Propellers Design - LUKY Software - Moment of Inertia - Performances - Change of propeller ?
It currently employs 20 aeronautical engineers and technicians. , who carry out theoretical calculations, modeling and prototype development, followed by ground and flight tests.
Jérémie Buiatti developed the LUKY software specifically for designing innovative, high-performance propellers, and masters all the technical aspects involved in developing high-performance propellers.
2 - Propellers design / Tests / Theory / Moment of inertia
3 - E-Props: Efficiency / Lightness / Noise reduction
4 - Why change propeller ?
1 - E-Props LUKY software
Profiles optimization using evolutionary algorithm
LUKY software models the behavior of an E-Props propeller on a given engine, from an aerodynamic and mechanical point of view, including vibration analysis and service life calculation.
It enables the E-Props design office to develop blade profiles adapted to each aircraft - engine - application.
=> See description here: LUKY SOFTWARE
This software is a model of the type lifting line for the speed of execution, in order to allow the exploration of the domain of possible propellers with the help of an evolutionary algorithm (metaheuristic), in order to automate the search for propeller solutions (mechanical and aerodynamic dimensioning) for a given problem.
Thousands of hours of code and tests by highly specialized engineers were required to develop this software.
LUKY represents an exceptional step forward in the development of equally exceptional propellers.
2 - Propellers design / Tests / Theory / Moment of inertia
E-PROPS propellers are designed to offer the best possible performance, while being both ultra-light and extremely strong.
✗ Propeller testing is essential to validate calculations and models, and to compare performance with other propellers.
Ground test facilities
Every E-Props propeller model is tested on the ground to confirm its performance, mechanical strength and compatibility with the intended engines, before any flight testing begins.
Terminator — laser-scanning dimensional inspection
Every blade and component is checked with the Terminator laser-scanning system: high-precision laser sensors measure the actual surface geometry of the part and compare it, point by point, with its digital reference model. This 3D control is applied systematically, before and after mechanical testing, to confirm that no dimensional drift has occurred during fatigue, vibration or impact testing.
Traction (thrust) test bench
An instrumented ground bench fitted with a traction (thrust) measurement system, built around a 40-tonne hydraulic cylinder. It is used to verify the static thrust delivered by a propeller/engine combination and to validate design calculations before flight testing.
Fatigue test bench
This bench stresses a blade in alternating bending to reproduce the torque delivered by the engine. It is used to establish the real Mean Time Between Overhaul (MTBO) of a propeller, rather than relying only on calculated estimates.
RESONATOR — torsional vibration test bench
For the development of propellers intended for direct-drive engines, E-Props built a dedicated vibration test bench able to reproduce, with high fidelity, the vibratory loads generated by aeronautical piston engines — in particular large 4- and 6-cylinder units. The bench combines a torsion bar, a flywheel, an electric servo-motor and a high-precision digital encoder, reproducing the vibratory component of engine torque up to three times the levels measured in real operation. Current objective for the ASCALON range: to demonstrate an unlimited service life, in line with the requirements of EASA CS-P §370.
Chicken Gun — bird-strike impact test bench
Bird impacts are among the most demanding events a propeller can encounter in service. To assess blade robustness under such conditions, the aerospace industry uses a "chicken gun" to simulate a controlled impact with a bird-sized projectile at representative velocity. E-Props designed and built this bench in-house; it is used in the development and validation campaign of the ASCALON range, dedicated to direct-drive engines and currently undergoing EASA CS-P and FAA 14 CFR Part 35 certification.
SHEEVA — high-pressure hydraulic test bench
The SHEEVA bench tests the governor, regulator and calculator assemblies of the GLORIEUSE variable-pitch propeller range. It simulates real flight conditions hydraulically, so that every such component is individually validated before delivery.
Flight test facilities
E-Props' own aircraft fleet allows flight-test campaigns of every propeller model and prototype, flown from the Sisteron-Vaumeilh airfield (LFNS).
| Aircraft | Role | Seats | Engine |
|---|---|---|---|
| SKYRANGER | Ultralight, low-speed range (30–190 km/h) | 2 | Rotax 912S — 100 hp |
| PENA Bilouis | Aerobatic flight test, VNE 370 km/h | 2 | Lycoming O-360 — 180 hp |
| JODEL DR1054 | Cruise flight test, VNE 270 km/h | 4 | Lycoming O-320 — 150 hp |
The ultralight SKYRANGER, acquired in 2015, is E-Props' first flight-test aircraft: its simple tube-and-fabric structure makes it easy to fit measurement equipment (a boom under the wing for airspeed and angle-of-attack, a cockpit fitted with sensors and cameras...), and it covers a useful low-speed test range from 30 to 190 km/h.
Samy Dupland, test pilot
All flight and ground test campaigns are conducted by Samuel "Samy" Dupland, E-Props' dedicated test pilot since 2020. He has more than 5,000 flight hours of experience.
ELIAS — in-flight data-acquisition system
ELIAS is the onboard data-acquisition system designed and manufactured entirely by E-Props. Originally developed to measure propeller/engine vibration and blade strain, it now integrates a complete flight-performance measurement chain: propeller thrust and torque, temperatures, static and dynamic pressures, engine RPM, angle of attack and sideslip, vibratory loads and blade-root strain. Thousands of measurements are transmitted in real time (Wi-Fi, and 3G for flight campaigns) to an onboard computer and to a cockpit display that lets the pilot refine the flight profile according to the required test parameters.
Case study: torsional vibration on a Lycoming O-360
To illustrate how these test means are combined in practice, E-Props instrumented a Lycoming O-360-A1D engine (hollow crankshaft, internal strain gauges) with the ELIAS system (16 channels, 6.5 kHz/channel, GPS-synchronized) and compared four propellers on ground and in flight:
| Propeller | Resonance | Remarks |
|---|---|---|
| Aluminium (Sensenich, 2-blade) | ~2350 RPM | Strong resonance, within the manufacturer's restricted range |
| Wood (Hoffmann, 2-blade) | ~2225 RPM | Moderate torque level; range not currently flagged as restricted |
| Carbon, 5-blade (DUC FLAIR-2) | ~2625 RPM | Ground test only — propeller decertified by EASA, included for research purposes |
| Carbon, 3-blade (E-Props A42) | ~2250 RPM | Very slight resonance, lowest torque levels of the four propellers |
The E-Props three-blade carbon propeller, designed with LUKY's dynamic engine/propeller model and evolutionary optimization, showed markedly lower torsional excitation than the other three propellers — demonstrating, on real flight and ground data, the value of designing the propeller and engine as a single dynamic system rather than tuning the propeller afterwards.
Reference: J. Buiatti, Experimental Torsional Vibration Analysis of Different Propellers on a Lycoming O-360 Engine, E-Props, January 2026.
These test means support compliance with the applicable propeller airworthiness requirements: EASA CS-P (including the fatigue/vibration requirements of §370), ASTM standards, and FAA requirements as applicable to each market. Links to the corresponding test reports are available in the comments section of each propeller in the E-Props catalog, and additional test videos can be found on the E-Props YouTube channel.
✗ Propellers comparative tests in flight : a very interesting and complex exercise.
=> See method here: PROPELLERS COMPARATIVE TESTS IN FLIGHT
✗ To understand how a propeller works, it's essential to understand the laws of experimental physics.
=> See here: PROPULSION THEORY
✗ Moment of inertia [MOI] is a very important parameter for propellers.
=> See explanations here: PROPELLERS & MOMENT OF INERTIA
=> Rotax Service Instruction: Propeller mass moment of inertia for ROTAX
✗ Influence of propeller inertia
Jérémie Buiatti, designer of E-PROPS propellers, has taken a close interest in what happens between the engine and the propeller. He wrote an interesting article for the publications of the "Colloque de Cachan 2016" organized by the French association INTER ACTION (Association de Sauvetage Créatif du Savoir Aéronautique).
=> See this article here: "The pistons pound, the gearbox perished"
3 - E-Props: Efficiency / Lightness / Noise reduction
✗ E-Props : exceptionally efficient propellers
E-Props propellers have very special profiles and specific designs to reduce blade drag, and thus achieve the best possible thrust.
=> See description here: E-PROPS EFFICIENCY
✗ E-Props : ultra-light propellers
E-Props are the world's lightest propellers.
To understand why these propellers are ultra-light, and why the lightness of this equipment is essential:
=> See explanations here: E-PROPS: ULTRA-LIGHT PROPELLERS
✗ E-Props : noise reduction
Since 2008, the E-Props team has been carrying out in-depth research into propeller noise and how to minimize it.
=> See description here: PROPELLER NOISE REDUCTION
4 - Why change propeller ?
A few minutes to ask the right questions about this essential equipment.
=> And see some answers here: WHY CHANGE PROPELLER ?
