Eiri Avion PIK-20
The PAC -20 is a single-seat glider of the company Eiri Avion.
History
The PIK -20 was a development of students at the Technical University of Helsinki. Relevant designers were Markku Hiedanpaa, Hannu Korhonen and Pekka Tammi. The PIK -20 flaps used instead of Schempp- Hirth dive brakes to keep the speed according to building regulations in a nosedive when fully extended landing aids below VNE. The prototype was designed by the then rules for the standard class, the flaps - when present as the only landing aid and could be used only for landing - allowed.
A little later the rules of standard class were changed again, now only demanded that the flap does not move together with the ailerons or were superimposed. The " other " lift and or performance-enhancing properties of the flaps were not limited. This rule change, the PIK -20 was adapted and henceforth built as PIK -20B. Then were with the PIK -20B in 1975, both the British - American - and the Finnish National Championships won as well as the 1976 World Cup by Ingo Renner - 2nd and 3rd place also went to pilots on PIK -20B. As an option, the PIK20B was offered as one of the first gliders with carbon fiber spars, which lowered the weight of the wing considerably.
Following the success of the aircraft equipped with wing flaps IGC banned in the standard class all profile changing buoyancy aids and created the new 15 - m- class ( racing class ). For this class, the PIK - 20D was designed. Now you had 1:1 layered flaps and landing only on the top extension end Schempp-Hirth - flaps. The wing spar has now been made standard carbon fiber and also in some other places ( fuselage to accommodate the bending forces of the rudder, cockpit frame) were carbon fibers used for reinforcement.
Performance measurements showed that the PIK - 20D poorer performance has had as the PIK -20B. Therefore, some design changes were made. So with the nose pointed and the tailplane was moved a few inches forward. The real reason for the performance degradation but was in an enlarged section thickness, probably caused by warped shapes for the wings.
Jukka Tervamaki constructed a motor in a PIK -20B and so developed the prototype for later JT6 PIK -20E. For the PIK -20E were reinforced wing spars, a larger center section of the fuselage and needed a sweep back of the wings to 2 degrees due to the shift of focus to the rear.
A special feature of the PIK -20 was their method of preparation: All components are made from epoxy resins, which have a high thermal stability. The parts were annealed in an autoclave. It has also been completely dispensed with the usual gelcoat as a paint layer, the parts were instead painted in connection with acrylic paint. Due to the elevated temperatures during the heat, the PIK - 20s can be painted throughout in colors other than white, that is chrome yellow (RAL 1007), Blood Orange (RAL 2002), Gentian Blue ( 5010 ), Green (RAL 6018 ) or white aluminum ( 9006).
The PIK - 20D received on 7 May 1996 later in a " Design Change" aerobatic approval ( " Aerobatic Category" ) in the range of 6.6 g to 4.6 g Permitted aerobatic maneuvers are spin, turn, roll, loop, inverted flight, inverted flight curves, barrel rolls, and combinations thereof (eg, Immelmann, clover, Cuban Eight, etc.). Forbidden aerobatic maneuvers are uncontrolled figures ( torn / bumped rolls), figures in which the aircraft is flying backwards ( males, females ), figures with long-lasting negative impact ( Außenloop ) and inverted spin.