xenadu02

An amazing page, thanks for posting it!

I got a lathe a few years ago as a hobby and really enjoy making something with high precision by hand with no computer or LLMs involved. Of course I make everything nice because I make it twice (due to my own errors).

The history of lathes always interested me - especially how some features are so standard we think of them as integral to all lathes but that was not the case! Most lathes in use today are technically screw-cutting engine lathes.

Every increase in precision in your tools leads to even greater precision in what you can make if you are careful and clever. In that sense every machinist has to start with a lathe because a lathe is the most versatile machine and is capable of making replacement parts to improve itself. Even a relatively crude home-made lathe can be enough to machine better parts to install onto the lathe to keep improving it. Even my little import hobby lathe (PM-1030V) can make parts to a tenths precision (tenths = 10,000th of an inch or .00254mm) with some care and it is not what you would call a rigid and accurate machine.

You might wonder how humans turning a wheel were able to cut metal but in those days they didn't have HSS let alone carbide tools so they had to use whatever would hold an edge (carbon steel for a long time). That meant much much slower turning speeds, much smaller depth of cut, and much more frequent sharpening. I believe it was around 1869 Robert Mushet invented Mushet steel and later Maunsel White and Taylor worked with Bethlehem Steel Co to invent the first modern "tool steel" alloy. They are of course called High Speed Steel because they allow you to turn the work at high speed when cutting. Something of an ironic name in the modern world as carbides are far higher speed than HSS.

Manual machining has declined thanks to CNC but there are still plenty of jobs where manual machining is faster and cheaper than setting up a CNC program. Of course those of us doing it as hobby aren't bothered by such things.

It was worse than that. No one really understood or had a handle on the production process. During this time period the notion of iron being a chemical element was a recent discovery.

So what you got may have been called cast iron but what it actually was might be pig iron, gray cast iron, ductile iron, and even a bit of steel and possibly carbides mixed in. Properties varied - sometimes by a lot.

If you know even a bit about metals then when you hear "cast iron piston ring" you imagine that ring to have certain properties that match a specific type of cast iron. But in those days every single ring might vary significantly entirely due to the ore load the foundry happened to get, how they melted/cast it, how it was cooled, etc.

AI is a useful tool but it absolutely needs a lot of human guidance.

Unlike a compiler it won't give up at the first sign of trouble but that just means it left alone it will dig bigger and bigger holes.

Treat prompt engineering as a discipline and refine your technique. When it produces garbage throw out the work and start over until you figure it out.

The format is SSIM defined by IATA - the international association of transport airlines. It specifies two letter airline code followed by four digit flight.

I'm sure various ATC systems also assume this.

Changing it would be an industry-wide effort.

That's the death trap of silicon boom-bust cycles that have claimed so many in the industry. Demand surges, you start expanding, the bust arrives, you go out of business.

Micron is putting up over $100 billion for this expansion wave IIRC. You can't afford that unless you are certain the increase in demand is sustainable.

You want to assure investors that investment will pay off so you want to talk up your order book and market outlook.

You also want to take as much profit as you can now so if things turn against you it doesn't mean bankruptcy. A pile of cash fixes many problems :)

Micron has several fabs and fab upgrades coming online or under construction right now. An expansion in Boise and Virginia. Plus a huge megafab project in New York that's going to be the biggest in the world AFAIK.

All the DRAM makers have new fabs or plant expansions underway right now - indicating they believe the demand increase to be sustainable.

It works right up until some form of revolution, either politically or violently. We are far from anything like that but I'd rather not get close to the line. I think I'm a minority view though, despite being in the top 10% myself.

It is also shocking how little my life compares to the rich people I see. I don't own two houses or a yacht. We don't take yearly vacations to a chateau in France. The gap between the top 10% and the top 1% is insane. The gap between the 1% and the 0.1% is even larger still.

But hey... not like the rich getting richer and saying "screw you" to everyone else has ever led to negative consequences right? Nothing to see here, business as usual.

No I was just saying Fujitsu never really made a play for any US marketshare. They had ways to go about it but they stuck to what they knew: high-touch sales, locked down support, focus on the Fortune 1000.

That's too bad.

I'm saying Fujitsu never made any real attempt to sell their product to anyone except very large companies with purchasing departments. Thus it is little wonder they never really got much in the way of sales.

Maybe that strategy works in Japan or Asia but it didn't work here and I think that's a shame because we could have used the competition.

Yes that's true. They knew before but at 1500 they should have gone around. At "minimums" callout they should have gone around. When they floated so far down the runway they should have gone around.

Instead they waited until they were about to go off the end with idle engines to try it - the one time it was too late to go around.

> The same way Congress has been subsidizing Boeing and its competitors

Funny you should mention that. Boeing deliberately buys 35% of a 787's airframe from Japan (along with other equipment for the 787 and other models).

That's a deliberate play: we buy a lot of parts from Japanese companies, your airlines buy mostly Boeing airplanes. Even today despite some diversification Boeing has over 70% marketshare in Japan.

If you ever wondered why Airbus setup factories in the USA that's a similar deal. The US Gov and Mil want to ensure factories and workforce on home soil should the need arise. In some unrecorded meetings somewhere strong hints were no doubt dropped that it would be in Airbus' best interest to play ball. They obliged.

That said the USA is the largest supplier of parts for Airbus airliners so there's also a benefit to having aerospace manufacturing and R&D here.

Ubiquity proved you can bust into the market from the bottom end if you want. Nothing was stopping them from doing the same but like many companies they prefer to focus on how much money they can siphon from the Fortune 1000 so I can't say I feel sorry for them.

If we exclude short-term shortages then no. The cost to make a wafer hasn't really changed. Larger wafers improved costs but that's about it AFAIK.

Feature sizes have been shrinking unevenly for two decades now combined with the overall slowdown in improvements. Transistors themselves are FinFET geometry and something like 15-30 atoms thick and maybe 80-100 across. There ain't much juice left to squeeze in terms of size but perhaps we'll figure out how to reduce leakage (heat).

Physics hates the very large and the very small. The large get the tyranny of volume scaling + general relativity. The small have their entire concept of reality smashed by quantum mechanics.

We don't.

Prior to LLMs there was some minimal effort required to snipe someone and possibly your reputation was attached otherwise there would have been no point in publishing to begin with.

Now anyone with a few dollars can do it, many who don't have a reputation to worry about.

It's the same problem as YouTube AI slop, AI-generated music, and everything else. Don't you dare tweet or blog about a video idea or hum a few bars from a song - within an hour 27 people will have posted AI slop rip-offs. There's something uniquely depressing about being beaten to the punch by a thief that doesn't deliver the same soul-crushing impact as having someone copy you after the fact.

Part of the problem is they got into this mess because they were behind the airplane and had been behind it for a while. That means less time to do your normal procedures putting you further behind. That raises stress and causes mistakes. That cycle feeds back on itself making everything worse.

They'd have needed the mental bandwidth to notice on the EICAS display that the spoilers weren't deploying to even know to manually trigger them. Given how far behind they were noticing that would be highly unlikely. Under high stress you revert to your training or habits and manual spoiler deployment is just not something you need to do.

Their bank angle (for lack of a better term) was probably not enough to notice unless they had the mental bandwidth to pay close attention.

This is a common thing in these sorts of accidents: if you have the mental bandwidth to deal with these problems you'd have been properly setting yourself up for landing 30 minutes before you started and you wouldn't be in this mess to begin with.

This also represents a safety margin during normal flights: If everything is done by-the-book and going well then you are calm, collected, and you have the mental resources available to do quick instrument scans after touching down and potentially notice spoilers did not deploy - and you have the extra runway to account for the few seconds of delay it takes to notice then manually deploy them.

No you must pass the stabilized gate well before minimums; legal requirement is usually 1000ft above the airport for IMC (instrument conditions), 500ft for visual conditions. AFAIK airlines can set higher minimums and may set other configuration gates (eg 1500ft gear must be out, flaps in landing configuration).

To be stabilized you must be lined up laterally (eg localizer captured) and on glide slope (vertically aligned). Airspeed must be Vref +/-10, final landing configuration (flaps, gear, etc), sink rate correct (<1000fpm), power set (not idle), and all checklists complete.

Typically the pilot monitoring should make a callout for this (eg "Approach") and the pilot flying responds ("stabilized" or "unstable, going around").

The "minimums" callout is to verify that you can see the runway sufficiently to land. The exact requirements vary - a Category I ILS you can go down to 200ft without seeing the runway. A Category IIIb ILS is 50ft. Technically Category IIIc allows 0 so has no decision height and requires no "minimums" callout but I don't know of anyone crazy enough to allow this - you wouldn't be able to taxi off the runway with zero visibility.

The stabilized approach gate is a performance & configuration check. Is the aircraft configured for landing and on the correct performance profile with the expected automatic guidance?

Minimums callout (DA/MDA) is a visibility check. Can we see the runway to whatever degree our approach requires?

btw: If you are curious the various ILS categories impose performance and redundancy requirements on both aircraft and the airport ground equipment. Things like backup transmitters, self-monitoring to catch drift, battery backups, etc.

Advice I've seen many experienced captains give when you're FO and captain is fixated on landing: declare going around to tower. It avoids a fight over controls or the captain trying to override you; in that moment they're unlikely to jump on the radio and say "no we aren't".

YMMV though, I'm not an ATP.

AFAIK all Part 121 Passenger operations in the US (and most worldwide) have a no-fault go-around policy. Most have eliminated even the minimal requirement to denote a log entry as to the reason lest that make pilots reluctant to do the right thing. Some airlines even have monitoring programs and will penalize pilots for not going around when they should even if they save the landing. They don't want a bad habit to develop (normalization of deviance) because some day the holes in the swiss cheese will line up and the pilot won't be able to save the landing - and by then it will be too late.

Part 121 Cargo and Part 135 Charter are ... another story. Quality of training and procedures vary a lot. Some are run about as well as the Part 121 Passenger operations. At others a go-around is a career-limiting move.

I do not know how 21Air operated - leave that to the NTSB to discover - but it would not surprise me whatsoever if Amazon leans heavily on their contracted ACMIs and yanks contracts for delays. A go-around means an extra 15 minutes (give or take) and Amazon cuts their logistics schedules razor thin so they don't have to pay for extra labor. A 15-20 minute delay in unloading the airplane can mean the sorting center staff and delivery trucks sit idle (though it wouldn't surprise me if they just stiff the delivery contractors for the wasted time).

This isn't necessarily done with ill intent - the middle managers at Amazon are just chasing their numbers and an operator that prioritizes safety will inevitably have worse on-time performance. As is often the case these days outsourcing / contracting can end up being a race to the bottom even if no one intends it that way. FedEx Ground is all contractors who bid on routes. If you ever wonder why the driver throws your package or leaves it in your driveway: they had to be the lowest bidder to get the contract and that means X deliveries per hour or they lose money. It just so happens that with air cargo operations this kind of pressure can easily lead to an accident.

Pilot here but not ATP or Jet rated.

When you try to land with too much energy the airplane refuses. When you get within a wingspan or two of the ground then ground effect starts giving you more and more lift. That plus excess speed means the airplane simply will not come down.

To force it down you lower the nose but that can end up castering on the nose wheel, starting a PIO event (pilot-induced oscillation), or as in this case the left wing just refused to stop flying. The "quartering tailwind" is a red herring. The jet was well within its tailwind limits - most of the wind was crosswind at that point and the tailwind contribution wasn't anywhere near enough to explain what happened. When you get above glide slope things get worse as you now need to lose altitude but that increases your speed. Even if you get the speed under control if you come at the runway with a 1700-2500fpm descent rate inertia can slam you into the runway.

They were coming in with way too much speed. They leveled off and got above glide slope because they were trying to bleed off enough speed to get within flap speed - flaps give you more drag which they desperately needed.

I made the transition this year into a much higher performance airplane and even going from a Cessna 172 to an A36 TN Bonanza the difference is stark. You must be way further ahead of the airplane in the Bonanza or you will find yourself screaming into the airport at 170kts when your landing speed is more like 80kts. And discover you are above flap and gear extension speed with all power taken out - thus without a good way to slow down.

Transport category jets are that times 100. You absolutely cannot get behind the aircraft. You plan your descents. You begin them much earlier. You pull power earlier. You add drag before speed runs away.

Above all else when you're barreling in 40kts above landing speed you call a go-around and try it again. It is way too late to fix it.

This accident started 30 minutes before they touched the tarmac. A complete failure of planning, of execution, and of ADM (to admit the problem and go-around).

Spool up time is 8-10s on high-bypass turbofan engines. They tried to go around maybe 1000ft from the end of the runway? It was far far too late to even try it at that point.

Sadly if they had made the call earlier they were going so fast they were basically at rotation speed when they touched down so could have just pulled back and gotten into the air.

They landed flat (and the left wing refused to come down) because they tried to force the plane onto the runway. That just doesn't work. The wings are creating too much lift when you're that fast.

Disclosure: Pilot but not ATP or Jet rated.

No, the left main was not on the ground after touchdown for some time. The aircraft will not auto-deploy the spoilers nor autobrake until it senses weight on weels. It also locks out the thrust reversers. All for obvious reasons.

The left wing was lifting because they came in way too fast. 30-40 knots above final approach speed. That's why they landed so flat - if they had assumed correct flare AoA the airplane would have flown away from the runway.

This is the definition of trying to "horse it onto the runway".

Disclosure: Pilot on small GA aircraft but not ATP and not jet rated so YMMV. FWIW small airplanes are the same: if you're too fast they don't want to land. Bad things happen when you try to force them.

You aren't wrong - the loan itself can be secured against machinery. But you will still be forced to sign unlimited personal liability for the loan itself unless the business is already well-established and profitable in which case they'll take it out of the business instead.

If the business fails the bank will pay someone to come take the machines away then dump it at the nearest auction. If something happens to the machine no one involved cares because you eat the liability (good luck proving otherwise when you're broke).

($LOAN_BALANCE - $AUCTION_PRICE) + $REPOSESSION_FEES + $AUCTION_FEES + $LOAN_DEFAULT_FEES = $YOUR_LIABILITY.

If you dig into the stats actual startups and small businesses mostly don't use any government small business programs. The few that do get used are most often gamed by much larger companies who "contract" with RandomJoe Inc who exists only to claim to be a small business.

Yes that is technically true. In theory you might be able to get some damages from them and even from Starbucks. But Starbucks would be within their rights to ban you permanently.

You could try to go after YouTube but expect to be permabanned from all of Google. You probably signed away your right to sue anyhow with some YT/Google TOS update.

Some of us have been predicting this for a while.

People with an axe to grind or states with an agenda are already devoting tremendous effort toward affecting LLM models and it is very difficult to determine real from astroturf for humans let alone an LLM trying to train.

Much like PageRank now that the cat's out of the bag all the current approaches may prove to be useless in the long run.

It's just hyperbole.

When parts spin that fast centrifugal force becomes a serious problem. Everything is a spring, nothing is actually 100% solid. Anything you make that spins that fast will at minimum grow larger in the direction of centrifugal force and shrink in perpendicular axis. If you don't account for that stretching and shrinking things like turbine blades will end up scraping the walls of the enclosure at speed.

Even minor variations in weight get multiplied and create exponentially higher stresses on the part. If you don't have the right alloy with the right hardening/annealing parts will rip themselves apart from attempting to support their own weight against the centrifugal force.

There's a reason modern high-bypass turbofan jet engines use monocrystaline blades because growing a single crystal of such size is the opposite of easy or inexpensive. Plus in the core you are dealing with so much heat no alloy exists that can withstand it for long so you have to machine cooling channels inside the blades (which have complex curves) to keep them from getting soft and flying apart.

edot covered this better than I could! You're quite wrong. It all depends on volume.

SBA loans are just regular loans from a bank, except with government backing.

You need a high credit score (680 at least) to even have a hope and 10% cash to put down if not more.

Unless you can prove experience managing a business forget it. You have to demonstrate other outside income (hope your spouse works a good job) or enough cash in the bank to cover living expenses for a year or more.

If the business is going to be a new venture you have to put together financial projections that demonstrate how you are going to start making money and it had better be quickly. You will not get 2 years to ramp up. And if you fail to meet projections they can call in the loan.

Oh and by the way: you must sign an agreement to take unlimited personal liability for the loan. So if the business fails they get to take away your savings, retirement, even your house. In fact if you don't have significant assets they will put a lien on your house as part of the loan closing!

In China if you want to start a factory in an area the national government lists as desirable the state-owned bank will almost shove money into your hands. Repayment timelines are extremely generous. You mostly don't take on personal liability - instead they focus on the assets, land rights, etc. That is if the business starts to fail you will own machinery, a lease on the land, and/or a factory building so they are content to secure the loan against those things.

When the state bank underwrites your loan in China they only care that your project is technically viable and you have some kind of plan. They assume you will find a way to be profitable and worst case they can take the factory away from you and give it to someone else. As long as your plan makes sense - if your plan says you're going to make robot arms but your plan doesn't mention buying any CNC machines or hiring any electrical engineers you will have difficulties. And if you want to build a factory to make lathes expect serious pushback - the Chinese government considers that sector to be "over-capacity" so they are reluctant to finance new factories for such things.

Not that it matters because unlike the USA if you aren't a Chinese citizen then you can piss right off because you aren't going to be approved for anything and you aren't allowed to own property anyway. Not that any court would ever side with you in any case either.

The entire philosophy is different and I'm saying we should adopt the Chinese philosophy. Instead of letting risk-adverse private banks make the decision the government should make the decision. And instead of focusing on credit score and making you sign an unlimited personal liability contract - do the opposite and secure the loan against the actual factory, machinery, and assets. Build a network of such so if a business fails you can turn around and offer it to the next suitable applicant who can bootstrap their business instead of selling everything for pennies on the dollar at auction.

It is not a legal process. It is Google's process designed to minimize their involvement to the maximum degree possible.

When some random person copyright strikes your YT account you have no rights because it isn't based on the law. Its the equivalent of someone going to the manager of Starbucks and falsely saying you are harassing them, then the manager tells you to leave or they'll call the police. One private party told another private party you are a bad person and the private party in control punished you.

If memory serves the whole system came about way back because the big media companies and record companies got together to sue YT after google acquired them. So you might say the system was designed to let purported copyright holders act arbitrarily on purpose.

It isn't just about that. You need industrial policy. And not just stuff like the CHIPS act.

In China a small outfit can get financing and open a factory anywhere.

You can't do that in the USA. You are too small for the lenders or investors who do such things to care yet too risky for traditional financial institutions to risk anything on you.

If I want to buy a couple of CNC machines and start making a product in my garage I have to hope I have enough room on credit cards to do it because I cannot get the money from anyone. Doesn't matter if I have a good idea. Doesn't even matter if I have some initial customers/orders.

If the government is going to piss away money then at least piss it away on that sort of economic activity. If you can present a coherent business plan or product design then lend people the capital secured by the equipment and/or IP with generous repayment terms. Set progressive milestones to unlock additional financing... for example give a gov backed credit account at SendCutSend. When you have an engineer's report on the prototype to turn in you unlock financing to order your first CNC machines. Develop a pipeline. A script to follow. Something a person can follow to get big enough to become a real business.

Grant time to pivot if necessary. If that doesn't work then ultimately the government takes possession of the equipment. Make it clear so long as you return everything in good working order then in X years you're eligible to re-enter the program. Then hand that equipment over to the next person in line.

I think the argument is that you should't be forced to pay that cost for all writes even if only some require it.