Most people know that seniority is the way of life at the airlines. But seniority is a fickle thing. It matters in all aspects of your day-to-day lives, and some pilots will study the minutiae of seniority until they can’t see straight.

When I was at Comair, there was a captain who was famous for having been the most junior captain in the company for a number of years. He was on reserve, and he had the worst possible schedule one could get. He never had weekends off; he got the vacation nobody wanted; he had the worst trips. But, as he always pointed out, he was a captain. The guy who was one number—one lousy number—below him was the most senior first officer. The FO had the best schedule, his first choice in vacation, and a lot of days off, but he was still an FO making significantly less money. He also was not logging turbine PIC time, which was making his future job searches much more difficult.

In every airline, in every category, there is that one person who is just one number away from being where he or she wants to be. This person’s reasons and desires aren’t always known, but in time those desires can be fleshed out. It becomes most obvious when the company opens a new bid for something, and you see pilots trying to jump in to get what they want. With all of the advancement taking place now, it’s almost a linear progression for a lot of pilots who have waited years for what they want. But there are also strategic bidders.

For most airlines, being on reserve is the least desirable option, and in some cases, it’s downright brutal. Many first officers will try to wait until they know they will be assured of being off reserve before moving over. This is risky on a couple of fronts.

First, unless you know what other, more senior FOs are thinking, you may find yourself getting left behind for the left seat more than you might have imagined.

Second, even though this is a boom time, you run the risk that movement will stop for unforeseen reasons for an indeterminate amount of time. The captain I mentioned above made his move for exactly this reason. Had he waited, he would have been stuck in the right seat at much less pay for a number of years.

Another common unknown is an impending change to the union contract. If new work rules or better pay rates are on the horizon, a strong argument can be made for making the move to the left seat sooner versus later, especially if you will be a relatively junior captain.

Studying the minutiae of seniority can also tell you just when you can expect to hold weekends off, holidays, morning versus evening trips. Vacations are tougher to figure out because not everyone wants or needs a summer vacation or the week at Christmas, but you can still see which way the trend is going for your seniority. And, as is so often the case, there is almost always a stark dividing line between two pilots who are just one number apart.—Chip Wright