Meaning of numbers on airport runways

The digits on the two ends of the airport runway indicate the compass azimuth, which helps the pilot guide the standard when taking off.

All airport airstrips around the world are numbered based on the compass azimuth to inform pilots which runways to take off and land, according to Stantec. The number on the runway is determined by rounding the compass azimuth at one end of the runway and removing the last digit, meaning that the runways will be numbered from 1 to 36.

Many large airports have parallel runways that require more specific numbering.

The opposite end of the runway forms a 180-degree angle with the other end, so the head is always numbered 18 versus the number at the other end. For example, the 9-27 runway has east-west direction. If you are on runway 9, you are going east (corresponding to 90 degrees on the compass).

Most runways can be used in both directions, depending on the wind direction. Each end of the runway can be identified separately. An aircraft taking off east on the runway 9-27 will leave at the beginning of 9th.

Many large airports have parallel runways that require more specific numbering. For example, Logan International Airport in Massachusetts, Boston, USA, has two parallel runways numbered 4L-22R and 4R-22L. The letters "L" and "R" refer to the corresponding position on the left (left) or right (right). If the airport has three parallel runways, the middle runway will add C (center) after the number.