The E-Props Company
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 :

E-PROPS : Titanium or Nanostrength Leading Edge Protection

The leading edge of the propellers blades needs a reinforced protection, against stones impact or other projectiles, and sometimes against erosion possibly generated by rain and sand.
E-PROPS proposes two solutions to reinforce its carbon blades : a Titanium leading edge protection and a leading edge protection in Nanostrength shock addtive.



Each E-Props carbon propeller which has no Titaniumm leading edge protection has a protection with Nanostrength® additive shock [1] in the epoxy resin.
Made by ARKEMA, Nanostrength® are new innovative additive to reinforce epoxy resin, with high energy absorbing capability.

The resin with Nanostrength® is injected in the leading edge during the manufacturing of blade in RTM (Resin Transfer Molding). It is completely integrated in the blade, without unsticking risks or materials incompatibility, and with a perfect respect for profiles.
This additive has been selected because the leading edge protection of the E-Props propellers range is more resistant as Steel or Inconel 5/10e (see COMPARATIVE TESTS below), and far more easier to repair in case of shocks.

It has been developped for the UAV with Rotax 914 that E-PROPS equips since 2008, and for ultralights and aircraft which are flying in Africa, on non-prepared airfields in laterite.

E-PROPS customers prefer this type of leading edge reinforcement to Steel or Inconel one, because :
- integrated in the blade : no risk of detachment
- no part in Steel or Inconel = no risk of galvanic corrosion
- reinforcement all along the leading edge
- no extra weight on the tips : smaller Moment of Inertia
- possibility to easily repair the leading edge protection, even on a big impact (when a metallic leading edge must be changed - or the whole blade) : every pilot can make this repair himself, with the E-PROPS repair kit (available in this e-shop)


Comparative tests have been made between a Nanostrength® leading edge protection and a Inconel 5/10e with a system called "Charpy pendulum" :

eprops mouton charpy

In 1901, the French engineer Georges Charpy proposed the "pendulum sheep" still used today.
The purpose of the Charpy test is to determine the impact resistance of materials. It allows to measure their resilience, that is to say the resistance of a material to shocks.

The E-PROPS team has made its own Charpy pendulum :

eprops mouton charpy

Some series of tests have been made to compare a Nanostrength® resin leading edge and a 5/10e Inconel leading edge.

eprops blindage

Tests Video

eprops blindage helices

shocks after the tests

eprops blindage helices

tests results

eprops blindage helices

stone of the maximum shock (1,12 gr)
speed of the stone at impact : 155 m/sec

eprops blindage helices

Deepth of the maximum impact :
- leading edge Inconel 5/10e = 2,1 mm
- leading edge resin Nanostrength® = 0,9 mm

The tests results show that :
1/ The leading edge resin Nanostrength® present much less important damages than leading edge 5/10e Inconel.
2/ The protection with shock additive is integrated all along the leading edge, because the shocks do not happen only at tips.
3/ The leading edge with Nanostrength® shock additive does not lead either unsticking or electrolytic couple.
4/ The possible impacts are very easy to repair. A repair kit is available on this e-shop.

[1] Nanostrength® are additives that reinforce the epoxy resin. They are developed and produced by ARKEMA and are characterised by :
- increased mechanical resistance without loss of the essential properties of the matrix
- highly reproducible nanostructuring
- mastery of the rheology of materials
- compatibility and load dispersion
Nanostrength®, nanostructured additives with a high capacity to absorb kinetic energy, find applications in many markets: advanced materials for the aerospace sector, sports, the automotive industry, etc.


In some specific cases, for example :
- seaplanes
- very long flights under very heavy rains (like monsoon) at high engine RPM
- flights at the water's edge and on the beach
it could be interesting to put an extra protection on the blades leading edge, when they have no Titanium leading edge protection.

eprops on the beach eprops on beach
eprops on the lake
eprops on sea
in those case, protect the blades leading edge is interesting !

For those types of flights, E-PROPS recommands to add a polyurethane protection tape.
This polyurethane protection tape is made from very high performance elastomer, resistant to erosion, abrasion, punctures, minor impact damage and tears.
Its formula is also resistant to ultraviolet light. Its thickness is 0,36 mm.

This specific polyurethane protection tape is used on certified helicopter rotor blades.
This protection tape does not impact the aerodynamic performances of the blades. The E-PROPS team has made many tests which all show that the performance gap between a blade with a polyurethane protection tape and a blade without this tape is not measurable.

Since 1rst of January, 2019, E-PROPS equips all propellers blades for Ultralights / Aircraft (when they have no Titanium leading edge protection) with this polyurethane tape (as standard). This option is free.

This tape is clear and adhesive on one side. It can be painted or applied on painted surfaces.
The relative rigidity of this material makes it very easy to install and change.
It is available on this e-shop, in kits of different lengths.

eprops ruban protection blindage helices


The E-Props propellers for engines 50-115 kW, diameter 155 to 195 cm, include a Titanium protection on the blade leading edge, 5/10e thick.

TITANIUM is the ideal material for blade leading edge protection thanks to its mechanical characteristics :
- specific resistance outpacing Aluminium and Steel
- expansion and elasticity close to carbon – epoxy
- exceptional corrosion resistance (in particular in marine climate)
- Titanium is twice as light as Steel or Inconel

- if the Titanium leading edge protection is damaged, E-Props can change it, without having to change the whole blade.
- the blades with a Titanium leading edge are specifically manufactured : the mould integrates a place (respecting the blade profiles) where E-Props comes to glue the Titanium leading edge protection.

eprops pale blindage TITANE
E-Props blade with Titanium leading edge protection

English Francais
Fixed Props for engines 7-50 kW dia 115 to 160 cm
Adjustable Props for engines 50-168 kW dia 120 to 209 cm