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nabla9

Garmin Autoland is emergency only autoland.

Not to be confused with CAT II/III autoland used in normal operations.

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Btw, here's probably the only actual cat IIIC landing video on YT:

https://youtu.be/gthcuZV8agI

That's terrifying. Cool, but terrifying.

For anyone else wondering what "emergency only autoland" means:

From Wikipedia: "The feature is activated by a guarded red button on Garmin G3000 NX avionics, evaluating winds, weather and fuel reserves to select a suitable diversion airport and taking over the aircraft controls to land, it advises the ATC and displays instructions to occupants."

From the Garmin marketing site [1]: "Garmin Autoland. It takes complete control of the flight to land the airplane in an emergency where the pilot is unable to fly1."

I'm not exactly sure if this is the correct reference for CAT II/III autoland, but seems like the purpose of CAT II/III autoland is to land and aircraft when the pilot would otherwise have a hard time manually landing due to weather conditions (ie. limited visibility) [2]. But if someone has a more accurate description, please correct me!

[0] https://en.wikipedia.org/wiki/Autoland#Emergency_autoland

[1] https://www.garmin.com/en-US/autonomi/

[2] https://en.wikipedia.org/wiki/Instrument_landing_system#ILS_...

Edit: Just to clarify the reason for posting this versus just relying on the text in the press release, I was under the impression the announcement was for some fully-automated flight control system (ie. take off and landing without a pilot on board, a la self-driving cars) based on the press release not mentioning why the system would be activated.

CAT II/III can land with limited visibility.

CAT IIIc is interesting because there is no decision height and no runway visual range limitation. Pilots can approach and land completely blind without flying with the stick at all. https://www.youtube.com/watch?v=gthcuZV8agI

Big airports with CAT IIIc can stay open for CAT IIIc available aircraft in all visibility conditions.

And then you have to taxi in that pea soup. :)

I think they send somebody with light to help you if you get lost.

Cat II/III use ILS which send out signals on the runway(s) in question. IIRC, those signals need to be monitored to make sure they're with-in certain tolerances because II/III is used in minimal visibility conditions, so there's very little time to correct things at the last minute. It's about trusting a whole bunch of equipment to work properly because you're basically flying with a blind fold on otherwise.

This Garmin G3000-based system primary uses GPS/WAAS (and perhaps VORs) to get location data, so accuracy may not be with-in necessary tolerances for day-to-day use, but it's better than nothing for emergencies.

The marketing videos say the airport needs to have a published GPS approach.

GPS WAAS is good only down to 200 and 1/2 (200’ above ground cloud base and 1/2 mile visibility underneath)

Cat II ILS can go down to 100 and 1200RVR (100’ bases and 1200’ of runway visual range)

Cat IIIc can go down to 0/0.

200 and 1/2 is perfectly usable for most day to day weather and is certainly good enough for unexpectedly incapacitated pilot.

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