ATE-3 Autogyro

Fiberglass rotor blades 1965.

I graduated from the Helsinki University of Technology in 1963 and went to work at the Finnish Air Force Headquarters as a maintenance engineer for helicopters. And I was a pilot as well, flying Finnish Air Force primary trainers. It was at this time that I met Aulis Eerola, a very skilled helicopter mechanic at the Utti Helicopter Base. Together we started to develop the autogyros further. The first thing we did were all fiberglass rotor blades, an unknown field even in the helicopter industry at the time. The first design was a blade set with an NACA-0012 section but later we switched to an NACA 8-H-12 section. Two sets of blade molds were built. The new blades were first test flown in a modified JT-1 fuselage (JT-2).


Aurogyro ATE-3 1968, OH-XYV.

With the rotor blade development successfully underway I set to design the next machine, the ATE-3 (Autogiro-Tervamäki-Eerola). The airframe was of welded steel tubing but rotor blades, propeller, cockpit and tail surfaces were all of glass-reinforced plastics. The cockpit was "stolen" from the Finnish UTU fiberglass sailplane under development at the same time. The rotor diameter was first 6.5 m but was later increased to 7 m. The power plant was a modified VW-1700 racing car engine.
Like so many other prototype aircraft the ATE-3 at first had a number of dangerous defects which caused some hair-raising situations and crashes: blade flutter, power loss due to too lean mixture, carburetor icing, etc. But finally all of them were ironed out and the thing started to fly well. The machine had a role in the Finnish film "Leikkikalugansteri" (Toy Gangster) by Spede Pasanen and Ere Kokkonen.
Three different tail types were tested in the ATE-3. The third and final one was a V-tail which offered the best longitudinal stability (to prevent PIO, or Pilot Induced Oscillation) but the lateral stability was not as good as with the other types. After flying the machine for three years, we sold it to a flying club in Kokkola town and started again a new project.

The ATE-3 was described in detail in SPORT AVIATION magazine, in both the Feb.1969 and May 1971 issues and in POPULAR ROTORCRAFT FLYING 1969.

ATE systems

ATE in the Air

Eerola in the controls

 Three more ATE-3 autogyros have been built: from the left Siitonen and Paavilainen , Arvo and Hannu Taupila from Finland and an ATE-3 gyro from Denmark.

The other Gyros