ApolloHoax.net
Apollo Discussions => The Reality of Apollo => Topic started by: Flookie on February 20, 2016, 08:43:39 PM
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I came across this in a newspaper forum and I have no idea how the docking mechanism did work much less what he means by "3' ringed-circles" (the hatches between the two modules?). I couldn't find information online that I could properly comprehend.
"Try using your brain and explaining how the LEM and control module managed to reconnect two 3' ringed-circles in a frictionless environment with only four directional thrusters and a computer that wasn't fast enough to help. They didn't even use a cone-type receiver like a jet would to re-fuel."
In terms of "using your brain" it seem a good idea to ask the people who would know :)
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Actually, they did use a "cone-type receiver like a jet would use to refuel". It's on the LM side, and was called the "drogue".
Check this page. Note links to illustrations.
http://www.apollosaturn.com/asnr/docking.htm
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This (http://history.NASA.gov/afj/aoh/aoh-v1-2-13-dock.pdf) should give you all the information you need.
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This (http://history.NASA.gov/afj/aoh/aoh-v1-2-13-dock.pdf) should give you all the information you need.
Hey, thank you very much for posting that. I've always wondered just how the hell the docking mechanism actually worked, beyond the bare-bones basics of it that is. I haven't read through it yet, but I already understand it better from just perusing the diagrams.
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This (http://history.NASA.gov/afj/aoh/aoh-v1-2-13-dock.pdf) should give you all the information you need.
This question is for Jay, but anyone may answer of course. During A14 when the CSM had difficulty docking, Jay indicated it was most likely ice in the ? Probe or docking ring assemblies?
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Am I right in thinking that modern docking mechanisms aren't that much different - other than the computer control?
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This (http://history.NASA.gov/afj/aoh/aoh-v1-2-13-dock.pdf) should give you all the information you need.
This question is for Jay, but anyone may answer of course. During A14 when the CSM had difficulty docking, Jay indicated it was most likely ice in the ? Probe or docking ring assemblies?
The theory was ice in the capture latches on the probe, however I believe the investigation came down in favour of contamination in the latch mechanism.
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Thanks guys. I think I can grasp the engineering :D I'm still wondering how they did the maneuvering precisely enough to get the right attitude to line up with the CM & drogue?
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Thanks guys. I think I can grasp the engineering :D I'm still wondering how they did the maneuvering precisely enough to get the right attitude to line up with the CM & drogue?
They had aimpoints on the target vehicle and sights on their own vehicle.
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Thanks guys. I think I can grasp the engineering :D I'm still wondering how they did the maneuvering precisely enough to get the right attitude to line up with the CM & drogue?
They had aimpoints on the target vehicle and sights on their own vehicle.
Not to mention lots and lots of practice ahead of time. I would think that docking two spacecraft once rendezvous is complete is objectively easier than aerial refueling.
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Thanks guys. I think I can grasp the engineering :D I'm still wondering how they did the maneuvering precisely enough to get the right attitude to line up with the CM & drogue?
They had aimpoints on the target vehicle and sights on their own vehicle.
No to mention lots and lots of practice ahead of time. I would think that docking two spacecraft once rendezvous is complete is objectively easier than aerial refueling.
For sure about that one, it would have been a rather dark day if you were orbiting the moon in the LM and unable to rendezvous and dock with your ride home.
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That is why they kept the OPS so that they could transfer via spacewalk if the docking failed.
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Thanks guys. I think I can grasp the engineering :D I'm still wondering how they did the maneuvering precisely enough to get the right attitude to line up with the CM & drogue?
They had aimpoints on the target vehicle and sights on their own vehicle.
I should have been clearer. How did they achieve the accuracy of entering the same orbit as the CM so that they were within close proximity? I'm thinking back to the original quote from someone who didn't think it could be done. I'm assuming a combination of what computing power they had, backed up by NASA's transmissions and the thrusters had sufficient finesse.
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Most of the ascent and closing with the CSM was done by a pre-programmed set of maneuvers. First, the ascent stage acheived orbit, then that orbit was matched with the CSM over several hours. They KNEW where the ascent stage and the CSM were, what their respective velocity and position were, and the radar/transponder confirmed the distance between them. Just like the supply craft which dock with ISS. It's not a one-shot deal. It's not like hitting a bullet with a bullet. It's more like two airplanes flying in formation - just without the problems caused by air. Once the vehicles were close, the rest was done by vision and manual inputs on the hand controllers.
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Am I right in thinking that modern docking mechanisms aren't that much different - other than the computer control?
Here's (https://en.wikipedia.org/wiki/Docking_and_berthing_of_spacecraft#Androgyny) an overview of various docking systems both past and in use. Many modern systems seem to be androgynous, unlike the probe and drogue systems like Apollo.
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Far as I know it was done under manual control, with the computer only in an advisory capability (aka rendezvous radar).
But I'm not sure it is appropriate to rule out the possibility of computer control due to loop speed or inability to handle the calculations. As an extremely rough approximation, the AGC had about the effective refresh rate and bit depth of the first generation Ardupilot (an AVR-micro based hobby board) and the latter was able to fly, navigate, and land a drone with clock cycles to spare.
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I should have been clearer. How did they achieve the accuracy of entering the same orbit as the CM so that they were within close proximity?
Here is a lengthy description of how they did it: http://history.nasa.gov/afj/loressay.htm
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How did they achieve the accuracy of entering the same orbit as the CM so that they were within close proximity?
They'd had practice on the Gemini missions, and on all the previous manned Apollo missions.
The orbital mechanics and laws of physics don't change between missions.
Strikes me it would be radically easier than negotiating two refuelling planes in a force 9 gale, rain, and thunderstorm .....
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Here is a lengthy description of how they did it: http://history.NASA.gov/afj/loressay.htm
And that's the simple explanation... :o I'll try to get my head around it :)
I'm used to handling misconceptions & conspiracies to do with medical & biological research. This one was beyond my knowledge and left me curious as to the finer details. Thanks for the explanations everybody.
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Strikes me it would be radically easier than negotiating two refuelling planes in a force 9 gale, rain, and thunderstorm .....
I'll stick to pulling into parking spaces ;)
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It's not easy or intuitive, but amateurs can do it, with practice, in Kerbal Space Program. Now, that's much more forgiving, plus, unlike reality, there's quicksaves, but the basic mechanics are the same.
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Gemini 11 first performed the direct ascent maneuver that Apollo used for rendezvous/docking
https://en.wikipedia.org/wiki/Gemini_11
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It's not easy or intuitive, but amateurs can do it, with practice, in Kerbal Space Program. Now, that's much more forgiving, plus, unlike reality, there's quicksaves, but the basic mechanics are the same.
The real astronauts had much practise, and some very smart people were working the problem for several years, so the chance of success was quite high.
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"Try using your brain and explaining how the LEM and control module managed to reconnect two 3' ringed-circles in a frictionless environment with only four directional thrusters and a computer that wasn't fast enough to help. They didn't even use a cone-type receiver like a jet would to re-fuel."
Don't ya just love it when someone is rubbishing the accomplishments of Mercury, Gemini and Apollo, and suggests to another party "try using your brain", yet doesn't even know that the original term, "Lunar Excursion Module" was changed to simply "Lunar Module"?
Flookie, you might like to point out to Brainbox that the correct abbreviation is LM not LEM.
Furthermore, what does Brainbox mean by "only four directional thrusters"? I thought it was 16, but could be wrong. And why does he think the computer was necessary when the final docking step could be done manually and guided by a pair of eyes and a brain?
Not to mention his nonsense about the lack of a "cone-type receiver" which has already been covered by ka9q in reply No. 1...
In terms of "using your brain" it seem a good idea to ask the people who would know :)
True -- and keep asking questions if you're not sure of something. Plenty of people here are willing to help and to be appropriately pedantic when necessary. :)
Also Flookie, welcome to ApolloHoax.
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Not to mention lots and lots of practice ahead of time. I would think that docking two spacecraft once rendezvous is complete is objectively easier than aerial refueling.
I agree.
Connecting for in-flight-refuelling is exceedingly difficult to do. It takes many hours of practice to be able to hook up first time/every time. I know this because I was given an opportunity to try it on a tech-check flight in a TA-4K Skyhawk. You have turbulence, crosswinds and vortices coming off the tanker to contend with. It was even more difficult than you might expect for us because the "tanker" wasn't a nice big stable aircraft like a KC-135, it was another A-4K Skyhawk with a refuelling pipe trailing off a centreline drop tank. I was allowed four goes and failed all four times.
Docking in space must be mere ducksoup by comparison.