Crew Dragon Docks with ISS • Hacker News Board

Re: Crew Dragon Docks with ISS

#91

Post by VLM » Sun, May 31, 2020, 4:45 PM UTC

bane wrote: post #26

starik36 wrote: post #21

Earlier quoted context omitted.

All true, however, (splitting hairs, yes), the reason FH9 can best the shuttle boosters is because they had to carry the shuttle itself, which was around 50 tons.

I wonder, as a percentage of launch vehicle, how much mass the shuttle program managed to reuse after a mission vs. the F9Heavy? It turns out not having to "shuttle" half a dozen humans up to orbit every time you want to get something up there is a good idea.

Its cheap light and easy to haul a half dozen humans home in a capsule, but its complicated and heavy to haul down immensely heavy satellites with a decent cross range such that you could land next orbit on friendly territory at all times.

Remember the shuttle "had to" be all things to all people, and the military demands ended up being VERY heavy and expensive.

At this time AFAIK nobody has the technical ability to snatch a Soviet spy sat and take it home, or haul strange and heavy (many ton) electronic warfare payloads over a target and land next orbit on NATO turf. Now, WHY you'd want to, or SHOULD you want to, are outside the bounds of this discussion, but the shuttle certainly had that kind of military stuff as a very expensive and very heavy design req.

Re: Crew Dragon Docks with ISS

#92

Post by option » Sun, May 31, 2020, 4:46 PM UTC

godzillabrennus wrote: post #16

jari_mustonen wrote: post #12

We are a small step closer inhabiting Mars. When we will, it will be the most important event in the five billion years history of our solar system. In other words, we are witnessing some pretty cool stuff.

Elon Musk will have cities on planets names after him for generations to come. The legacy he leaves will be greater than that of Ghengis Kahn, Ceasar, or Alexander the Great.

If he manages to make humans multi-planet species he’ll be the greatest man who has ever lived.

Re: Crew Dragon Docks with ISS

#93

Post by yellowapple » Sun, May 31, 2020, 4:47 PM UTC

ape4 wrote: post #87

yellowapple wrote: post #57

Earlier quoted context omitted.

Considering how long the ISS has been up there, it could be POTS or something similarly-analog. Dragon→ISS was clear, but ISS→Dragon was not, making me think that maybe there's some wire or connector in the latter direction that's shoddy (and that'd be more common for analog/POTS than digital/VOIP, where such garbling would be bidirectional and/or nothing would be heard on either end). Then again, I ain't exactly a s…

Makes sense. They just fixed the hard line

Was that the hardline or did they reroute through RF and/or "Big Loop"? I heard the loud and clear (and earlier about the cameras possibly interfering) but missed if that loud and clear was through the hardline.

Re: Crew Dragon Docks with ISS

#94

Post by nickez » Sun, May 31, 2020, 4:48 PM UTC

yellowapple wrote: post #54

stoneman24 wrote: post #33

Earlier quoted context omitted.

I had a terrible first attempt. Then discovered the same procedure, sort the rotation to 0, then minimise the translation and finally approach the dock. Head down And concentrate on the numbers. I didn’t have the KSP experience to fall back on. I wish they had added a timer as I am now trying for my fastest time.

Yeah, the live stream mentioned the ability to switch between coarse and fine controls, and that ability would be invaluable for a speed run.

You can do that by clicking in the middle of the controls.

Re: Crew Dragon Docks with ISS

#95

Post by yellowapple » Sun, May 31, 2020, 4:51 PM UTC

nickez wrote: post #94

yellowapple wrote: post #54

Earlier quoted context omitted.

Yeah, the live stream mentioned the ability to switch between coarse and fine controls, and that ability would be invaluable for a speed run.

You can do that by clicking in the middle of the controls.

Well shit. That would've been useful to know. Time for some speed-running!

Re: Crew Dragon Docks with ISS

#96

Post by jandrese » Sun, May 31, 2020, 4:54 PM UTC

elliekelly wrote: post #55

From NASA's Mission Updates: > The Crew Dragon arrived at the station’s Harmony port, docking at 10:16 a.m. EDT while the spacecraft were flying about 262 miles above the northern border of China and Mongolia. It's hard for me to wrap my brain around this. They seem so far away but 262 miles above earth is about the distance from NYC to DC which doesn't seem far at all.

There is a fantastic what if that talks about this.

https://what-if.xkcd.com/58/

Re: Crew Dragon Docks with ISS

#97

Post by gpm » Sun, May 31, 2020, 4:56 PM UTC

Kaibeezy wrote: post #2

“flew exactly like the simulators”

They did complain about the thermal camera cutting out as the thrusters fired in real life and not in the simulator at one point. Was that fixed in the later test?

Re: Crew Dragon Docks with ISS

#98

Post by ape4 » Sun, May 31, 2020, 4:56 PM UTC

yellowapple wrote: post #93

ape4 wrote: post #87

Earlier quoted context omitted.

Makes sense. They just fixed the hard line

Was that the hardline or did they reroute through RF and/or "Big Loop"? I heard the loud and clear (and earlier about the cameras possibly interfering) but missed if that loud and clear was through the hardline.

Sorry dont know. Did hear mention of big loop

Re: Crew Dragon Docks with ISS

#99

Post by fasteddie31003 » Sun, May 31, 2020, 5:07 PM UTC

hinkley wrote: post #36

I recall Elon was hoping to get an order of magnitude reduction in cost per launch, but Wikipedia claims it costs $160 million per launch versus the Soyuz price of $76 million per astronaut. That would “only” be a 3x reduction with a crew of seven, but they’ve configured for a crew of four, which is a hair under 2x. I wonder how reuse affects the math, and what they’ll be able to do to lower those prices further. Obv…

If they filled the dragon to its capacity of 7 it would be closer. I believe hearing that NASA will only use up to 4 seats.

Re: Crew Dragon Docks with ISS

#100

Post by agumonkey » Sun, May 31, 2020, 5:07 PM UTC

bane wrote: post #15

SpaceX runs basically as a giant R&D program that also happens to accomplish useful things as byproducts of its approach (with the miracle of insurance to cover costs if things get explody). Every flight is data for incremental improvement. If you think of all SpaceX has ever done was try to get to this point, with somewhere around 80 flights on the Falcon 9, but for a variety of mission buyers (NASA, USAF, Commercia…

There was an article floating recently about the death of corporate R&D .. SpaceX might be one exception (or maybe first of a new wave ?)