What Does “Maintain Runway Heading” Mean to YOU?
When leaving from a non-towered airport, we are taught to add the crosswind correction required to remain aligned with our departure runway, but what does it mean when Tower tells us to “Maintain runway heading”? As it turns out, something completely different.
First of all, let’s go to the Aeronautical Information Manual (AIM.) In the Pilot/Controller Glossary, we read:
RUNWAY HEADING− The magnetic direction that
corresponds with the runway centerline extended, not
the painted runway number. When cleared to “fly or
maintain runway heading,” pilots are expected to fly
or maintain the heading that corresponds with the
extended centerline of the departure runway. Drift
correction shall not be applied; e.g., Runway 4, actual
magnetic heading of the runway centerline 044, fly
044.
That means no crab, no crosswind correction, just the magnetic heading of the runway. Yes, any wind will blow you off the extended centerline, but that’s ok- so will every other plane taking off behind you, and as a result, everyone will stay in-line.
So, here’s the next question- if you are taking off from a runway, what is the magnetic heading? There are several different sources, but the airport diagram has that information right on it. For example, if you look at the diagram for Charleston International (KCHS), you will see that the actual magnetic heading for Runway 33 is 335.5, so that’s the heading you would hold, without wind correction (OK, the .5 isn’t as crucial.)
There’s an even easier way- once you are lined up on the runway, just fly the heading you are on, until you get new instructions.