PropellerSystemsforElectricPropulsion

Axalp Technologies offers complete propeller hub and blade systems customized to your needs, especially for electric propulsion systems. Hub systems are available in fixed, ground-adjustable, and variable-pitch. We can build your blade shape, or we can make custom designs to meet requirements for power, thrust, and noise.

Propeller Blades

Composite blades for UAVs and aircraft

Axalp's propeller blades are produced in closed mold technology. The blades are typically carbon-fiber-reinforced-plastic (CFRP) sandwich construction, including UV coating. Curing temperatures at 120 C° ensure a safe operation considering hot and wet conditions. Nickel-plated or stainless steel leading edges are available for blade protection.

​Axalp's lightweight blades, combined with our high-performance hub designs can yield some of the best system weights currently available for electric propulsion.

High Performance

Optimized Design

Axalp engineered propeller or rotor blades are fully optimized with respect to aerodynamics, acoustics and structures. With a suite of digital tools we turn around highly optimized aerodynamic surfaces that boast:

  • Excellent thrust properties (high figure of merit)

  • Light-weight, high stiffness

  • Low noise signature

Swiss Quality, Light Weight

Blade Technology

Axalp blades feature an excellent stiffness-to-weight ratio. This is achieved by leveraging the anisotropic properties of carbon fibers by carefully tailoring each ply of the laminate, making sure every gram of material is well invested.

For newly-developed blades, validation can be conducted through:

  • Thrust testing

  • Static structural testing

  • Modal testing

  • Bird strike testing

Ground-Adjustable Hubs

Propeller Hubs

Axalp's ground-adjustable hubs are customized to accommodate between 2 to 9 blades. Interchangeable pitch-blocks offer a quick and maintenance friendly method to set the pitch to any angle you need. 

Blade pitch angles are adjusted by loosening the bolts without disassembling the system. This allows the trunnion-pin extending from the blade root to engage with the pitch-block and set the angle. 

This system allows quick and maintenance friendly pitch adjustability, ensures angles consistency and precision among blades.

Variable-Pitch Systems

Variable pitch for max performance

The constant speed systems allow in-flight pitch adjustment, ensuring maximum power transfer from the motor to the airflow. Axalp's constant speed system is fully electric.

System Features

  • Suitable for propeller diameters of 0.7-2.3 m

  • Wide angle range of up to 45 degree pitch variation

  • Features safety release system with automatic feathering of blades

  • System can accommodate 2 to 7 blades

  • Compact and light hub as low as 2.25 kg

  • Combined system weight less than 14 kg for a 5-blade variable-pitch system of 2.2 m diameter

  • Combined with hollow shaft electric motor

Variable-Pitch Hub Mechanisms

Smaller Propellers

The constant speed system allows in-flight pitch control for smaller diameter propellers. The blade roots are fitted with roller bearings and housed within the split shell hub. The mechanism is sized to react centrifugal, aerodynamic and actuation loads. An offset propeller trunnion engages with all five blades simultaneously. The axial position is controlled via an actuation pushrod through a hollow motor shaft.

A safety mechanism handles actuator failure by disconnecting the pushrod from the actuator. The internal spring will ensure that all blades move to a feathered or climb position (depending on preference).

Variable-Pitch Hub Mechanism

Larger Propellers

The variable-pitch hub for larger diameter propellers uses an innovative blade bearing design which enables replacing a blade without disassembling the entire system. The hub's overall bearing solution minimizes friction and ensures low vibration operation. Every component is dimensioned to perfectly match mission needs and thus minimize weight.

The pitch range can be modified to match given requirements and the behavior in actuator failure cases can be matched to aircraft requirements.

One-Stop-Shop

Full Service Engineering & Fabrication

Axalp acts as one-stop-shop and handles definition, development, fabrication, and testing of full propeller systems.

We work closely with our clients to understand the requirements. Depending on the situation, we can provide existing solutions, or we customize solutions to your needs.

Our customers value the interaction throught the process, resulting in high-quality products ready for integration.

Variable-pitch propeller testing

This video shows some exclusive views of recent testing of our Axalp variable-pitch propeller system.