WASHINGTON (AP) — Industry and government experts say pilots continually monitoring automated cockpit systems pilots may see but not register signs of trouble.

That's a problem that is showing up repeatedly in accidents and may have been a factor in the recent crash landing of a South Korean airliner in San Francisco.

Experts say teaching pilots how to effectively monitor instruments has become as important as teaching them basic "stick-and-rudder" flying skills. The comments came at an annual safety conference of the Air Line Pilots Association, the world's largest pilots union.

The experts say the sheer volume of monitoring required even on the most routine flights and the diversity of systems that must be monitored has increased.