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Comment by colechristensen | Hacker News Reader

This is a minor mechanical issue scrub that nearly everyone will use to express opinions they already had about the program. Please just stop.

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> minor mechanical issue scrub

Engine fuckup is minor. But it’s also uncommon with modern engines. (At this stage, assembled and fuelled on the pad.) SLS’s choice to use an old engine is relevant to the discussion.

Very few launch vehicles get off in their first launch window. There's a lot of procedures and adjustments to get juuuust right to make a launch window 90%+ of the time.

The issue here isn't really an "engine issue", but an issue with putting cold gases through the engine so it's not thermally shocked at ignition-- some combination of lines and valves probably want a different procedure and thermal profile.

> Very few launch vehicles get off in their first launch window.

This was their 3rd launch window right?

Yep how many of space x's early attempts went up in flames?

Do you have a source for it being uncommon?

See https://www.youtube.com/watch?v=z-89xl-v0gs&t=2590s for a recent rather larger engine fuckup with the other major launch system under develop.

That’s an engine test. Not a rocket with payload attached.

You're moving the goalposts.

Still, https://www.noozhawk.com/article/missile_test_ends_in_explos... is a rocket that blew up early last month, 11 seconds into flight. See https://www.space.com/biggest-launch-failures-2021 for a list of notable failures last year.

Failures, particularly with new rockets, are much more common than you believe.

> You're moving the goalposts

Don’t believe I am. I specifically caveated “at this stage, assembled and fuelled on the pad” because an engine under a fully-assembled rocket has assumptions made about it that one on the test stand obviously does not.

> list of notable failures last year

How many of these are engine failures? None, based on my scan.

The engine can be tested separately. That makes them wildly more predictable in a way the rest of the rocket, which can’t usually be similarly tested, is not. As someone with a background in aerospace engineering, I perk up when someone’s engine fails at the pad, because that—nowadays—shouldn’t happen.

I can't avoid notice the irony that, although NASA is still investigating, you already seem to scope the issue, and troubleshoot it as a minor mechanical problem...

What's is your analysis on the SRB's being 1 month past their validity date per @gsibble reference?

Snark doesn't add much to conversations here.

It is possible for something to be preliminarily marked as minor while also still being investigated. There's no need to be pointlessly antagonistic.

> There's no need to be pointlessly antagonistic.

Did you notice the post I replied to, was asking the whole discussion to stop?

They scrubbed because the bleed procedure that cools the fuel wasn’t working. This usually doesn’t point to major issues.

alternatively you could see it as "yet another issue in a program that's been plagued with issues for years". When you find the 300th bug in the same piece of code, it's a pattern, not a coincidence.

It's also something that could have been discovered and worked way back at the wet dress rehearsal, if they'd completed it. Instead, they got a hydrogen leak that stopped the test before it got to the step that failed today. For whatever reason (GO fever?) NASA managers decided that a partial test that ended in failure was "good enough".

I agree.

Delaying the launch is not a big deal.

Launching and going boom is a big deal.

There isn't much to discuss because this is literally business as usual in this line of work.

If the opinions being expressed were "SLS is great, that launch was fantastic", would you still be trying to silence the expression of those opinions? I seriously doubt it.

I guess we'll find out if you leave such a comment in 4 days after SLS successfully launches right? Well, maybe not..

“Your opinions are no longer valid and will not be acknowledged. Please stop talking.”

Seriously. It seems like the two things that really rile up all the garbage opinions here are NASA launches and COVID posts. Holy cow, just some pure trash comments.

And cryptocurrencies, and everything by Elon Musk, and Kubernetes, and AI, and search engines, and privacy, and China, and...

Trash comments everywhere (but also good ones).

I've definitely correlated those topics to lower quality comments

How exactly can you use this news to express the opinion similar to:

“NASA & Boeing are the best, props for using cutting edge technology, SpaceX is a scam and not worth taxpayers money, Elon Musk suck!”

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