4 ms·

The tech is still interesting, even if similar things that are used even in non-emergency scenarios have existed in large jets for a few decades. The one thing

The tech is still interesting, even if similar things that are used even in non-emergency scenarios have existed in large jets for a few decades. The one thing I don't understand is if it always just relies on WAAS and GPS no matter what, or, if depending on the runway it chooses to land, it may use something like an ILS.

tialaramex 7y ago
It won't try to do ILS. I think the issue is that where GPS is available it can definitely put that plane down. Maybe it's not the world's greatest landing due to GPS inaccuracy, not right on the centre line, tries to put the gear through the floor - maybe the airframe ends up totalled, but if every passenger on the plane walks away it's a huge success given the pilot was incapacitated. Whereas for ILS that gets you down under clouds in mediocre weather, all lined up properly, but (except in airports with Cat III ILS) it doesn't actually put you on the ground. With a trained pilot in the seat that's not an issue, once they can see the runway they can do the rest, but this is for emergencies. As I mentioned in a previous HN item about ILS, these autoland systems don't get you off the runway. For a grave emergency (pilot dropped dead in flight with their spouse and two kids onboard) that's forgiveable, and this mentions that the product begins broadcasting that the runway chosen is now unusable (because your plane is now parked on it) but this is why Cat IIIc doesn't magically allow JFK to function normally in a blizzard. When the pilots still can't see the runway even after their plane lands on it, that's not useful for routine passenger flights.
- throw0101a 7y ago
  > I think the issue is that where GPS is available it can definitely put that plane down. Maybe it's not the world's greatest landing due to GPS inaccuracy, not right on the centre line, ... I wonder how this will change when the L2, L5, and L1C signals start becoming used from the GPS III satellites. Also, in the US, non-GPS/Navstar signals cannot officially be used for anything, though I think Galileo was recently (finally) approved by the FCC: * https://www.gsa.europa.eu/newsroom/news/fcc-approves-use-galileo-us https://www.gsa.europa.eu/newsroom/news/fcc-approves-use-gal... (The issue was something like: once officially approved, the frequencies in questions cannot be used for anything else, and are protected.)
- Animats 7y ago
  The system, which is from Garmin, includes a radio altimeter, a short-range radar pointed straight down. So it's not reliant on GPS for precise vertical position during landing. This allows the system to do a proper landing flare just above the runway.
throw0101a 7y ago
I ran across a report somewhere that more airports (in the US) now have RNAV approaches than ILS ones. ILS equipment isn't cheap, and so many places don't have it. But a lot of folks now have GPS, especially because of the ADS mandate, and so while most probably aren't IFR-rated, I'm guessing if you're flying a turboprop or Cirrus jet, they probably are.
- base698 7y ago
  I have a Garmin 530 and it's IFR rated, most of the 430s are too and relatively common in single engine planes. The ADS mandate was more for transponders. It does seem like a lot of airports have RNAV only and if they have an ILS they also have an RNAV.
  - throw0101a 7y ago
    I was under the impression that more that just having a magic box was needed for a plane to be IFR-rated.
    - base698 7y ago
      The GPS has to be rated, there are also requirements for the plane to fly IFR in 91.205: https://www.law.cornell.edu/cfr/text/14/91.205 https://www.law.cornell.edu/cfr/text/14/91.205 One mnenonic is GRABCARD Generator Radios Attitude indicator Ball Clock Adjustable altimeter Rate of turn indicator Directional gyro

tialaramex 7y ago

It won't try to do ILS. I think the issue is that where GPS is available it can definitely put that plane down. Maybe it's not the world's greatest landing due to GPS inaccuracy, not right on the centre line, tries to put the gear through the floor - maybe the airframe ends up totalled, but if every passenger on the plane walks away it's a huge success given the pilot was incapacitated. Whereas for ILS that gets you down under clouds in mediocre weather, all lined up properly, but (except in airports with Cat III ILS) it doesn't actually put you on the ground. With a trained pilot in the seat that's not an issue, once they can see the runway they can do the rest, but this is for emergencies. As I mentioned in a previous HN item about ILS, these autoland systems don't get you off the runway. For a grave emergency (pilot dropped dead in flight with their spouse and two kids onboard) that's forgiveable, and this mentions that the product begins broadcasting that the runway chosen is now unusable (because your plane is now parked on it) but this is why Cat IIIc doesn't magically allow JFK to function normally in a blizzard. When the pilots still can't see the runway even after their plane lands on it, that's not useful for routine passenger flights.

throw0101a 7y ago
> I think the issue is that where GPS is available it can definitely put that plane down. Maybe it's not the world's greatest landing due to GPS inaccuracy, not right on the centre line, ... I wonder how this will change when the L2, L5, and L1C signals start becoming used from the GPS III satellites. Also, in the US, non-GPS/Navstar signals cannot officially be used for anything, though I think Galileo was recently (finally) approved by the FCC: * https://www.gsa.europa.eu/newsroom/news/fcc-approves-use-galileo-us https://www.gsa.europa.eu/newsroom/news/fcc-approves-use-gal... (The issue was something like: once officially approved, the frequencies in questions cannot be used for anything else, and are protected.)
Animats 7y ago
The system, which is from Garmin, includes a radio altimeter, a short-range radar pointed straight down. So it's not reliant on GPS for precise vertical position during landing. This allows the system to do a proper landing flare just above the runway.

throw0101a 7y ago

I ran across a report somewhere that more airports (in the US) now have RNAV approaches than ILS ones. ILS equipment isn't cheap, and so many places don't have it. But a lot of folks now have GPS, especially because of the ADS mandate, and so while most probably aren't IFR-rated, I'm guessing if you're flying a turboprop or Cirrus jet, they probably are.

base698 7y ago
I have a Garmin 530 and it's IFR rated, most of the 430s are too and relatively common in single engine planes. The ADS mandate was more for transponders. It does seem like a lot of airports have RNAV only and if they have an ILS they also have an RNAV.
- throw0101a 7y ago
  I was under the impression that more that just having a magic box was needed for a plane to be IFR-rated.
  - base698 7y ago
    The GPS has to be rated, there are also requirements for the plane to fly IFR in 91.205: https://www.law.cornell.edu/cfr/text/14/91.205 https://www.law.cornell.edu/cfr/text/14/91.205 One mnenonic is GRABCARD Generator Radios Attitude indicator Ball Clock Adjustable altimeter Rate of turn indicator Directional gyro