As many of us have noted while pointed down our runway, there is a pretty good discrepancy between our 'official' runway numbers and what our magnetic compasses are telling us.

During the routine annual inspection of our airport just conducted by California DOT Aeronautics Division in early April, the inspector took note of this discrepancy.  For Runway 07, his reference compass read 77°, and his official report is expected to direct that we update our runway designations at the next painting.

For those a little rusty on this stuff (hey, that test was a long time ago, right?), runway designations are based on magnetic heading, rounded to the nearest 10°.  And magnetic compass readings differ from true heading by some variable amount depending upon your geographical position relative to the 'Magnetic North Pole', currently located approximately in central Canada.

This would be no problem were it not for the fact that the north magnetic pole won't stay put.  Over our lifetimes it has been gradually drifting westward, causing our local magnetic declination to decrease bit by bit as years pass (a compass here in SoCal will gradually read closer to true).  Currently, this drift (about 25 miles per year) causes a change in declination at our location of about 0° 5' per year, or a full degree every 12 years. 

To be exact, our current declination calculates to 13° 17'. This means our runway 07, which is laid at 90° true (or damn close), is now at 76.72° magnetic.  This pretty well matches the CALDOT inspector's 77° reading.

So that's the story. No one likes change, but we can deal with it.  I started commuting into Burbank when the ILS runway was 07, it moved to 08 about 1989 I think, and although it took a while to remember the new "name", it finally sank in.

            John Wilson

UPDATE:  At the Sept. 14th Board meeting it was decided to re-paint markings, but WITHOUT either changing the runway heading or re-adjusting the Rwy 07 threshold.  This was done because the possibility of alterations related to the proposed annexation creates too much uncertainty to deal rationally with marking changes at this time.

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Last modified: 7/27/08