0829

Item 0829

Gyro/Heli V

Unified Gyrocopter / Synchropter (future Compound?)

Operational Profile:

Start engine. The propeller will then be turning at around 1000 rpm and the rotors may be slowly turning.

Taxi to position for take of, using rudder (foot pedals) for directional control and propeller for thrust.

Apply the wheel brakes.

For Takeoff: Increase engine speed to its maximum rpm. Initially; the rotor collective pitch will remain at the low autorotation value, the speed of the rotors will come up to 100% RRPM (operational speed) and the propeller will come up to around 70% PRPM. Next; as the engine's speed and power continue to increases, the rotors' speeds will remain at 100 RRPM, the rotors' pitches will start increasing and the propeller speed will continue increasing. When maximum power has been achieved:

For short field takeoff; release the brake pedals, then control the flight path with control stick, pedals and throttle (just like an airplane).

For vertical jump takeoff; depress the collective to autorotation pitch, wait for the rotors and propeller to reach the higher rotational speeds, then release the collective lever. The rotor governor will automatically increase the collective pitch and the craft will lift off. During the transitional stage of the liftoff, the rotors will be slowing down to 100% RRPM, the propeller will be slowing down approximately 120% PRPM and the craft will be accelerating forward.

For Flight: Reduce the power setting after a safe altitude has been achieved. The controls and the craft will perform exactly like an airplane.

For landing w/ power, establish a descent path by adjusting the throttle and elevator trim tab..

For a roll-on landing perform a normal airplane type flare, by pulling back on the control stick and thereby cause the elevator to lower the tail.

For a vertical landing use a steeper descent path then apply power and flare at elevation. This causes the rotors to have a rearward component to their thrust and the propeller to have a slight upward component to its thrust. When forward motion has been halted, reduce engine power, maintain a slight tail down attitude with control stick and descend using collective and large amount of energy stored in heavy tip weighted rotors.

Landing w/o Power: Must land like plane, with forward speed to have airflow over tail control surfaces. Consider 2 engines and reserve fuel.

Setup glide slope.

To flare apply backward longitudinal cyclic and increase collective.

Objectives:

Easier and Safer to Fly:

Symmetrical handling characteristics:

The symmetry of the two counter-rotating rotor disks eliminates the need for a tail rotor [CAA PAPER 2003/1 ~ Helicopter Tail Rotor Failures]. This reduces the demands on the pilot in coordinating the cyclic and pedal. The yaw function should be similar to that of a plane. This is noted in an early Kaman brochure where it was mentioned that 'The twin intermeshing rotors produce a symmetrical air flow which is a definite advantage in crop dusting and spraying. The counter rotating intermeshing rotors completely eliminate the swirl pattern that is set up in the down draft created by a single rotor helicopter.

Also mentioned was that in 1948 the Kaman K-125 was flown by a housewife with only 2 hours of ground instruction and 36 minutes of dual instruction.

Governor: To eliminate low rotor speed. This is the second highest cause of helicopter fatalities, the highest being wire strikes.

Low disk loading & very large tip weights: To allow for a slower entry into autorotation. A slower descent rate. A small coning angle, No cyclic controls, therefor greater clearances between rotor blades. More energy stored in rotor disk for use in the flare.

Flight Controls: The rudder and elevator control yaw and longitudinal pitch. Roll is handled by differential collective between the two rotor disks.

Reliability: Where possible, components should be designed for gradual and observable deterioration thereby minimizing catastrophic failure.

Miscellaneous: The intent is to add low rpm warning, low fuel warning plus other electronic flight and power train sensors.

Uncommon Components:

►Intermeshing Configuration: To give symmetrical handling characteristics and thereby eliminate the need for a device to counteract the rotor torque.

►Power Splitting: The pilot's throttle controls the total amount of power being produced by the engine. The planetary reducer automatically splits this power 50/50 between the rotor disks and the propeller.

►Rotor Governor: The rotor governor automatically controls the collective pitch of the two rotors so as to maintain a constant 100% (operational) RRPM.

Make similar to SynchroLite so that there is a commonality of some components etc.

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Last Revised: December 11, 2003