The Berkut 360 is a tandem-seating, two-seat homebuilt canard aircraft with pusher configuration and retractable landing gear, built primarily of carbon fiber and fiberglass. The Berkut 360 is featured in the 2010 movie Kill Speed (Fast Glass). The prototype Berkut was designed and built by Dave H. Ronneberg as part of a business partnership between Ronneberg and Donald S. Murphy, called Experimental Aviation, that lasted from 1989 to 1992. In 1992 the partnership dissolved and Ronneberg, incorporating as Experimental Aviation, Inc., brought the aircraft to market as a kit, while Murphy wanted to shelve the project entirely. A subsequent series of lawsuits between the two resulted in bankruptcy for Ronneberg and Murphy as individuals and for Experimental Aviation as a corporation. The kit was resurrected in 1996 by Richard Riley and Renaissance Composites, with Ronneberg working as a consultant. The Berkut is derived from the Rutan Long-EZ, with the primary differences being retractable main landing gear, dual canopies, and molded fuselage, strakes, and wing spar. Like the Long EZ, the Berkut carries two people in a tandem seating arrangement. The front seat occupant has access to all instrumentation and controls. The rear seat, normally holding the passenger, is equipped with a side stick and throttle, but no rudder pedals, brakes, or instruments. Aerodynamic optimizations to the original Long-EZ airframe were made to increase performance and interior space. The fuselage was stretched and the nose, canard, instrument panel and pilot moved forward one foot (300 mm), to allow a heavier engine to be used in the rear. The main wing trailing edge was straightened, removing a small bend in the trailing edge of the Long EZ wing. The lower winglet was removed and the aileron size increased in both chord and span, significantly increasing roll rate. Early Berkuts used wings and canard that were structurally similar to the Long-EZ and used solid blue 2 lb/cu. ft. density Dow STYROFOAM PI cores cut to shape with a hot-wire foam cutter, but with carbon fiber reinforced polymer skins instead of fiberglass. The fuselage and winglets remained fiberglass. Later versions (kits produced after spring 1999) used fully molded carbon fiber canards and wings with high density, 5 lb/cu. ft. 1/4" thick PVC or SAN foam cores, leaving only minor fairings and tip surfaces to be carved from foam. The Berkut has always used the Roncz 1145MS canard airfoil, which is more tolerant of insect and rain contamination than the GU 25-5(11)8 airfoil originally used on the Long-EZ. The Berkut used a retractable main (rear) landing gear system designed by Shirl Dickey for his E-Racer homebuilt. Originally, Berkut used gear parts produced by Dickey, but over time they were repeatedly re-engineered and strengthened. Later kits had gear components produced entirely in-house. Like the earlier Vari-Eze and Long EZ, the Berkut kneels with its nose gear retracted to prevent the aircraft from tipping over backwards when parked without a pilot in the front seat. Some early Berkuts utilized hydraulic nose-gear extension systems, but most have used an electro-mechanical jack-screw. With the electric system, the pilot and passenger can climb into the cockpit, then extend the nose gear, raising the airplane with occupants inside. For more details of development, configuration, selected accidents and variants, click here.
