History, Politics And Current Affairs

You gotta admit, that stack holding together while doing doughnuts at 1,000 MPH is pretty impressive.

Another picture of the damage to the pad.

Supposedly the concrete pilings supporting the launch stand are sunk 100 feet plus into the Earth.

Poohbah wrote: ↑Fri Apr 21, 2023 4:42 pm You gotta admit, that stack holding together while doing doughnuts at 1,000 MPH is pretty impressive.

I saw the video for the first time this afternoon, the whole launch was hugely impressive.

I’m reading on Twitter that Musk overruled his engineers on launch timing and design of both the vehicle and launchpad. Also, that the RUD may be related to FOD from the launchpad hitting the rocket.

Does sound very Elon “I’m not as smart as I think I am” Musk. I’m also not convinced that having something like 30 engines is a good idea.

It depends, how many can they lose and when to Abort to Orbit? How many do they need to get high enough to Return to Launch site?

While the plumbing is complex, have a bunch of less power engines might allow for better margins.

One nice thing about being at JSC, I can least appear I know what questions to ask.

Musk:

3 months ago, we started building a massive water-cooled, steel plate to go under the launch mount.

Wasn’t ready in time & we wrongly thought, based on static fire data, that Fondag would make it through 1 launch.

Looks like we can be ready to launch again in 1 to 2 months.

jemhouston wrote: ↑Sat Apr 22, 2023 1:46 am It depends, how many can they lose and when to Abort to Orbit? How many do they need to get high enough to Return to Launch site?

While the plumbing is complex, have a bunch of less power engines might allow for better margins.

One nice thing about being at JSC, I can least appear I know what questions to ask.

They had six out on this flight. I think it depends on when. They lose them and where.

Kunkmiester wrote: ↑Sat Apr 22, 2023 2:35 am

jemhouston wrote: ↑Sat Apr 22, 2023 1:46 am It depends, how many can they lose and when to Abort to Orbit? How many do they need to get high enough to Return to Launch site?

While the plumbing is complex, have a bunch of less power engines might allow for better margins.

One nice thing about being at JSC, I can least appear I know what questions to ask.

They had six out on this flight. I think it depends on when. They lose them and where.

They lost two of the gimbaling engines in the center.

Abort moods from the Shuttle Issue

RTLS - Return to Launch Site - Probably the most dangerous since you need to a 180 while fast and low.

TAL - Transoceanic abort landing - Landing somewhere in Africa, Western Europe or the Atlantic Ocean (at Lajes Field in the Azores)

AOA - One orbit landing at Edwards or back at KSC

ATO - Abort to Orbit. Different orbit but usable. They did during STS-51-F.

https://en.wikipedia.org/wiki/Space_Shuttle_abort_modes

I'm not sure what SpaceX uses

Micael wrote: ↑Sat Apr 22, 2023 2:09 am Musk:

Wasn’t ready in time & we wrongly thought, based on static fire data, that Fondag would make it through 1 launch.

By "we", does he me "I wrongly thought"? SpaceX engineers thought that somehow they'd be okay when experience from launching rockets suggests otherwise? Either the engineers at SpaceX are not as good as we've been led to believe, or Musk is telling porky pies.

Bernard Woolley wrote: ↑Sat Apr 22, 2023 12:04 pm

Micael wrote: ↑Sat Apr 22, 2023 2:09 am Musk:

Wasn’t ready in time & we wrongly thought, based on static fire data, that Fondag would make it through 1 launch.

By "we", does he me "I wrongly thought"? SpaceX engineers thought that somehow they'd be okay when experience from launching rockets suggests otherwise? Either the engineers at SpaceX are not as good as we've been led to believe, or Musk is telling porky pies.

The royal “we”

I thought so. My guess is that 'Super Genius' Musk overrode the engineers.

Found this on UK Space Art site I visit. http://www.space-art.co.uk/image.php?ga ... -%20V2.jpg

jemhouston wrote: ↑Sat Apr 22, 2023 10:55 am Abort moods from the Shuttle Issue

RTLS - Return to Launch Site - Probably the most dangerous since you need to a 180 while fast and low.

TAL - Transoceanic abort landing - Landing somewhere in Africa, Western Europe or the Atlantic Ocean (at Lajes Field in the Azores)

AOA - One orbit landing at Edwards or back at KSC

ATO - Abort to Orbit. Different orbit but usable. They did during STS-51-F.

https://en.wikipedia.org/wiki/Space_Shuttle_abort_modes

I'm not sure what SpaceX uses

I believe astronaut John Young mentioned that he didn't wish to commit suicide when it was suggested that the first shuttle flight be an RTLS test.

On the STS-51F when they lost the one engine they overrode the computers to force them to keep the remaining two running no matter what.

With the TAL I guess there could be coffin corners depending on the shuttle load, trajectory, if they lost 1 or 2 engines, and when it happens. Coffin being they won't make it across the pond. Shuttles couldn't ditch so I gather the sites had plenty of air rescue parajumpers on hand.

Anything other than Abort to Orbit was filled with risks. There was abort to a site on US East Coast North of Florida.

jemhouston wrote: ↑Sun Apr 23, 2023 11:59 pm Anything other than Abort to Orbit was filled with risks. There was abort to a site on US East Coast North of Florida.

Lakenheath too.

A Shuttle coming in over the Heathrow & Gatwick approaches (and central London) might have been… interesting!

Craiglxviii wrote: ↑Mon Apr 24, 2023 9:51 am

jemhouston wrote: ↑Sun Apr 23, 2023 11:59 pm Anything other than Abort to Orbit was filled with risks. There was abort to a site on US East Coast North of Florida.

Lakenheath too.

A Shuttle coming in over the Heathrow & Gatwick approaches (and central London) might have been… interesting!

https://en.wikipedia.org/wiki/List_of_S ... ding_sites

One of the abort sites for Vandenberg launches was Easter Island. NASA & the USAF forgot to check the place out before naming it I gather. The runway was not long enough for the 747 transport aircraft to land and then figure how to lift the shuttle on top of it. I think they also forgot to ask the Chilian government if they could do it in the first place.

Oh and I forgot.... The shuttle carrier didn't have enough range so adding inflight refueling was thought about.

Bernard Woolley wrote: ↑Sat Apr 22, 2023 12:04 pm

Micael wrote: ↑Sat Apr 22, 2023 2:09 am Musk:

Wasn’t ready in time & we wrongly thought, based on static fire data, that Fondag would make it through 1 launch.

By "we", does he me "I wrongly thought"? SpaceX engineers thought that somehow they'd be okay when experience from launching rockets suggests otherwise? Either the engineers at SpaceX are not as good as we've been led to believe, or Musk is telling porky pies.

SpaceX has a lot of young talent willing to work Musk’s hours, but they also shed a lot of employees who tire of that.

So it is plausible the engineers lack the experience to go “hey, wait a minute” - especially if there’s lots of turnover.

Johnnie Lyle wrote: ↑Mon Apr 24, 2023 10:55 pm

Bernard Woolley wrote: ↑Sat Apr 22, 2023 12:04 pm

Micael wrote: ↑Sat Apr 22, 2023 2:09 am Musk:

By "we", does he me "I wrongly thought"? SpaceX engineers thought that somehow they'd be okay when experience from launching rockets suggests otherwise? Either the engineers at SpaceX are not as good as we've been led to believe, or Musk is telling porky pies.

SpaceX has a lot of young talent willing to work Musk’s hours, but they also shed a lot of employees who tire of that.

So it is plausible the engineers lack the experience to go “hey, wait a minute” - especially if there’s lots of turnover.

There's probably at least some truth to that. I have a friend at another New Space (TM) company and there's a lot of "what do those geezers in legacy aerospace know?" going on there. Heck, even at my employer we're still dealing with the ramifications of hiring too many junior and inexperienced folks to do our new designs 15 years ago.

Of course, there's also the golden rule playing out (he who has the gold, makes the rules). When it comes down to decisions Musk basically gets to make the decisions and get what he wants because he's paying for it all.

I view the damage to the launch site as somewhat of an own goal--even Musk admitted a while back that "it might turn out to be a mistake" to not fit deflectors, deluge, etc.--but I think at least on the ship end of things it was probably a pretty good and useful test. Too many people are looking at it like a final test of a final design, but this isn't too much beyond the blowing up of rocket engines that every manufacturer goes through, just at the whole vehicle level vs. the component level.