It's nice to know I'm not the only one who obsesses about watching airplanes. Before I graduated high school I used an old refractor telescope to follow contrails and see what sort of airplane was making them. More recently, I bought a used radio scanner to listen to air traffic control, and once sat under Regan's approach vectors and used the radio to know what was inbound next. The road that leads to Udvar Hazy has a section that is directly beneath the approach to one of the main runways at Dulles, and for awhile parking and letting the planes fly over was a good way to distract Olivia. Fun stuff!