..so g/a at LGW with 1400kg and burn 1000 on the way - don't tell the residents around LHR what is coming over their heads shortly!
Hi BOAC thats the whole point of commiting, LHR is no longer an option. Now you ARE going into your final reserve for a circuit at LGW and a MAYDAY is mandatory.
Not a good position to be in but allowed by FCO's.
Edited to add that some airlines do not carry 5% contingency, but a statistical contingency (normally enough fuel so that div + final reserve fuel will not be eaten into on 99% of the flights on that route) which may well be more than 5% for JFK to LHR. So to say 5% is 5% is are not (always) strictly correct.