.

Besides, how do runways get their numbers?

Plainly put, airport runways are numbered according to compass bearings. This means runway numbers are based on the compass with 360 representing north, 90 representing east, 180 representing south, and 270 representing west. Runways are numbered between 01 and 36. The second number differs by 18 or 180 degrees.

Furthermore, why do airports change runways? Wind shift - Aircraft need to land and takeoff into the wind. Aircraft normally land there to the west because of the prevailing onshore breezes. However at night around midnight, they will shift the landing runways so that aircraft approach from the west flying over the water and land to the east.

Keeping this in view, what do numbers on a runway mean?

All runways are numbered based on the magnetic azimuth (compass bearing) in which a runway is oriented. So if you're on runway 9, then you're heading east (90 degrees on a compass). Runway 36 means you're moving north, and so on. Most runways can typically be used in either direction, depending on prevailing winds.

How do airports decide which runway to use?

Weather, in particular wind speed and direction, is generally the main factor in determining which runways are in use at an airport, in which direction aircraft will take off and land and which flight paths are used. At all times, the safe operation of aircraft will be the primary consideration.