I think there would be enourmous demand for a evening class/weekend classroom base course in the Central London area... there must be loads of people working in the city looking to get their ATPLs done but who struggle to get the time off work for a 2 week classroom stint followed by exams the week after (impossible for me).
I for one would pay a premium for being able to do classroom study on weekday evenings complemented with an occassional weekend.... unfortunately nobody has yet attempted to tap in to this potentially lucrative market.
I recon you could easily charge £10-15 a head for 2-3 hours of evening study on a weekday.... so with 10-15 students an instructor could make himself an easy c£150 for 2-3 hours work... not to be sniffed at!
Do the same for a Saturday or Sunday... say £40-50 for the day of say 7 hours classroom time and again with 10 -15 students you will be clearing c£500 for your troubles.
So any qualified ground school instructors associated with an approved school (London Met?) out there keen on making an extra £600 (gross) odd quid a week for one day at the weekend and one evening a week..... I'm sure we could get 10 people who work in the city that would be keen.
GSB