SpaceX go boom!

[Elp]

No flame pit? Who's running the programme?!?

[Astronomist]

Some mad billionaire I suppose. . .

[DaveS]

24 minutes ago, Stu said:

Well they can certainly examine this in person! Huge amount of damage to the launch pad (table?) that will need to be rebuilt with a flame pit/channel I bet. Not sure why made them think they didn’t need one.

Well, I guess that's one way to dig a flame trench 🤣

[Macavity]

I think it is quite easy to dish the DIRT on public figures... If you live in a place
called Port Isabel maybe? lol. In fairness, this is the first time, where we have
someone "doing stuff" and (effectively) impacting how stuff is reported? 😛

Dunno about you, but I discover (via Facebook) some of my own relatives
are "campaigning" for stuff that impacts negatively (sic) on Me? lol.
(I do have to reach for the "Sleep for 30 days" button!) 😅

Edited April 21, 2023 by Macavity

[Paul M]

1 hour ago, Stu said:

Not sure why made them think they didn’t need one.

Just maybe they didn't expect it to clear the tower, thus a fancy launch pad would have been a waste of money! 🤪

It's already started excavating a pit, so it's not all bad.

[maw lod qan]

1 hour ago, Elp said:

No flame pit? Who's running the programme?!?

Have to build up to have a pit.

Water table is probably 1' below the surface.

We just love building things over here on the coast. 

Space ports, large cities. We don't mind even being a little below sea level. Makes it easier to launch your boat. 

[Elp]

So aiming for the stars is the goal spending millions to get to this point. But aiming for a few metres above ground is not deemed necessary considering the world first forces required to launch such a thing off the ground? The plans some decision making people make boggles the mind, unfortunately such decisions permeate our whole lives everyday.

Edited April 21, 2023 by Elp

[Macavity]

"Worrying" about Elon Musk (His Fans notably - Twitter possibly?), is NOT good for me! 😅
I find it easy to lose a whole DAY thinking / talking about something... so totally remote...
The old "Deathbed Regrets" thing? "I wish I'd spent more time on Twitter"? Hmmm. lol. 😛

Edited April 22, 2023 by Macavity

[saac]

This comes to mind, by Roosevelt, 

Jim

“It is not the critic who counts; not the man who points out how the strong man stumbles, or where the doer of deeds could have done them better. The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood; who strives valiantly; who errs, who comes short again and again, because there is no effort without error and shortcoming; but who does actually strive to do the deeds; who knows great enthusiasms, the great devotions; who spends himself in a worthy cause; who at the best knows in the end the triumph of high achievement, and who at the worst, if he fails, at least fails while daring greatly, so that his place shall never be with those cold and timid souls who neither know victory nor defeat.”

[Macavity]

The Scott Manley "report" is, as ever, sober, intelligent... and interesting? 😉
Perhaps it never really made it to the point where "staging" was possible?

 

[Gfamily]

On 20/04/2023 at 20:23, 900SL said:

I am struggling to see how having 33 separate engines (with all the associated plumbing, hydraulics and wiring) is a beneficial design. To this simple Engineer, it seems like multiple potential points of failure

 

What happened to KISS??

Increasing the size of each rocket engine adds more engineering complexity than increasing the number of engines.

An interesting overview of rocket engine design from Everyday Astronaut blog from 2019.

https://everydayastronaut.com/raptor-engine/

Edited April 23, 2023 by Gfamily

[malc-c]

To be honest it was doomed from the start.  After previous static fires, including the 30 raptors at reduced throttle the concrete of the pad was obliterated, and often we noticed one or two engines having to be replaced.   It doesn't take a genius to predict that some or possibly most of the engines would be damaged by the debris of the pad being thrown at them.  IMO they were lucky that only a few failed at the start and there was enough thrust to clear the tower.  I doubt that there would be anything left of the tank farm, and the crater that was formed under the pad would have been a hell of a lot bigger if startship had fallen back onto the mount seconds after lifting. 

I'm sure if a traditional flame trench and water suppression system had been installed we would have seen a more successful mission.  

[DaveS]

They can't excavate a flame trench, the water table is too high. The only option is to build up.

If they don't want to completely rebuild the OLM then they will need to install a flame diverter as well as the water deluge system.

I've been hearing multiple conflicting reports / predictions about what they have planned, including a water cooled metal plate to protect the concrete, which doesn't sound like it will work.

[ONIKKINEN]

If a concrete launch pad built here on Earth gets atomized by the engines i am left wondering how is the upper stage ever going to land and lift off from the Moon or Mars? Yeah ok fewer engines on the upper stage and not nearly as much thrust required to lift off compared to Earth, but still it all seems way too risky. The engines would excavate a massive crater on the way down and on the way up so twice the risk of some regolith rich exhaust.

[DaveS]

From what I've seen the HLS will use secondary thrusters mounted high up in the ship, so less chance of digging a crater.

But this is SpaceX, so everything could change.

[Ags]

1 hour ago, DaveS said:

They can't excavate a flame trench, the water table is too high. The only option is to build up.

If they don't want to completely rebuild the OLM then they will need to install a flame diverter as well as the water deluge system.

I've been hearing multiple conflicting reports / predictions about what they have planned, including a water cooled metal plate to protect the concrete, which doesn't sound like it will work.

Our water table in Holland is pretty high and we dig down. A bit of water can be solved with some shuttering and a big pump.

 

Edited April 24, 2023 by Ags

[SamAndrew]

1 hour ago, ONIKKINEN said:

If a concrete launch pad built here on Earth gets atomized by the engines i am left wondering how is the upper stage ever going to land and lift off from the Moon or Mars? Yeah ok fewer engines on the upper stage and not nearly as much thrust required to lift off compared to Earth, but still it all seems way too risky. The engines would excavate a massive crater on the way down and on the way up so twice the risk of some regolith rich exhaust.

The upper stage has already successfully landed on a concrete pad on Earth. You can assume the first ships to land on Mars aren't coming back (no way to refuel) so they'll be able to build a pad / launch tower for the subsequent ships that need to be able to get back to Earth. That's all a long long way down the line!

Apollo showed you can land and launch from the moon without a pad, Nasa wouldn't have picked Space X if they didn't think it was possible with Starship. 

[SamAndrew]

2 hours ago, DaveS said:

They can't excavate a flame trench, the water table is too high. The only option is to build up.

If they don't want to completely rebuild the OLM then they will need to install a flame diverter as well as the water deluge system.

I've been hearing multiple conflicting reports / predictions about what they have planned, including a water cooled metal plate to protect the concrete, which doesn't sound like it will work.

Musk has said they have a metal plate, it just wasn't ready and they assumed the concrete would last at least one launch. The metal plate just needs to stop the concrete from shattering. Part of the problem could have been that some of the engines never started, which meant it crawled off the pad massively exasperating the problem.

I think adding a few more sections to the tower and raising the pad isn't beyond the realms of possibility.

[Macavity]

I sense it's quite complex! If you turn on the kitchen tap, to deliver the finest possible stream...
Then put your finger in it... slowly approach the tap, you'll see the water jet start to "clump"! 😉
It sets up a sort of (sonic?) standing wave? The reflections are as dangerous as flying concrete.

I did read elsewhere, that the: "SOUND would kill you" at close range. 😱
Related to Rocket/Jet "Crackle" (maybe) https://youtu.be/BdCizNwLaHA

Edited April 25, 2023 by Macavity

[malc-c]

11 hours ago, SamAndrew said:

 

Apollo showed you can land and launch from the moon without a pad, Nasa wouldn't have picked Space X if they didn't think it was possible with Starship. 

But the upper section of the LEM used the lower section as a launch pad, and even then debris was scattered around the site.   

I've not seen any rendering of a starship with high level raptors installed, and AFAIK the idea was to land Starship on those short stubby legs and then use the same accent / decent motors to launch from the moon.  These would throw up dust etc so the landing pads would need to be at a safe distance to avoid any debris damaging living quarters of the intended base.

One thing that would be interesting to see is if moondust and rock could be used as an aggregate building medium, and if mixed with cement might form a resilient concrete.

Whilst I admire the drive behind SpaceX to keep the momentum going I do think that they (Musk?) are chancers and rush things.  They said that following the static fire the data suggested that the pad would be Ok, overlooking the fact that the static fire was at less thrust and for a short duration which still resulted in remedial work to the pad and better protection to the infrastructure of the pad.  If it was to impractical to dig down to install a deflector and deluge system, then raise the launch pad and surrounding area similar to pad 39a in Florida.

I'm betting that whilst Musk has said they will be good to go again in 2-3 months, even if they could rebuild the pad by then I don't think the FAA will grant a licence given the impact the first launch has made on the beech and ocean.  There will be more environmental constraints given the amount of debris that is scattered in that area.  All those groups that predicted the impact it would have are now pointing the finger at the governing bodies that granted the launch licence and saying "told you so".

 

[Astroscot2]

Im not sure the raptors can be throttled down sufficiently for landi on the Moon / Mars.  I do recall seeing a render showing the Drago thrusters being used to land "gently " on the moon.

Edited April 25, 2023 by Astroscot2

[maw lod qan]

I've been following a group from Boca Chica about the launch.

Seeing the images many took from boats and local beach, I can't help but wonder with all that fuel, what would have been the range for a RUD on the pad?

There were some viewers who went to the Mexican side of the river that if I read correctly were only 2.8 miles away.

Good for taking images, bad for shock wave and debris!