It’s always interesting to contemplate general aviation’s boom-and-bust cycles. While exceptions certainly abound, it seems every other decade since the 1930s has included introduction of new aircraft or new technologies that further advance the state of the art. The 1970s were an upswing, avocado-green vinyl upholstery and Continental’s Tiara engine notwithstanding. In addition to the iconic taper-wing Piper Cherokees, Cessna’s original Citation and Beech’s Model 200 Super King Air, the 70s also ushered in the Rockwell Commander 112/114 series of four-seat piston singles. …