From: Paul Hirose (no email)
Date: Thu Feb 03 2005 - 02:19:33 EST
George Huxtable wrote:
>
> Isn't it true that magnetic bearings also enter into the labelling of
> runways?
Correct. For example, a runway oriented to 60 degrees magnetic would
normally be designated Runway 06 or Runway 24, depending on which
direction is in use (normally determined by the wind). With two
parallel runways at the airfield, they'd be called 06L and 06R, etc. I
think letter C can be used too if there are three parallel runways.
Los Angeles International has *four* parallel runways, so one pair's
numbers are fudged a little to eliminate conflict: the runways are
called 06L, 06R, 07L, and 07R (or the reciprocals). In reality, all
four are parallel to better than .1 degree.
I doubt that runway designations are changed if the magnetic variation
changes at the airfield. The 10 degree numbering increments so coarse,
the situation should rarely occur. If it does happen that a number
change becomes appropriate from a mathematical standpoint, I'm sure
the practical difficulties of repainting the runway numbers, revising
publications, etc. would take precedence.
For an instrument approach you do need accurate runway heading, but
that's found in the published approach procedure.
|