If you contact Wilfred C. Fry in Worthing, Sussex you should get a proper answer, it may cost you a few quid though!
Sounds as though you may be liable on that part of your income that you earn in the UK, if you remain in UK airspace etc. etc. It is my understanding that provided you remain outside the UK for more than 183 days per year you should be OK on the overseas earnings BUT do you keep a residence for your use in the UK? and so on, really you should ask tax professionals. Best of luck.