That's not very PC is it !

OK, Southall as well then ;)

did AI have the necessary permission to fly LGW-LHR (domestic leg) because I'm sure if a UK carrier had done similar in India, the DGAC would have insisted on it !

Happened to me once on a BA flight from Toronto to Heathrow. We ended up at Manchester due fog and there we sat for endless hours until the crew ran out of hours. We were then bussed to Manchester Piccadilly and sent home via train.