Design development and flight testing of PZL-106 Raven aircraft

The article is a discussion of the development of the design of the PZL-106 Kruk agricultural airplane, with particular emphasis on individual prototypes and development versions, as well as ground tests and flight tests. The organization of such tests conducted by the aircraft manufacturer PZL WSK-Okęcie under the supervision of the Civil Aircraft Control Inspectorate is presented, which resulted in a significant improvement of the aircraft development process. Problems that arose during the modernization of the aircraft's design, including those that arose during flight tests, are described, as well as ways to overcome them. Also included are archival, previously unpublished photographs depicting the use of the aircraft in various parts of the world.