OTHER: Helicopter - Inside - Side-by-Side - Electrotor- MicroLite

Drawing: The gearing will be crown and pinion, quite similar to the lntermeshing and Interleaving configurations. See 1841

Bill of Material

• For a helicopter, a second counterrotating main rotor is more efficient than the main+tail rotor configuration.
• Franz Schoeffman's rigid rotor coaxial must be on of the simplest, cheapest and lightest of rotorcraft; gyrocopter and helicopter.
• If Franz's 2 rotors were moved to a side-by-side configuration the lift/power ratio will be noticeably improved,
• Flight Control:
• Tilting these 2 side-by-side rotors slightly towards each other should provide lateral stability.
• Weight-shifting is OK for flight speeds below transition, but not for faster speeds.
• Fixed-wing flight-controls are OK for speeds above transition, but not for slower speeds.
• A basic ruddervator on a reasonably long boom should handle pitch, yaw and roll; perhaps assisted by the weight-shifting.
• The ruddervator may eliminate the risk of the craft's forward velocity exceeding the ability of weight-shifting alone to recover.
• The ruddervator could be mechanically linked to the action of weight-shifting.
• The side-by-side will weigh slightly more than the coaxial but it will be producing more thrust than the coaxial. If the sizing of the side-by-side (prop, motor, power-train etc) was reduced to match the thrust of the coaxial, the weighs should be comperable.
• The individual rotors on the side-by-side should be more conducive to the inclusion of 2-stage pitch change, for autorotation.
• Yaw could be achieved by overlaying a portion of the boom with an variable position airfoil. Or by pulsing the 2-stage prop on one of the rotors while weight-shifting to under the rotor with the greatest lift. Could this cause one of the rotors to enter the vortex ring state?
• Franz's tripod legs appear to be a neat idea
• A concern might be the risk of one rotor only entering the Vortex Ring State.
• The booms swing back and the blades are aligned fore and aft alongside the tail boom for storage and transportation.
• Cable bracing is used where applicable to reduce the weight of the craft.
• IVO's electric variable pitch prop may provide Autorotative ability.
• Solenoid for each arm of Pilot(batteries) to provide for-aft and lateral weight-shifting.
• Motor and prop for scaled testing
• See information on AeroVantage ~ Transition Mechanism
• EVP UNIT FOR AXI 2208/xx EVP and AXI 2212/xx EVP GOLD LINE
• http://www.modelmotors.cz/download/Manual-EVP-eng.pdf

• Gross Weight: 550 lbs Or less if possible.
• Rotor Speed: 555 rpm.
• Blade: VR-7, 8'-8" radius, 5.25" chord.
• Collective Angle: 10.7º.
• Total Power: 20 horsepower ~ Momentum theory; 26 horsepower ~ Blade element theory. Why the large difference?
• Disk Loading: 1.16 lb / sq-ft.
• For comparative power requirements between configurations see; DESIGN: UniCopter ~ Electrotor ~ Rotor

• The tripod arraignment.

• Rotor supporting arms would swing forward and inward. Both 2-blade rotors would have their blades pointing forward and aft; or perhaps the blade grips might be modified so that all four blades point aft.
• The tail boom is detachable.
• Bowden cables between the mixer box and the rotor will simplify the swinging of the rotor spars.
• This gives a very collapsed configuration for storage and ground transportation.

• A UAV craft provides a safe way to develop and test the craft.
• Low vibration: For a camera mount this configuration should provide the least vibration. This is because there is no rotor to rotor interaction, the downwash is on a fuselage of thin tubing and there is no tail-rotor.
• Sophisticated remote controls, if required, could be developed by another company.
• Design:
• The spine and tailboom may be horizontal and slightly higher if the ELECTROTOR ~ SloMo or the 3-blade CVJ w/ Hub Spring were implemented at some later date.
• The battery packs will be separate items that will be attached at the rotors.
• The in-flight mission equipment will be a separate module(s) that will attach to the spline.

• Lateral Static stability: Point the two disks slightly inward.
• Consider using weight-shifting for flight control. See musings below.
• A ruddervator could be mechanically linked to the action of weight-shifting.
• Lateral Control: Lateral tipping of rotor heads. The head on the inside of the roll will tip inward where as the head on the outside of the roll will tip less or may not tip at all. To be controlled by the mixer-box. Note that this is also being considered for the Electrotor - Simplex and perhaps the MicroLite Interleaving. There should be a separate page for this subject and the calculations at some point in the future.

• Will lateral shifting of the pilot (batteries) be sufficient to enact a roll OR more importantly to recover from a lateral gust.
• Motor: A failure of torque to one rotor must be matched by an immediate matched by the removal of torque to the other rotor. .
• Control - Flight: The opposing torque of driving both rotors will increase the friction in the pitch and roll control bearings. This might result in high cyclical control forces.
• Vibration: The thrust (Collective) is by the rpm of the rotors. This means that the fuselage etc will have to be 'tuned' so that it does not have a frequency within the operational frequency of the rotors.
• Motor: Will the two motors be strong enough for any prolonged flying. They may require special cooling. Dry Ice :). What about spraying a fine mist into the motor and cool by evaporation????
• There is the possibility of an asymmetrical settling with power (vortex ring state) during an autorotation.

• The blades can be purchased.
• The thrust of the separate rotors will be better.
• The pitch adjustment exists with IVO blades.

• Propellers: See BUY: PropRotor - for MicroLite - IVO - Medium for information on Ivo props.
• Weight: See BUY: PropRotor - for MicroLite - IVO - Medium for information on Ivo props.
• Disk Area & Disk Loading: See BUY: PropRotor - for MicroLite - IVO - Medium for information on Ivo props.
• Blade Area; See BUY: PropRotor - for MicroLite - IVO - Medium for information on Ivo props.
• Go with the Medium:

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