Air Day 3

When The Boeing Company acquired the Stearman company in 1939, it also acquired the design and production rights to the two-seat biplane that would go on to become the PT-13, PT-15, PT-18 and PT-27 series of trainers that would serve throughout the Second World War and beyond, becoming the prize in the collection of many an aviation aficionados to this day.

The "Kaydet" was initially received by the United States Navy in the form of the Model 73 production series model and designated as the NS-1 in no fewer than 61 total delivered examples. The Model 75 was derived from this production model and was then accepted by the United States Army with the more identifiable PT-13 designation, though these models were now fitted with a Lycoming-brand power-plant of some 215 hp. Further developments led to increasingly improved versions of the base Model 75 that featured a host of power-plant and instrumental changes. Kaydets were now being produced on orders of thousands and consisted of a slew of USN and US Army variants, differing mainly in engine types.

Introduction of the Continental-brand series of engines led to a new designation in the form of the PT-17. Later models produced with a Jacobs power-plant were further designated as PT-18's. The Boeing-Stearman design was also offered up in 300 examples to Canada as the PT-27 (featuring an enclosed cockpit), which in turn provided the further designation of "Kaydet" to their models. It is this designation which would go on to become the indicative designation to the series as a whole. The Kaydet name stuck and is still used today to identify all models derived from the original Stearman Model 75 - these include the PT-13, PT-15 and the PT-18 along with the Canadian PT-27.