When Piper PA-31 Navajo was created in the late ’60s, the original concept was to launch a new family of Pipers. The new model was a combi¬nation corporate/freight airplane intended to serve the heavy-haul twin market. The straight Piper Navajo was introduced in 1967, a founda¬tional model available in both 300-hp normally aspirated and 310-hp turbocharged versions. The Piper Chieftain came next in 1973, a stretched, heavy hauler that was to be¬come the top of the line with a pair of 350-hp engines. In 1975, Piper began offering an in-between model, the Piper Na¬vajo CR (counter-rotating), with mirror image engines in 325-hp trim.