Karhumäki Tiira / Tern
Karhumäki activities began in 1924 at Keljo, near Jyvaskyla, and originally was of an amateur undertaking. Together with his brothers, Valto and Uuno, Niilo Karhumäki designed and built an aircraft and began to fly it. The first aircraft was given the name Karhu (Bear). The work was continued and the boys planned and constructed the Karhu 2, Karhu 3 and Tiira (Tern).
The Tiira was built in 1929. A reproduction of the 1929 Tiira tandem parasol monoplane began flying in 2004.