Nervous for my RAF aptitude

What you have to realise is the AST isn't so much of an intelligence test. Sure, you need to know the basics, but I guarantee that anyone could answer all of the questions correctly if there wasn't a time limit. It's more a test of how well you work under pressure. When you have a lot of tasks to complete in a short space of time, how do you deal with it? Do you get your head down and power through it or do you panic, and start making mistakes? This is a situation you'll face in training often, and one that the test is trying to prepare you for, as well as working out if you are knowledgable enough to have the capacity to be trained to the required standard for your trade.

Of course you're nervous, you wouldn't be normal if you weren't. It's how you deal with those nerves that will make the difference.

The test is structured so that you need to average out your scores to make sure your group score stays high. 80% in every section but a 20% in spatial may drag your group score down enough to be a fail.

For the electrical and mechanical, you should revise how circuits work (parallel and series), basic ohms law, levers, gears, pulleys, tools and mechanical advantage. An understanding of these topics should get you through it nicely.

For the spatial, find a small object in your house and just put it down and have a good look at it, visualise what it would look like if it was rotated. Even better, put a small bit of blue tac or somethng on one of the edges or corners, and get family and friends to move the shape and move the blue tac every now and then. You'll soon pick it up and be able to spot when it's still in its original position and when it's been moved.

Be confident, be determined to succeed, and you'll be giving yourself the best chance.