Valmet PIK-23 Towmaster
PIK Pik-23 Suhinu
 
 Pik-23-01
 
The Valmet PIK-23 Towmaster is a Finnish two-seat 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 Suhinu (Suhinu is a contraction of Super Hino = Super Tow-plane). Later on, the Helsinki University of Technology and Valmet Oy joined the project and the design process started from scratch. The goal was to develop a target/glider tower, which also could be used for basic training. It was given the name "PIK-23 Towmaster".
 
 Pik-23-02
 
Only two aircraft were manufactured, one at Valmet and one at the Helsinki University of Technology. The first aircraft, OH-TOW, made its maiden flight on March 22, 1982, flown by Mikko Järvi. The second aircraft, OH-TUG, flew the following year. OH-TUG was written of in 1991.
 
Valmet marketed the aircraft intensively, but no orders followed. It was also investigated if the aircraft could be sold in parts, for self-assembly, in order to lower the price. In its intended role as a glider tower, the PIK-23 has been quite successful.
 
PIK-23
Engine: 1 × Avco Lycoming O-360-A4M, 130 kW (180 hp)
Propeller: 2-bladed Hoffmann fixed pitch
Wingspan: 10.00 m (32 ft 10 in)
Wing area: 14.00 m2 (150.7 sq ft)
Aspect ratio: 7.14:1
Airfoil: NACA 632415 (modified)
Length: 7.19 m (23 ft 7 in)
Height: 2.90 m (9 ft 6 in)
Empty weight: 590 kg (1,301 lb)
Max takeoff weight: 870 kg (1,918 lb)
Fuel capacity: 200 L (44 imp gal; 53 US gal)
Maximum speed: 250 km/h (160 mph, 130 kn) at sea level
Cruise speed: 220 km/h (140 mph, 120 kn) at 3,660 m (12,010 ft) (65% power)
Stall speed: 78 km/h (48 mph, 42 kn) (flaps down)
Never exceed speed: 281 km/h (175 mph, 152 kn)
Range: 1,250 km (780 mi, 670 nmi) at 3,660 m (12,010 ft) (65% power)
Endurance: 6 hr 30 min (55% power)
Rate of climb: 5.80 m/s (1,142 ft/min)
Takeoff run to 15 m (50 ft): 320 m (1,050 ft)
Crew: 2
 
 Pik-23-03