Well done on your A* at Maths!
Those results look good too...
Alright. Work exp for engineering might be difficult to obtain, that's no lie (I don't have any); but if you can prove your interest in the field and how the other ECs you do help boost your ability to cope with an engineering course/project, you'll be fine - you'll need to make sure your PS covers that. I'm hoping that your EPQ is on something related to Aero Eng, because that -would- be a very good talking point to cover in your PS (and your interview later on, if all goes well!)
External reading is also always a boon. And yes, do mention the Aerodrome stint; not just in a "work experience" mindset but what you loved about the experience (and how it's spurring you to want to do Aero Eng even more at Imperial, etc.)
So a recap of what to do for your PS:- Don't fret about the lack of work exp, it's hard to come by (although try if you can!) Look at what ECs you have, list them down in there, and say how they'll help you cope with the course. I'm a musician and performing artist and I've worked on loads of productions, as well as done homework help with junior schoolers - may not seem like EC activities "perfect" for engineering; but trust me, those things taught me more on how to delegate tasks in a team and have helped hone my interpersonal skills. I went from nooby stagehand to Audio Engineer in 5+ months at school, which I was pretty chuffed about because I started backstage tech from scratch - that kind of thing shows unis that you're a quick learner. But you'll have to "argue" it nicely in your PS.
- External reading around the subject is a good idea: you might find an area that you're quite intrigued about, and may want to bring it up in your PS as well. I did something slightly different: I talked about an experience I had with vaccinations and wanting to know more about medical technology after that experience. Look out for new key developments in the field you'll be studying. School doesn't teach me about stem cells made from bacterium and using Green Fluorescent Protein from jellyfish cells to diagnose cancer...it's stuff I found in the news. You might not have to know everything about how this new development works, but if you get asked about it in the interview ("so what new exciting things have you heard about?"), you'll be ready. And you'll even get to ask them how it works.
- That Aerodrome experience...don't veto a mention of it from your PS. I bet it'll also be a talking point at interview. You do want the admissions tutor to look at your PS and go "wow, what an engaging, talented person - I want to know more!"
Good luck with your app, and buzz me when you're in the final stages of your PS. If there's something I can help out with the best, that's probably it. :P