21.   At times, the hike seemed less like a trek than llama traffic control.

22.   According to the transcript from air traffic control, there were two short radio bursts, probably around the time the plane was taken over.

23.   All I had to do was spend a half-hour once a week handling morning traffic control in the school parking lot.

24.   Air traffic control picked up a transmission from the San Francisco-bound flight as it neared Cleveland.

25.   Air traffic control?

26.   All of this makes air traffic control more complicated during busy times and contributes to delays, he added.

27.   Breakdowns may be likely in power grids, telephones, customs services, air traffic control, ports and the oil industry.

28.   But it is proving controversial with some aviation groups because it would impose new user fees to fund air traffic control.

29.   But millions of Mexicans drivers know that hardly anyone pays attention to legal traffic controls.

30.   But there is a difference in air traffic control.