Think “twin trainer” these days and probably the first airplane that comes to mind is the Piper Seminole, the sole survivor from the mid-1970s battle among Beech, Grumman and Piper for the twin-engine training and single-engine-owner transition market.

Unlike the Beech Duchess and the Grumman Cougar, which ended their runs not long after the light airplane market went south beginning around 1980, the Seminole has risen from Piper’s pools of red ink not once but twice. A new copy today runs about $485,000. Buyers all go for the Avidyne option, which pushes the price to $533,200. …