Sep. 01, 2025
By Charles Blouin
Wing Flying supply professional and honest service.
Testing your motors and propellers is the most effective way to evaluate performance and find areas for improvement in your design.
It allows you to make improvements in efficiency, which translates directly into increases in endurance, flight time, payload capacity, and more.
In this article we will cover both the how and the why of motor and propeller testing.
You must first ask yourself, what are your, or your end user’s needs? This question is important as it will help you know which parameters to optimize.
The final choice of power system depends not only on the airframe and payload, but also on your application.
Figure 1: NTM propdrive 35-30 brushless motor and Quantum 13-4 carbon fiber prop.
To fully characterize a motor and determine its efficiency, you need to measure the following parameters.
The parameters listed above are important because they allow you to determine the following key performance indicators:
The output speed is a function of the throttle, in %, and of the load or torque, in Nm. If you want to completely characterize a motor, you will need to test it with multiple input voltages and different loads. The throttle is changed with the controller, and the load is changed with the type and size of propeller.
Further reading: How Brushless Motors Work and How to Test Them
To find propeller efficiency, you will need to measure the following parameters:
These parameters allow you to determine:
Note that the mechanical power is the same for the motor and propeller. That is because all the motor’s mechanical power output goes into the propeller, since it is directly coupled to the motor’s shaft.
The overall efficiency of your system depends on how well your motor and propeller work together. Even with a motor and propeller that are highly efficient on their own, your system can be very inefficient if the two parts don’t match well.
Because these parts have a common link (the shaft), the overall system efficiency is expressed as:
System efficiency (g/watt) = Propeller efficiency (g/watt) * Motor Efficiency
where the system efficiency is in grams per watt of electrical power. Changing the motor, propeller, or even switching to another ESC will all contribute to changing the system efficiency.
Moreover, the efficiency value will only be valid for a specific command input and mechanical load. In practice, this means that you will need to test your motor over a range of command inputs and with various propellers (to vary the mechanical load) in order to get a full efficiency characterization.
In summary, to obtain motor and propeller efficiency you need to simultaneously record voltage, current, torque, thrust, and motor speed. By combining these readings you can extract the electrical and mechanical power, which in turn will give you the efficiency values.
The easiest and most effective way to perform these tests is with a thrust stand, a piece of equipment specifically designed for characterizing motors and propellers.
We used the Series thrust stand (5 kgf/ 2 Nm) to collect the data discussed below, but we also offer thrust stands measuring up to 500 kgf.
Further reading: Why You Should Test Your Drone's Motors and Propellers
Figure 2: The Series thrust stand with brushless motor and propellerIn this article we will only cover static tests (we won’t talk about dynamic tests involving angular acceleration, estimating stall torque, etc…).
Before starting your tests, we recommend to:
A simple but effective test consists of ramping up the throttle in small steps, and recording a sample after every step. Before taking the sample at each step, allow the system to stabilize for a few seconds.
In the video at the beginning of the article, we demonstrate how we manually varied the throttle from 0 to 100% in 10 steps. This procedure could also have been performed using the RCbenchmark software’s automated test feature, which is covered in another tutorial.
Further reading: Automated Propulsion Test Scripts for Your Drone
The results obtained from our manual step test are shown in this CSV file.
You can analyze your output data using any plotting software. Below is an example of a plot we generated obtained using the data from the CSV file linked above.
Here we have compared propeller thrust and mechanical efficiency, to see at what points our propulsion system operates most efficiently.
You could then compare this data with data from other tests using the same protocol but different propellers to find the one that is most efficient with your motor.
For more examples of the types of analysis that you can do with this data, check out our articles on motor and propeller testing.
A drone propeller is a key component that converts rotational energy from a drone's motor into thrust, enabling it to lift, hover, and maneuver. These mechanical parts, typically designed in an airfoil shape, generate lift by creating a pressure difference between their upper and lower surfaces. Propellers are essential for determining a drone's performance, stability, and efficiency, with their design impacting factors such as flight time and maneuverability. In this article, we’ll explore the different types of drone propellers, their main parameters, and the factors to consider when selecting the right propeller for your drone's specific application.
A drone propeller is a mechanical component that converts rotational energy from the drone's motor into thrust, enabling the drone to lift, hover, and maneuver. Typically shaped like an airfoil, propellers achieve this by creating a pressure difference between the upper and lower surfaces of the blades, resulting in airflow that generates lift. Propellers are pivotal in determining a drone's efficiency, stability, and performance. For drones, especially multirotors, achieving balanced thrust across all propellers is essential for maintaining stable flight.
Drone propellers are classified based on material, form, and the number of blades. Each type offers specific benefits and trade-offs that cater to different drone applications.
Plastic Propellers：
●Characteristics: Lightweight, inexpensive, and widely available.
●Advantages: Cost-effective, easy to replace, and suitable for beginner drones.
●Disadvantages: Less durable and prone to deformation under stress or heat.
Carbon Fiber Propellers:
●Characteristics: High-strength and lightweight material.
●Advantages: Greater durability, reduced vibration, and improved aerodynamic performance.
●Disadvantages: Higher cost and more brittle compared to plastic.
Polymer Composite Propellers:
●Characteristics: Made from advanced composite materials.
●Advantages: Balanced performance, combining strength, flexibility, and affordability.
●Disadvantages: Less common and may not be as durable as pure carbon fiber.
Straight Propellers:
●Description: Fixed in shape and configuration.
●Applications: Common in most drones due to their simplicity and reliability.
●Advantages: Efficient thrust generation and easy maintenance.
Folding Propellers:
●Description: Collapsible blades that fold against the drone body during storage or transport.
●Applications: Ideal for portable drones.
●Advantages: Space-saving design, reduced risk of damage during transport.
Polish Propeller:
●Description: A propeller with curved, scimitar-like blades designed to improve aerodynamics by reducing drag and noise.
●Applications: Often used in model aircraft and fixed-wing drones, especially in cases where smooth operation, efficiency, and reduced vibration are desired.
●Advantages: This design improves aerodynamic efficiency by reducing drag and noise while enhancing thrust.
Two-Blade Propellers:
The company is the world’s best drone propeller efficiency test supplier. We are your one-stop shop for all needs. Our staff are highly-specialized and will help you find the product you need.
●Characteristics: Simplest design, offering high efficiency and low drag.
●Applications: Commonly used in lightweight drones.
Three-Blade Propellers:
●Characteristics: Enhanced stability and thrust at the cost of slightly reduced efficiency.
●Applications: Popular for FPV (First-Person View) drones due to better maneuverability.
Four-Blade (or More) Propellers:
●Characteristics: Increased thrust and control at the cost of reduced flight time.
●Applications: Suitable for high-performance or heavy-lifting drones.
Drone propellers are characterized by several key parameters that influence their performance, efficiency, and suitability for different applications. These parameters include:
●Diameter: The diameter determines the amount of air displaced by the propeller. Larger diameters generally produce more thrust but may also increase drag.
●Pitch: This refers to the theoretical distance a propeller would move forward in one complete revolution if there were no resistance. Higher pitch values can increase thrust but also require more power.
●Blade Configuration: The arrangement of blades affects lift and stability. More blades can enhance lift but may require more power to maintain speed.The shape of the blade's cross-section, influencing lift and drag. Rounded, pointed, or swept tips reduce noise and improve efficiency.
●Weight: Heavier propellers require more motor power but can provide greater momentum, while lighter ones improve responsiveness.
The interaction between propellers and thrust/RPM is fundamental to propulsion, as thrust depends on the speed (RPM), size, shape, and pitch of the propeller blades. As RPM increases, the propeller moves more air, generating thrust roughly proportional to the square of RPM, but at the cost of power demand rising with the cube of RPM. Larger propellers and higher pitch generate more thrust but require more torque and power, while efficiency peaks at specific RPM ranges depending on the design. Matching the right propeller to a motor ensures optimal performance, balancing thrust, efficiency, and power consumption for the intended application.
Drones are categorized into Multi-Rotor Drones, VTOL Drones, Fixed-Wing Drones, Fixed-Wing Model Aircraft, and FPV Drones, each designed for specific application scenarios and featuring distinct operational characteristics. Multi-rotor drones excel in hovering, stability, and precise control, making them ideal for photography, inspection, and delivery tasks. VTOL drones combine vertical takeoff and landing capabilities with efficient forward flight, suitable for mapping and surveying. Fixed-wing drones prioritize long-distance and endurance flights, focusing on speed and energy efficiency, while fixed-wing model aircraft are tailored for recreational or competitive flying, balancing speed, agility, or aerobatic performance. FPV drones, optimized for speed and maneuverability, are used in racing and freestyle flying, requiring responsive and durable designs. These differences shape the choice of propellers, motors, and materials, ensuring each type meets its unique functional and environmental demands.
Regardless of the drone type, several universal factors should be considered when selecting propellers:
●Material: The choice between plastic, carbon fiber, or polymer composites affects durability, weight, and performance.
●Motor Compatibility: Ensure that the propeller matches the motor’s KV rating; higher KV motors pair well with lower pitch props, while lower KV motors benefit from higher pitch options.
●Flight Efficiency: Consider how the propeller design will impact overall flight time; lower pitch props tend to be more efficient at lower throttle settings but may not provide enough thrust at higher speeds.
When choosing propellers for different drone applications, it is essential to consider the unique requirements of each use case. These requirements influence the design, size, and performance of the propellers. Below are the key differences to consider:
1. Thrust vs. Speed
Heavy-Lifting or Payload-Carrying (e.g., delivery drones):
●Requirement: High thrust to lift heavy loads.
●Propellers: Larger diameter and lower pitch to maximize lift and efficiency at lower RPMs.
Speed-Centric Applications (e.g., racing drones):
●Requirement: High speed and acceleration.
●Propellers: Smaller diameter with higher pitch for greater forward velocity and rapid RPM changes.
2. Flight Stability vs. Agility
Aerial Photography and Videography:
●Requirement: Smooth, stable flight with minimal vibrations.
●Propellers: Balanced, low-noise propellers with moderate pitch and 2-3 blades for stability.
Freestyle and Racing (FPV Drones):
●Requirement: High agility and precise control for sharp maneuvers.
●Propellers: High-pitch, multi-blade propellers (e.g., 3 or 4 blades) for better grip and responsiveness.
3. Efficiency vs. Performance
Long-Endurance Drones (e.g., surveying, mapping):
●Requirement: Maximizing flight time and range.
●Propellers: Large-diameter, low-pitch, and lightweight materials for optimal efficiency at cruising speeds.
High-Performance Drones (e.g., VTOL or military applications):
●Requirement: Balancing vertical lift and forward flight efficiency.
●Propellers: Mixed designs (e.g., folding forward-flight props or large hovering props).
4. Propeller Noise
Commercial or Urban Applications (e.g., delivery, inspection):
●Requirement: Low noise levels to minimize disturbance.
●Propellers: Noise-reducing designs with optimized tip shapes and lower RPM operation.
Racing or Industrial Drones:
●Requirement: Noise is less critical compared to performance.
●Propellers: Higher-pitch and stiffer materials to prioritize power and control.
5. Durability and Safety
Recreational Drones:
●Requirement: Safety and cost-effectiveness for beginners.
●Propellers: Flexible plastic materials that are less likely to break during crashes.
Industrial or Harsh-Environment Drones:
●Requirement: High durability and reliability.
●Propellers: Stiff carbon fiber materials to withstand stress, wear, and environmental conditions.
Drone propellers play a critical role in flight dynamics, directly influencing performance and efficiency. Whether you're piloting a professional-grade VTOL drone or a nimble FPV racer, selecting the right propeller involves understanding the interplay of material, form, blade count, and parameters like pitch and diameter. By aligning these features with your drone's requirements, you can achieve optimal performance for your specific application. Always remember that testing different configurations can lead to optimal results tailored to your specific needs. Grepow offers UAV batteries and semi-solid state batteries ranging from 4S (14.8V) to 18S (68.4V) with capacities up to 84Ah, designed to support a wide variety of applications and compatible with drones equipped with diverse propellers setups. If you have any questions or needs, please feel free to contact us at .
Related Articles:
An In-Depth Guide to Drone Motors
What is a Drone ESC and Is it Important?
Understanding Drone Payload: A Comprehensive Guide
What Is A Drone Flight Controller?
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