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Old 11th Mar 2019, 17:04
  #395 (permalink)  
Join Date: Sep 2016
Location: USA
Posts: 509
Originally Posted by GotTheTshirt View Post
Is there some logic in having a couple of switches operating in the opposite sense to the rest ??
Yes. The scheme is, on any vertical surface (like the instrument panel, or a wall) up = on, same as any switch in the rest of the world. On any horizontal surface (center pedestal, or overhead) forward = on. For the center pedestal, the forward = on scheme elegantly matches what you're used to (toward the top of your eyeball = on). But I've always thought that that's a stupid application on the overhead, which gives the feeling of upside down switches since it reverses the "toward the top/bottom of your eyeball" relationship, and instead it should just be treated like a wall.

And the 737 seems to have very few switches in places that aren't the overhead, so the overhead upside-down scheme prevails. But the stab cut out switches are on a place where the normal (up = on) scheme is in place.
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