Drone Propeller Pitch Speed Calculator
Calculate the theoretical pitch speed of a drone propeller from its pitch and motor KV rating.
Learn how propeller specs affect maximum airspeed and efficiency.
Propeller Pitch and Drone Speed
A propeller pitch is the theoretical distance the propeller would travel forward in one complete revolution, assuming no slippage — like a screw advancing through a solid material.
Motor RPM from KV rating: RPM = Motor KV × Battery Voltage
Theoretical pitch speed: Pitch Speed (mph) = (Pitch in inches × RPM) / 1,056
Where 1,056 = 63,360 inches per mile ÷ 60 minutes per hour.
Actual airspeed: Actual Speed ≈ Pitch Speed × Propeller Efficiency (typically 60–80%)
Propellers never achieve theoretical pitch speed due to aerodynamic slippage, airframe drag, and the energy lost to air turbulence.
Reading a propeller name (e.g., 5045):
- First two digits = diameter in inches (50 = 5.0 inches)
- Last two digits = pitch in inches (45 = 4.5 inches)
- Some propellers use a third number for blade count: 5045×3 = 3-blade
High pitch vs low pitch:
- High pitch (e.g., 5.1"): More speed at the same RPM, but less thrust at low speed. Better for racing and forward flight.
- Low pitch (e.g., 3.0"): More thrust per watt at low speed, better hover efficiency. Better for photography drones carrying heavy payloads.
Effect of battery voltage: Higher voltage = higher RPM = faster pitch speed. Moving from 4S (14.8V) to 6S (22.2V) increases RPM by 50%, dramatically boosting speed.
KV rating and motor selection:
- Low KV (500–1000): Large propellers, heavy lift, slower speed
- Medium KV (1500–2300): 5-inch racing quads, versatile builds
- High KV (2300+): Tiny whoops, micro quads, very high RPM with small props
Practical limits: Propeller tip speed approaching the speed of sound (~767 mph) creates excessive noise and reduces efficiency sharply. Most efficient drone propellers keep tip speed under 400 mph (0.52 Mach).