ELI5: Explain Like I'm 5

Aircraft engine position number

An aircraft engine position number is like a label that tells us where an engine is located on a plane. It helps us know which engine we are talking about when we want to talk about it. Just like we have a name to identify ourselves, planes have engine position numbers to identify the different engines.

Imagine you have a toy plane that has two engines. One is on the left side and the other is on the right side of the plane. Now, if I say we need to fix the engine on the left side, you would know exactly which one I am talking about because you know which side it is on. This is what an engine position number does.

In bigger planes, there can be more than two engines and they can be located in different places on the plane. These engines can be numbered based on their location. For example, if there are four engines on the plane, the one closest to the nose of the plane might be called the number one engine, the one next to it might be the number two engine, then the number three engine and finally the one closest to the tail of the plane might be called the number four engine.

By using these position numbers, pilots, mechanics, and ground crew can easily communicate which engine they need to check or fix, making it easier to keep the plane in good working condition.