Why do some airplane headphones have 2 Jacks instead of 1 everywhere else?

Question

Every time I go on a plane it is about a 50/50 chance between headphones with 1 jack or 2.

Why do some have 2 jacks? What is the function of it?

In: 21

Answer 1

Some airplane headphones have two jacks because they are designed to be used with in-flight entertainment systems. These systems often have two audio channels, so the headphones need two jacks in order to hear both channels.