** The Official Space Flight Thread - The Space Station and Beyond **

[Armageus]

Will it have flame diverters this time?

Not in the traditional big concrete trench sense, that some are adamant they need.

Instead they are having a big upside down steel showerhead to spray water upwards (booster bidet )

Maybe if they’d not rushed it the first time they wouldn’t have to be doing it a second time…

And not challenge any of the decisions made (and largely unchanged) since the 60s, blindly accepting that as the only way of doing things?
If they hadn't continued with their rapid iterative testing ultimately providing competition, then we'd still be waiting on the NASA pork train to produce anything

 

[Penfold101]

Not in the traditional big concrete trench sense, that some are adamant they need.

Instead they are having a big upside down steel showerhead to spray water upwards (booster bidet )


And not challenge any of the decisions made (and largely unchanged) since the 60s, blindly accepting that as the only way of doing things?
If they hadn't continued with their rapid iterative testing ultimately providing competition, then we'd still be waiting on the NASA pork train to produce anything

NASA have a post-SLS launch pad they can use, and SpaceX covered half of Boca Chicka with lumps of concrete. I know which I’d prefer.

 

[TNA]

Not in the traditional big concrete trench sense, that some are adamant they need.

Instead they are having a big upside down steel showerhead to spray water upwards (booster bidet )

 

[Chuk_Chuk]

And not challenge any of the decisions made (and largely unchanged) since the 60s, blindly accepting that as the only way of doing things?

"We've always done it this way"
Useful in some scenarios, but mostly a hinderance.

I hate that saying, I was butting heads in my previous job because of it.

 

[Penfold101]

"We've always done it this way"
Useful in some scenarios, but mostly a hinderance.

I hate that saying, I was butting heads in my previous job because of it.

It doesn’t mean you change things for the sake of it - if it’s always been done a certain way, maybe that’s because it works.

Both viewpoints are equally valid.

 

[Chuk_Chuk]

It doesn’t mean you change things for the sake of it - if it’s always been done a certain way, maybe that’s because it works.

Aaah yes the twin sister "If it ain't broke, don't fix it". Rockets weren't broken when SpaceX started

When people say "we've always done it this way", it's usually because they don't have an actual reason or have an understanding, as to why things are done that way.

If a person actually understood why things are done a certain way they would explain why and the issues with any new proposal. Hence it is mostly used to reinforce the continuous usage of an action that they themselves do not fully understand. That is why it is a bad phrase.

Both viewpoints are equally valid.

If you read my post properly you would have seen I did acknowledge that

 

[Armageus]

It doesn’t mean you change things for the sake of it - if it’s always been done a certain way, maybe that’s because it works.

But perhaps that's not the only way of doing things. It was possibly the only viable option 60 years ago, but with both advances in construction, and advances in computer modelling and simulation, then other avenues are surely worth exploring

 

[Penfold101]

But perhaps that's not the only way of doing things. It was possibly the only viable option 60 years ago, but with both advances in construction, and advances in computer modelling and simulation, then other avenues are surely worth exploring

Absolutely - I don’t think anyone would expect a solid lump of concrete to be the way forward though…

 

[Colonel_Klinck]

when you are dealing with 17m lbs of thrust it might be sensible to go with the tried and tested. This water cooled plate will bounce back a lot of the thrust at Starship which is a big part of what a flame trench is there to avoid, the only thing that will partially block that is the water deluge system. Also the rest of the thrust that is defected sideways is still going to throw up huge amounts of dirt and dust unless they plan to concrete everything around the launch pad out to a couple of hundred meters. Flame trenches can throw that all in one direction, like into the sea.

I guess as this is just a test sight where they will never run commercial flights from they probably want to avoid the cost of building up the area to avoid the water table as NASA had to do at the Kennedy Space Centre.

 

[Chuk_Chuk]

when you are dealing with 17m lbs of thrust it might be sensible to go with the tried and tested.

If it was a final rocket design then yes. But this is is the testing phase, so testing they will do.

 

[kaiowas]

when you are dealing with 17m lbs of thrust it might be sensible to go with the tried and tested. This water cooled plate will bounce back a lot of the thrust at Starship which is a big part of what a flame trench is there to avoid, the only thing that will partially block that is the water deluge system. Also the rest of the thrust that is defected sideways is still going to throw up huge amounts of dirt and dust unless they plan to concrete everything around the launch pad out to a couple of hundred meters. Flame trenches can throw that all in one direction, like into the sea.

I guess as this is just a test sight where they will never run commercial flights from they probably want to avoid the cost of building up the area to avoid the water table as NASA had to do at the Kennedy Space Centre.

Your last paragraph is key to this. It’s a test site, in the early stages of testing a new rocket. There’s a fairly high chance of a catastrophic failure on the pad destroying the whole of stage 0 hence there’s little incentive to go installing a platinum grade solution until they have confidence that this isn’t going to happen. I’m pretty sure SpaceX always knew the concrete pad wasn’t a viable long term solution but it was expected to be good enough to get them through the early test objectives. Seeing as the first flight successfully cleared the tower (even with the issues encountered) they would be more likely to put more resources into the launch infrastructure knowing that the chance of blowing it up are reduced.

 

[PlacidCasual]

I imagine one of the desires to avoid a flame trench comes from how they are looking to operate Stage Zero. The launch mount is also a maintenance platform we see routine engine swap outs from beneath and I think they are trying to maintain this flexibility which is limiting some of their design choices. But it does underpin the rapid reusability model so is worthwhile chasing.

 

[Penfold101]

Hopefully they can come up with a design to make the launch pad rapidly reusable too…

 

[Colonel_Klinck]

I imagine one of the desires to avoid a flame trench comes from how they are looking to operate Stage Zero. The launch mount is also a maintenance platform we see routine engine swap outs from beneath and I think they are trying to maintain this flexibility which is limiting some of their design choices. But it does underpin the rapid reusability model so is worthwhile chasing.

I can't see them ever being allowed to launch the kinds of numbers from land Elon was/is talking about. No way the FAA will allow daily launches, even weekly will likely be denied due to the noise from Starship. They are going to have to come up with an offshore option and if that is some kind of old oil rig for example then the flame trench is moot, the sea is fine with all that thrust.

 

[Chuk_Chuk]

So here is a video that recaps the information Elon Shared on Twitter spaces

Some key take aways.
They intentionally did not start 3 of the engines at launch. IMO it was probably to test lift off capabilities with the minimum number of engines required for lift off.

One engine failed mid flight that caused a cascade of engine failures and a loss of thrust vectoring. Which lead to the ultimate demise of the rocket.

Stage separation did not fail. They didn’t try to separate the rocket as they did not get to the correct altitude.

Flight termination did not perform as expected. A bigger charge will be needed to ensure the tanks rupture fully and much more quickly.

It’s believed that stage 0 had failed due to soil compression. Which then lead to the concrete cracking.

Due to the time it took to start the engines, starship sat on the pad for 5 seconds with some engines burning before lifting off. They are looking to speed up the time it takes to start the engine.

 

[Colonel_Klinck]

So here is a video that recaps the information Elon Shared on Twitter spaces

Some key take aways.
They intentionally did not start 3 of the engines at launch. IMO it was probably to test lift off capabilities with the minimum number of engines required for lift off.

One engine failed mid flight that caused a cascade of engine failures and a loss of thrust vectoring. Which lead to the ultimate demise of the rocket.

Stage separation did not fail. They didn’t try to separate the rocket as they did not get to the correct altitude.

Flight termination did not perform as expected. A bigger charge will be needed to ensure the tanks rupture fully and much more quickly.

It’s believed that stage 0 had failed due to soil compression. Which then lead to the concrete cracking.

Due to the time it took to start the engines, starship sat on the pad for 5 seconds with some engines burning before lifting off. They are looking to speed up the time it takes to start the engine.

That makes no sense, if the plan was to not start 3 engines you'd spread them out over the engine layout but imo you'd save a test like that for a future test, this launch had enough risks without adding that. Far more likely they had anomalies at start-up and the computers decided not to start them up.

 

[Chuk_Chuk]

That makes no sense, if the plan was to not start 3 engines you'd spread them out over the engine layout but imo you'd save a test like that for a future test,

My line of thinking is that engine failures are random, so the right thing to do, is select them at random, followed by the worst case scenario. There is no reason to choose the best case. Also losing exactly 3 engines and having the minimum number of engines necessary for lift off seems awfully convenient.

However I did, do some more digging and found this bit of information that was not present in the video. So my assumption was incorrect.

there were three engines whose ignition was terminated because the flight software did not deem them "healthy enough" to bring to full thrust

Elon Musk provides detailed review of Starship’s first launch—and what’s next

“Weirdly, we did not see evidence of the rock tornado actually damaging engines.”…

arstechnica.com

 

[Colonel_Klinck]

My line of thinking is that engine failures are random, so the right thing to do, is select them at random, followed by the worst case scenario. There is no reason to choose the best case. Also losing exactly 3 engines and having the minimum number of engines necessary for lift off seems awfully convenient.

However I did, do some more digging and found this bit of information that was not present in the video. So my assumption was incorrect.

Elon Musk provides detailed review of Starship’s first launch—and what’s next

“Weirdly, we did not see evidence of the rock tornado actually damaging engines.”…

arstechnica.com

Worst case would be 3 of the gimbling engines.

 

[Chuk_Chuk]

I hope this works out. I want to see more of this in the country

Construction starts on UK’s first vertical launch spaceport

www.imeche.org

 

[Malevolence]

The world needs more linear aerospikes.