E-PROPS ASCALON & CLARENT: Carbon-Titanium Propellers for Direct-Drive Engines

✗  Range of 2- & 3-blade propellers, ground adjustable pitch, Carbon with Titanium leading edge protection
✗  For tractor aircraft, rotation sense clockwise (CW)
✗  Innovative blade profiles

✗  For direct-drive engines Lycoming & Continental from 100 to 270 hp:
- 4 cylinders: up to 210 hp — Continental O-200, O-240, IO-240; Lycoming O-235, O-290, O-320, O-360, IO-360, IO-390
- 6 cylinders: up to 270 hp — Continental C145, O-300, O-360, O-470, IO-470; Lycoming O-540, IO-540

✗  Diameters available: 183 cm / 72 inch, 188 cm / 74 inch, 193 cm / 76 inch (from 140 to 210 cm in the future)
✗  2-blade weight = 6 kg / 3-blade weight = 7 kg
✗  Drilling patterns = 4" (like Rotax 9xx), SAE1, SAE2 AN6, SAE2 AN8
✗  Max RPM = 3,300
✗  Moment of Inertia: 6000 kg.cm² (190 cm diameter models) — same as wooden propellers for these same engines

✗  Unlimited service life / 2,500 hours inspection interval
✗  Propellers in VHR Carbon (Very High Resistance) with Titanium leading edge protection
✗  Very strong: 100% carbon, very high fiber ratio, RTM manufacturing process
✗  No critical cyclic stresses on aluminum components, eliminating the risk of cracking and galvanic corrosion

✗  Currently undergoing certification by EASA (and subsequently by the FAA)

Carbon spinners: diameters from 300 mm to 380 mm. Integrated carbon spacers: lengths from -15 mm to 230 mm, every 5 mm.

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. Onboard the aircraft, the recording unit — nicknamed Bob — houses the control screen, the recorder and the battery. Thousands of measurements are transmitted in real time (Wi-Fi, and 3G for flight campaigns) to this onboard computer and to a cockpit display that lets the pilot refine the flight profile according to the required test parameters.

First ELIAS tests on ASCALON: Clemens' testimonial

First use of ELIAS on an ASCALON propeller: a real success, with the measurement files sent by email immediately after the ground tests. Clemens' aircraft is an aerobatic Pitts S1C, fitted with a Lycoming O-320 A2A engine (FAA Experimental category, United States). Here is his feedback, received after this campaign:

"As discussed here my thoughts about the Ascalon ground tests:"

Positive:

• Communication and support was great.
• Shipment of parts and preparation was very good.
• All parts were easy to handle.
• Installation was easy and intuitive.
• Quality of material and manufacturing is very nice.

Potential for improvement:

• "Elias Software" is nice and easy to use, but finding the right file is not obvious.
• For me, the most complex task was the adjustment of the blade angle. If you move the goniometer just a millimeter on the plane's Y axis (right or left), the measurement of the angle differs a lot. Since the blade angle sometimes changes a little during the tightening of the bolts, a tolerance for the blade angle (e.g. 30.5° +/- 0.1°) would be helpful.
• Maybe some pictures and a detailed description of the angle adjustment process in the manual would be helpful.

"Thanks again for the great support and your help. I am looking forward to the first flight with the Ascalon. I will extract the precise flight test data from the Sensenich for comparison."

— Clemens

Thanks to their ESR effect (Extended Speed Range), ASCALON propellers deliver strong thrust at all engine RPM.

Initial noise measurements show promising results: a 6 dB(A) reduction was measured comparing ASCALON to a standard propeller on an aircraft fitted with an exhaust muffler.

The ASCALON range complies with ASTM F2506-26, with a TBO of 2000 hours. Work on EASA CS-P certification for this range is underway: the TC (Type Certificate) application has been submitted to EASA and is currently being reviewed, with 7 engineers from the E-Props design office working on it to move forward as quickly as possible. Once the EASA TC is obtained, E-Props will apply for FAA 14 CFR Part 35 certification. Tests will then also be needed for the STCs (Supplemental Type Certificates) for each aircraft-engine-propeller combination.

See the E-Props certifications page.

February 1st, 2026: the ASCALON range is on the market! The first models, available in 2- and 3-blade versions, are offered for Lycoming O-360 engines: ASCALON 2-blade — €3,500, ASCALON 3-blade — €4,500. Discover them here: ASCALON catalog. Many other models for all configurations will be available soon.

September 2026 update: new models are now available, in addition to the Lycoming O-320 and O-360 models — an ASCALON range for Continental O-200 and Lycoming O-235 engines. The ASCALON 2-blade propeller, 72-inch (183 cm) diameter, has completed its ground-test campaign on a Jodel DR-1050 MV fitted with a Continental O-200, instrumented with our ELIAS data-acquisition system (vibration, blade-root loads, thrust, torque, RPM, pressures, temperatures).

In this video, we take you behind the scenes of one of our most spectacular tests: the bird-strike impact test, performed on an ASCALON propeller blade using our own chicken gun — a very rare capability in the propeller industry!

CLARENT is the pusher (counter-clockwise, CCW) variant of the ASCALON range, for aircraft in pusher configuration — for example aircraft from the RUTAN family (VariEze, LongEze, Cozy...). It shares the same technical foundations as ASCALON: 2- and 3-blade ground-adjustable pitch propellers, carbon with Titanium leading edge protection, innovative blade airfoils, for Lycoming & Continental engines from 100 to 270 hp (same engine range, diameters from 140 to 210 cm, weights of 6 and 7 kg, SAE1 & SAE2 bolt patterns, max RPM 3,300, moment of inertia 6000 kg.cm² at 190 cm diameter — same as wooden propellers for these same engines). Accessories: carbon spinners (300 to 380 mm) and integrated carbon spacers (-15 to 230 mm, every 5 mm).

These propellers, dedicated to Lycoming and Continental engines in pusher configuration, are currently undergoing a specific development by our team: we pay special attention to the design and mechanical strength calculations, ahead of manufacturing dedicated molds and tooling, followed by the essential testing needed to fully validate these new propellers in real operating conditions.