Three US Airways jets came uncomfortably close to crashing into each other above Ronald Reagan Washing National Airport a month ago, thanks to botched instructions from the air traffic controllers there.

This followed an incident in March that has become depressingly familiar: A controller fell asleep on the job, forcing two planes to land without assistance from the tower. The Federal Aviation Administration reported 1,887 such “operational errors” in fiscal 2010, up from 1,234 the previous fiscal year.