(1) Flight hours
Flight hours refer to the transportation time from the departure airport to the destination airport, including transfer time. The departure and arrival times on the flight schedule are based on local time. The time difference must be calculated to calculate the flight hours.
(2) Time difference
The difference in local time between regions of different longitudes caused by the rotation of the earth is called time difference. When an airplane crosses a longitude, there is a discrepancy in time. Calculating time difference is very important for arranging flights and better air transportation. In 1884, when the International Meridian Conference was held in Washington, in order to overcome the time differences between countries (regions), it was stipulated that the original site of the Greenwich Observatory in London, England, was the starting point of the 0° meridian (also known as the prime meridian). The 0° meridian to the east and west of 7.5° each constituted the zero time zone, also known as the central time zone. The time zone of the central time zone was called the Greenwich Mean Time (GMT). The 180° meridian was used as the central meridian to demarcate 12 time zones in the east and west, dividing the world into 24 time zones. Each time zone spans 15 degrees of longitude and the time is exactly 1 hour.
(3) Flight time conversion
The flight time and the time difference between two places can be converted into the world standard time by comparing with the Greenwich Mean Time as the standard. In the flight schedule, the time of each city is the local standard time. OAG, a global flight data provider, has published an international time calculator, which lists the time difference between the local standard time and the world standard time of each country (region). You can scan the QR code for details.
(4) Flight time calculation
A passenger takes a China Eastern Airlines flight from Beijing Capital Airport (PEK) to Los Angeles Airport (LAX). The departure time is 10:30 Beijing time on July 8, and the arrival time in Los Angeles is 16:50 local time on July 8. Calculate the passenger’s flight time.
The calculation steps are as follows.
① Find the standard time of the departure and destination stations from the international time conversion table.
PEK=GMT+8 (local standard time)
LAX=GMT-5 (local standard time)
② Convert the local time of departure and arrival into Coordinated Universal Time (GMT).
PEK10:30=GMT1+8(local standard time)
LAX16:50=GMT2-5(local standard time)
Then
GMT1=10:30-8:00=2:30
GMT2=16:50+5:00=21:50
③Subtract the departure time from the arrival time to get the flight time.
GMT2-GMT1=21:50-2:30=19 hours and 20 minutes