How do pilots find their way in the empty sky?
Dear colleagues, this is my first post after my long silence. I hope that some will find this useful and beneficial.
Unlike the older generation of aircrafts, modern airplanes are capable of flying longer distances and can remain in the air for longer periods. As the popularity of point-to-point flights between cities increase, flights lasting between 14 to 18 hours are becoming the norm nowadays.
Have you ever wondered how do pilots navigate and find their way to the destination over such long periods of flying? Flights of such duration will pass through many time zones and will fly throughout the night. While the passengers are sleeping, how do the pilots see where they are going? How can the flight arrive at the destination and be able to land on runways only 150 feet wide, touching down precisely at the right spot?
When I first started my flying training, I was using the topographical maps for navigation. Finding my way around was by relying on visual cues. I had to fly low to remain below clouds to maintain visual contact with the ground. Landmarks such as roads, rivers, buildings and any other prominent features were used to determine my position. The navigation instruments fitted in those aircrafts were very basic and lacked sophistication, thus the reliance on ground features to find my way around during flight.
Nowadays we fly above clouds at altitudes above 30,000 feet for long periods. Instead of the topographical maps we use the “airways” map to help us navigate, to determine our position and to know where we are going.
The difference between the old generation of aircrafts and the new generation of aircrafts is in the equipment fitted that are used for navigation. These new equipment changes the way pilots navigate. We do not have to rely on ground features anymore. How could we when we have to fly throughout the night and over oceans for long periods of time.
With the modern aircrafts the route of the flight is programmed into the onboard computers before the flight, from takeoff right up to landing at destination. Apart from the routing, the pilots will also program other information such as the weight of the aircraft, the thrust required for takeoff, the initial cruise altitude as well as the forecast enroute wind for the selecting route.
Flight Management Computer where the route of flight is programmed
Once airborne the autopilot will be engaged and it will follow the route as programmed. The pilots will have to continuously monitor the accuracy of the route flown by the aircraft against the airways charts. Should there be a requirement for the aircraft to be re-routed for whatever reasons, the pilots will refer to the airways chart and reprogram the new route into the onboard computer. This process will be repeated until arrival at destination.
Sample of airways chart used for North Atlantic crossing
Written by Azharuddin Osman