Crowded skies in Southeast Asia put pressure on pilots, air traffic control
Weighing risks in volatile weather becomes more difficult, pilots say, in a region that has seen explosive growth in its budget carriers
The sheer volume of flights in the skies over Southeast Asia is putting pressure on outdated air traffic control and on pilots to take risky unilateral action in crises such as that possibly faced by the AirAsia Flight QZ8501.
Pilots who have flown the Indonesia to Singapore route say it's not unusual for delays to requests to increase altitude to avoid bad weather - and for requests to eventually be 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: when to take matters into their own hands and declare an emergency, allowing them to take action without getting permission from air traffic control.
Most consider that step, which requires them to broadcast a wideband call to other aircraft in the area and that will later be closely scrutinised by regulators, a last resort.
"As a professional pilot, you are obligated to think quickly," a pilot for Quantas Airways who has 25 years experience in the region said.
"If you've signed for the plane, as we put it, you've signed for potentially 300 passengers and millions of dollars worth of aircraft; that's a multibillion dollar liability. Part of the job is to balance the risk and make a snap decision," he said.