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3 hours ago, StrandedonEarth said:

Having experienced a burst hydraulic line on a forklift in a freezer, hydraulic fluid not intended for extreme cold will become the consistency of creamed honey in extreme cold. Hard to say if they would use specialized hydraulic fluid. They may not think it would be exposed to extreme cold for long enough, but there are cryogenics on board, so they may decide to err on the side of caution (a lesson learned the hard way many times by rocket engineers....)

"Cryogenics on board" meaning the booster is >99% by mass of either cryogenic oxygen or kerosene cooled to cryogenic temperatures?  Well during launch.  During landing the ratio is far, far, less.

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22 minutes ago, magnemoe said:

Now this raises the issue on no abort system for manned starship. The primary issue is not launch even if both Falcon 9 fails was upper stage but landings and even that this would probably been an walk away landing on ground as they missed by 1-300 meters. 
That is for going to orbit, who is still an extreme sport. 
For P2P well starship probably need to be proven to be 1000 times safer than falcon 9 to start getting considered for approval as an airliner. 

For freight, well we have far more abort modes than the shuttle and you can add an kick stage to the 100 ton payload capacity. 
Hint an Falcon 9 second stage is 100 ton :), launch cost will be a bit cheaper than falcon 9.
Yes that will be like selling 100$ bills for 10$.

I'm not sure what you want the abort to do.  In this specific case, the passengers would only have to survive Starship falling over after the "soft landing", and after that it would be similar to landing on the Hudson.  And while the craft *did* abort (to a safe mode that wouldn't put a hole in the barge), I'm not sure what type of abort system you could have on the booster.  Has *anyone* created a *landing* abort system?  Either Soyuz, Shuttle, or otherwise?

Just now, StrandedonEarth said:

Meaning there is some super-cold stuff around that may (or may not) contribute to cooling the hydraulic reservoir.

Yeah, but I was pointing out that it wasn't just "around", it was inescapable.

Edited by wumpus
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Well today was an abject failure! Didn’t catch the fairings, throwing away the upper stage and dunking the first stage into the drink. Totally rubbish apart from completing the primary mission.

 

 

lol it’s mad to even think about that never mind write it! 

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3 hours ago, lajoswinkler said:

As long as it flows and has negligible compressibility in working range, it's ok for hydraulics.

There are other issues. For instance, most airplanes use Skydrol, because it won't turn into a flamethrower if a pressurized jet of it encounters an ignition source. (But it has an unfortunate tendency to corrode hot metal and it's irritating to human skin.)

2 hours ago, magnemoe said:

Now this raises the issue on no abort system for manned starship.

Yeah, I was thinking of that this morning too. I mean, economically it's still really impressive if only 1 of 10 boosters fails to land safely, but if 1 of 10 crewed spacecraft failed to land safely it would be something entirely different.

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Yeah, I'm not convinced about propulsive landing for humans.

They could switch the Earth landing variants for designs that look like some of the early Shuttle concepts, instead, everything else being identical:

triaml.jpg

(wings swing out)

NASM-A19760781000_PS01.jpg?itok=ZuFT-7AA

(same deal, folding wings.)

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Reminds me of one of their very early flights (possibly Falcon 1) where the launch was delayed due to cracks in the upper stage engine bell. The solution was to cut off the cracked part and launch the next day.

I imagine they will be looking at this rather carefully and redesigning as appropriate, but in the meantime - for a test vehicle - it’s great to see them just buffing out the dents and moving on, rather than going back to the drawing board straightaway.

Edited by KSK
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When is the second stage deorbit burn scheduled for? Asking because I just saw some pulsating flashes on the horizon, used Heavens Above to look up what's there and it showed me Falcon 9 Deb. Was I lucky or was it just a plane?

Edited by Wjolcz
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8 minutes ago, Wjolcz said:

When is the second stage deorbit burn scheduled for? Asking because I just saw some pulsating flashes on the horizon, used Heavens Above to look up what's there and it showed me Falcon 9 Deb. Was I lucky or was it just a plane?

Think it deorbit after just a couple orbits maximum. 
The one time they had it up for 4 hours was because they wanted to do some tests, probably simulating an GTO opperations. 
An GTO run deorbit late as it Ap will be at 36.000 km 

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Interesting... apparently the mission will not go to the ISS, instead it’ll be a 5-day free flier with a peak altitude “3x” higher than the ISS :o, providing views not seen since Gemini/Apollo. Up to 4 people, 2021-22 timeframe, so Dragon 2 will have plenty of flights under its space-belt.

Your move, Jeff. :sticktongue:

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9 minutes ago, CatastrophicFailure said:

Interesting... apparently the mission will not go to the ISS, instead it’ll be a 5-day free flier with a peak altitude “3x” higher than the ISS :o, providing views not seen since Gemini/Apollo. Up to 4 people, 2021-22 timeframe, so Dragon 2 will have plenty of flights under its space-belt.

Your move, Jeff. :sticktongue:

That is much better, honestlly- the smaller the Earth appears out the window, the more awe-inspiring and life-changing the experience. The more powerful the overview effect. The more clear our tiny place in the universe becomes.

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17 minutes ago, ThatGuyWithALongUsername said:

That is much better, honestlly- the smaller the Earth appears out the window, the more awe-inspiring and life-changing the experience. The more powerful the overview effect. The more clear our tiny place in the universe becomes.

...and the fewer regulations need to be hurdled by not involving the ISS partners... <_<

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5 minutes ago, CatastrophicFailure said:

...and the fewer regulations need to be hurdled by not involving the ISS partners... <_<

 ...yeah, probably that too <_<

 

The whole "break a record" thing is great for marketing, too

Edited by ThatGuyWithALongUsername
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2 hours ago, CatastrophicFailure said:

 

Interesting... apparently the mission will not go to the ISS, instead it’ll be a 5-day free flier with a peak altitude “3x” higher than the ISS :o, providing views not seen since Gemini/Apollo. Up to 4 people, 2021-22 timeframe, so Dragon 2 will have plenty of flights under its space-belt.

Your move, Jeff. :sticktongue:

What is the radiation exposure there?

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20 minutes ago, mikegarrison said:

What is the radiation exposure there?

That's what, ~1000 - 1200 km? Not bad, maybe slightly higher than ISS, but we're talking 4-5 days.

Worse would be sharing a cabin with 3 strangers for 4 days, it's like a small jail cell with a cool view, and a toilet in the middle of the room. And 50% of you will be barfing.

Edited by tater
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Even though I will probably never fly on one of those (unless Starship somehow gets super cheap) I think it's very cool. Also, if the overview effect is real then we might see some very positive things happen done by people who can actually afford to make them happen.

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8 minutes ago, tater said:

That's what, ~1000 - 1200 km? Not bad, maybe slightly higher than ISS, but we're talking 4-5 days.

Worse would be sharing a cabin with 3 strangers for 4 days, it's like a small jail cell with a cool view, and a toilet in the middle of the room. And 50% of you will be barfing.

I imagine it's like owning a yacht. If you can afford a small yacht, you can probably afford a big one. If you can afford one seat in a space capsule, you can probably afford the rest of them too, which would mean that at least the people you are sharing your bodily functions with wouldn't be strangers.

Edited by mikegarrison
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12 minutes ago, Wjolcz said:

Even though I will probably never fly on one of those (unless Starship somehow gets super cheap) I think it's very cool. Also, if the overview effect is real then we might see some very positive things happen done by people who can actually afford to make them happen.

I could see Starship making LEO trips like a cruise liner with private cabins and 1-2 week stays.  Perhaps a few dozen patrons plus catering/service staff.

Should be a lot less expensive than the F9 trips, and more luxurious too. 

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