In instrument flying, most turns are flown at standard rate: 3 degrees per second, so a full 360° turn takes exactly 2 minutes. What changes with speed is the bank angle needed to hold that rate, and the size of the circle you fly. Both matter for holding patterns, procedure turns and staying inside protected airspace. Work out bank angle, radius and load factor for any speed with the Turn Rate and Radius Calculator.
Rate one, rate two, rate half
- Rate 1 (standard rate): 3°/s, 360° in 2 minutes. Marked on the turn coordinator.
- Rate 2: 6°/s, 360° in 1 minute. Used by some light aircraft in certain manoeuvres.
- Rate ½: 1.5°/s, 360° in 4 minutes. Faster aircraft are often limited to this because a full rate-one turn would need too much bank.
Most procedures limit the bank to about 25° to 30°. If standard rate needs more than that, fly the bank limit and accept a slower turn.
Bank angle for a standard-rate turn
The exact relationship is tan(bank) = turn rate × true airspeed ÷ g, with rate in radians per second, TAS in metres per second and g = 9.81 m/s². Pilots use a rule of thumb instead:
Bank angle ≈ TAS ÷ 10 + 7
The table compares the rule of thumb with the exact value.
| TAS | Exact bank | Rule of thumb | Turn radius | Load factor |
|---|---|---|---|---|
| 90 kt | 13.9° | 16° | 0.48 NM | 1.03 g |
| 120 kt | 18.2° | 19° | 0.64 NM | 1.05 g |
| 150 kt | 22.4° | 22° | 0.80 NM | 1.08 g |
| 180 kt | 26.3° | 25° | 0.95 NM | 1.12 g |
| 210 kt | 30.0° | 28° | 1.11 NM | 1.15 g |
| 250 kt | 34.5° | 32° | 1.33 NM | 1.21 g |
| 300 kt | 39.5° | 37° | 1.59 NM | 1.30 g |
The rule of thumb is close for typical training speeds of 100 to 160 kt. At higher speeds it understates the bank, and beyond about 210 kt standard rate already needs more than 30°.
Turn radius
At standard rate the radius depends only on speed: radius (NM) ≈ TAS ÷ 188, close to the handy approximation TAS ÷ 200. Doubling the speed doubles the radius.
At a fixed bank angle, the radius grows with the square of speed: radius = V² ÷ (g × tan bank).
| TAS | Radius at 25° bank | Radius at 30° bank |
|---|---|---|
| 100 kt | 0.31 NM | 0.25 NM |
| 150 kt | 0.70 NM | 0.57 NM |
| 200 kt | 1.25 NM | 1.01 NM |
| 250 kt | 1.95 NM | 1.58 NM |
| 300 kt | 2.81 NM | 2.27 NM |
This is why holding speed limits exist. A hold flown much faster than the published maximum needs a far wider turn, which can take the aircraft outside the airspace the procedure designer protected.
Worked example
A light twin flies a holding pattern at 150 kt TAS.
- Rule-of-thumb bank: 150 ÷ 10 + 7 = 22°. The exact value is 22.4°.
- Radius: 150 ÷ 188 ≈ 0.8 NM, so each 180° end of the hold is about 1.6 NM wide.
- Time for the 180° turn: 180 ÷ 3 = 60 seconds.
- Load factor: 1 ÷ cos 22.4° = 1.08 g. The stall speed rises by the square root of that, about 4%.
Load factor and stall speed
In a level turn the wing must support more than the aircraft’s weight. Load factor is 1 ÷ cos(bank). At 30° it is 1.15 g, at 45° it is 1.41 g and at 60° it is 2.0 g. Stall speed increases with the square root of load factor: about 7% at 30°, 19% at 45° and 41% at 60°. Standard-rate turns at normal speeds stay well inside these limits, but steep turns near the ground at low speed do not.
Common mistakes
- Using indicated airspeed. Bank angle and radius depend on true airspeed. At altitude, TAS is well above IAS.
- Applying the rule of thumb at jet speeds. It underestimates bank above about 180 kt.
- Ignoring wind. These radii are relative to the air mass. Over the ground, a strong wind stretches the turn on the downwind side.
- Chasing the rate at high speed. If standard rate needs more bank than allowed, use the bank limit instead.
FAQ
Why is a standard-rate turn 3° per second?
It gives a predictable 2-minute circle that is gentle enough for instrument flying in typical light and turboprop aircraft, and it makes timed turns easy to fly without a heading reference.
Does altitude change the bank angle needed?
Only through true airspeed. At the same IAS, TAS is higher at altitude, so standard rate needs more bank and gives a wider circle.
Is turn radius the same in a climb?
Very nearly, for the climb angles of normal flight. The level-turn figures are accurate enough for planning.
Sources and further reading
FAA Instrument Flying Handbook (FAA-H-8083-15) and Airplane Flying Handbook (FAA-H-8083-3) on rate of turn, bank angle and load factor. For holding speeds and bank limits, use the current AIM, ICAO PANS-OPS and your State’s AIP.
Last reviewed: November 2026.