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Mostly agree with your positive conclusions- but I can’t help thinking about the poor judgement re the known weaknesses of the launchpad. The concrete was nowhere near strong enough to withstand that much thrust - thousands of lumps of flying concrete are obviously going to damage the engines, they were lucky that none of them pierced the fuel tanks

Elon chimed in on Twitter:

    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.

https://twitter.com/elonmusk/status/1649523985837686784?s=20

OK Elon, they used flame trenches since Gemini. Why did you not start building one 6 months ago, then it would have been ready in time for the launch?

From what I understand, when they plan to land on the Moon or Mars, they won't have a flame trench setup (on the Moon/Mars), so it needs to be able to land and take off from the ground.

Yeah but there's a huge difference between fully loaded in earth's gravity and (a smaller stage) partially empty in less gravity.

Moon or Mars would only get the second stage of the starship, with 9 engines (was it?), not the super-heavy with dozens. So, it's okay to only have the flame trench on Earth.

How are FAA and EPA going to view the event? What are the external ramifications for SpaceX for this event?

FAA has already grounded Starship from further flights after this event, till they investigate matter on their own. There are also reports of dust clouds triggered by the explosion in Texas dropping dust in a large area in Texas.

Just FYI, they always ground vehicles after they explode, until the investigation clears them as safe (within bounds of the license).

So this is par for the course, and unless the investigation turns up an issue that entails unacceptable risk to people, natural environment, or built environment we should see a return to flight as soon as the launchpad is rebuilt etc.

Are the remnants of rocket fuel mixed into the dust hazardous?

SpaceX has specifically told folks in the town not to touch any debris or handle and call them.

They are also VERY careful about handling dragon capsules etc. though I think that’s more for the thruster, rather than the engines.

I know ch4+o2 should convert to co2 and h2o but I’m unsure what other particulate could be included in the dust. Like concrete remnants (concrete dust is really bad to breathe) paint, or other additives or chemicals that were still n the pad and rocket.

It's mostly silica dust from concrete turning into powder, you don't want to breathe it for sure, but it's not like this is a rocket filled with hypergolic fuels.

> reports of dust clouds

I wonder if Texas experiences any natural dust storms.

would have blown up the propellent farm as well which sets you back with regulatory agencies.

This is Texas. You get a tax break for causing accidental explosions, based on the kilotonnage achieved.

This is still in the USA. They still had to get approval from the EPA to set up all of this stuff. I realize this comment is satire, but the reason this location was chosen has to do with orbital mechanics. A launch pad close to the equator can send payloads to a larger range of orbital inclinations.

Your comment makes me wonder why Mexico doesn’t have a launch facility. And if I remember correctly Costa Rica actually builds rocket parts.

You're right, Mexico would be a better place to launch rockets from. You want to be close to the equator, and on an east coast so you can launch rockets over the water and avoid dropping boosters on people. Rockets generally are launched to the east to take advantage of Earth's rotation (we're all moving about 1,000 mph to the east, so launching west requires about 2,000mph extra Delta v). SpaceX is a USA company, and I believe their rocket technology is considered a government secret and must stay in the USA. So that's why SpaceX themselves aren't putting launch pads in Mexico.

Also I believe equatorial orbits are still possible to achieve from USA launch sites, it just means more fuel/ reduced payload.

Interestingly, the James Webb telescope was launched from French Guiana, which is almost right on the equator.

Also Israel is one of the few countries that regularly launches their rockets to the west, as they only have a West Coast.

If the earth is rotating to the east, and we launch a rocket that drops boosters from the east coast, doesn't that mean that the land mass would move under where the boosters would drop? Wouldn't the earth need to be rotating towards the west for it to move the land mass away from the launch site?

It you are in a room, and you jump, does the wall suddenly slam into you at 1,000 mph? Why or why not?

Because I already have momentum from the earth, but a rocket will be disconnected from the earth for far longer than I would be jumping. The path of a rocket would start to curve away from the launch site due to no longer being connected from the earth for such a long time.

1) An object will maintain its momentum forever unless some force acts upon it.

2) In the case of the rocket, it accelerates eastward. Even if parts fall off, and they slow down because of the drag of the atmosphere, and they slow down all the way to the speed of the atmosphere, the atmosphere is more or less moving eastward at the same speed as the earth's rotation, so any part would be unlikely to land any further west than where it detached from the rocket. And if there was no atmosphere on earth any part that fell off a rocket during its ascent to orbit would fall according to a ballistic trajectory and would most certainly land farther east than where it fell.

So there's no friction from the atmosphere?

"friction from the atmosphere" = drag. The previous commenter explains the effect friction has.

That's Aristotle physics.

Friction doesn't exist I guess. Spherical cow and all that?

It's more complicated than that.

For example, even though Rocket Lab was founded in New Zealand it is now a US based company. It operates launch facilities both in New Zealand and the US and pretty sure it builds stuff in both countries.

What government secrets?

Rockets fall under some pretty big restrictions government wise. You know, guided missiles and all that. While SpaceX is a private company, the people allowed to work on their rockets are very much restricted. I believe they can employ Americans and Canadians, but anyone else is not allowed to work there.

The European Space Agency launches out of French Guiana in South America for this reason.

I assume we don't launch out of Mexico because rocket technology is tightly controlled by ITAR, so there's no way the government would allow any of it to go to another country's sovereign territory.

On the other hand the United States has a lot of overseas colonies which are nearer to the equator. Puerto Rico, US Virgin Islands in the Caribbean, a lot of atolls in the pacific, Guam. Even Hawaii is more southern.

I assume shipping to the launch pads is a major issue, especially for the Apollo, Space Shuttle and SLS programs which were/are build all over the place in the continental US.

> * FTS (flight termination system) worked,

Yeah, it seems it did eventually. Yet, I'm surprised that it took a whopping minute (25% of total flight time) to ignite after deviation from the flight plan. Was that intended too?

As long as you leave runway to safely set it off, you'd want to delay it as much as safely possible to collect as much data as possible. The cost of this launch spread over 3 minutes means the cost per second is extremely high. Another 10 seconds of data is millions of dollars worth of data.

Usually there is a defined "flight envelope" and if it deviates from that, they detonate. I'm guessing they simply waited as long as possible, and once it left the designated buffer is when they finally detonated it.

I like you. That is all.