yea this seemed like simple PID control to me, nothing impressive yawn
Starship Flight 5: Launch and booster catch [video]
961–970 of 1001 posts
Re: Starship Flight 5: Launch and booster catch [video]
#962I think that catching a grain silo in mid air that fell in a semi-controlled way from effin low earth orbit is undeniably incredible. SpaceX continues to blow me away with these unbelievably lofty ideas. I remember seeing their "grasshopper" flights years ago and they blew it up because they couldn't land it at the time, who knew within a few years they'd be doing this.
I think they still have "Grasshopper" (the custom test unit) sat outside at McGregor, it was F9R Dev1 (a modified F9 booster) that they had to destruct after one of the engines failed mid-hop.
They were originally going to do high-altitude tests with an "F9 dev2" (similar to some of the early starship test launches) - but they gave up and just did some testing with real landing Falcon 9s instead.
Re: Starship Flight 5: Launch and booster catch [video]
#963Earlier quoted context omitted.
Yes, we should probably assume that the SpaceX engineers have considered all of the risks HN readers are able to come up with in a few hours. And that they have evaluated alternatives like the added weight etc of having foldable legs on the booster. The catchzilla solution is an example of their amazing ability to think out of the box. This solution, and things like the rapid evolution of the Raptor engine (see pictu…
But did they consider a giant spider web?
We can probably assume yes:
https://www.youtube.com/watch?v=qz7Eb8WiiWA
Re: Starship Flight 5: Launch and booster catch [video]
#964Earlier quoted context omitted.
> The detonation at the end was pretty spectacular too, but I suspect that structurally the tanks failed as the rocket hit the water vs anything that was an engineering failure. It's possible that SpaceX programed the AFTS to trigger some time after the rocket touched down in the water. Just to make sure that it completely submerges quickly. > I can easily imagine that flight 6 will be nominal end to end without any…
> It's possible that SpaceX programed the AFTS to trigger some time after the rocket touched down in the water. Just to make sure that it completely submerges quickly. The SpaceX host on the stream said that they were going to try and touch it down on the water at more of an angle than the previous flight to attempt to get it to survive the initial splash-down so they could get some more data and video footage. Obvio…
Yeah, I don't think SpaceX planned for a RUD on tip-over (even if they did anticipate it).
I think they've towed stuff in the sea before so I would have thought that'd be their preference if it were possible.
Re: Starship Flight 5: Launch and booster catch [video]
#965Pretty impressive. The engineering team at SpaceX is really something. Some thoughts; The 'chopsticks catch' was amazing to watch. Seems like it adds a lot of risk and clearly the booster needs additional fire suppression systems :-) perhaps the tower could mount something that sprays the booster like the barges have for the F9 boosters. The heatshield held out for a much longer time, the asymmetric heating on the fl…
They showed 4 streams at once during some of the reentry. One view of each control surface. They may have had still more views but just that 4 was a first.
Wait, that was 5 views no? Facing four fins, plus one fin from the front.
Re: Starship Flight 5: Launch and booster catch [video]
#966Earlier quoted context omitted.
> It's possible that SpaceX programed the AFTS to trigger some time after the rocket touched down in the water. Just to make sure that it completely submerges quickly. The SpaceX host on the stream said that they were going to try and touch it down on the water at more of an angle than the previous flight to attempt to get it to survive the initial splash-down so they could get some more data and video footage. Obvio…
Yeah, I don't think SpaceX planned for a RUD on tip-over (even if they did anticipate it). I think they've towed stuff in the sea before so I would have thought that'd be their preference if it were possible.
Yeah. It wasn't planned, but was a likely outcome.
I'm not sure if they would have actually attempted to tow this one somewhere given its location in the Indian Ocean, but they might have taken the opportunity to do some inspections before sinking it.
Re: Starship Flight 5: Launch and booster catch [video]
#967Pretty impressive. The engineering team at SpaceX is really something. Some thoughts; The 'chopsticks catch' was amazing to watch. Seems like it adds a lot of risk and clearly the booster needs additional fire suppression systems :-) perhaps the tower could mount something that sprays the booster like the barges have for the F9 boosters. The heatshield held out for a much longer time, the asymmetric heating on the fl…
I'm wondering if they'll be using the vertical equivalent of arresting gear on aircraft carriers[0]. See when fighter jets land on aircraft carriers? There's a cable that decelerates them. That, but for vertical landing. The way these chopsticks are set forces the booster into a dangerous, snake like maneuver (a SnakeX maneuver) at the last second from a vertical setting, to get into the chopsticks. This maneuver is…
That's how the Chinese are planning to do it:
Re: Starship Flight 5: Launch and booster catch [video]
#968Very difficult to enjoy with all the screaming
For some reason, the spacex screams sound nightmarishly terrifying to me.
Re: Starship Flight 5: Launch and booster catch [video]
#969I went to follow this on the SpaceX YouTube channel since it is usually closer to real time. It seems someone hijacked and played a video of the previous launch. Just as we got to launch time it cut to a fake badly dubbed speech by Elon Musk going on about Bitcoin, with a handy QR code. This was a bit confusing but since it was 10 minutes in advance I managed to switch to another channel. Still amazing, even if the v…
You need to look closely at the channel name in a URL and not just the branding signals on the page itself (logos, "presentation name"), etc. What you'll find is that the on-page channel name can be made pretty much anything as well as logos, banner's etc. But when you look at a URL that leads to the channel page, it's not the same and it doesn't have the verification check. There is a real SpaceX channel: https://ww…
This was on the YouTube appleTV app
Re: Starship Flight 5: Launch and booster catch [video]
#970Earlier quoted context omitted.
MIMO and nonlinear control theories are probably some of the hardest topics in all of engineering. SpaceX control system also has to compensate for the fuel moving inside their rockets so the control algorithms probably involve some kind of fast numerical fluid simulation. Another interesting thing SpaceX is doing is to use consumer-grade chips in triple redundancy configurations instead of using $100,000+ radiation-…
Reliability is not based on a system that cannot fail. It is based on a system that can survive failure.
A system (whole) that can survive the failure of (some of the) individual parts. Up to a limit.