• Engine and differential.

• Limbach L 275 E is 21.2 hp at 7,000 rpm. Designing at 17.6 hp at 5,800 rpm. Spec page
• Motor is air-cooled opposed two cylinder, 2-stroke type.
• Displacement 274 cm3 ~ 16.72 cub. inches
• No starter. No generator. There is probably no reason for either. The engine can be started by a portable starter, as used with some racing cars, since it's weight is detrimental and there will never be a need to restart it in flight; unless it is remotely landed.
• Power Required to hover:
• Intermeshing; Momentum = 8.6 hp, BEMT = 9.2 hp.
• Interleaving; Momentum = 7.3 hp, BEMT = 10.5 hp. Why is the BEMT higher than that of the Intermeshing?

• Cooling:
• A round opening of approximately 5 or 6" diameter could be located at the aft of the fuselage just below the tail boom. This openinf would be centered on the centerline of the engine's crankshaft. A shaft would go from the back shaft of the engine to a fan that is located in the opening. The engine will not be running at full power during hover, therefore the fan should provide sufficient cooling. During high-powered forward flight the additional airflow will provide additional cooling.

• Future alternative to Engine.
• It looks like the new Plettenberg - Predator 37 will be ideal for a single motor drive. 20.1 hp and 4.2 lbs
• Alternatively, consider the Plettenberg - Predator 30. 14.75 hp and 3 lbs.
• Both of the above have roughtly 4.8 hp/lb. Therefore the use of two motors ( 1 for rotors and 1 for propeller), may be more efficient in terms of control and total powertrain weight.
• Some information on motors; DESIGN: ~ Single-Bladed All Electric Rotor - Motor

• Google search for "Hollow Shaft Motor": (13,100 hits)
• Xx

• Plane flew vertical with the Predator 30. It weighed 15 Kg (33 lbs)
• Prop delivers 5 lb /hp. Flettner delivered 16 lb lift / hp. This craft is interleaving which should be slightly greater than the interleaving.
• 33 * 16/5 = 106 lbs. Is this enough for a vertical take off? If not, use the 37 for the rotors and the 30 for the propeller.
• The Predator 30 produces 11 kW. The 38 delivers 15 kW.
• The 37 should, theoretically, be able to lift 144 lbs on its rotors. Note that this provides little, if any, power for climb and particularly the prop.

• Ultralight Electraflyer web site.
• Electraflyer video.
• More information on the trike.

Trike with motor, controller and gauges installed	85 lbs (39 kg)
Largest battery pack (5.6kwh)	78 lbs (35 kg)
Total of above (excluding pilot)	163 lbs (74 kg)
A true legal part 103 ultralight even with largest pack.	247 lbs (112 kg)
G.W. of UniCopter - UAV, ~ 1/2-scale	164 lbs (75 kg)

Same Page ~ Different Craft: ~ SynchroLite ~ UniCopter

Introduction Page | SynchroLite Home Page | Electrotor Home Page | UniCopter Home Page | Nemesis Home Page | AeroVantage Home Page