11.  The IRS has been in litigation with the former United pilots around the country, with differing results, depending on the federal appellate circuits where the pilots live.

12.  The lucrative contract signed by United pilots has rippled across the industry.

13.  The United pilots are demanding raises that would make them the highest-paid pilots in the industry.

14.  They also made the biggest financial sacrifices, says Ken Bradley, a United pilot and spokesman for the Air Line Pilots Association.

15.  They fear the pending takeover of US Airways will lead to US Airways pilots getting plum jobs that United pilots would otherwise receive.

16.  United Airlines pilots came and went.

17.  United pilots, Becker said, saw that as a threat to continued advancement.

18.  United Airlines pilot axes passenger who tries to force his way into locked cockpit.

19.  United pilots successfully eliminated a lower pay scale at the United Shuttle, a move Delta pilots want to mimic.

20.  A standoff with United pilots led to a summer of thousands of flight cancellations and delays.