221–230 of 475 posts
What is coming into view from the top center at 08:26:25 [0], right after the commentator says, "the weather conditions remain go"? It stays visible for more than seven minutes before disappearing behind the horizon. [0] https://youtu.be/X9Miy8ngusQ?t=30382
Earlier quoted context omitted.
My friends and I have been deriving much amusement from the comms issues. We can fly people around the moon, talk with them, send back high res video, but talk to the boat that’s close enough to swim to? Forget about it! Note: next time, pack a walkie talkie. ;-)
They missed the chance to reply "Main screen turn on."
Can somebody help me understand why this does a water landing, like the old Apollo missions, instead of like the space shuttle that lands like a plane?
Earlier quoted context omitted.
>Buoyancy is an easier equation to solve than lift. That's a snappy one-liner but it doesn't address the real concerns. First of all, subsonic lift is well understood and has been for decades. The answer is much more mundane: The Artemis mission profile does not require payload doors that open, no Canadarm, no requirement to service, launch, and/or capture satellites in orbit, and so like good engineers they designed…
> subsonic lift is well understood and has been for decades I said easy. Not well understood. I can fly planes. It’s hard, and has limited room for fucking up. (It’s also hyperbole to suggest we understand lift. We don’t.) Piloting a boat is easier and more forgiving. Hence, splashdown. You don’t need direction. You don’t need lift. Parachute physics is a backbreaker, but it’s symmetrical. Same for splash.
I'm also a pilot (CFI). My day job is space operations. And I can tell you've had too many hangar arguments about how wings work.
Pilots don't understand lift. Aero engineers understand it just fine.
Earlier quoted context omitted.
> subsonic lift is well understood and has been for decades I said easy. Not well understood. I can fly planes. It’s hard, and has limited room for fucking up. (It’s also hyperbole to suggest we understand lift. We don’t.) Piloting a boat is easier and more forgiving. Hence, splashdown. You don’t need direction. You don’t need lift. Parachute physics is a backbreaker, but it’s symmetrical. Same for splash.
>Piloting a boat is easier and more forgiving. Hence, splashdown. At no point were the astronauts piloting a boat. The reasons they splash down into the ocean has nothing to do with buoyancy being easier to solve, and even less to do with the ease of piloting a boat. >It’s also hyperbole to suggest we understand lift. We don’t. Maybe you personally do not understand lift, but "we" do in fact understand it. Please edu…
Earlier quoted context omitted.
> Artemis acceptable crew mortality rate is 1 in 30. This seems insane to me. That X decades later we accept, with all our advancements in tech, a weaker system than ever before. That if we send 30 people we _accept_ that one is possible to die. That's the starting point? That's what we document as acceptable?
Yes, and the memories of Apollo are made rosy by hagiography. I even wrote an entire thing to explain why, https://1517.substack.com/p/1-in-30-artemis-greatness-and-ri... (yeah, shameless plug, sorry - it's more for the citations than not. You can read the standards and reports I've linked to) But if I'm allowed to repeat myself from elsewhere in the thread and the meat of the above thing, It's physically not possibl…
One launch a year is not even close to what we can manage with our current technology, to the point where the scope is too small to be legitimately worth doing.
Its not solely a matter of energy; its about opportunity for learning. The current scale is too small to be worth doing at all.
If it was a program of something like >50 payloads over a decade, that gives enough opportunity for refinement, in cost, safety, and scale manufacture methods to actually see something new.
Earlier quoted context omitted.
Nice article, although I'm not so sure about this part: > There’s a reason why there wasn’t an Apollo 18, or 19 and 20. Even though funding had been secured, an executive decision was made to kill the program early, because LoC was inevitable. Was funding really secure? I believe that was the main sticking point; a quick search [0] seems to confirm this, and the John Young quote below backs it up: "Even if they’d had…
> one more known source of risk to eliminate. How could they have eliminated that risk?
- They replaced the specific foam insulation that struck Columbia with external heaters, and redesigned other areas where foam was necessary to ensure greater structural stability + minimize damage to the shuttle in case of breakage. They also began more thorough inspection of any heat shield panels that would be reused between missions
- They added various cameras, both on the shuttle and on the ground, to monitor the heat shield throughout launch, plus accelerometers and temperature sensors. Also, the heat shield was checked manually on every mission once in orbit for damage, both with an extension to the Canadarm, and with ISS cameras when possible (a funky maneuver [0] where they would do a backflip to flash the shuttle's belly at the ISS for it to take high res pictures)
- Every mission from then on had a backup plan in case the shuttle wasn't in a state to return to Earth (this wasn't really the case before then, which is kinda wild). Another shuttle was always ready to launch, with a new configuration of seats to allow for sufficient crew space
- They sent up equipment and materials for repairs in space with every launch, though admittedly the usefulness of that was dubious and the repair kits were never used
Perhaps 'eliminate' was too strong a word, but there's no reason these precautions couldn't or shouldn't have been taken before it resulted in deaths and the loss of a spacecraft. (well, other than the aforementioned funding/politics/organizational failure)
I noticed a delay between video and audio - the announcer on the NASA official live broadcast said splashdown before the the capsule splashed down on video. Was it intentional (in case something happened)? Also, what were these puffs on thermal camera after the main chutes were deployed? https://www.youtube.com/live/m3kR2KK8TEs
My suspicion was they were burning excess propellant, rather than attitude adjustment while under the parachutes. Though who knows how much propellant remained. It could be quite a bit more than it appears was used.