Apollo 13 accident: understanding Houston’s real time debug (Apollo Comms Part 28)

We open up a Block I Apollo AC inverter, which gets us totally sidetracked into the Apollo 13 incident. Using the original schematics, looking how our inverter was hooked up in the power system, we can follow word for word the Apollo 13 raw audio of the debug after the accident. I will go into much more engineering details than what is usually reported, but once you understand this, the flight control loops become both limpid and downright chilling. And then, when we regain our composure and get back to said inverter, more surprises await.

Apollo 13 incident composite loop is on my website here:

An even better way to listen to the Apollo 13 audio is to go to:
Select "join at launch-1minute", then pause it and go to mission time 55:54.
To get an even better listen, go to the Mission Audio Control tab, and click on EECOM. You'll hear even more of the backroom discussion between EECOM and EPS

The episode about the fuel cell is here:

Links to doc:

Music Credit: Crinoline Dreams by Kevin MacLeod

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[mikesradiorepair]

Quote: "The best 2 1/2 hour customer service call you will ever hear." Best quote from CuriousMarc ever!

[TeslaTales]

Sir, this episode was the best analysis and discussion of 13 I've ever seen.

[merseyviking]

The fact that the engineers put in the ability to switch all things to all other things shows great foresight. And the calmness of the whole crew never ceases to amaze me.

[mahtin]

Was I alive at Apollo-13’s flight? Yes
Did I follow the flight in 1970? Yes
Did I read lots about it since then? Yes
Yet today, Marc provided the best commentary I’ve heard. I think because of the step-by-step explanation alongside a diagram annotation. Thank you!

[gavincurtis]

The power distribution explanation was the most fascinating “sidetrack” I have experienced in a long time.

I totally forgot about the inverter.

[StringerNews]

Wow. I was just a kid when it happened, and remember going to bed with the expectation that the mission and astronauts would be no longer by morning. The audio reinforces just what a dire situation it was. The fact that all three astronauts made it home alive was due to a LOT of methodical and exhaustive planning! That planning gave them options when there were almost none available. Well done!

[jasondugas]

NASA engineer of 20+ years. This nearly brought tears to my eyes. Thank you for the great work and even more for the great video editing, etc.

[georgemachappy]

No pressure but if you felt like doing a full 2.5hr technical/schematic read-along of the incident, it might be one of the most fascinating videos in existence about the subject. Like some other people, I forgot this video was about the inverter and was sucked into the illuminating companion narration. I wish I was, like you said, an “Apollo spacecraft power system expert”, but I’m afraid even with the core concepts down, the insights of the logic behind the troubleshooting would be missing and are priceless.

[SM-rnxy]

Vermiculite does not always contain asbestos - its still available and in use today for fire protection. Might be worth getting the stuff you removed tested if its still available. Another great Apollo 13 episode 👍

[ksbs]

I had butterflies in my stomach as Marc narrated the terrifying minutes as everything was falling apart. This retelling of the events had a much larger emotional impact on me than any article or the magnificent Apollo 13 movie. Well done!

[tekvax]

Marc, This is the most comprehensive, thorough, and amazing description of what happened during A13, and how the system functions! Once again, you've knocked it out of the park sir!

[guynardin]

Oohhh meen.. I love this episode.. Thank you so so much... I read so many books and videos about the accident and now you share this guts details of it... tears of joy. Thank you thank you!!!

[johno]

24:20 As a teenager in the early 90s I was lucky enough to sit next to John Aaron (EECOM) for 14hours on a flight from Sydney to LA.
He enthralled me with stories of Neil Armstrong and his work in Apollo 13.
Pity I wasn't older or I would have hammered him with more questions.
I remember he introduced himself "Hi I'm John Aaron, I taught Neil Armstrong to land on the moon."
Something he was very proud of. 🙂🇦🇺

[crowguy]

That inverter looks like a perfect candidate for one of those CT scans(obviously sealed in plastic bags the whole time).

[nigeljames]

That was one roller coaster of a video. I learned a lot of the Apollo 13 dysfunction (?) it was great to see the block diagram and the original dialogue as they tried to work out what had gone wrong. Thanks again for your efforts !

[williamsquires]

Where’s Scotty when you need him? 😂 The quality and professionalism of these people in the Apollo program was simply amazing. Hats off to those people!! 🎉

[GrantWyness]

Ooh, I so didn’t want this episode to end…

[simonpritchard]

Your 'sidetrack' was probably the most gripping piece of youtube video I've ever seen -- an excellent explanation of a sequence of events that I've never been able to fully follow before now. Thank-you!

[kargaroc]

EECOM: I want to power down a total of 10 amps, flight
FLIGHT: A total of ten amps!
someone else: *surprised whistling*

[Petertronic]

The technical walkthrough, with diagrams and audio from all the Nasa engineers, was *incredible* - that deserves to be made into a separate dedicated new series!!