E-Props carbon ESU spacers

Propellers are not always positioned right on the engine at the edge of the cover. Sometimes the engines come outside the cover, and sometimes are inside.
Other propellers manufacturers propose aluminium spacers if the engine is inside the engine covers, in order to space the propellers from the engine fairings.
But aluminium spacers are expensive, very heavy (20 g/mm) and needs many bolts (which can make vibrations).

Since 2008, E-Props has developed and sells an exclusive system to replace the usual aluminium spacers : CARBON ESU SPACERS.
✗  E-Props ESU spacers are ultra-light (13 times lighter : 1,5 g/mm instead of 20 g/mm for an aluminum spacer).
✗  E-Props ESU spacer option is free of charge, regardless of the chosen length.
✗  E-Props ESU spacers are a part of the hub, easy to install (no unnecessary screws and bolts, thus avoiding vibrations).
✗  Orders are easy using the interactive drawings published by E-Props.

The advantages of E-Props carbon ESU spacers

✗  Mass gain
Mass in grams of the E-PROPS carbon spacer V20 range = only 1.5 g/mm, including screws and bolts
. This is to be compared to the 20 g/mm of an aluminium spacer with screws and bolts.
Example for the extension of a 120 mm on the Savannah ultralight :
– mass of the carbon spacer = 120 mm x 1.5 g/mm = 0.180 kg
– mass of an aluminium spacer = 120 mm x 20 g/mm = 2.4 kg
=> a gain of 2.2 kg only on the Savannah’s extension function!

✗  Money saving
E-Props extended hubs are at the same price as standard hubs. So there is no need to buy an extra spacer.
For example, an aluminium spacer for Savannah (120 mm) can cost up to 300 EUR…
=> a nice money-saving for E-PROPS customers.

✗  Exist in 38 lengths
E-PROPS has developed an automatic machine that takes out the spacers at the desired length.
The E-PROPS V20 carbon spacer system is available in 38 lengths, from -20 to +170 mm, in 5 mm steps. This ensures that you will find exactly the right length for your assembly. And it’s really easy to find the spacer you need => Spacer Length : measure to take

✗  Gearbox protection
If too much mass is attached to the gearbox unit, its service life is significantly reduced. Heavy propellers create a high risk of breakage of the gearbox unit.
Reducing the mass of the spacer limits this risk.
ROTAX does not recommend the use of propeller extensions longer than 120 mm.
This of course applies to aluminium spacers, as the weight of the spacer (more than 2 kg) would then be too high for the gearbox.
E-PROPS, with its ultra-light carbon spacers (example: the 170 mm spacer weighs only 255 g), allows solutions to keep the propeller away from the engine fairings up to 170 mm, without risk to the gearbox.

✗  Reduction of vibrations
The propeller is directly centred by the hub. This avoids spacer stacks and the various screws and pins, which often generate vibrations.
A simple and straightforward system like E-PROPS greatly reduces the risk of vibration.

✗  A reliable and durable system
E-PROPS hubs, whether standard or with spacer, are extremely strong.
Material: 100% carbon + high temperature epoxy resin
Injection according to the RTM (Resin Transfer Molding) process
Compact volume hub: for minimum drag and optimised engine cooling
TBO : up to 4,000 hours for certified propellers models

✗  Simple assembly
The E-PROPS spacer allows quick and easy assembly, with the minimum number of parts. The centering pins, mandatory on ROTAX 9 series engines, are integrated in the carbon part, whereas they have to be added on the aluminum spacers (weight of the 6 Rotax pins = 125 g).

E-Props does everything in its power to design and produce ultra-high-performance, ultra-light propellers that have been thought through down to the smallest detail to offer the utmost in safety and flying comfort.