It seems to me that you need some professional advice on domicile, residence and place of earnings' generation.
I would suggest that you get hold of a copy of BALPA's magazine, 'The Log'. There are usually some aviation experienced accountants advertising within those pages.
Alternatively you could access The Telegraph newspaper on the net. They have quite a reasonable section for expatriates under the money/tax section; although it does not appear that you fall into that category.
What I would not do, under any circumstances, is to ring the Inland Revenue with your queries. They are usually so terribly helpful as they nail you to the cross.
