Okay kiddo, so you know how we need to put gas in our car to make it go? Well, planes also need fuel to fly! But different types of planes need different types of fuel.
So imagine there’s a ladder, and on the first rung are planes that use really light fuel called Jet A-1. These planes are usually smaller and don’t need to fly that far.
On the next rung up are planes that use a slightly heavier fuel called Jet A. These planes are a bit bigger and can fly further.
Then we have planes on the next rung up that use a fuel called Jet B. These planes are even bigger and can fly even further, sometimes all the way around the world!
So, basically, the higher up on the ladder a plane is, the bigger and more capable it is, and the heavier the fuel it needs to function. It’s like how when you grow bigger, you need more food to fuel your body.
Hope that helps! Any questions?