These are spare plans for the DHC-2 Beaver from AIRSAIL.
About the real aircraft:
The de Havilland Canada DHC-2 Beaver is a single-engined high-wing propeller-driven short takeoff and landing (STOL) aircraft developed and manufactured by de Havilland Canada. It has been primarily operated as a bush plane and has been used for a wide variety of utility roles, such as cargo and passenger hauling, aerial application (crop dusting and aerial topdressing), and civil aviation duties.