Two counter rotating crankshafts share the same combustion chamber keeping the basis perfectly rid of inertia vibrations and of combustion vibrations.
The basis (i.e. the rider / pilot) needs not to provide any reaction torque (not even at extreme changes of revs and load).
With the symmetric counter-rotating propellers (and crankshafts), the total "gyroscopic rigidity" is zero, i.e. the rider can "instantly" (as instantly as with the propellers stopped) vector the thrust to the desirable direction (click here for a youtube video / demonstration of the gyroscopic rigidity of a set of parallel flywheels).
The above make "a true neutral propulsion unit": neither vibrations, nor reaction torque, nor gyroscopic rigidity; only a force that can "instantly" and effortlessly be vectored towards the desirable direction.
As aerodynamic "controls" the rider / pilot can use his legs, hands and body, just like the wing-suiters do. A wing-suit fits with the Portable Flyer, especially for long flights and fast acrobatics.
With 1m diameter propellers and 100Kp (220lb) total (including the rider and the fuel) take-off weight, the propeller "disk loading" is only half of the propeller "disk loading" of the Ossprey (Bell Boeing V22).
As the Ossprey, the Portable Flyer is capable for "vertical take-off / landing (like a helicopter) and for long distance flights at high speed and low fuel consumption (like an airplane).
OPRE Portable Flyer
The radius of the unconventional (wide Vee) intermeshing propellers is substantially longer than the distance between the two crankshafts.
Crosshead architecture with four-stroke-like lubrication.
Pulling connecting rods providing additional time for the combustion.
Here is an Opposed-Piston PatTilt Portable Flyer (conventional propellers):
In the PatTilt (or Tilting Valve) engine (click here for more) a valve (the tilting valve) is secured on the small end of the connecting rod.
The piston has a properly formed port (the piston port) that sealingly fits with the tilting valve.
The tilting valve opens and closes the piston port allowing, or stopping, the communication of the spaces at the two sides of the piston port.
The geometry of the "tilting valve / piston port" defines the timing of the opening and closing of the piston port.
The "pulling connecting rod" architecture provides additional time for the combustion.
Rid of reed valves and of rotary valves, simple (i.e. reliable), compact and lightweight.
Rid of reed valves and of rotary valves, the PatATi engine (click here for more) has asymmetric transfer and asymmetric intake:
the intake ports communicate with the crankcase through piston ports controlled by the connecting rod asymmetrically;
the crankcase communicates with the combustion chamber through conventional transfer ports and through asymmetric transfer ports; the asymmetric transfer ports are controlled by the piston and are disposed in series with respective piston ports controlled by the connecting rod.
Simple (as simple as it gets?), reliable, efficient and lightweight.
When a child begins riding a bicycle, it progressively learns how to react properly to the signals from the eyes and the body (i.e. on how to keep the control).
Just like driving a bicycle, the eyes / body / brain of the rider / pilot of a Portable Flyer are the sensors and the control system: the rider soon discovers the way to react properly and to keep the control. For the Portable Flyer is a true neutral propulsion unit: neither vibrations, nor reaction torque, nor gyroscopic rigidity, only a force: a force that can "instantly" and effortlessly be vectored towards the desirable direction.
In a Flyer it is better to be used the body of the rider as the main sensing and controlling equipment (birds like), than developing and paying and carrying stabilizing and flight management systems.
The birds, the bats and the bugs fly because their bodies can provide adequate power for their weight.
The power provided by the body of a man is not adequate to lift his weight.
The weight of a man cannot be decreased.
What a man needs, in order to fly, is neither a vehicle, nor sensors, nor servomechanisms, nor control units, nor transmission shafts, nor differentials, nor gear-boxes, not even a seat.
What a man does need, in order to fly, is power provided in a true neutral and manageable way. The body is: the vehicle and the sensors and the control unit and the servomechanisms and the landing system, just like the bodies of the birds, bats and bugs.
All a man needs, in order to fly, is a Portable Flyer secured onto his shoulders / helmet.
Time will prove whether flying with such a Portable Flyer is more difficult than riding a bicycle.
Click on any of the above images to enlarge or to download the respective windows "exe" controllable animation.
OPRE Propulsion Unit
This propulsion unit is: direct injection Diesel, lightweight, vibration free with minimized total momentum of inertia enabling way easier direction change.
It improves the lightweight, the durability, the safety, the stability and the easy handling of small airplanes.
The maximal total range increases, while the emissions and the fuel cost decrease.
A forwards force and the weight of the engine/rotors are the only loads the frame of the airplane receives from the propulsion unit.
A sudden change of the engine load (WOT to stall, for instance), or a misfiring, cannot destabilize the airplane.
Click on the image below for the QuickTime 5 MB video: