Valmet PIK-23 Towmaster or Suhinu is a Finnish twin-seated glider towing/primary trainer aircraft built entirely out of composite materials in the early 1980s.The Finnish technology students aviation club suggested in the 1970s, that a new aircraft should be developed for glider towing. The work focused on the improvement of a previous design, the PIK-19 Muhinu. Later on, the Helsinki University of Technology and Valmet Oy joined the project and the design process started from scratch.