Live data from Hacker News

SpaceX Starship rocket explodes minutes after launch from Texas

apnews.com

191–200 of 1001 posts

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#191

If you watch the this launch video, It looks like there are projectiles coming up from the pad around 18s. I wonder if the launch pad or engines were damaged by explosion. https://twitter.com/SpaceX/status/1649043715686793218

There was another view at the pad that had sizable bits of what looked like rock or concrete flying past it, camera went off line when the vehicle had barely left the ground. See the bottom right panel https://www.youtube.com/watch?v=mhJRzQsLZGg

Interesting!

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#192

Success was defined as the rocket leaving the launchpad. Suggesting that this test “failed” is at best a mischaracterisation.

This story/thread gets my upvote because it is by far the least click-bait headline I saw in a quick scan of /new. I will disagree with you though and say that the rocket stage separation failed to work. And this occurred a few minutes after launching. What would your headline be?

If the separation did not fail it probably would have made it to orbit.

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#193
post #61

People want to see 100% success in all things. But that isn't very economical. Compare the SLS to Starship. SLS has had a 100% success rate. One launch, one success. But it costs $2B per launch (and climbing) and has taken 12 years to get here. Plus, it's stealing pieces of the Space Shuttle, which was developed in the 70s over a long period of time. Starship will launch a half a dozen "failures" before they achieve…

Interesting thought: Starship just expended more engines on a *test* (39?) than I believe the entire SLS program has budgeted through the end of the 2020's (16 from shuttle + 18 new = 34?). edit: Never mind, it's slightly less – see the comment below correcting me. The SLS program has 40, not 34, RS-25's.

Yep. And they are trying to get Raptor 2 to less than $2M a pop (iirc). The "cattle not pets" of rocket science.

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#196

Earlier quoted context omitted.

Sure, but, nevertheless, I’d like to know why it exploded before declaring this a success!

It likely exploded because they blew it up (flight termination system). It looks like the stages failed to separate and it started to spin. In this case they don’t let an uncontrollable rocket just fly off and see where it comes down, they blow it up. The FTS is basically an explosive mounted to the rocket that can be remotely detonated exactly for situations like this.

I kinda wish they'd have let it keep going in order to get the telemetry.

The altitude and velocity when things went sideways were in MRBM territory, not ICBM territory so the only thing they would have hit would have been the Atlantic ocean.

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#198
post #61

People want to see 100% success in all things. But that isn't very economical. Compare the SLS to Starship. SLS has had a 100% success rate. One launch, one success. But it costs $2B per launch (and climbing) and has taken 12 years to get here. Plus, it's stealing pieces of the Space Shuttle, which was developed in the 70s over a long period of time. Starship will launch a half a dozen "failures" before they achieve…

>> People want to see 100% success in all things. But that isn't very economical.

That sounds logical, but isn't really a thing in aerospace/space. Complicated high-energy systems have thousands of failure points. So to have any chance of success each failure point needs to be engineered below, by way of example, a 0.0001% chance of failure. That costs lots of money. But say one decides to accept more risk for less cost. Ok. So you switch from 0.0001 to 0.001 failure rates. You risk is now 10-fold higher at each failure point, but with thousands of failure points adding up you are now essentially doomed. And you haven't saved anything. The cost of 0.001 components isn't fundamentally different than the 0.0001 components were. SpaceX can save money though different business practices, by trimming people/money/contracts/compliance and such, but if you look at their rockets they are not fundamentally any less-perfect than anyone else's. They cannot afford to be. This is why rocket failures, like aircraft failures, are taken so seriously. There is an extremely fine line between "works ever time" and "never worked twice" with very little money to be saved between the two.

Across many areas, risk-v-cost math never really happens. It is either go or no go. Take CPU production. Intel spends billions at each of hundreds of fabrication step to push down miniscule error rates because any of a million errors can destroy a chip. There is no money to be saved by allowing any one process to become less than as perfect as it can possibly be. A detected slip from 0.0001 to 0.001 at any step would result in an entire fab being shut down in order to diagnose the problem. The marginal savings of a less-than-perfect process isn't worth the exponential increase in the risk of total system failure.

Re: SpaceX Starship rocket explodes minutes after launch from Texas

#199

Success was defined as the rocket leaving the launchpad. Suggesting that this test “failed” is at best a mischaracterisation.

It almost blew up on the launchpad (see the debris flying after a few seconds), then at around 30 seconds you can see some explosion at the bottom, throwing away some surface parts. Multiple failed engines. Then it went into an unsurvivable "tailspin" if there was any crew around. Cheering for failure was the topping.
Post reply on HN