As a matter of interest and a fact which some may not know who have families (I didn't until two weeks ago!) and who are considering the career instructor route there is the 'Working Family Tax Credit'. I called them a couple of weeks ago and offered them the scenario that I could potentally end up earning £12,000 pa as a flying instructor. (Is £12,000 optimistic?) Now taking into account means testing, personal circumstances etc. they advised me that with two children, mortgage etc that they would make my wage up to take home £259 per week. Now knock of what you spend on flying per week and suddenly things look a tad better?
Problem in when the kids reach 16! Oh well.....