These were your grandfathers airplanes. After World War II, Piper, Aeronca, Taylorcraft, Luscombe and ERCO (Engineering and Research Corp., maker of the Ercoupe)-cranked out thousands of easy-to-fly two-seaters to meet temporary post-war demand. Today, you can buy one of these LSA-qualified antique airplanes for around $25,000. Spend more, get more; less and look for rust, worn engines and old fabric. Many old airplanes qualify for LSA provided theyre two-seaters or smaller with a max gross weight of 1320 pounds. Well review five popular models: Pipers J-3, the Anthony Russo