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Author Topic: 057:53:58 Kamman and Hutchinson need quick and dirty answer on IMU heaters  (Read 3400 times)

Offline MadDogBV

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This is one of the greatest examples of having to evaluate quick decision-making during a crisis, in the midst of what is likely considered the apogee of peril during the Apollo 13 mission, minutes before an imminent shutdown of the CSM and the LM not yet being operational.

GNC Jack Kamman makes a call to an IMU heater expert to determine whether the heaters need to be powered up for the crew to return home safely. Then someone else jumps into the call in the nick of time to clarify the nature of the question. The person they are calling is probably Dick Freund, based on the dialogue in the call as well as the fact that he makes reference to "AC doing a study". That "AC" is ACDelco, a subsidiary of General Motors. They were the manufacturer of the IMU used inside the command module, and in the flight controller assignment list, Dick is identified as an employee of that company.

https://apolloinrealtime.org/13/?t=057:53:58&ch=18
« Last Edit: September 09, 2023, 11:12:13 am by MadDogBV »

Offline kendradog

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Re: 057:53:58 Kamman and Hutchinson need quick and dirty answer on IMU heaters
« Reply #1 on: September 11, 2023, 04:25:17 am »
One of them says that they are "down to one fuel cell". I'm not sure if Dick Freund understood fully that they would soon have not one but rather zero fuel cells remaining in about 10 minutes.

I love these dialogs between the specialists in one system who want the whole spacecraft to support that system and the Flight Director. It was critical that Flight, whether Gene Kranz or here Glynn Lunney, understood the technical details and how they all fit together and could make key decisions.

This also reminds me of the Kranz speech in the movie about how they want to contact every person who built every component on the spacecraft. It is kind of impressive that they could quickly get to the IMU or IMU heater manufacturer to get a quick test of how it would respond to cold temperatures. It's really rather extraordinary, that means of all the thousands of critical components in the entire spacecraft, NASA must have had the manufacturers standing by for immediate, expert advice and even testing. What an amazing time.
« Last Edit: September 12, 2023, 10:53:16 am by kendradog »

Offline bfeist

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Re: 057:53:58 Kamman and Hutchinson need quick and dirty answer on IMU heaters
« Reply #2 on: September 11, 2023, 10:13:50 am »
Today Mission Control uses a similar structure where the engineers who designed a piece of equipment are available during EVA. They sit in a room called the Mission Evaluation Room (MER) and when the crew runs into a problem such as a bolt that won't turn, the person who can answer the exact torque tolerances of that bolt is available on the loop. I don't know what the history of this structure in mission control is, but it's very likely that it's due to the occurrences that happened during apollo 13.

Offline MadDogBV

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Re: 057:53:58 Kamman and Hutchinson need quick and dirty answer on IMU heaters
« Reply #3 on: September 11, 2023, 01:57:12 pm »
There was definitely an operational MER during Apollo 13. Throughout the mission on most of the loops - the first 2/3 of the Kranz shift just before the accident is a good example - the controllers make reference to Building 45 and Don Arabian. Bldg. 45 was the location of the MER, and Don Arabian was its leader. During that shift, he and the SPAN bigwigs (Joe Roach and a few others) talked about how they were going to bleed down the SHe (supercritical helium) if the telemetry showed excessively high readings during the LM pass.

The problem apparently was so critical that when Kranz called up SPAN to let them know he was powering up the LM early, there was nobody available in SPAN to give him either a go or no-go. The controller who answered him, Bill Blair, was a North American contractor. 😅

Link: https://apolloinrealtime.org/13/?t=053:22:11&ch=50

During and after the accident, the MER spread out to encompass nearly the entire Manned Spacecraft Center as they vacuumed up controllers and contractors, working furiously to develop procedures and solve imminent problems regarding the spacecraft. John Wegener, who was the CONTROL during one of the Griffin shifts during translunar coast, is never seen or heard from again after that shift. It's plausible to guess he was conscripted for MER duty, and I'm sure there were others.
« Last Edit: September 11, 2023, 02:01:50 pm by MadDogBV »