The sheer volume of flights in the skies over Southeast Asia is putting pressure on outdated air traffic control and on pilots to take risky unilateral action in crises such as that possibly faced by AirAsia Flight QZ8501.

Pilots who have flown the route from Indonesia to Singapore say that it is not unusual to experience delays in getting approval for requests to increase altitude to avoid bad weather, and that some requests are eventually rejected due to the number of other planes in the area.

That leaves pilots flying in a region of volatile weather conditions facing a high-risk challenge: deciding whether to take matters into their own hands and declare an emergency, allowing them to take action without getting permission from air traffic control.