KHan - as you have a degree in aerospace already you should be aware that it may well work against you if you apply to the RAF for anything other than commissioned status. The logic being that if you were non-commissioned but held a degree then you could well be more qualified than your commissioned superiors - technically. This particularly applies if you're CO rose through the ranks to commissioned status - serving officers don't necessarily have degrees. New entrant officers may well be expected to have a degree.
A tip - the RAF don't like to be referred to as the RAF if you find yourself in front of a selection board. Always refer to 'The Royal Air Force'. They also expect officer candidates to exhibit 'dash'. It's a throwback to their historic origin as a side show - The Royal Flying Corps (1914-18) - when the officers were transferee cavalry officers that wanted to train as aviators. To have 'dash' you would be considered to be erudite, well mannered and spoken, with an air of decisiveness, leadership etc. For new entrant officer selection your written english has to be pretty good - spelling, grammar etc.
If you want to see a contemporary example of someone with 'dash', check out Brendan O'Brien who hosts some show called 'Flightline' or something on Sky.
A degree in aerospace may well open some other doors. Dunno who advised you that an engineering degree would preclude you from airforce pilot training but that sounds like BS to me. Check out the pilot training thread a week or so back if you can find it, for some general tips on flight training. Upper age limit for airforce pilot-training - 23 1/2 on entry last time I checked. If you fancy a really freaky option try applying to the USAF/USN/USAAC/USM as a flight crew trainee/serviceman. For aerospace career opps check out NASA, possibly, or Boeing, Macdonnell Douglas, Bell Textron, Bombardier, De Havilland Canada, CAA, RCAF/Canadian Civil Aviation Authority, Airbus Industries, British Aerospace Military Aviation Division (Preston) etc..
In short, the sky's yer lobster...