21.   Again and again this summer, their vacation plans have been encountering the gridlock staggering the air traffic system.

22.   Airline executives have been complaining that the long-outmoded and mismanaged air traffic control system is seizing up under the strain of greater traffic.

23.   Airline service woes are sparking new criticism in Congress, while the industry blames lack of government investment in air traffic systems.

24.   Airlines blame the air traffic control system.

25.   Airlines blame the FAA because of an antiquated air traffic control system.

26.   But Crandall argued that a Southwest flight puts just as much strain on the air traffic control system as an American Airlines flight.

27.   But experts say it places tremendous stress on airport operations, security and the air traffic control system by crowding planes into the sky at peak hours.

28.   But money is only one reason the air traffic control system is antiquated.

29.   But like the military contracting business, air traffic control systems are expensive to develop and appeal to only a small number of customers.

30.   But the airlines plan to shift the debate to the question of expanding the capacity of airports and the air traffic system.