Stall Speed Calculator (with Bank Angle and Altitude)
Stall speed is the slowest a wing can fly while still holding the aircraft up. It rises with weight and altitude, and in a banked turn because the wing must carry more load.
Standards:
- NGSS HS-PS2-1
- CCSS HSA-CED.A.4
- AP1 Unit 8
Our alignment; not reviewed by the standards bodies.
The equation
Worked example
- Given
- Aircraft mass (kg): 1100 kg
- Wing area S (m²): 16.2 m²
- Maximum lift coefficient C_L,max: 1.6
- Altitude, standard atmosphere (m, 0–20 000): 0 m
- Bank angle φ (°, 0–84): 30 °
- Answer
- Air density ρ: 1.2250 kg/m³
- Stall speed, wings level (metres per second): 26.1 m/s
- Stall speed, wings level (knots): 50.7 kn
- Load factor n: 1.155
- Stall speed in the turn: 28.0 m/s
- Check
- In a level 60° bank the load factor is 2, so stall speed rises by √2 ≈ 1.414 (FAA Pilot’s Handbook of Aeronautical Knowledge, ch. 5); the build checks this. Sea-level standard density is 1.225 kg/m³.
Assumptions
Generic aircraft, steady flight, U.S. Standard Atmosphere 1976. True airspeed (not indicated). Not for flight planning: always use your aircraft’s flight manual.
Go deeper
Sources
- J. D. Anderson Jr., Introduction to Flight, 8th ed., McGraw-Hill, 2016.
- NOAA, NASA, USAF, U.S. Standard Atmosphere, 1976, U.S. Government Printing Office, 1976.
- NASA Glenn Research Center, Beginner’s Guide to Aeronautics.
- FAA, Pilot’s Handbook of Aeronautical Knowledge (FAA-H-8083-25C).