HELICEUROPE choose propeller paramotor ultralight

TO DETERMINE YOUR PROPELLER CHARACTERISTICS

SOME CALCULATION MODULES TO HELP YOU

A propeller is a mechanical device which produces a thrust parallel to its axis of rotation when it turns.

A propeller has two, three or four blades. The angle of attack is given in degrees against the propeller rotation plan.

The central part of the propeller is called “hub”. The hub is perforated by four or six holes depending on the engine model and is fitted on an axis used as pivot.

The propeller acts like a screw which is pulled through the air when it turns just like a screw is pulled through the nut of a bolt. The virtual distance that a propeller covers, in a full rotation, is called “ propeller pitch”.

The reducer is a device that transmits a rotation movement with a speed reduction. In particular it prevents against a blade speed over the speed of sound (1190 km/h). For instance: for a 115 cm propeller set up on a "SOLO" engine with a rotation speed of 6500 rpm, the speed of the end of the blades would be 1408 km/h; The reducer (1:2.5), reduces the speed down to 563 km/h.

Rotation sense can either be in the direction of the hand of a watch, in this case it is known as “clockwise” and conversely “anticlockwise”. The rotation sense is related to the engine type and thus to the engine manufacturer.

TO DETERMINE YOUR PROPELLER CHARACTERISTICS :

1. Trademark and model of your engine: consult your ultralight technical documentation or the maker label on your engine.

2. Engine rotation sense: stand front of your propeller to determine your engine rotation sense. Usually, the engine rotation is anticlockwise except “TOP 80” and “raket” engines , for which the rotation is clockwise.

3. Propeller length : consult your ultralight technical documentation or measure your propeller.

4. Reducer ratio : consult your ultralight technical documentation or measure the diameter of the roller connected to your engine crankshaft and the diameter of the roller on which your propeller is fixed. Now calculate your reducer ratio by dividing the diameter of the roller of the propeller by the diameter of the roller of the driving crankshaft.

5. Angle of attack of your blades: Using a protactor, measure your blade angle compared to your propeller rotation plan. This measurement is carried out at 15 inches from the propeller centre ie 38 cm

6. Propeller pitch : you can manually calculate your propeller pitch (in inches) by applying the following formula:
Pitch = 239,39 X Tangent (angle of attack X p / 180) / 2,54 or use the calculation module below.

7. The number of holes: count the number of clamp holes in the hub of your propeller.

WHICH DRILLING FOR YOUR HUB


HELICEUROPE drilling TYPE	A number of holes	Diameter of the bolts of fixing	Pitch circle diameter B	Between axis A
4-60	4	6 mm	6,5 mm	60 mm
4-63	4	8 mm	8,5 mm	63 mm
6-55	6	6 mm	6,5 mm	55 mm
6-50	6	6 mm	6,5 mm	50 mm
6-75	6	8 mm	8,5 mm	75 mm

SOME CALCULATION MODULES TO HELP YOU:

Cm to inch converter (1 inch = 2.54 cm) cm inch (es)

Pitch Calculation according to angle of attack:
angle of attack degree (s) inch (es)

Theoretical thrust calculation:

Propeller pitch= inches
Maximum engine rotation = Revolutions Per Minute
Reducer ratio =
Propeller length = inches
Watt

Warning: to change the propeller model calculate your current propeller theoretical thrust. Then make change the parameters to obtain an equivalent thrust. The variation will never exceed 10% to prevent any damage on your engine.