:: Raptor X4 150cc, 4 Cylinder, 4 Stroke Engine ::

* Under development or yet to be confirmed.

Trilobe Stroke.

How Trilobe's Stroke Each Piston 3 times per revolution.

Main Gear & Trilobe shown in position. (2400cc engine)

With Piston Plates, Bearing and Bearing Casings in place.

(second Trilobe and Reverse Gearing is not fitted)

Raptor X4-150 v2.6

RHS

Top view

Aft view (Prop side) Raptor X4-150 v2.6

A Revetec engine is like no other engine !

As it uses an Australian designed & patented ground breaking CCE technology, that has replaced the 100 year old Crankshaft design with a Coaxial Contra-Rotating Trilobe system, that Strokes each Piston Six times (3 up & 3 down) per 360° revolution of the engines Centre drive shaft (CDS), the CDS in turn produce Three Combustion's per cylinder, per Two revolution of the CDS.  Where a conventional 4 stroke crankshaft ONLY produces One Combustion stroke in Two revolutions!

This unique engine design has Two Contra-Rotating Propellers directly driven off internal gearing, and will provide between 6% and 16% more Thrust (according to Wikipedia) than a conventional single propeller engine!

Vastly more important is the fact that Contra-rotating propeller totally eliminates torque/riser twist caused by ALL single propeller engines! 

Contra Rotating Propellers were invented in 1909, but never took off as at the time Jet engines started to replace piston powered engines.

Unlike many other engines in its category, the power curve of the Raptor X4-150 is as yet unknown, due to the uniqueness of it's Contra-rotating propeller  drive shafts.

As the Raptor X4-150 engine will not be revving past 3'500rpm, it should pass D.U.L.V. certification, this indicates it will comply with the noise standards, environmental and technical standards set by the toughest certifying body in Germany. 

Due to the engine lower operating speed (*3'500rpm), this should be one of the quietest PPG engines available, this Australian invented engine revs at 1/3 of the speed of a conventional 2 and 4 stroke engines, that operate from 7'000~12'000 rpm.

The Raptor X4-150 will come standard with a Kestrel or Rhino cage. For more info on the Cages visit our Paramotor Cages page.

To get a better understand how this unique internal combustion engine works, click here to see the companies Technical workings of this engine technology.

Forward (BACK)

LHS

Bottom view

Introduction

Contra-Rotating Drive systems for full scale airplanes have been known since World War II, but since then, despite their many advantages, they have only seen occasional use in certain military applications.

This has been for two reasons.

1. When Contra-Rotating Propeller Technology was being developed the jet engine was also being introduced, and while Contra-Rotating Propeller Systems had efficiency advantages over jet engines, jet engines held out the promise of more performance, and airplanes that could fly higher and faster than the speed of sound.
2. In the commercial airline industry the ability to fly jets at great heights, and with less cabin noise, also won out over the efficiency benefits of Contra-Rotating Systems.

Benefits

However, for pattern flying the advantages that a Contra-Rotating System offers are considerable:

1. Contra-Rotating Propellers eliminate the gyroscopic effects that exist when flying with a single propeller. Gyroscopic effects cause an airplane to yaw whenever the PPG throttle is applied. The more throttle that is applied, the greater this yawing effect. Contra-Rotating systems eliminate this, so there is no yawing of the airplane whenever the throttle is applied, and consequently, no radio mixing is required to remove it.
2. Contra-Rotating Propellers significantly reduce the maximum torque that goes into the PPG Cage. With a single propeller system, the torque that goes into turning the propeller also reacts out against the engine mounts and the Cage of the aircraft, so if the engine is generating 5 Nm of torque to turn the propeller, the engine is also trying to rotate the cage/quad with this same 5 Nm of torque. Whereas, with a Contra Rotating System the torque is divided by the gear ratio of the gearbox, so if the Drive is using a gearbox with a 3:1 gear ratio, then the torque into the Cage/fuselage is only 1.6 Nm. This means that an airplane with a Contra-Rotating Propeller System won’t change aileron trim on the downlines, or when entering a spiral, or when coming in for a landing. With a single propeller system all of these situations will require different amounts of trim, which all need to be mixed in. However, with a Contra-Rotating Propeller System the trim never changes, so no mixing is needed.
3. Contra-Rotating Propeller Systems eliminate the P-Factor effects that tend to yaw an airplane when the thrust line doesn't coincide with the flight path of the airplane (this effect reverses when flying a winged airplane inverted, so while right thrust in the engine can compensate somewhat when the airplane is flying right side up, rudder to throttle mixing is needed to compensate when the airplane is flying inverted). With a Contra-Rotating System no right thrust in the engine is required, and consequently no mixing is needed.
4. Contra-Rotating Propeller Drive Systems have two propellers that provide more than twice the braking power that a single propeller system provides so ESC engine braking isn't needed. Also, since Contra-Rotating Drive Systems have propellers that spin in opposite directions, each propeller generates an equal, but opposite braking torque, which eliminates the aileron trim effect that is seen on downlines when ESC engine braking is used with single propeller setups.
5. Contra-Rotating Propeller systems are 15% to 20% more energy efficient than equivalent single propeller systems. This is because the air passing through the blades of the propellers is accelerated twice in order to generate thrust, instead of a single time as it is with single propeller systems. This means that each of the two propellers in a Contra-Rotating System is doing half the work that the propeller in a single propeller system needs to do so they can do their work with fewer viscous losses, and fewer losses due to radial air flow along the length of the propeller blades.
6. The air that goes through the first propeller in a Contra Rotating System acquires a rotational twist, which is then cancelled out by the reverse rotation of the second prop. This has two benefits. The rotational energy in the air is recovered as useful thrust, which increases propeller efficiency, and the air exiting the rear propeller flows straight back (over the fuselage in forward mounted engine, without rolling and yawing the airplane as it blows against the wings, the stab, and the rudder). This effect is most pronounced when the plane is flying slowly, such as during take-off, or at the end of long verticals. A Contra Rotating system compensates for these effects so take-offs are straight and true, and the airplane tracks straight when flying slowly after long vertical uplines.