Russian Aviation Museum

One of the first ultra-light projects of the SKB KnAPI (СКБ КнАПИ), started in 1968. Group lead by designers A.I.Nikitin, V.P.Kotliarov and V.V.Frolov included number of KnAPI students, who participated in design and construction of the aircraft.
Group studied variety of ultra-light hydroplane schemes, and selected very unconventional one, resembling R.L.Bartini VVA-14 and KOR.SVVP-70. ELA-7 was built around large rectangular center wing section, enclosed between catamaran-style floats. Trailing
edge of the center section was extended by small outer wing sections, carrying ailerons. Leading edge of the center section carried a pilot-controlled flap, used to re-direct part of the propeller flux and oncoming air flow under the wing (dynamic
augmentation of the air cushion). Trailing edge also carried a flap used to regulate air flow.

Engine was installed on the leading edge, ahead of the wing. Cockpit was located in the extension of the engine nacelle. Twin tailboom carried V-shaped tail.

Aircraft was built of wood, with almost 100% plywood skinning.

Trials were carried out during Summer 1971, on the Mylki lake not far from Komsomolsk-on-Amur. Insufficient power and low efficiency of propeller did not allow ELA-7 to accelerate above 36km/h. Most of trials were concentrated on the air cushion effect.
Additional lift of 100kg created by combined wing-in-ground and air cushion effects was observed.

This was considered a success by the team, and they started another project with improved airdynamics.


Type ELA-7 (ЭЛА-7)
Function Experimental hydroplane
Year 1971
Crew 1
Engine
Type MT-8
Power 32hp
Wing area 14m2
Weight
Loaded 430kg
Wing Load (kg/m2) 30.7
Power load (kg/hp) 13.4
Speed
taxi 36km/h