If you want some insight into why the department of justice put a gate hold on the merger between American Airlines and US Airways, here's a number to ponder: 13 million seats--gone. That's how many airplane seats have disappeared over the past year--removed from the system by airlines as they reduce capacity. According to the website Aviation DataMiner, these cuts have come from across the industry. Only ultra-low-cost carriers Spirit and Allegiant are growing. This means life in the skies will not be improving anytime soon: no empty seats, no room overhead and stressed-out staffs. With fewer seats available, the domestic load factor--the percentage of seats filled--reached a record of 87.1% in June. And as there is little or no capacity growth in the forecast, the future of flying promises more cramp for more cash.