Old 10-13-2018, 03:35 PM
  #4  
vessbot
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Joined APC: Jan 2017
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I like the old way much better. And I've got a lot more instrument time looking at a new type (sky pointer) panel, so you can't accuse me of favoring familiarity. I think the sky pointer is downright stupid, for some objective reasons.

First, it violates a basic general scheme that tick marks are fixed to some outside-world fixed reference scale, with a single pointer representing the value of interest (or the thing we're controlling) and we try to control it to go the tick mark we want. Look at anything else: altitdue, heading, vertical speed, air speed. With the sky pointer that's backwards: we're taking the tick marks around with us, and the "outside world" fixed reference is the single marker. And that by itself wouldn't be so bad, if it wasn't in combination with the second general scheme that is violated:

At the center of the whole attitude indicator (old-style mechanical and sky pointer EFIS alike) is the airplane symbol, the thing that's locked to us, the pilot, and airplane. All around it (again, in both systems) is the "outside world:" the movable ground/horizon/sky that we're operating within. We fly our little airplane symbol around the "outside world" on the screen, a duplication of the real airplane and real outside world. OK, good so far. Now bring the sky pointer into it... at the top we have the sky pointer (representing the outside world) INSIDE of (and closer to the airplane symbol than) the bank angle tick marks that are fixed to the airplane. It's an inversion, or outside-in. It would be more intuitive and easier if the the airplane-fixed element was on the inside, close to the airplane symbol; and the outside-fixed element (the sky pointer) on the outside

It's a crap system. Maybe it was designed by human factors eggheads that have done the hard work to find it's really a better system despite my criticisms, but I think it's likelier that it was done for a dumber reason. (It wouldn't be the first ergonomic/human factors atrocity to make its way into a cockpit.) What I keep hearing is that it shows you a sky pointer that you know you're supposed to roll toward if you get disoriented... but guess what, the old style attitude indicators have one too, just on the outside where it belongs!

Last edited by vessbot; 10-13-2018 at 04:00 PM.
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