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Very little of the thousands of hours of Mission Control audio on the website has been heard or documented. As you find moments of interest, post them here for discussion.

Author Topic: How to listen to Control (LM GNC) backroom Apollo 13 after accident  (Read 2103 times)

Offline kendradog

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I am having difficulty navigating the site in an iPad.

Specifically, when I try to select LM/GNC, which I suppose is CONTROL, around GET 57:00:00 I get 99% standard flight director loop, but with an echo. There is some GNC backroom chatter but it’s rare and hard to hear. What’s the best way to listen to the CONTROL (LM GNC) backroom loop ?

I also can’t figure out how to usefully listen to Telmu or INCO after the accident.

By contrast the EECOM backroom is completely clear.

Offline MadDogBV

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Re: How to listen to Control (LM GNC) backroom Apollo 13 after accident
« Reply #1 on: July 03, 2023, 08:14:34 am »
Hi there,

Yep, it's a known bug and not associated with a device, because some of the tapes "blended" together as a result of a wander effect. Ben Feist explained in a separate thread as follows:

Quote
Hi everyone. Yes, unfortunately that track was not digitized on the original playback. We plan to run the tape through one more time in order to capture it properly this time.

As for the audio being mixed up at various parts of the mission, yes, you're not going crazy, this is happening. We believe the old tape machine isn't properly tracking the tape, causing it to wander across channels. There is a pending fix for this but again, will take time. The best thing to do right now is to check the adjacent channels if you think you're hearing the wrong channel.

It's a shame, because those tapes are some of the most important during the entire incident. The scramble that took place in the LM SSR backrooms in order to quickly pull up, tweak, and then send out procedures to activate the LM, as well as to work on subsequent powerdown profiles, is one of the most significant achievements in mission control in the entire space program.

The NETWORK tape is also affected and is noticeably blank although there is a NETWORK on duty.

Best way I found to listen to INCO was actually to download the INCO and PROCEDURES tapes from Archive.org in John Stoll's MOCR collection, and then splice them together in GoldWave/Audacity so that INCO was on the left speaker and PROCEDURES was on the right speaker. The two positions, despite being nominally different, actually worked in concert with each other in order to interface with MSFN and maintain uplink/downlink with the spacecraft. This is evident during the accident as well.
« Last Edit: July 03, 2023, 08:18:51 am by MadDogBV »

Offline kendradog

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Re: How to listen to Control (LM GNC) backroom Apollo 13 after accident
« Reply #2 on: July 04, 2023, 04:01:20 am »
Thank you for this information. If I understand correctly, currently CONTROL is unavailable for the accident period.

If you have a link to your spliced INCO/PROCEDURES tape, that would be interesting.

I thought Glynn was just about ready to lose it when INCO said there would be a 2-minute data loss for some reconfiguration and it took 20 minutes or more. INCO even on the FLIGHT loop just after the accident is interesting to listen to, as the controller is incredibly laconic and calm but one can tell a lot is going on behind the scenes.

For what it’s worth, I still observe many issues viewing the site on iPad.

 Re the CONTROL tape, ideally there’d be a site release notes that describes key outstanding problems so users don’t waste time rediscovering known issues.

Offline MadDogBV

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Re: How to listen to Control (LM GNC) backroom Apollo 13 after accident
« Reply #3 on: July 04, 2023, 10:07:36 am »
What's happened is CONTROL and TELMU have blended together onto CONTROL's loop, and unfortunately there's about a 1-second delay between both transmissions so that's why it sounds like there is an echo. The TELMU channel on the website is nonfunctional at least during this phase on the mission. I think later on, they begin to separate out.

Quote
I thought Glynn was just about ready to lose it when INCO said there would be a 2-minute data loss for some reconfiguration and it took 20 minutes or more. INCO even on the FLIGHT loop just after the accident is interesting to listen to, as the controller is incredibly laconic and calm but one can tell a lot is going on behind the scenes.

There was indeed a lot of off-radio chatter that you didn't hear on the tapes. ;D Lunney has TELMU (Merlin Merritt) in his ear both on and off the loops begging him to get the power load reduced, and the flight dynamics people are champing at the bit to get the spacecraft on free return, so Lunney is impatient to get good comm established with the crew. It's very clear on even the FLIGHT loop that he has a difficult time hiding his anger over the comm being lost for a long period of time. Throughout the INCO loop during that incident, you can hear Ed Fendell make remarks like "I have to fight the flight director off -- here he comes" and "I've got a monkey on my back now" and "you guys have really done me in", which would seem to indicate he got chewed out off the loops.

A similar incident happens toward the end of the mission when the CM (now separated from the service module) is performing its final alignment prior to LM sep and re-entry. INCO (Tom Hanchett) struggles to establish comm and data with Odyssey during a phase of the mission when GUIDO (Ken Russell) and YAW (Bill Pressley) are in a hurry to uplink commands, losing data four or five times in the process. Gene Kranz, as steely as they come, has a better time concealing his anger than Glynn Lunney, but even he lets out an audible sigh of irritation over the loops after they break lock for the third time. "INCO, what's your problem?" When they have an opportunity to go back on high bitrate after downgrading to low to lock on solid, Kranz refuses INCO's request to do so, having lost faith in the stability of the comm.

It's important to note that Fendell and Hanchett are very competent men, having been involved in the space program for years even through the Mercury and Gemini days. The procedures, however, are only as good as the training that they receive. So when the flight controllers write up the mission operations report at the end of Apollo 13, both INCO and PROCEDURES will openly slam the poor quality of the sims as far as communication failures are concerned:

Quote from: Apollo 13 Mission Operations Report, Page I-5
A number of attempted communications failures have been incorrectly simulated such as an attempt to fail the entire USB downlink but failing to inhibit the crews downlink voice. These mistakes provide INCO negative training in resolving communications anomalies as well as causing the Flight Director to lose some confidence in INCO."

As far as the spliced INCO/PROCEDURES loop -- I'll upload them on Google Drive and share a link at the next most opportune time!
« Last Edit: July 04, 2023, 10:21:28 am by MadDogBV »