Runway Width Illusion

There is a fairly common illusion that can make landing more difficult at unfamiliar airports, especially at night. The illusion occurs because we tend to get used to a certain runway width.

When approaching a runway that is narrower than you are used to, you may feel like you are higher than you really are.

This happens as a simple matter of perspective. Your brain uses the size of common objects to interpret your distance to them. However, runways are not common because every is a little bit different. Your brain sees the narrow runway and thinks it is a runway of normal width, only farther away.

Of course, this can be very dangerous as you may contact the runway unexpectedly while you believe you still have some distance to descend. You may land in a flat or even nose down attitude. I have seen students suffer from this illusion many times. Typically, they realize it about one second before touchdown, when I grab the yoke and pull until the plane is in the correct landing attitude.

The illusion also works the other way too. If you are approaching a wider than usual runway it will appear to be closer than it really is. This is not as dangerous as a narrow runway, but still worth avoiding.

As I said above this illusion is far more common at night when it is difficult to see and the runway lights provide most of the information about your height.

How to avoid this illusion

There are several parts to avoiding this illusion.

  1. Briefing. When flying to any airport you have a duty to become familiar with all information relevant to the flight. This includes the width of the runways you expect to land on. Don’t just ignore this detail.
  2. Know the illusions. This illusion is very common at night. It is something you should be prepared for and looking for as you approach any runway at night, especially a narrow one.
  3. Correct immediately. If you believe that you may be experiencing this illusion during landing, correct immediately! Don’t wait to be sure. Just pull back on the yoke to landing attitude and either go around or touch down. If you were wrong, and you really are high above the runway it is often better to go around.