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 aerobatics.
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 Osprey (Bell Boeing V22).
As the Osprey, 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.
In the following arrangement the two crankshafts of the OPRE Tilting engine drive, through sprockets and toothed belts, two conventional counter-rotating big diameter propellers mounted at the same side of the engine and revving at substantially lower revs:
The synchronizing gearwheels run unloaded.
The basis of the engine is perfectly rid of inertia and combustion vibrations.
The total gyroscopic rigidity is zero.
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:
The PatATi Portable Flyer looks like a scale-down of the Osprey (Bell Boeing V22):
A tooth belt (click here for more) synchronizes the two counter-rotating crankshafts:
Click on the above image for the PatATi_First_Run video or click here to open the video in youtube
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 a man's body is not adequate to lift its weight.
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.
With a pattakon Portable Flyer secured onto his shoulders / torso, a man can fly like a bird.
Are the previous anything more than scientific fiction?
According several articles and videos published in the Internet, Yves Rossy / Jetman already "flies with the grace of an eagle, and the subtle body movements he uses to maintain flight - and perform his loops, rolls, and other maneuvers - mimics a bird of prey".
With only an altimeter and timer, Rossy uses his skin and ears as airspeed indicators.
"You feel very well, you feel the pressure," Rossy says, "you just have to wake up these senses. Inside an airplane we delegate that to instruments. So we are not awake with our body."
As Rossy says : "I am the fuselage, and the steering controls are my hands, head and legs"
Rossy's Jetpack (a carbon-fibre wing fixed to the rider's back and mounted with kerosene-powered jets) has several issues yet to address: no take-off capacity, no landing capacity, no hovering capacity, very small range, less than poor fuel efficiency, limited top horizontal speed (big and fixed frontal area), need for a helicopter or airplane for the initial lift at a high altitude, extreme ownership and running cost.
The pattakon Portable Flyers can do a lot more.
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: