US Bureau of Labor Statistics

"By law, airline pilots cannot fly more than 100 hours a month or more than 1,000 hours a year. Most airline pilots fly an average of 75 hours a month and work an additional 75 hours a month performing nonflying duties. Most pilots have a variable work schedule, working several days on, then several days off. Most spend a considerable amount of time away from home because the majority of flights involve overnight layovers. When pilots are away from home, the airlines provide hotel accommodations, transportation between the hotel and airport, and an allowance for meals and other expenses. Airlines operate flights at all hours of the day and night, so work schedules often are irregular. Flight assignments are based on seniority."

So they "fly" 900 hours a year. That should be at least close to your "in the air" question - give or take taxi, wait, etc. time.

For a few years, I was doing transcons each week, plus the occasional side trip, which adds up to about 500 hours a year.