For beginners, installing propellers on FPV drone motors might seem like a trivial step, but it is a critical process that determines whether your FPV drone can fly smoothly and safely.The rotation direction of the propellers is directly linked to the motor's output.If they are installed incorrectly,not only will the drone fail to generate effective lift,but it could also flip over and crash instantly upon takeoff.Even if the propellers are mounted in the correct direction,if they are not securely fastened,they could come loose and fly off during high-speed rotation,causing equipment damage or even personal injury.
Mastering the correct method of attaching props to FPV motors not only makes your FPV drone fly more stably and efficiently but also significantly reduces the risk of accidents.This guide will walk you through the entire process with illustrations—from confirming motor direction and matching propeller types to installation,securing,and pre-flight safety checks—to help you safely take your first step into FPV flying.
Ⅰ.What are the layouts of FPV motors?
Before installing propellers,you must first familiarize yourself with your FPV motor layout and their rotation directions（For more basic knowledge, refer to the FPV Motor Guide）.The orientation of the propellers corresponds strictly to the motor's direction of spin.Without understanding the motor layout,you can easily install a prop in the wrong place or facing the wrong way,preventing the drone from taking off correctly.
1. Quadcopter Motor Numbering and Layout
The vast majority of FPV quadcopters use an"X"layout.The motors are typically numbered as shown in the diagram below(using the default layout for common flight controllers like Betaflight):
Motor 1:Rear Right;Motor 2:Front Right;Motor 3:Rear Left;Motor 4:Front Left.
The flight controller(FC)assigns control signals according to this numbering,so you must ensure your propeller installation matches the motor numbering.
2. "Props In"vs."Props Out"Layouts
There are two common propeller rotation layouts for FPV drones:
Props In:
The front propellers push air inward,and the rear propellers push air inward.This means the front-right and rear-left motors spin counter-clockwise(CCW),while the front-left and rear-right motors spin clockwise(CW).Most open-source flight controllers,like Betaflight,default to"Props In."However,some BNF(Bind-and-Fly)models may come pre-configured for"Props Out."
Props Out:The front propellers push air outward,and the rear propellers push air outward.This means the front-right and rear-left motors spin clockwise(CW),while the front-left and rear-right motors spin counter-clockwise(CCW)."
Props Out"tends to throw airflow and debris away from the FPV camera,which can be better for keeping grass and water droplets off the lens.On micro-drones and Whoops,it can also help reduce turbulence(prop wash)in some scenarios.However,it is also more likely to throw debris toward the frame and flight controller stack.
Regardless of the layout used,the four motors must have alternating rotation:any two adjacent motors must spin in opposite directions,while any two diagonal motors spin in the same direction.This creates a stable torque balance.
3. The Difference Between Clockwise(CW)and Counter-Clockwise(CCW)Rotation
Clockwise(CW)Rotation:When viewing the motor from above the drone,the propeller spins in the same direction as the hands of a clock.These motors are paired with right-hand(standard)propellers.
Counter-Clockwise(CCW)Rotation:When viewing the motor from above,the propeller spins in the opposite direction of a clock's hands.These motors are paired with left-hand(reverse)propellers.
Correctly identifying the rotation direction of each motor is the essential first step to selecting and installing the corresponding propellers.
Ⅱ.Choose the Right Props for Each Motor
Once you understand your FPV motor layout and rotation directions,the next step is to select the matching propeller for each motor.The orientation of the propeller blades must correspond to the motor's direction of spin;otherwise,it will not generate thrust and will cause the drone to flip or fail to lift off.
1. Identifying Propeller Blade Direction
FPV drones use two types of propellers:
CW Prop(Clockwise):
Generates downward thrust when spinning clockwise.When viewed from above,the high edge of the blade is on the right,and the low edge is on the left.The leading edge is higher in the direction of rotation.
CCW Prop(Counter-Clockwise):
Generates downward thrust when spinning counter-clockwise.When viewed from above,the high edge of the blade is on the left,and the low edge is on the right.The leading edge is higher in the direction of rotation.
You can quickly determine a prop's direction by gently running your finger along the blade's edge:you will feel it get thicker as you move from the low side to the high side.
2. How to Match Motor Rotation with Propeller Direction?
Clockwise(CW)Motor,Install a CW/Right-hand Prop(high edge on the right,with the clockwise leading edge being higher).
Counter-Clockwise(CCW)Motor,Install a CCW/Left-hand Prop(high edge on the left,with the counter-clockwise leading edge being higher).
Ensure the four propellers are installed in an alternating pattern:
Diagonal motors have the same rotation direction and use the same type of propeller.
Adjacent motors must use propellers of the opposite direction.
For example:
Props In Layout,Motor 1(CW,CW Prop),Motor 2(CCW,CCW Prop),Motor 3(CCW,CCW Prop),Motor 4(CW,CW Prop).
Props Out Layout,Motor 1(CCW,CCW Prop),Motor 2(CW,CW Prop),Motor 3(CW,CW Prop),Motor 4(CCW,CCW Prop).
3. Understanding Common Markings
When purchasing or unpacking propellers,you will often find directional markings,such as:
"R"or"CW"→Indicates a Clockwise propeller(Right-hand).
"CCW"→Indicates a Counter-Clockwise propeller.
Note:
Markings are not entirely consistent across brands."R"or"CW"commonly indicates a clockwise prop.Some brands might only mark one type(e.g.,with an"R")and leave the other unmarked or marked"CCW."Before installation,always double-check by examining the blade's high edge and direction of rotation.
Ⅲ.Step-by-Step:How to Attach Props to FPV Motors?
After confirming the rotation direction of your motors and the corresponding propeller for each,you can begin the installation.This process may seem simple,but it directly impacts the drone's flight performance and safety.Following these steps correctly will help prevent common issues like incorrect installation,loosening,or collisions,ensuring a smooth and reliable first flight.
1. Prepare Necessary Tools and Materials
1.1 Prop nut wrench or an 8 mm socket(common for M5 nuts)
1.2 1.5 mm/2.0 mm hex driver(for center-screw types or prop guards)
1.3 A strip of paper(only for checking motor direction in Betaflight's Motors tab without props;never bring it near spinning propellers)
Optional:
Low-strength thread-locker(only for"center-screw"micro drones;do not apply to M5 prop nuts)
2. Check Motor Rotation Direction
2.1 Connect to Betaflight→Go to the Motors tab→Check the box acknowledging"I understand the risks."
2.2 Gently move the slider for each motor one by one(at a very low throttle).Observe the direction of spin from above the drone:
Clockwise is CW;Counter-clockwise is CCW.
2.3 If a motor's direction does not match your desired layout(Props In/Out),use the Motor Direction wizard in the Motors tab(Betaflight 4.3+)to reverse it.For older versions or unsupported firmware,you must reverse it in BLHeliSuite or by swapping any two of the three motor wires.
3. Assign the Four Propellers by Direction
3.1 Separate your propellers into two groups:CW and CCW.
3.2 Place each propeller next to its corresponding motor:
CW Motor=Install a CW Prop.
CCW Motor=Install a CCW Prop.
Tip:
When looking down at the propeller,the high edge should lead in the direction of rotation.
4. Mount the Propeller onto the Motor Shaft
4.1 Align the propeller's center hole with the motor shaft and press it down vertically.
4.2 Ensure the prop hub sits flush against the motor's non-slip surface or locating points,with no gaps or misalignment.
4.3 Gently wiggle it to confirm it does not"slip"on the shaft.
5. Secure the Propeller with a Nut
5.1 Thread the M5 prop nut onto the motor shaft.Hand-tighten it first until it presses against the prop hub.
5.2 Use a wrench to tighten it another 1/8 to 1/4 of a turn.The goal is to be"snug,but not overtightened."
Thread Direction:
Most modern motors use M5 right-hand threads, so standard self-locking nuts can be used.
A few older models may use left-hand (CW/CCW) threads on some motors — always follow the markings on the motor or the manufacturer’s documentation to avoid mixing up the directions.
Note:Do not apply thread-locker to M5 prop nuts.They are difficult to remove after high-speed rotation,and the nyloc design makes glue unnecessary.
6. T-mount(Two-Screw)/Press-fit Mounting
6.1 2–3"T-mount(Two-Hole):Use two M2×4–6 mm screws to fasten the prop through the two holes in the hub into the top of the motor.Tighten them evenly in a diagonal pattern.No thread-locker is needed.
6.2 65–75 mm Whoop(Press-fit):Press the prop hub vertically onto the 1.0/1.5 mm motor shaft.Ensure it is fully seated and not loose.If it is loose,replace the propeller or shaft adapter.
Note:
A very small number of models use a single center screw;please refer to the manufacturer's instructions
7. Perform a Rotational Check for Stability
Gently spin each propeller by hand for a full rotation：
It should spin smoothly with no wobble or"vertical jumping.
It should not hit the frame arms,wires,or prop guards.
If you feel any rubbing or contact,immediately remove the propeller and reseat it or adjust wire routing.
8. Power-On Test for Airflow Direction
MANDATORY SAFETY RULE:
Always test without propellers first.Use the Motors tab to confirm motor directions before installing props.
If a props-on test is absolutely necessary:
stay far away from people,wear safety goggles,and hold the frame down firmly.Only use very brief,low-throttle pulses.Never use a strip of paper or your hands to check airflow near a spinning propeller.
Props In:Looking from above,the front prop tips should"pull"air inward.
Props Out:Looking from above,the front prop tips should"push"air outward.
With any layout,all four correctly installed propellers should be blowing air downwards.
9. Final Installation Check
With the power disconnected,gently push the outer edge of each prop in its intended direction of spin to confirm the"high edge"is leading.Never touch the propellers when the drone is powered on or spinning.
The two diagonal propellers should be the same type;adjacent ones should be opposites.The prop hub should be flush with the motor top,and the nuts/screws should be tight.
Ⅳ.Common Mistakes to Avoid
Beginners often make simple mistakes when installing propellers.At best,these errors will prevent the drone from taking off.At worst,they can cause the drone to flip and crash on launch or result in a dangerous prop ejection.Understanding and avoiding these common issues is key to ensuring flight safety.
1. Props Installed Backwards or in the Wrong Position
Symptoms:The drone won't lift off,flips over instantly on takeoff,or hovers poorly even at high throttle.
Cause:The propeller direction does not match the motor's rotation,failing to generate effective lift.
Prevention:Before installing,confirm the direction of each prop(diagonal same,adjacent opposite).Use a strip of paper to check motor direction only during a props-off test.When props are on,never get close to check airflow;only perform a visual check from a distance to confirm the Props In/Out pattern.
2. Incorrect Motor Direction
Symptoms:The propellers are installed in the correct order,but the drone still flips or has control issues on takeoff.
Cause:The motor rotation direction does not match the flight controller's settings,causing the FC to apply incorrect stabilization.
Prevention:First,check motor directions without props in the Betaflight"Motors"tab.If they are incorrect,reverse them in the software.
3. Nut or Screws Not Tightened
Symptoms:Severe vibrations during flight,or even a prop ejection mid-air,leading to a crash.
Cause:The prop nut or center screws were not tightened securely,and the propeller came loose at high RPMs.
Prevention:Manually check that each prop is secure and has no play before every flight.For center-screw models,you can use a small amount of low-strength thread-locker.
4. Mixing Different Propeller Models or Sizes
Symptoms:The drone is unstable,drifts to one side,or the flight controller struggles to correct its attitude.
Cause:Propellers of different sizes,weights,or pitches have different aerodynamic properties,creating an asymmetrical output that the FC cannot balance.
Prevention:All four propellers should be of the exact same model,size,and weight.If one is damaged,it should be replaced as a pair to maintain balance;avoid replacing just a single prop.
5. Failing to Check for Rotation and Clearance After Installation
Symptoms:A metallic grinding sound after takeoff,prop-strikes on wires,or severe vibrations.
Cause:The propeller was not installed correctly(hub not flush)or is hitting nearby components.
Prevention:After installation,spin each prop by hand to check for smooth rotation,ensuring there is no wobble,rubbing,or unusual noise.
Ⅴ.Conclusion
Correctly installing propellers on FPV drone motors is a fundamental skill every new FPV pilot must master.While it may seem like a few simple steps,this process is directly related to your drone's flight efficiency,stability,and safety.From confirming motor direction and identifying propeller orientation to precise installation,securing,and checking airflow,every step requires care and attention to detail.There are no shortcuts.
In practice,developing good installation and inspection habits will not only prevent common accidents like flips and prop ejections but will also extend the life of your equipment.This allows you to focus more on the fun of flying and improving your skills.As long as you follow the steps outlined in this guide,your drone will lift off smoothly on its first flight and soar safely through the skies.