Depends which variety of engineering you want to do.
There are loads of threads here and elsewhere on the subject, but it boils down to whether you enjoy getting your hands dirty or not.
If you do, then look at technician/maintenance type courses, some of which are part time allowing you to avoid a period without any income.
If you don't, then I'd suggest building upon your BEng and doing an aero-eng MSc, likely to be full time for a year - that'll get your theory back up to scratch, and open up all sorts of opportunities in aircraft design / analysis / research.
Incidentally, don't just think in terms of the airlines. A lot of the most interesting engineering isn't done in the airlines - you could be working for BAE designing and/or building Eurofighters, Westlands on helicopters, Boeing on the next generation airliner, or places like ARA doing aerodynamic work on virtually anything.
G