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A comment on Boeing 777 departing Dubai nearly had a major incident after takeoff. Parent comment

Re:Boeing 777 departing Dubai nearly had a major incident af... by throwanem on Saturday January 01, 2022 @06:35PM (#29764040)
The takeoff isn't directly automated, but there's a system called the "flight director" [1] that provides indicators on the pilot flying's display that correspond with a configured trajectory. In this case, it sounds like the flight director was badly misconfigured and the pilots not only omitted to reconfigure it, but followed the erroneous indication far past any point at which it was remotely reasonable (or remotely safe!) to do so.

[1] https://en.m.wikipedia.org/wiki/Flight_director_(aeronautics...

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Re:Boeing 777 departing Dubai nearly had a major incident af... by encoderer on Saturday January 01, 2022 @07:05PM (#29764242)
So this is the airline equivalent of Michael Scott following his gps into the lake?

Insane

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Re:Boeing 777 departing Dubai nearly had a major incident af... by throwanem on Saturday January 01, 2022 @07:34PM (#29764452)
I mean, you say that as if it were a joke, and yet I can't fathom any other explanation for this kind of event but that the pilot flying assumed the automation "knows where it's going". Unfortunately, without Rainn Wilson as the PNF...
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Re:Boeing 777 departing Dubai nearly had a major incident af... by lisper on Saturday January 01, 2022 @08:17PM (#29764719)
Private pilot here. Yes, that is exactly right.
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Re:Boeing 777 departing Dubai nearly had a major incident af... by MertsA on Sunday January 02, 2022 @07:59AM (#29768370)
For context on the reference to following gps into a lake: https://youtu.be/DOW_kPzY_JY?t=20
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Re:Boeing 777 departing Dubai nearly had a major incident af... by _moof on Sunday January 02, 2022 @04:35PM (#29774191)
It is precisely that, and it is inexcusable.
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Re:Boeing 777 departing Dubai nearly had a major incident af... by MertsA on Sunday January 02, 2022 @07:56AM (#29768357)
Why does it not have basic sanity checking to make sure the configured flight path is not going unreasonably close to terrain? Is it solely controlling heading and altitude or does the flight director incorporate waypoints and topology?
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Re:Boeing 777 departing Dubai nearly had a major incident af... by throwanem on Sunday January 02, 2022 @10:29AM (#29769445)
It's not controlling anything, just providing steering cues for the pilots along whatever route it's set up for. Setting it up for the flight's intended route is a checklist item, which appears not to have been performed on this flight. Also on the checklist is identifying the correct airspeed for current conditions, called "Vr," at which to "rotate" and bring the aircraft off the ground during the takeoff roll.

Actually doing that is a memory item, intended to be prompted by a "Vr" call from the pilot not flying. As far as I know it's not yet clear whether the PNF gave that call, but the PF certainly waited to rotate until well after reaching Vr. This is where the "sanity checking" appears to have failed, with the PF heeding the misconfigured flight director when it disagreed with other instruments and the situation visible out the cockpit windshield.

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Re:Boeing 777 departing Dubai nearly had a major incident af... by aaronmdjones on Sunday January 02, 2022 @10:14AM (#29769314)
It's heading, altitude, and speed. For example, if you're currently accelerating to a target speed and climbing to a target altitude, it won't command you to pitch up so much that you stop accelerating.

The autopilot follows the flight director, and the flight director is dumb.

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Re:Boeing 777 departing Dubai nearly had a major incident af... by throwanem on Sunday January 02, 2022 @10:32AM (#29769474)
The autopilot wouldn't have been in use for the takeoff roll, though, would it? The question of automation smarts seems like a bugaboo in what I understand to be a highly manual flight regime.
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Re:Boeing 777 departing Dubai nearly had a major incident af... by aaronmdjones on Sunday January 02, 2022 @10:38AM (#29769531)
Correct, autopilot isn't engaged until at least several hundred feet AGL; varying by airline. Some airlines don't engage autopilot until reaching transition altitude or even cruise altitude. Still, the flight director is giving you the same information, and most pilots will just follow that because it's the most accurate way of getting you to where you need to go... if you've set it up correctly.
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