Flying Torquewrench
It depends.....simply spending lots of time outside the UK on trips/tours but having partner/dog/house/kids in UK will not reduce taxation, as a recent Court Case has shown.
If, however, you can show the IR that you spend less than 90 days per annum in the UK and that your "centre of interest" is outside the UK then you may be able to pay reduced taxation in the UK............you may well however be clobbered by the tax authorities in the country of your residence.
If done properly it's all above board and legit, The regulations are all available from the Inland Revenue's website, or ring them up - despite what others have said I've always found them OK and they will even send you nice booklets explaining the whole process.
Finally I would if you go via BALPA and their preferred accountants be warned - if you decide to engage them you will find them very expensive