Author Topic: Questions about suit to suit comms and procedures for landings far off vertical  (Read 5789 times)

Offline Allan F

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I was wondering about the suit-to-suit comms system. As I understand it, the LMPs suit voice/telemetry radio was relayed through the commander's suit to the LM or LRV before being transmitted to Earth. If that is correct, then what was the idea behind it? Wouldn't it be simpler to have both suits transmit directly to the LM/LRV for retransmission to Earth? Would they need two separate radios on the LM/LRV for allowing both suits to talk at the same time?

Also, were there any way to right the LM, if they had happened to land with one foot in a divot, and another foot elevated, so they were outside the 15 degrees from vertical, the ascent stage were able to safely handle?

Well, it is like this: The truth doesn't need insults. Insults are the refuge of a darkened mind, a mind that refuses to open and see. Foul language can't outcompete knowledge. And knowledge is the result of education. Education is the result of the wish to know more, not less.

Offline smartcooky

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Dwayne would be the one to ask about that, but as I understand it, the suit comms were operated in duplex mode which mean that two frequencies (we'll call then F1 and F2) were used.
Voice transmissions from the LM to the EV crewmen were on F1, and voice and EMU-data transmissions from the EV crewmen to the LM were on F2.

Interesting point to note is that the ham radio guy (Larry Baysinger, W4EJA) who picked up the lunar tramissions from A11, was receiving the suit radios directly (as evidenced by the absence of quindar tones)

https://soundcloud.com/shannon-hall4/apollo-11-recording
If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.

Offline Allan F

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Yes, that was some feat, picking up milliwatt transmissions from that distance.
Well, it is like this: The truth doesn't need insults. Insults are the refuge of a darkened mind, a mind that refuses to open and see. Foul language can't outcompete knowledge. And knowledge is the result of education. Education is the result of the wish to know more, not less.

Offline smartcooky

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Dwayne would be the one to ask about that..

Sorry, that should be Dwight....... Dwight Steven-Boniecki
If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.

Offline bknight

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Dwayne would be the one to ask about that..

Sorry, that should be Dwight....... Dwight Steven-Boniecki

Another great source would be ka9q, if he is still around.
Truth needs no defense.  Nobody can take those footsteps I made on the surface of the moon away from me.
Eugene Cernan

Offline smartcooky

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Dwayne would be the one to ask about that..

Sorry, that should be Dwight....... Dwight Steven-Boniecki

Another great source would be ka9q, if he is still around.
I hadn't thought of him, but yes

I think Phil is still around. His website was last updated Sept 22.
If you're not a scientist but you think you've destroyed the foundation of a vast scientific edifice with 10 minutes of Googling, you might want to consider the possibility that you're wrong.

Offline dandypanty

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I never thought about "what if the LM had actually tipped over". Surely there was some talk or plan if this happened? I know a great deal of engineering went into those struts to decrease the risk but was there any documented plan to use leverage or some such tools or equipment to tip it upright? I can imagine a few ideas to tip it back with the help of the LRV but without attaching a chain to the CSM, A11, 12, 13, and 14 seem screwed.

Offline Peter B

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I never thought about "what if the LM had actually tipped over". Surely there was some talk or plan if this happened? I know a great deal of engineering went into those struts to decrease the risk but was there any documented plan to use leverage or some such tools or equipment to tip it upright? I can imagine a few ideas to tip it back with the help of the LRV but without attaching a chain to the CSM, A11, 12, 13, and 14 seem screwed.

My (completely unqualified) opinion is that they wouldn't have bothered to develop any plans, on the grounds that any situation which tipped the LM would have either killed the crew or rendered the LM unusable, even in the Moon's low gravity.

Offline Zakalwe

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Also, were there any way to right the LM, if they had happened to land with one foot in a divot, and another foot elevated, so they were outside the 15 degrees from vertical, the ascent stage were able to safely handle?


IIRC, the ascent stage could apparently do a FITH abort up to 70 degrees. I doubt that there would be any need to right the module because they may have done a post-landing abort if the module was tipped outside the 12 degree limits.
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