When travelling by air, a traveller may estimate the different times of Salaat through the window seat. The commencing time of Fajr, Maghrib and Esha Salaats can be easily estimated through the break of dawn and night setting in respectively.
If one experiences difficulties in estimating the times for Dhuhr and Asr Salaats, he should seek the assistance of a flight attendant. Enquire about the place the plane is flying over and the time. In my experiences of travel, the flight attendant with the assistance of the cabin crew readily provide the information. Also, enquire from them the direction of Saudi Arabia in relation to the place you are flying over. The direction of Saudi Arabia can also be calculated from the map and movement of the plane which is generally projected on all international flights.
and Allah Ta’ala Knows Best
Mufti Ebrahim Desai