Stall Speed in a Turn Calculator (Load Factor, Bank Angle & Maneuvering Speed at Weight)
See how stall speed rises in a banked turn: load factor from bank angle, accelerated stall speed as Vs × √n, the stall speed at your actual weight, the reduced maneuvering speed VA below gross weight, and the bank angle at which your approach speed leaves no margin.
How it works
load factor n = 1 ÷ cos(bank) in a level coordinated turn · accelerated stall = Vs × √n · stall and maneuvering speeds at weight: V × √(actual weight ÷ gross weight) · bank at which a speed V stalls = arccos((Vs_weight ÷ V)²)
A wing stalls at an angle of attack, not a speed. In a level turn it has to carry more than the aeroplane's weight — the load factor, 1 ÷ cos(bank) — so it reaches that critical angle at a higher airspeed, the published stall speed times the square root of the load factor. At 30° that is only 7% more; at 60° it is 41%. Weight works the same way in the other direction: a lighter aeroplane stalls slower, and its maneuvering speed (below which full control deflection cannot exceed the load limit) is lower too. The calculator gives these numbers and the margin between the speed you fly and the stall you are flirting with.
Worked example
A trainer with a 48 KIAS clean stall at 2,550 lb, flying at 2,200 lb, stalls wings-level at about 45 KIAS. In a 45° bank (1.41 g) that rises 19% to about 53 KIAS, so a 65 KIAS turn has about a 12 kt (23%) margin, and the wing would stall at about 62° of bank at that speed. Maneuvering speed at this weight falls from 105 to about 98 KIAS.
Frequently asked questions
How much does stall speed increase in a turn?
By the square root of the load factor: 30° bank +7%, 45° +19%, 60° +41%, 70° +71%. A trainer that stalls at 50 kt level stalls near 71 kt in a 60° level turn.
Why is maneuvering speed lower at light weight?
VA is the speed at which the wing stalls before exceeding the design load factor. A lighter aeroplane needs less lift to hit the same g, so it reaches that load at a lower speed: VA scales with √(weight ÷ gross). In turbulence, fly at or below the weight-adjusted VA.
Why are steep turns near the ground dangerous?
Stall speed rises, the aeroplane is often slow and low (base to final), and pilots tend to skid with rudder to tighten the turn — which stalls the inner wing first and can enter a spin with no altitude to recover. Keep pattern turns at or below 30° of bank and coordinated.
Related calculators
For training, planning and education only. The aircraft's approved flight manual (POH/AFM), current charts, NOTAMs, weather and regulations govern every real flight. Verify with your instructor and official sources.