lenzion (6505 rep)
- Asked: 2019-11-21
- Edited: 2019-11-21
- Site: space
## Question
From Apollo Lunar Surface Journal:
"112:56:28 Aldrin: Houston, Tranquility. Do you have a way of showing the configuration of the engine arm circuit breaker? Over. (Pause) The reason I'm asking is because the end of it appears to be broken off. I think we can push it back in again. I'm not sure we could pull it out if we pushed it in, though. Over.
[Aldrin - "There weren't guards over any of the circuit breakers. One got pushed in and one got broken off. So I must have pushed one in and broke one off (with his PLSS prior to doffing)."]"
The broken tip of the CB and the pen:
Image source: (http://www.collectspace.com/review/apollo11_circuitbreaker02-lg.jpg)
LMP circuit breaker panel:
Image source: https://www.hq.nasa.gov/alsj/a12/LM6-co04.jpg
How were circuit breakers in LM operated? Push for "ON", pull for "OFF"? Or push for "ON" and push again for "OFF"? If it's the former (which would explai