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21
The Reality of Apollo / Re: Apollo 8 TV question
« Last post by Count Zero on July 21, 2021, 09:51:04 PM »
Part of page 73 tackles the problem you mention:-

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...there was a great deal of difficulty in aligning the camera so as to have the earth in the center of the frame. Bill Anders would later note, "For a while they kept telling us, 'Move it up' or 'Move it down'. We kept moving it the wrong way. In space, who knows which direction is up?" Capcom guided the astronauts, who in turn moved the camera in its mounting bracket and also physically repositioned the spacecraft to achieve the required framing of the earth.

Something else that would have helped is to work out in advance the exact language to be used when giving instructions for framing the view. All terms would have to be relative to exactly where the camera is pointing "now", and "up" would mean perpendicular to the top of the camera, not to the surroundings.  So "move it up" would mean "raise the entire camera [a specified distance] but keep it pointing in the same direction." In fact, "tilt the lens up ten degrees" might have been better than "move it up", which wouldn't achieve much when it's already almost pointing at the distant earth, unless the transmitted view was partly blocked by the frame of a window or some other obstruction.

Perhaps this is why, on Apollo 11, they had a couple of post-TLI practice transmissions before the main broadcast.
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General Discussion / Re: Richard Branson
« Last post by Count Zero on July 21, 2021, 05:28:20 PM »
I saw a rant by Steve Shives about how he's salty about these flights and wants real astronauts back....

That is an absolutely brilliant analysis/summation.  May I share it (with attribution)?
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The Reality of Apollo / Re: Apollo 8 TV question
« Last post by Kiwi on July 21, 2021, 09:34:08 AM »
Fellow ApolloHoax member Dwight is probably the best person to advise you. I've had a quick scan of the relevant chapters of his book "Live TV From the Moon" and couldn't find a clear answer. Weight restrictions in the spacecraft would have had a big bearing on what accessories could be carried. Apparently pills had been cut in half to save weight, but simple wire frames at the front and back of the top or one side of the camera might have helped.

Part of page 73 tackles the problem you mention:-

Quote
...there was a great deal of difficulty in aligning the camera so as to have the earth in the center of the frame. Bill Anders would later note, "For a while they kept telling us, 'Move it up' or 'Move it down'. We kept moving it the wrong way. In space, who knows which direction is up?" Capcom guided the astronauts, who in turn moved the camera in its mounting bracket and also physically repositioned the spacecraft to achieve the required framing of the earth.

Something else that would have helped is to work out in advance the exact language to be used when giving instructions for framing the view. All terms would have to be relative to exactly where the camera is pointing "now", and "up" would mean perpendicular to the top of the camera, not to the surroundings.  So "move it up" would mean "raise the entire camera [a specified distance] but keep it pointing in the same direction." In fact, "tilt the lens up ten degrees" might have been better than "move it up", which wouldn't achieve much when it's already almost pointing at the distant earth, unless the transmitted view was partly blocked by the frame of a window or some other obstruction.
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General Discussion / Re: Richard Branson
« Last post by Zakalwe on July 21, 2021, 03:41:34 AM »
New Glenn looks impressive.

Vapourware and CGI is easy.
BO are really struggling with developing the BE-4 and are already well behind plan. ULA are allegedly very pissed that BO has failed to deliver, but they are also protecting BO to an extent. Unless they move to another engine Vulcan will be delayed.
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General Discussion / Re: Richard Branson
« Last post by Glom on July 20, 2021, 04:49:00 PM »
My concern is about the safety side of things. From what I've read other people in the industry were scathing of Branson after the accident a few years ago where a spacecraft was destroyed. I don't know whether the criticisms were valid or if the critics just didn't like their patch being invaded by a rich amateur; and if the former, whether the shortcomings have been addressed. I'll leave that to people in the know.

Don't worry. NASA, Virgin Galactic's operations are regulated by the FAA so... oh... right.

I saw a rant by Steve Shives about how he's salty about these flights and wants real astronauts back. It was a douchier echo of arguments I've heard before about how the age of the eccentric billionaire isn't inspiring the way the golden age of NASA was.

The thing is, I think this really is rose tinted nostalgia goggles. NASA was achieving the most (in human spaceflight; for the purposes of this argument, that's what I'm talking about) when it was running on unashamed willy waving. When that factor became less powerful, things got more stagnant. For the likes of Shives, NASA achieved enough for them to believe that its drive was the furthering of human endeavour, a true proto-Starfleet exploring strange new worlds, but the truth is it was never that ideal. Throughout the decades of stagnation they could hope that maybe it would be this year that the president and Congress would give NASA the support they needed to become proto-Starfleet, but this was always a forlorn hope.

That was what has Shives so miffed. The arrival of these market disruptors has forced him to face the reality that NASA was never what he wanted to believe it was.

But there is something else. Shives wants real astronauts back. He talks about how he regards them as heroes. But the age of hero astronaut was always going to be temporary. No-one thinks of the guy flying the A350 from Heathrow to JFK as a hero, even though their flight is far more of a feat than what Lindburgh did. Even an Airbus test pilot isn't regarded as a hero. Aviation is routine now, mundane. If we are to progress, that is what space is to become. Seeing Branson go to (almost) space is a kick in the teeth because it heralds the post-astronaut age. One where going to space is the realm of the ordinary guy, not the hero. Branson is an ordinary guy except for his wealth and all that wealth did was get him an earlier ticket. But the idea is that where the super rich go now, in a few years, the economically average will follow. What Shives really wants is to trap spaceflight in amber, fossilised in a state of perpetual novelty. Perpetual novelty is of course an oxymoron. And it is having to face this truth that upsets him.

Really, this is a very exciting time. Space travel is no longer at the whim of the government with a willy to wave or pork to pack in barrels. The richest men in the world aren't doing this because they want to make money. They already have it all and they didn't obtain it by crazy ventures like this. They're doing this because they think space travel is cool. The profit component is simply necessary to make it stick this time. In a way, they represent the ideal of space flight as a human endeavour more than NASA ever did. But it is not what the likes of Shives spent their childhoods imagining. Their journey to coming to terms with that has only just begun.

True, Bezos, Branson and Musk put a big share of their ego into this, but a Youtuber has no business criticising others for narcissism.
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The Reality of Apollo / Re: Apollo 13 questions
« Last post by JayUtah on July 20, 2021, 10:26:50 AM »
If the ground power was configured to 28 vdc would there have been any likely errors to an including the venting of O2 through the bent valve?

No.  The thermostat would have functioned as expected and prevented the heater from baking the tank.

Ironically the plethora of voltages used in the spacecraft and launch vehicle and the likelihood of human error in operating GSE connections was what motivated standardizing GSE DC voltage to 60 and validating the entire spacecraft to accept that voltage for direct DC connections.  It's not clear from my reading that the GSE could even have been configured to supply a lesser voltage.
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General Discussion / Re: Richard Branson
« Last post by Jeff Raven on July 20, 2021, 10:26:03 AM »
And I see now that Blue Origin has up-and-downed.

Well, congratulations to them too. At least BO's rockets are being developed with a longer trajectory in mind, compared with Virgin Galactic. New Glenn looks impressive.

*edited*  Yup. The flight went pretty smoothly. (the broadcast I watched was another story) I thought on initial (and replay) watch that the thrusters didn't fire just before landing, but they did. I'm sure the chairs are designed to handle a 16mph landing speed instead of the slower one that the thrusters provide, but it's good to see that they didn't have to. 

Looking forward to seeing and hearing the in-capsule video and audio.
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The Reality of Apollo / Re: Apollo 13 questions
« Last post by JayUtah on July 20, 2021, 10:22:22 AM »
OK. Not so much a wiring fault as wiring damage caused by the use of incorrect procedures.

Maybe not even incorrect procedures.  The procedure for removing the cryogenic oxygen tank was correct and well documented.  But it was not correctly carried out:  a bolt was left in place that, according to procedure, should have been removed.  That's a human error, not an error in the procedure.  The forklift operator who was to perform the final lift and extraction could have realized sooner that the tank was binding.  But it wasn't supposed to be binding at all, so who was at fault?  Would a more skilled operator have done better?

Once the tank had dropped two inches back onto the shelf, the correct procedure was to send it back to Beech Aircraft for inspection and requalification.  Beech's inspection revealed a damaged purge assembly.  But the purge assembly is not a flight-critical element.  It's used only on the ground during detanking, which never happens in flight.  The people who made those decisions did not consider the consequences of ad hoc procedures that might be employed later by others to compensate for the degraded purge assembly.  To a certain extent, they are allowed to assume that all correct procedures will be followed from there on out.

The 60-volt qualification test was also done at this time.  But that is an electrical test only.  The engineers determined that 60 volts DC could be applied to the various components of the tank without any operation that exceeded the flight limits, including the thermostat (in the closed position).  The thermal trip test is a different test.  The thermostat doesn't have to be energized for that test, and it was not required for the 60 VDC qualification anyway.  In hindsight we can certainly argue it should have been, so there's an example of an incorrect procedure.

A normal tank vent/purge cycle does not require the heater.  You simply connect the ground purge assembly and open the purge valve.  A technician monitors tank pressure on the ground service equipment (GSE) panel to verify when the tank has completed venting.  Then you purge with something like gaseous nitrogen or ambient air through the fill valve for a prescribed amount of time to eliminate the possibility of an oxygen concentration in the tank.  The tank is then considered "safed."  The cycle has to complete before other operations near the SM can happen, such as those that might produce sparks.  So there's some pressure (no pun intended) for it to happen according to schedule.

The decision to turn on the tank heater to speed up boil-off was approved by the relevant engineers, so by (pedantic) definition it was not an incorrect procedure.  A significant part of my day on any given day is approving variances to established procedure.  As soon as a procedure deviation bears my signature, it has just as much validity with respect to regulation as an approved standard procedure.  The engineers who signed off on this procedure had every reason to believe that it was safe to do so because the Beech engineers had qualified the tank for 60 VDC GSE operation, and the procedure did not contemplate operating the tank outside the recommended limits.  Sensibly enough, the tank temperature gauge on the GSE did not read any higher than the tank was designed to go, even when heated.  Not incorrect procedure, but maybe short-sighted.

The concept at play here is something called "tolerance buildup."  We approve decisions in engineering based on tolerances for error, safety factors, and so forth.  A tolerance buildup occurs when individual components drift toward an out-of-tolerance condition in all the same direction, so that the result is an entire system that is dangerously close to an overall tolerance violation.  At every step of the process in servicing and operating the cryogenic tank, a little step was taken toward making the tank a little less tolerant of heat and electrical conditions.  Individually, most of them were innocuous.  The only truly out-of-tolerance condition that was allowed was the runaway heater during the detanking.  That resulted in a truly intolerable condition:  uninsulated wires.  But up until then, there was just a sequence of, "Yeah, I suppose that's okay."

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So this could have gone boom at any time. Jack Swigert was just unlucky enough to be the guy who flicked the switch.

Yup.
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General Discussion / Re: Richard Branson
« Last post by Peter B on July 20, 2021, 10:06:40 AM »
And I see now that Blue Origin has up-and-downed.

Well, congratulations to them too. At least BO's rockets are being developed with a longer trajectory in mind, compared with Virgin Galactic. New Glenn looks impressive.
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The Reality of Apollo / Re: Sample bags
« Last post by Kiwi on July 20, 2021, 09:47:42 AM »
Two gems from the Apollo 16 EVAs.

To make sense of the ground elapsed times:
EVA 1 – 118:53:38 to 126:04:40
EVA 2 – 142:39:35 to 150:02:44
EVA 3 – 165:31:28 to 171:11:31

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122:47:28 Duke: Okay. This white rock that I picked up is in bag 373.

122:47:33 England: Okay, 373.

[Fendell finds Charlie at the back of the Rover. He is holding an individual sample bag with the tabs between the thumb and forefinger of either hand. He spins the bags several times around the axis formed by the stiffening wire in the top of the bag.]

122:47:39 Duke: It really works when you spin them up, Tony; it's great! (Pause)

[Duke - "It worked real good for us. The bags were like sandwich bags and had some little aluminum clips (tabs) on the end and, normally, people just folded them over and clipped them like a sandwich bag. But we found that just flipping them was quicker and then folding them in and that would lock it closed. That's what we did to every bag, if the sample wasn't so big that you...Sometimes we'd put a rock in there that was too big to do that with and couldn't get it closed at all; but we wanted to identify that rock, so we went ahead and put it in a bag so that they'd know where it was on the surface and we could identify it again. But that flipping it worked real good. I think the sample bags should have been bigger. You know, on future missions I think we ought to have bigger sample bags."]

[Muehlberger, from a 1997 e-mail message - "That technique was one that I suggested while watching them on a training exercise. Glad it worked so well!"]

[Charlie folds the tabs across the top of the bag and heads for the CDR seat. He stops near the left-rear fender and takes the CDR camera off his RCU bracket.]

Dr William R (Bill) Muehlberger, head geologist, can be seen a few times in the official Nasa movie Apollo 16: Nothing So Hidden. At about 13:22 he is snacking in a cafeteria with Jim Lovell, and at 19:22 he's in the back room with his colleagues, including Jack Schmitt, and when Young and Duke gradually get smaller on TV as they head toward House Rock he says, “And as our crew slowly...” which causes a lot of laughter because of the western movies of the 50s which so often ended with the hero(es) riding off into the sunset.

Going by Eric Jones's comment which follows, this event must be worth a look:-

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166:54:37 Young: Now, Tony, what is it you want me to do here?
[Fendell finds John at the CDR seat where he is removing a sample bag from the dispenser on his camera. During Tony's transmission that starts at 54:48, John bags the sample, spins the bag closed, and then folds the metal tabs to seal the bag. Note that he folds one tab on one side of the bag and the other tab on the opposite side. This is called "Z-ing". This may be the best video of sample bag closure in the Apollo record.]

There are also instances of sample bags being closed with the original non-spinning technique which I've yet to look up on the Spacecraft Films 6-DVD set. John Young found that a great mess could result when spinning a bag full of soil in one-sixth G.
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