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Comment by f1shy | Hacker News Reader

There are 3 different hydraulic system plus one electric that can be operated out of a battery… anything is possible, but it seems until now they failed to lower the gear.

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Something else that may be a factor, a lot of Asian carriers teach their pilots to use auto pilot for landing. American pilots almost universally SOP do not use auto pilot when landing. It's possible the South Korean pilot was using auto pilot to land, forced to do a go around, but wasn't in the habit of manually configuring the plane for landing. That's how the flaps and the gear were both missed. He assumed autopilot etc was handling that.

I think in the cockpit voice recording we are going to be hearing the sirens going off about no landing gear and those guys were just not paying attention.

That would be a tragic void in training and procedure. I hope for the sake of the families involved that it doesn’t turn out to be something so avoidable in practice and foreseeable in the carriers operating procedure.

I’m afraid it will be something like that…

There are numerous past examples of this sort of thing. Automation in aviation is really hard to get right. If the automation can fail then the pilots need to be able to perform whatever it was going to do. If the automation fails rarely then the pilots may not get enough practice. But if the automation normally does a better job than the pilots, there’s a tension with letting them get more practice on real flights.

A recent(ish) example is the Asiana crash in SF. They had pretty much perfect conditions for a hand-flown visual approach, but they were out of practice, got behind the airplane, and it snowballed.

There’s an excellent lecture about this called Children of the Magenta Line. The magenta line being the flight path or direction indicator on an autopilot, and the discussion is about pilots who constantly reconfigure the autopilot to direct the plane instead of just taking over. https://youtu.be/5ESJH1NLMLs

Which aircraft have flaps or gear controlled by an autopilot? I'm just an armchair "Air Crash Investigations" fan, but I've never heard of any aircraft where either flaps and gear would be automatically controlled by their autopilot. Speedbreaks / spoilers are usually armed and moved automatically on landing.

There's also a backup manual gear release. But from the degree of control over the airplane demonstrated during landing, it seems likely they had hydraulics.

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