Can someone explain how per diem works in the airlines? Tell me if I'm incorrect here, but from what I can tell, if your gone on a 2 day trip, let's say, and your gone 34 hours, does this mean you get (Perdiem rate * 34) or what? Typically how much does one make off of perdiem during a 1 month period? (for someone on a line, and 1 on reserve) Is this taxed?