context: The PIK-5 was a single-seater glider designed by Kaarlo J. Temmes, a Finnish aerospace club. The PIK-5A Cumulus was developed on the basis of the Polish W.W.S.1 Salamandra glider, just like the PIK-5 had a solid wood structure. The aircraft type was designed to replace the older training machines commonly used by Finnish gliding clubs, such as Grunau Baby. PIK-5A's design began in 1945, and the first prototype flew its first flight the following year. Ilkka Lounamaa went on to develop the PIK-5A, and the upgraded version was named PIK-5B in 1949. A total of 16 aircraft were manufactured in B until the crash of the B-type OH-PAA in 1951 required the development of a new improved version. The PIK-5C model was awarded the design by Keijo Tiusanen. The C version came with a completely redesigned rudder and frame, and the original PIK-5A only retained the wing's aerodynamic design. The PIK-5 was the most common type of sailplane in Finland in the early 1960s, but the type gradually began to be replaced by newer German reinforced plastic machines in the late 1970s.
question: When did the PIK-5 fly its first flight?
answers.text: design began in 1945, and the first prototype flew its first flight the following year