Due to the shift of the magnetic north, the name of runway 02/20 at Brussels Airport will change into 01/19. That may seem strange, but there is a clear scientific explanation for it.
All over the world runways bear a number from 01 to 36, depending on their direction with respect to the compass: the number 09 stands for the east (90°), 18 for the south (180°), 27 for the west (270°) and 36 for the north (360°). As runways can be used in two directions, which are 180° apart, they have two numbers that indicate both, with a difference that is always 18. That’s why runway 02 is also runway 20 in the opposite direction, and runway 07 is also runway 25.
The compass aligns itself with the magnetic north, the location of which is not completely stable. The magnetic north of our planet shifts a bit each year, so that at a certain moment 11 degrees becomes 10 degrees, and a few years later even 9 degrees. So eventually some airports find themselves with a runway whose name that was given years ago no longer matches today’s reality of the compass. These annual changes are small, but Brussels Airport has now reached a point where 02/20 needs to be renamed 01/19.
This official name change will happen on the night of 18/19 September 2013. Although this is not the first time a runway needs to be renamed for the same reason at a large airport, it is rather rare and such changes are not much documented. The two other - parallel - runways at Brussels Airport adopted new names in the early 1970s. They used to be 08L/26R and 08R/26L. And now it already looks like they will need to be changed to 06/24 in a few years’ time.
Putting a runway name change into force requires more than just painting the new number on both sides of the runway. The fact is that the name of a runway appears in hundreds if not thousands of official documents and on plans, and they all have to be updated. Since any misunderstanding about the exact use of a runway could have serious operational consequences, this kind of name change must be carried out safely and flawlessly, in close consultation with all parties and authorities concerned.
A dedicated project team maps out all the possible ramifications of the change. It is listing the effects on the activities of the respective companies and departments at Brussels Airport. As this has a huge impact for air traffic control management, Belgocontrol also played a vital role in this project. At the moment there are few documented cases that can serve as references. Our experiences with the name change will therefore be thoroughly documented so that they can be useful in the event of subsequent name changes.
During the night of 18 to 19 September the name will be changed in all the databases used for aeronautical navigation all over the world. At the same time all the signs at the airport will be changed too, and the lettering on the runway itself will be repainted. To avoid any misunderstanding: tomorrow’s 01/19 will be the exact same runway as today’s 02/20: it will only wear a new number painted at both ends. This name change has no impact on flight routes or preferential runway use.