Rate 1 Turn Calculator

Rate 1 Turn Calculator

Calculate Standard Rate Turn Bank Angle and Radius

Turn Performance Results

Required Bank Angle
Turn Radius (NM)
Turn Diameter (NM)
Time for 360° Turn

Understanding the Rate 1 Turn

A Rate 1 Turn, also known as a Standard Rate Turn in aviation, is defined as a turn where the aircraft changes heading at a rate of 3 degrees per second. This is a critical maneuver in Instrument Flight Rules (IFR) operations, allowing pilots to make predictable, timed turns regardless of their speed.

The Standard Rate Formula

To achieve a Rate 1 turn, the required bank angle changes based on the aircraft's True Airspeed (TAS). A common rule of thumb used by pilots is:

Bank Angle = (TAS / 10) + 7

For example, if you are flying at 100 knots, the calculation would be (100 / 10) + 7 = 17 degrees of bank.

Key Turn Metrics

  • Duration: At 3 degrees per second, a complete 360-degree circle always takes exactly 2 minutes (120 seconds). A 180-degree turn takes 1 minute.
  • Radius: Unlike the time, the radius of the turn increases as speed increases. Faster aircraft require significantly more airspace to complete a Standard Rate Turn.
  • IFR Significance: Holding patterns and procedure turns are typically calculated based on the Rate 1 standard to ensure obstacle clearance and traffic separation.

Standard Rate Turn Table

TAS (kts) Bank Angle (°) Radius (NM)
80 15° 0.42
120 19° 0.64
150 22° 0.80
200 27° 1.06
function calculateStandardTurn() { var tas = parseFloat(document.getElementById('tasKnots').value); if (isNaN(tas) || tas <= 0) { alert("Please enter a valid True Airspeed."); return; } // Standard Rate Turn Bank Angle Rule of Thumb: (TAS/10) + 7 // Precise Formula: atan( (TAS_fps * Rate_rad_sec) / g ) // TAS in knots to feet per second: 1 knot = 1.68781 fps var tasFps = tas * 1.68781; var rateRadSec = (3 * Math.PI) / 180; var g = 32.174; var bankAngleRad = Math.atan((tasFps * rateRadSec) / g); var bankAngleDeg = bankAngleRad * (180 / Math.PI); // Turn Radius in feet: R = V / omega var radiusFeet = tasFps / rateRadSec; // Radius in Nautical Miles: 1 NM = 6076.12 feet var radiusNM = radiusFeet / 6076.12; var diameterNM = radiusNM * 2; var timeFor360 = 360 / 3; // Always 120s for Rate 1 // Display results document.getElementById('bankAngleResult').innerHTML = bankAngleDeg.toFixed(1) + "°"; document.getElementById('radiusResult').innerHTML = radiusNM.toFixed(2) + " NM"; document.getElementById('diameterResult').innerHTML = diameterNM.toFixed(2) + " NM"; document.getElementById('timeResult').innerHTML = timeFor360 + " Seconds"; document.getElementById('resultsContainer').style.display = 'block'; }

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