A light aircraft flew overhead. Its tiny engine puttered energetically, like fingernails tapping a snare drum. The aircraft seemed appallingly flimsy. With its eerie, computer-designed lifting surfaces, it resembled a child’s paper toy: something made with pinking shears, popsicle sticks, and tape. The wing edges trailed off into feathery ribbons and long tattered kite tails. It seemed to be staying aloft through sheer force of will.