E-PROPS : Range of Carbon-Titanium Propellers for Direct-Drive Engines
The entire E-Props propeller range for direct-drive engines, from 60 to 270 hp, is currently under development and entering production. Propellers for Lycoming O-360 engines in 74" and 76" diameters are available (the ASCALON range), and many more models will follow soon. This page gathers the range overview and the technical content shared across all these models — for details on each range, see ASCALON & CLARENT (Lycoming/Continental) and VORPALINE & BELISANDRE (Jabiru/Volkswagen).
1 — Range overview4 ranges, engines covered, status of each.
| Range | Rotation | Configuration | Engines | Status |
|---|---|---|---|---|
| ASCALON | CW (clockwise) | Tractor | Lycoming / Continental, 100 to 270 hp | Available since February 2026 |
| CLARENT | CCW (counter-clockwise) | Pusher | Lycoming / Continental, 100 to 270 hp | Under development |
| VORPALINE | CW (clockwise) | Tractor | Jabiru, 80 to 120 hp | Under development |
| BELISANDRE | CCW (counter-clockwise) | Pusher | Volkswagen, 60 to 120 hp | Under development |
2 — Torsional vibration analysis on Lycoming O-360experimental study shared by Ascalon and Clarent.
This report presents an experimental study of torsional vibrations in a direct-drive Lycoming O-360 engine–propeller assembly. Vibratory torque measurements were performed during ground and flight tests on several propeller configurations (aluminium, wood, multi-blade carbon fiber and 3-blade carbon fiber). The results highlight significant differences in torsional resonance behavior, and demonstrate that an optimized propeller design can substantially reduce vibratory coupling. This study applies to the whole direct-drive range for Lycoming/Continental engines (Ascalon and Clarent).
Click here to view the full report:
=> Experimental Torsional Vibration Analysis of Different Propellers on a Lycoming O-360 Engine
3 — Additional note: special direct-drive enginesvibration analysis methodology, LUKY software, ELIAS DAU system.
For special engines, we must perform detailed vibration analyses using our LUKY software.
These analyses require precise input data, including the exact geometry, masses, and moments of inertia of the crankshaft, pistons, and connecting rods, as well as the inertia of all components mounted on the crankshaft. To obtain this information, we have acquired numerous used engines in order to scan and weigh their internal components. When possible, we also collaborate directly with engine manufacturers to access essential technical data.
This work allows us to build accurate vibration models and prepare the corresponding test configurations. Vibration testing is then carried out under real operating conditions, on an installed engine, using an instrumented propeller equipped with our ELIAS DAU data acquisition system. Tests are performed primarily on the ground and, whenever feasible, in flight. When theoretical data is not available, direct testing under operational conditions can also be performed — such campaigns require dedicated operations at our facility (Sisteron airfield, LFNS, Vaumeilh, France).
Based on these measurements, the critical vibration ranges are defined, ensuring that resonance phenomena are avoided and that no harmful vibratory coupling occurs. We can then determine the exact composite layup schedule for each propeller model — or, when necessary, design a new blade — to achieve optimal compatibility with each specific engine configuration. This process takes time, but it is essential: an optimized propeller design significantly reduces vibratory interaction between the propeller and the engine.
