Debate with hunchbacked on facebook

[smartcooky]

ah ok thanks Jason. yes the firework example is a good one. sorry abaddon I don't quite follow your point

Relative to you, the phone always keeps the same face toward you, but from the point of view of anyone watching you, the phone has rotated through 360° over the same period that it revolved about you (completed one orbit)

NITPICK/FURTHER EDUCATION

The Moon actually does not keep exactly the same face toward the earth. This is due to something called "libration"



- from Wikipedia https://en.wikipedia.org/wiki/Libration#Lunar_libration

Libration in longitude results from the eccentricity of the Moon's orbit around Earth; the Moon's rotation sometimes leads and sometimes lags its orbital position.

Libration in latitude results from a slight inclination (about 6.7 degrees) between the Moon's axis of rotation and the normal to the plane of its orbit around Earth. Its origin is analogous to how the seasons arise from Earth's revolution about the Sun.

Diurnal libration is a small daily oscillation due to the Earth's rotation, which carries an observer first to one side and then to the other side of the straight line joining Earth's and the Moon's centers, allowing the observer to look first around one side of the Moon and then around the other—because the observer is on the surface of the Earth, not at its center.

 

[smartcooky]

No, the RCS wasn't throttleable, but could be fired in very short bursts, down to 1/100th of a second. They provided both pitch, yaw and roll, and also lateral movement.

AIUI, they work in much the same way that the cold gas thrusters work on the SpaceX boosters, on (max thrust) and off. A long burst is used to completely flip the booster over in preparation for the boostback burn (and a long burst to cancel that rotation) then a series of short bursts of max thrust to adjust the reentry angle of the booster.

[Allan F]

About 15 tonnes prior to descent, and I believe the ascent stage had a mass around 2.35 tonnes after orbit insertion.

[JayUtah]

Around 27,000 pounds at DOI and around 3,500 pounds at lunar liftoff.

[benparry]

hey thanks again guys I always learn something new here lol I almost feel embarrassed when I carry on the debate back on FB lol

[Allan F]

Around 27,000 pounds at DOI and around 3,500 pounds at lunar liftoff.

The numbers I can find talk about 2150 kg at rendezvous. And 4700 kg at lunar liftoff for the ascent stage.

Otherwise, the empty ascent stage with astronauts and samples would mass 800 kg on its own.

[JayUtah]

Around 27,000 pounds at DOI and around 3,500 pounds at lunar liftoff.

The numbers I can find talk about 2150 kg at rendezvous. And 4700 kg at lunar liftoff for the ascent stage.

Otherwise, the empty ascent stage with astronauts and samples would mass 800 kg on its own.

Yes, table 1 here http://www.clavius.org/techexhaust.html gives the figures for LM-6 at touchdown on the lunar surface.  I knew I had these laying around somewhere.

[Peter B]

Hi all

After wrongly thinking Pascal had retired from Facebook he is back and debating me in a group. Although he wasn't the original poster he has had some thoughts. I think the answer is simple do you guys have any thoughts

It'd be interesting to find out why Pascal thinks that image is genuine, given the ease with which its (un)reality can be checked.

...each pitch or roll command activates two vertical thrusters directly opposed to each other, so pushing in opposite directions, which means that they cancel their mutual effects (and I remind you they were not throttleable); how could this work?

Again, it'd be interesting to find out why Pascal thinks this was the case. I mean (i) illustrations have always been available of the use of the thrusters showing how they were fired on opposite sides of the Service Module to rotate the spacecraft, and (ii) using thrusters this way to rotate a spacecraft was hardly new to Apollo - they'd been used on both manned and unmanned spacecraft for years before Apollo. I mean, even as a hoax hypothesis it doesn't make sense.

[bknight]

Hi all

After wrongly thinking Pascal had retired from Facebook he is back and debating me in a group. Although he wasn't the original poster he has had some thoughts. I think the answer is simple do you guys have any thoughts

A couple of information points, could you post a link to the FB page so I don't have to manually try to find it?

Did he link one of his videos in the FB page?, if so please provide that link also.

[benparry]

hey bknight

as I say the original post wasn't his regarding the actual photo but the stuff about thrusters were.

sure the link to the thread is here

https://www.facebook.com/groups/2214776597/permalink/10156507244731598/?comment_id=10156507755111598&reply_comment_id=10156509910421598&notif_id=1529161091821516&notif_t=group_comment

[bknight]

hey bknight

as I say the original post wasn't his regarding the actual photo but the stuff about thrusters were.

sure the link to the thread is here

https://www.facebook.com/groups/2214776597/permalink/10156507244731598/?comment_id=10156507755111598&reply_comment_id=10156509910421598&notif_id=1529161091821516&notif_t=group_comment

Thanks, I didn't see a link to any of his videos, so it would be next to impossible to go back and see where he flubbed.

[benparry]

hey bknight no his videos I believe are on his youtube channel. I think this is the link for that.

https://www.youtube.com/user/hunchbacked

[bknight]

That video isn't valid.  I did search hunchy's site and found a couple of videos that deal with LM's RCS system.
ApolloWasReal took him to task as he(ApolloWasReal) loved to correct him and make him look stupid.  Hunch has an aerospace engineering degree, but he pretends to know a lot about the electronics of Apollo, but unfortunately for him he grew up in the world of integrated circuits not the rather primitive 60's systems.  Although I'm not an electronics engineer, those were probably state of the art in the 60's, but not by todays circuitry.  I left a couple of comments to other posters who follow mimic his stupidness.

ETA videos I found

And here is one that mentions the RCS system of the SM

[benparry]

oh there is no doubt in my mind that he is an idiot lol he had a video called Apollo 11 bullshit in which he clearly states that buz aldrin salutes the flag with 1 hand when quite clearly he does it with other. he was trying to claim the video and photo didn't match. anybody with decent eyesight could see he was wrong but he wouldn't have it

[JayUtah]

Although I'm not an electronics engineer, those were probably state of the art in the 60's, but not by todays circuitry.

Some of the control systems in the CM and elsewhere weren't state of the art even by 60s standards.  Some like the Earth Landing System were relay-logic elements that had the advantage of decades of design and operation experience behind them.  The engineers who designed them had a great deal of confidence in them.  In aerospace, "new" generally means "untried."  For a while, we had a rule that an IC-type CPU could not be included in a design until it had accumulated at least 10 years of operational record.  This means it's ten years behind the curve, but by that time it is solid, reliable, and generally less buggy.  That's more desirable than faster processing speed or greater capacity.

But the lesson is still clear.  Expertise in modern systems doesn't translate to expertise in older systems.  They aren't just the same designs made with older parts.  Often they're entirely different ways of doing things, and if you don't have specific experience in them you can't be considered an expert.  Nor do you get to say that they can't possibly work just because they work differently than what you're used to.