1-EA by TsAGI, B.N.Yuriev/A.M.Cheremukhin

Original TsAGI 1-EA. 18k b/w photo from the "History of aircraft construction in the USSR" by V.B.Shavrov, Vol.2 p.414

B
asic experimental helicopter with 4-blade main rotor and four small 2-blade anti-rotation propellers (with variable pitch),installed in pairs at the ends of fuselage.
Fuselage was simple frame made of steel tubes,its construction was optimized during tests. Original rectangular structure with tension wires was replaced by more solid triangular without wires.
TsAGI 1-EA with modified fuselage. 13k b/w photo from the "History of aircraft construction in the USSR" Vol.2 by V.B.Shavrov, p.414
M-2 engines were selected because they did not require any special cooling in hovering regime. Because main rotor had solid blades, no special clutch was required and rotor started to spin once engines started (with compressed air).
On August 14, 1932 A.M.Cheremukhinreached altitude 605m. Unfortunately, The USSR at the time was not a member of an International Aviation Federation (plus secrecy, yes!), and this record could not be formally registered.
To conclude 1-EA story, it is necessary to mention that it was flown safely mostly due to well designed control system and pilot's skills of A.M.Cheremukhin. Simple straight link of main rotor to the power plant does not provide enough stability. Smallest variations in engine regime caused aircraft to move up or down, and required full attention of a pilot.
One built.
Modifications: 3-EA
Sources [6], Vol.2 p.414;
Technical data
Type 1-EA
Function experimental
Year 1930
Crew 1
Engines 2*120hp M-2
Length -
Rotor diameter 11.0m
Height -
Empty weight 982kg
Flight weight 1145kg
Ceiling 605m
Minimum Speed 0km/h
Maximum Speed 30km/h
3600 turn -
Takeoff roll 0m
Landing Roll 0m
Flight Duration -
Range -
Armament none
Modified March 24, 1997
by Alexandre Savine;		 Back to
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