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Comment by jacknews | Hacker News Reader

"Now it would be natural to think that with the sophisticated autopilot systems that we have today, a plane could land itself quite easily. And that’s kind of true "

Indeed, I believe a substantial portion of commercial flights are actually landed automatically (contrary to what the article claims).

Bravo for doing it autonomously though, it's obviously the next step.

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Contrary to popular belief, autoland systems are not used that frequently, at least in the US. Typically the only time autoland is accomplished is when the pilots or aircraft need a practice run for currency or weather conditions actually dictate its use. Autoland is required for CAT II and III approaches on the aircraft I operate. CAT II weather minimums are 100-200 ft decision height and 1,800 RVR for many operators. CAT III is even lower. If the weather is greater than that autoland typically is not going to be used.

This system is very interesting though for small aircraft. As the article states, small aircraft often fly into small fields that may not have as much precision landing equipment on the runway. I could see this system being an excellent augmentation system or an additional input in the pilot’s planning of the approach and landing.

[EDIT] clarity about CAT II and III

You can tell/guess sometimes. An auto landing would feel kind of rough. The reason for this is that a rough landing removes enough energy to make a bounce unlikely and that would be undesirable as recovering from those is a bit tricky. The gear can handle it. So they intentionally plant it down firmly instead of "greasing it in".

Takeoffs and landings are pretty much the only point where commercial aviation involves any manual flying at all these days.

Autonomous flight will likely go through years of testing and scrutiny before it will be considered safe. But technically it's not fundamentally any harder than a self driving car. I could see this help reduce work loads for pilots short term.

There is a huge fundamental difference - you can't stop on the curb and send SOS when something breaks.

There's no margin for error.

Of course there are margins for error. They're just smaller.

Small aircraft also tend to have less experienced pilots, so more help managing the complexity of the landing could reduce incidents like this one in Houston (stall leading to crash during go around):

https://www.flyingmag.com/aftermath-cirrus-crash-june-2016/

> 50 ft decision height

What does that mean?

The height at which the pilot has to abort the landing attempt if they can't visually confirm that they're correctly set up for landing.

I was actually mistaken. That’s for a CATIII. CAT II is actually 100-200ft. That’s how low the reported cloud bases can be.

The article doesn't spell out why Category IIIc (the mode in which the "decision height" is zero and the computers will put the plane down even if there is literally no visibility at all) isn't used in practice. The reason is: ok, now your plane is on a runway, we all agree that's good, but what next? You can't see, that's why you need Category IIIc rather than just Category IIIb which is sometimes done in bad weather. So you can't taxi the plane off the runway safely. Your ground controllers can't see you either. This is strictly better than not being able to land, but that's all.

So Cat IIIc (and to some extent even other Cat III landings) come into their own when the busiest airports can safely handle ground operations in all weathers, which may never happen.

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