well, O'Hare is a WHOLE LOT bigger than the airport i work at. the biggest thing we get is a Citation V, which is a petty ant compared to Boeing 737's, 777's, 747's, and such. to put it in more perspective, my work has 1 runway at 4000ft long, O'Hare has 6 runways with three of them being over 10,000ft long.