Switches - which way is on?
Join Date: Oct 1999
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... but a Canadian or US domestic light switch is 'up' for closed circuit, so from a North American point of view, mag switches (in Cubs and Citabrias) are installed 'upside down'.
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Join Date: Jul 2000
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The more information that is posted in reply to my question, the more I am beginning to think that switch position doesn't have a safety background at all.
Thanks for all the input
Thanks for all the input
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Hi, 4Greens; when I was an apprentice and a trainee pilot we were told that "up is on" was a safety feature, based on the idea that a quick downward swipe could be used to turn off any switch in an emergency. The idea became an international standard for aviation. American household switches apparently work the same way for the same reason, but British and Australian switches treat "down" as a positive, "on" motion and "up" as a negative and therefore "off" motion.
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Good point but as you say UK and AUS use different positions. They drive on different sides of the road and the maritime buoyage system is also the other way round. Is this really safety on an international basis?
I remember one of our Britannias in IAS, a 307, G-ANCD had switches that worked in the opposite direction to all the other Brits I flew - ie UP for ON. The flight deck was also finished in light grey rather than the usual matt black. The aircraft was built for the US airline Capital, but was never delivered to them.
