A Horizon Indicator is a gyro in an aircraft. It’s purpose is to give you a visual of your aircraft in relation to the horizon. Today these are getting replaced with digital displays. The older gyro ran off a vacuum system which spun the gyro. That whirring you hear in an airplane when the switches go on are the gyros spinning. When the aircraft banks or pitches, the gyro instruments did not, giving you an indication of your attitude relative to the horizon. The horizon is indicated by a thick white line that goes horizontally across the gauge. On the newer gauges above this line is blue, representing the sky, and below it brown, the ground.
However, the original gyros did not have the colours. Just a white line, black above and below. I’m sure you’ve all heard about the Day The Music Died, if nothing else in the song American Pie. Buddy Holly chartered a small aircraft to get him to the next gig. Waylon Jennings gave up his seat for a fellow band mate, saving his life and enriching mine. Well this aircraft had the black on black directional gyro. As the pilot took off he was soon in zero visibility. The problem with this gyro was once you got into a bank greater than 45 degrees, it was hard to tell which side of the horizon line meant ground and which meant sky. Most crash experts attribute that crash to a inexperienced IFR pilot and that particular gyro.
I was thinking how I could make this blog have meaning but have decided not to. There’s lots of thoughts in my head about how it doesn’t matter if you know the general attitude you are in, if you don’t know up from down. Or the importance of having a good instrument. Perhaps I could have tied it in to a “stitch in time saves 9” message. If the pilot hadn’t got past 45 degrees of bank he might never have become disorientated. I will spare you all of that blah blah blah.
I found one of these particular gyros today. I walked into a hanger looking for a gift for someone who built an aviation room. I found the perfect gift.
Besides, what more does a blog need that has aircraft instrumentation, Buddy Holly, and Waylon Jennings in it?
If you read this far, thank you.
Tris.
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