Most of this is from my experience, but here it goes.
1. You love jet noise.
2. Whenever you hear a roaring/buzzing sound you immediately look up at the sky.
3. You can tell a 767-200 from a -300 at a quick glance.
4. Whenever you take a trip, usually you look forward to the flight more than the destination.
5. On pictures from the said trip a good majority was on the plane you flew.
6. You almost always take a window seat.
7. Aircraft type and airline is a high priority when picking a flight.
8. You can tell the difference between a 747-300 and a 747-400.
Feel free to add on.
I fit this