How to calculate travelling time Duration from one country to another country

[whitestonek]

I have one table with Columns like FROM DATE, TO DATE WITH TIME duration, COUNTRIES, STOCKS FIELDS.So, Flight moved from India to China on the particular date. Here I want to calculate travel duration with GMT. How to implement this in set analysis.Please suggest ASAP.

[wade12]

convert local departure time to GMT,

convert local arrival time to GMT,

duration = arrival GMT - departure GMT.

best wishes.