The E-Props Company
E-PROPS DETAILS
The E-PROPS Company
195, Route de l'Aviation
ZI Aérodrome de Sisteron
04200 VAUMEILH - France

The best way to reach our team is by email : helices@e-props.fr


E-PROPS : Fixed Pitch Propellers for engines 7-50 kW dia 115 to 160 cm



✗  Hi-Tech full carbon propellers, fixed pitch
✗  The lightest propellers in the world : up to less than 420 gr for a 2-blade propeller !
✗  For gear-drive engines and electric engines from 7 to 50 kW
✗  Each model available in : 2-, 3-, 4- and 6- blades
✗  Diameters : from 115 cm to 160 cm, each 5 cm
✗  Models each 0,5° pitch
✗  Tractor and pusher configurations
✗  Available in both rotation senses : CW and CCW
✗  Click to see : Traction / Torque curves of this range

✗  Very strong : full carbon, very high fibers ratio, HCF process, leading edge protection
✗  ASTM F2506-13 certified

✗  Made in France since 2008
✗  E-PROPS production : 45.000 blades / year
✗  Propellers sold in more than 80 countries

E-PROPS propellers

TECHNICAL DATA

1- Design
2- Fixed pitch propellers models
3- Weight
4- Blades
5- Blade's foot
6- Finish
7- Tips
8- Leading edge protection
9- Moment of Inertia
10- Balancing
11- Quality
12- Repair
13- Spare Blade
14- Tracking / Dynamic gap
15- Drilling
16- Tightening torque
17- Max RPM - Sense of Rotation
18- Max Power
19- Maintenance
20- How to choose an E-Props fixed pitch propeller ?
21- Propellers Pitch


1- Design


Propellers of 3rd generation : efficient, ultra-light, quiet and very strong.
Made in France since 2008 : see page the E-PROPS company.
Adapted diameters and blades' numbers defined according to engines and reducers.
See here the TRACTION / TORQUE CURVES per MODEL.
The secret of their exceptional performances ?
- Extensive research of the E-PROPS design department, with many tests campaigns on wind tunnel et the development of an exceptional software (LmPTR©).
- A manufacturing process which allows a very lightweight, this a high reactivity.
- Specific E-PROPS designs with high CL profiles.
- SCIMITAR shape : more thrust, less inertia, fuel economy and noise reduction.
Informations on E-PROPS design, see page DESIGN and TESTS

2- Fixed pitch propellers models


Fixed pitch E-PROPS are the lightest and strongest propellers on the market.
Characteristics of these models :
- Exist in 2- / 3- / 4- / 6-blades
- diameters : all 5 cm, from 115 to 160 cm
- all in CW and CCW rotation sense
- pitch all 0,5°
Click to see : Traction / Torque curves of this range

3- Weight


E-PROPS are the lightest propellers in the world.
Example:
- 2-blade diameter 125 cm = 420 g
- 3-blade diameter 130 cm = 780 g
- 4-blade diameter 130 cm = 1120 g
- 6-blade diameter 160 cm = 2080 g
That is 30 to 60% less than other composite propellers on the market.
Advantages of a light propeller, see here : ULTRA-LIGHT PROPELLERS

4- Blades


E-PROPS are full carbon propellers.
Optimum use of carbon fibers braid and epoxy resin to obtain ultra-light and very strong blades.
The HCF (Helical Continuous Fibers) process, specifically designed by E-PROPS, ensures an exceptional strength of the carbon braid (like a sock) + epoxy resin blade, from leading edge to trailing edge, from blade's foot to tip.
Manufacturing process : Resin Transfer Molding (RTM).
Foam core (D-Box).
UV High Resistance epoxy resin
Very high carbon fiber ratio : 63%
See page MANUFACTURING and page ULTRA-LIGHT PROPELLERS

5- Blade's foot


The E-PROPS fixed pitch propellers are dismountable.
The blades are in two or three sectionnable parts, as a puzzle, very simple to assembly.
The assembly is correct when the stickers are on the same side.
Thickness of the blade's feet of a 2-blade model : 38 mm

6- Finish


Finish with shiny polish.
The carbon braid remains visible; each blade is unique.
No paint, no varnish, no gel-coat, because those finishes are very polluting, and the E-PROPS company respects an approach of eco-management.
Furthermore, paints, varnishes and gel-coats do not allow to easily and properly repair the blades, in case of impacts.

7- Tips


E-PROPS has made extensive research on the blades tips, with many tests on different configurations : rounded, cut with angles, with upper or lower winglets...
The best performances and the lower noise are reached with a straight cut tip.
See here : TIPS

8- Leading edge protection


All E-PROPS fixed pitch models have an internal protection in the blades : injection at the leading edge of a special resin with Nanostrength® additive shock.
In special cases, it is recommended to an extra protection on the blades leading edge, in order to reinforce it, with a polyurethane protection tape used on certified helicopter rotor blades.
See here : LEADING EDGE PROTECTION

9- Moment of Inertia


Strict respect of the Moment of Inertia limitations given the engines manufacturers.
Moment of inertia of each model calculated then verified on the tests bench.
For example, MOI about 500 kg.cm² for a 125 cm diameter 2-blade model
See details here : MOMENT OF INERTIA

10- Balancing


The E-PROPS propellers are precisely balanced at workshop.
The team is using an electronic bench to balance the propellers.
Please note : the blades do not necessarily have the same weight, but must have the same static moment to be well-balanced.
See explanations : BALANCING

11- Quality


The E-Props propellers are designed, manufactured and tested to meet the requirements of the aeronautical standards.
Quality and safety are ongoing concerns for the E-PROPS company, throughout the design, procurement, manufacturing, testing and marketing of all its products.
See page QUALITY

12- Repairs


Small impacts can be easily repaired (epoxy resin without paint, varnish or gel-coat).
If an incident or a shock require an important repair, this one must be realized by E-PROPS or an agreed repairing center.
A repair kit is available.

13- Spare Blade


At E-PROPS, it is possible to change only one blade.
Traceability is very important at E-PROPS :
✗  A RFID chip is inserted in each blade, for technical monitoring.
✗  Model reference on each blade.
✗  Unique serial number on each blade.
This serial number allows perfect quality control and makes possible to replace a single blade without having to return the whole set.

14- Tracking / Dynamic gap / Gap from the frame


✗  Max static tracking : up to 10 mm
Tracking is not important if there are no vibrations.
See page TRACKING
✗  Dynamic gap : up to 20 mm (the blade can move towards the engine at max power).
This gap is depending on the engine assembly, on the cage and on the silent-blocks.
✗  Gap from the frame : it is recommended to part the propeller from the cage of minimum 40 mm.

15- Drilling


Each propeller has a hole to adapt to its engine and gearbox.
For the range of fixed pitch propellers, here are the available drillings :
centring = 25 mm
Standard drillings :
✗  6M8d75
✗  6M6d50
✗  6M6d60
Optional drillings (with extra charge) :
✗  4M6d50
✗  4M6d60
✗  4M8d63
See page HUBS DRILLINGS


16- Tightening torque


The screws tightening must be done with a torque wrench; torque value depending on the screws :
Screws 6 mm = 8 N.m
Screws 8 mm = 16 N.m

17- Max RPM - Sense of Rotation


The maximum rotational speed (at the propeller = maximum engine speed / reduction ratio) depends on the propeller diameter, the number of blades and the blade pitch adopted.
It is indicated on the Traction / Torque curves of this range

The rotation sense of a propeller is always defined seen in the wind made but the propeller :
- clockwise sense (CW)
- counterclockwise sense (CCW)

18- Max power


The maximum power the propeller can absorb depends on each propeller model.
It is indicated on the Traction / Torque curves of this range

Warning: on electric motors, the maximum rpm of the motor very often depends on the battery voltage.
The maximum power reduces the battery voltage and therefore the maximum rpm.
This data must be taken into account to define the desired propeller model on the curves.

19- Maintenance


Maintenance is simple :
- Before each flight: visual inspection of the propeller (particularly check the leading edge) and check the screws tightening.
- Every 50 hours of flight or every 3 months : check of the screws tightening.
Cleaning of a carbon propeller is made with a sponge, with some water with soap, or with a product for windows cleaning.

20- How to choose an E-Props fixed pitch propeller ?


Thrust and torque curves => SEE HERE

21- Propellers pitch


Propellers pitch => SEE HERE



Languages
English Francais
Fixed Props for engines 7-50 kW dia 115 to 160 cm
Adjustable Props for engines 50-115 kW dia 145 to 205 cm