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Comment Re:Self-accelerating decomposition (Score 1) 96

Making turbine blades, whether for plane engines or fixed power, is one of those fantastically expensive and complicated processes that we don't really build excess capability for it.
So any serious increase in demand first requires building more manufacturing capacity, whether that be in the USA, China, or elsewhere.
And the manufacturing equipment alone demands like a year's lead.

Comment Re:Jet engines (Score 1) 96

Combined cycle gas turbines can be 60-62% efficient. This is burning the gas in a turbine then scavenging the heat in a steam boiler.
Simple cycle turbines are 30-40%
Boilers are 33-42%, supercritical 45-47%
The biggest diesels in the world barely bust 50%.
Turbines, like with ICE engines, can be designed to produce more power for their size or be more efficient. Generally speaking, efficiency is emphasized for fixed installs. Bigger for a given power is more efficient.

Comment Jet engine efficiency (Score 1) 96

It depends on how it is set up. A combined cycle gas turbine system can hit 62% by burning the gas in a turbine then using the waste heat to run a boiler with its own turbine.
Around 30-40% just for the simple cycle, without heat scavenging.
Boiler systems are 33-42%, close enough that the exact install matters compared to a simple cycle turbine.
Get very fancy and very hot with the boiler and you might hit 47%.

Comment Re:My last corvette (Score 0) 218

I have a 2020 Toyota, it had the whole proprietary ecosystem. I tried it a bit, never got it to work even half-way decently, and they ended up shutting it down in 2024, to my understanding leaving a lot of people hanging with even newer vehicles than mine.
Integration was bad enough that just putting a cell phone holder to use google maps on it was better.
It was the last year before Toyota folded and put in android auto and apple carplay.
I would have never bought the car - but, well, a different family member got caught DUI, so I got the car.

Comment Re:Already has (Score 1) 103

I think we need to shoot more for "average". My mom regularly tosses her phone at me telling me to fix it.
I have to explain the remote regularly.
Sure, there are technies that actually built those boxes, but just as many people who just want to watch video.

Comment Re:These cars should have to pass drivers ed tests (Score 2) 45

People who have taken driver's ed still make damn foolish mistakes. As is Waymo currently has a lower accident rate per mile driven than humans do on average.

As such, I consider 'we were made aware of the problem and deployed a fix' to be an acceptable outcome. Much like a teenager who just upgraded from a learner's permit, they should keep improving.

As they keep identifying and fixing bugs, IE incorrect driving decisions, the rate should keep dropping until they're better than all but the best human drivers.

Comment Re:So what, all 12 people? (Score 1) 131

They have about the same population density, around the same amount of roads by population, etc...
We can care because they make for a good test case, especially for the northern USA.

It's like how polling around 1k people should give pretty good results for any question for the entire country, within 3%. Around 10k people for a 95% chance of being within 1% (where exact methodology to ensure a true random sample may be more important).

Now, we shouldn't assume any experience will be 100% the same, but on average we should see similar results.

Comment Re:numbers (Score 1) 131

So Norway has a car for every 1.9 people, and the USA for every 1.2 people.
While a significant difference, it isn't like it is an order of magnitude difference. I also remember seeing figures that places Norway at around the same population density as the USA, and about the same number of roads and distance driven per year.
I'd argue that Norway can and should be examined to inform on actions inside the USA, especially northern areas.

Comment Re:Refuel in orbit [Re: I'm rooting for it!!] (Score 1) 166

I want to remind you that I never said 400 tons of fuel, I just used your numbers. I said 8 launches, calling Musk's 4 bull. Even with only 100 tons/fuel per launch, that's 800 tons without changing stuff up should be allow them to stuff more fuel into starship, saving weight via not needing other cargo stuff, just bigger tanks.

Also, I said "reach the moon", not "land on it".

And changing development timelines is pretty normal.

Comment Re:Refuel in orbit [Re: I'm rooting for it!!] (Score 1) 166

You're still rewriting the proposals to get your figures.
It isn't 100 tons of fuel per launch, it is closer to 150 that they are figuring. Hundreds of m/s is still many tons of fuel.
10 launches, not 16.
400 tons of fuel plus 220 tons is 620T total, that is about 65% fuel, easily enough to reach the moon.
Landing with 220T would need some more, but as I said, i discounted Musk's statement.

Besides, who says we'll go to the moon with v3 instead of the 200t v4?

And with saying a year or more for 5 launches, SpaceX is expending starships faster now. There isn’t any real reason to thing that they won't have 4 or more rockets and be able to turn them around quickly to get the fuel launched rapidly. Lots of testing and development first though. I'll fully admit that.
Basically just figure that starship will have to same reuse abilities as falcon 9, roughly.

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