You may want to look into general engineering courses, or those that start off as "general" and allow you to specialise in some area later.
In the specific case of aerospace engineering, it's quite common for people to do a first degree in e.g. mechanical, electronic/electrical, materials engineering or something else, and then go on to work in the aerospace engineering sector. Sometimes they do a specialised MSc in Aerospace Engineering of some variety first, sometimes they go directly into the sector.
Bear in mind outside of London any job that pays £40k is more than enough to live on comfortably.