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The shuttle lost two crews. Maybe pushing its limits in unmanned testing would have prevented those incidents.

I don't think so, because both losses were due to bad management decisions under irrational political pressure, not any lack of engineering knowledge that more unmanned testing could have provided.

Challenger was lost because NASA ignored a critical flight risk with the SRB joint O-rings. And by "ignored", I mean "documented that the risk existed, that it could result in loss of vehicle and loss of lives of the crew, and then waived the risk so the Shuttle could keep flying instead of being grounded until the issue was fixed". They didn't need more unmanned testing to find the issue; they needed to stop ignoring it. But that was politically unacceptable since it would have meant grounding the Shuttle until the issue was fixed.

Columbia was lost because NASA ignored the risks of tile damage due to their belief that it couldn't be fixed anyway once the Shuttle was in orbit. But that meant NASA also devoted no effort to eliminating the risk of tile damage by fixing the issue that caused it. Which again would have been politically unacceptable since it would have meant grounding the Shuttle until the issue was fixed.


Wrong. Both were lost because of a fundamentally BAD ARCHITECTURE. And that architecture was bad because the NASA engineers who designed it, had never designed anything like it before and were never able to test or evaluate any of their assumptions.

Columbia would not have been lost if the Shuttle was top stacked, instead of side stacked.

Challenger would not have been lost if not for the use of solid rockets to launch humans.

Both of these design decisions were done to reduce development effort.


> They didn't need more unmanned testing to find the issue; they needed to stop ignoring it.

Should such testing have been needed? No.

Was such testing needed, given NASA's political pressures and management? Maybe. Unmanned testing in similar conditions before putting humans on it might've resulted in a nice explosion without loss of life that would've been much harder to ignore than "the hypothesizing of those worrywart engineers," and might've provided the necessary ammunition to resist said political pressures.


> Unmanned testing in similar conditions before putting humans on it might've resulted in a nice explosion without loss of life that would've been much harder to ignore

The loss of the Challenger was the 25th manned orbital mission. So we can expect that it might have taken 25 unmanned missions to cause a similar loss of vehicle. But what would those 25 unmanned missions have been doing? There just wasn't 25 unmanned missions' worth of things to find out. That's also far more unmanned missions than were flown on any previous NASA space program before manned flights began.

Even leaving the above aside, if it would have been politically possible to even fly that many unmanned missions, it would have been politically possible to ground the Shuttle even after manned missions started based on the obvious signs of problems with the SRB joint O-rings. There were, IIRC, at least a dozen previous manned flights which showed issues. There were also good critiques of the design available at the time--which, in the kind of political environment you're imagining, would have been listened to. That design might not even have made it into the final Shuttle when it was flown.

In short, I don't see your alternative scenario as plausible, because the very things that would have been required to make it possible would also have made it unnecessary.


Record low launch temperatures are exactly the kind of boundary pushing conditions that would warrant unmanned testing in a way that not all of those previous 25 would have been. Then again, so was the first launch, and that was manned.

> I don't see your alternative scenario as plausible

Valid.


> Record low launch temperatures

Were not necessary to show problems with the SRB joint O-rings. There had been previous problems noted on flights at temperatures up to 75 degrees F. And the Thiokol engineers had test stand data showing that the O-rings were not fully sealing the joint even at 100 degrees F. Any rational assessment of the data would have concluded that the joint was unacceptably risky at any temperature.

It might have been true that a flight at 29 degrees F (the estimated O-ring temperature at the Challenger launch) was a little more unacceptably risky than a flight at a higher temperature. But that was actually a relatively minor point. The reason the Thiokol engineers focused on the low temperature the night before the Challenger launch was not because they had a solid case, or even a reasonable suspicion, that launching at that cold a temperature was too risky as compared with launching at higher temperatures. It was because NASA had already ignored much better arguments that they had advanced previously, and they were trying to find something, anything, to get NASA to stop at least some launches, given that they knew NASA was not going to stop all launches for political reasons.

And just to round off this issue, other SRB joint designs have been well known since, I believe, the 1960s, that do not have the issue the Shuttle SRBs had, and can be launched just fine at temperatures much colder than 29 F (for example, a launch from Siberia in the winter). So it's not even the case that SRB launches at such cold temperatures were unknown or not well understood prior to the Challenger launch. The Shuttle design simply was braindead in this respect (for political reasons).


I should point out that the Buran launched and took earth, with bad conditions, completely automated. It's sad how it ended.

> So we can expect that it might have taken 25 unmanned missions to cause a similar loss of vehicle.

That doesn't follow. If those were unmanned test flights pushing the vehicle limits you can't just assume they would have gone as they actually did.


> If those were unmanned test flights pushing the vehicle limits

As far as the launch to orbit, which was the flight phase when Challenger was lost, every Shuttle flight pushed the vehicle to its limits. That was unavoidable. There was no way to do a launch that was any more stressful than the actual launches were.


You can push the environmental conditions of the launch e.g. winds and temperatures.

See my response to Mauling Monkey upthread on why the cold temperature of the Challenger launch actually wasn't the major issue it was made out to be.

Note also my comments there about other SRB designs that were known well before the Shuttle and the range of temperatures they could launch in. Those designs were used on many unmanned flights for years before the Shuttle was even designed. So in this respect, the unmanned test work had already been done. The Shuttle designers just refused to take advantage of all that knowledge for braindead political reasons.


Testing wasn't really the issue with the loss of the two shuttles. In both cases, it was mostly a management issue. For Challenger NASA had seen o-ring erosion in earlier launches, and decided it was not a big risk to the crew. Then they launched Challenger against the recommendations of the engineers in charge of o-ring seals. For Columbia, they has seen foam strikes in earlier launches, but since they had not caused catastrophe in the past, they decided that foam strikes were acceptable. Even when it was clear that a large foam strike had occurred on the launch of Columbia, management wasn't concerned enough to try to get ground-based images of the shuttle to check for damage. Could Columbia's crew have been saved had they known the extent of the damage? No one can say of course, but not even trying to do everything possible was inexcusable.

They very nearly lost the first shuttle they launched. Jumping straight into manned testing was quite reckless, but politically necessary. If they had tested the shuttle without crew, that would have gotten people thinking that crews probably aren't necessary for a lot of shuttle missions, in particular launching satellites. It also would have prompted people to compare the cost of shuttle launches to other unmanned rocket launches, in particular for commercial satellite launches (which they were doing until the Challenger disaster.) These are comparisons that would have been very problematic for NASA as a political entity.

> They very nearly lost the first shuttle they launched.

Which mission are you referring to?

If it's STS-1, AFAIK there were no close call incidents during the actual flight, but the mission commander, John Young, did have to veto a suggestion to make that mission an RTLS abort instead of an actual orbital flight. Doing that would have been reckless, yes: Young's reason for not doing it was "Let's not practice Russian roulette."


The overpressure caused by the SRB ignitions exceeded predictions due to the geometry of the launch pad. This overpressure forced the orbiter's bodyflap away, beyond the design limits of the hydraulic system that controls it. John Young said that if he had known this, he would have ejected, which would have caused the loss of the shuttle.

Ah, I see. But in fact the body flap was not inoperative, and the Shuttle landed safely. So this looks to me like a case where Mission Control turned out to be justified in not telling the crew what had happened.

One thing I wonder about is whether it would have been possible to test the flap while in orbit, to see if the hydraulic lines were actually ruptured or not.


They made the right call, kind of, and only by accident. John Young had telemetry for the flap available to him in the cockpit but didn't notice it happen at the time. NASA ground control also had the telemetry, but also didn't notice / understand until after it was too late to eject (which was only possible during a narrow window for ascent, and not at all for reentry if the body flap had been inoperable.) They also simply got lucky the hydraulic system performed beyond it's designed safety margin.

The lesson is that people can be irrational even it the logic is sound.

The problem there is the Shuttle was deliberately designed so it couldn’t be flown unmanned, which risked lives and wasted money for lots of simple satellite launches.

If the value is in deception.

The old, they had it coming defence of genocide.

If you play with fire you might get burned.

Hamas and friends understand this and rely on western morality to protect them from complete annihilation. They may have miscalculated how often you could kick the dog before it bit back.

This, of course, cuts both ways.


> Also, the S and X models are old and their market segment is heavily saturated at this point so it makes sense for Tesla to exit those model lines.

Car companies typically invest in new models in the same segment in order to stay competitive with the other car companies.


Tesla is not your average car company.

> I haven't come across a cab that is suspension isolated from the frame of a conventional, even though the axles are on air.

They are very often on a simple suspension. The cab will have a pivoting mount at the front and sit on air springs in the back.


I'm wondering how much the output quality of a small model could be boosted by taking multiple goes at it. Generate 20 answers and feed them back through with a "rank these responses" prompt. Or doing something like MCTS.

Isn't this what thinking models do internally? Chain of thoughts?

No. Chain of thought it just the model generating a single answer for longer inside <think></think> tags which are not shown in the final response. The strategy of generating different answers in parallel is something different (which can be used in conjunction with chain of thought) and is the thing used by models like Gemini 3 Deep Think and GPT-5.2 Pro.

Hmm.. got it. Thanks..

Was the Hindenburg disaster really what killed airships, or was it the airplane?

> legal liability is on the person who posts it, not who hosts the tool.

In the specific case of grok posting deepfake nudes on X. Doesn't X both create and post the deepfake?

My understanding was, Bob replies in Alice's thread, "@grok make a nude photo of Alice" then grok replies in the thread with the fake photo.


That specific action is still instigated by Bob.

Where grok is at risk is not responding after they are notified of the issue. It’s trivial for grock to ban some keywords here and they aren’t, that’s a legal issue.


Sure Bob is instigating the harassment, then X.com is actually doing the harassment. Or at least, that's the case plaintiff's attorneys are surely going to be arguing.

I don't see how it's fundamentally any different to mailing someone harassing messages or distressing objects.

Sure, in this context the person who mails the item is the one instigating the harassment but it's the postal network that's facilitating it and actually performing the "last mile" of harassment.


The very first time it happened X is likely off the hook.

However notification plays a role here, there’s a bunch of things the post office does if someone tries to use them to do this regularly and you ask the post office to do something. The issue therefore is if people complain and then X does absolutely nothing while having a plethora of reasonable options to stop this harassment.

https://faq.usps.com/s/article/What-Options-Do-I-Have-Regard...

You may file PS Form 1500 at a local Post Office to prevent receipt of unwanted obscene materials in the mail or to stop receipt of "obscene" materials in the mail. The Post Office offers two programs to help you protect yourself (and your eligible minor children).


Grok posts the pictures publicly, everyone can see them.

The postal network transports a letter, and only the person reading the letter can see the contents.

These situations are in no way comparable.


The difference is the post office isn't writing the letter.

if grok never existed and X instead ran a black-box-implementation "press button receive CP" webapp, X would be legally culpable and liable each time a user pressed the button, for production plus distribution

the same is true if the webapp has a blank "type what you want I'll make it for you" field and the user types "CP" and the webapp makes it.


That's NVME storage in your test?

Yes, a WD_BLACK 4TB SN850X NVMe.

> The sci fi version of the alignment problem is about AI agents having their own motives

The sci-fi version is alignment (not intrinsic motivation) though. Hal 9000 doesn't turn on the crew because it has intrinsic motivation, it turns on the crew because of how the secret instruction the AI expert didn't know about interacts with the others.


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