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Of course doubts are allowed, but what I'm saying is that SpaceX clearly have a team of world-class experts. They've all spend decades training, practising and

by grecy 4y ago

Of course doubts are allowed, but what I'm saying is that SpaceX clearly have a team of world-class experts. They've all spend decades training, practising and honing their craft. Based on their track record, I'd say they're pretty good at what they do. They may even be the best in the world. That makes it hard when some rando on the internet comes in to doubt or criticize, because it's virtually impossible for that rando to have more expertise than the entire SpaceX team. If a person actually run the numbers and backed up their thoughts with legitimate reasons and a better idea that would be one thing. But that never happens, which is the problem. If a government is aiming to increase the amount of renewable power, or a car company aims to make their cars more efficient, or a public transit operator wants to increase their service, or literally any one of billions of things that can be done, it is a waste of everyone's time for someone to chime in and say "Won't work because I said so" when they have absolutely zero experience, expertise or evidence to back up their thought that has no basis in reality.

brookst 4y ago
> But that never happens, which is the problem. Does it never happen, or do you just never see it? Earlier today there was an HN post of an article suggesting that the Starship launch has more environmental and property risk than FAA or SpaceX has acknowledged, using data like the fact that a 50% thrust test in February produced sound pressures of 110db three miles away, while SpaceX estimates 100% thrust will produce 90-100db at that distance. The post was flagged and removed very quickly. I don't know the provenance of the article or its author, and maybe they made numbers up out of whole cloth, but none of the HN commenters rebutted the data or conclusions, it was just lots of "this anti-progress scumbag wants us to live in communist China" ad hominems. So maybe there just is no legitimate, fact-based criticism. Or, maybe, there is and it is just filtered out from the communities I typically frequent. Seeing that this morning definitely gave me some pause.
- sgtnoodle 4y ago
  Perhaps the acoustics are different when the engines are actually accelerating a rocket, rather than held down on a test stand? Presumably, a test stand needs to direct all the sustained power outward horizontally in order to keep from being destroyed. A launch stand only needs to withstand exposure to high power for a few seconds, a relatively modest amount of total energy. Once the rocket is released and in the air, ideally all of the power is turning into kinetic energy rather than acoustic or thermal.
  - brookst 4y ago
    Yes! Those are all reasonable and plausible. It would have been great to have a discussion rather than banning the content because it dared to question SpaceX. At the very least, it was only because I happened to see the post before it was removed that I even knew that the February test produced between 10x and 100x as much sound as estimates suggested. As it stands, I don't know if your explanations are spot-on and the actual sound pressure will be as SpaceX estimates, and most people don't even know if there's a question about it. That doesn't seem... ideal, for the principles HN purports to support.
    - sgtnoodle 4y ago
      I don't know about what happened with the HN thread. I worked at SpaceX for 3 years 10 years ago, though, and at least at the time I didn't observe any hint of intentional impropriety. I personally was in a handful of meetings with NASA folk, and not only was I brutally honest with them, but I can also say that there was no one pressuring me to do otherwise. On the contrary, not that I can provide details, but I witnessed one person immediately getting fired for being less than radically honest in their external communication. I maintain a very high ethical standard for the people I choose to associate with personally and professionally. I would happily go back to working at SpaceX if there was good alignment with my personal goals. It seems unlikely since I now have kids and appreciate infinitely flexible work life balance, but I do look back fondly on my years at SpaceX. Financially and career wise, it was a mutually beneficial arrangement. I don't feel taken advantage of at all. Viewed as an investment, I can only describe my experience as a cornucopia of riches.
- grecy 4y ago
  I agree that posts getting flagged and taken off HN is a very big problem, and I think it needs to stop. This forum attracts some of the smartest and most influential people on the planet (The person most directly responsible for the search results of the biggest search engine on the planet used to contribute regularly...) Taking 'controversial' discussions off the table is a dangerous thing, because it means many real issues are never being discussed or addressed, and there is no hope of them ever being fixed. It's exactly like a family forbidding conversations about topics that are difficult. That leads to very bad things down the road, and I think HN is the same, but potentially has even more responsibility.
kitsunesoba 4y ago
I think it's fine to express relatively uninformed/layman/"gut feeling" opinions, but I also believe these posts need to be presented as such so it doesn't give readers the impression that the writer is imbuing them with undue confidence/credibility. I've learned a good deal through such posts, but that's only possible if the writer isn't presenting opinion as fact and is open to new information.

by grecy 4y ago

brookst 4y ago

> But that never happens, which is the problem. Does it never happen, or do you just never see it? Earlier today there was an HN post of an article suggesting that the Starship launch has more environmental and property risk than FAA or SpaceX has acknowledged, using data like the fact that a 50% thrust test in February produced sound pressures of 110db three miles away, while SpaceX estimates 100% thrust will produce 90-100db at that distance. The post was flagged and removed very quickly. I don't know the provenance of the article or its author, and maybe they made numbers up out of whole cloth, but none of the HN commenters rebutted the data or conclusions, it was just lots of "this anti-progress scumbag wants us to live in communist China" ad hominems. So maybe there just is no legitimate, fact-based criticism. Or, maybe, there is and it is just filtered out from the communities I typically frequent. Seeing that this morning definitely gave me some pause.

sgtnoodle 4y ago
Perhaps the acoustics are different when the engines are actually accelerating a rocket, rather than held down on a test stand? Presumably, a test stand needs to direct all the sustained power outward horizontally in order to keep from being destroyed. A launch stand only needs to withstand exposure to high power for a few seconds, a relatively modest amount of total energy. Once the rocket is released and in the air, ideally all of the power is turning into kinetic energy rather than acoustic or thermal.
- brookst 4y ago
  Yes! Those are all reasonable and plausible. It would have been great to have a discussion rather than banning the content because it dared to question SpaceX. At the very least, it was only because I happened to see the post before it was removed that I even knew that the February test produced between 10x and 100x as much sound as estimates suggested. As it stands, I don't know if your explanations are spot-on and the actual sound pressure will be as SpaceX estimates, and most people don't even know if there's a question about it. That doesn't seem... ideal, for the principles HN purports to support.
  - sgtnoodle 4y ago
    I don't know about what happened with the HN thread. I worked at SpaceX for 3 years 10 years ago, though, and at least at the time I didn't observe any hint of intentional impropriety. I personally was in a handful of meetings with NASA folk, and not only was I brutally honest with them, but I can also say that there was no one pressuring me to do otherwise. On the contrary, not that I can provide details, but I witnessed one person immediately getting fired for being less than radically honest in their external communication. I maintain a very high ethical standard for the people I choose to associate with personally and professionally. I would happily go back to working at SpaceX if there was good alignment with my personal goals. It seems unlikely since I now have kids and appreciate infinitely flexible work life balance, but I do look back fondly on my years at SpaceX. Financially and career wise, it was a mutually beneficial arrangement. I don't feel taken advantage of at all. Viewed as an investment, I can only describe my experience as a cornucopia of riches.
grecy 4y ago
I agree that posts getting flagged and taken off HN is a very big problem, and I think it needs to stop. This forum attracts some of the smartest and most influential people on the planet (The person most directly responsible for the search results of the biggest search engine on the planet used to contribute regularly...) Taking 'controversial' discussions off the table is a dangerous thing, because it means many real issues are never being discussed or addressed, and there is no hope of them ever being fixed. It's exactly like a family forbidding conversations about topics that are difficult. That leads to very bad things down the road, and I think HN is the same, but potentially has even more responsibility.

kitsunesoba 4y ago

I think it's fine to express relatively uninformed/layman/"gut feeling" opinions, but I also believe these posts need to be presented as such so it doesn't give readers the impression that the writer is imbuing them with undue confidence/credibility. I've learned a good deal through such posts, but that's only possible if the writer isn't presenting opinion as fact and is open to new information.