Taxiway Turning Radius Calculation for Airport Design

The calculation of the turning radius for an airport taxiway is a crucial aspect of airport engineering design, ensuring the safe and efficient movement of aircraft, especially large subsonic jet planes. The turning radius depends primarily on the design speed of the aircraft during turning maneuvers and the friction coefficient between the aircraft's tires and the pavement surface.

Given Parameters for Turning Radius

• Design speed of turning (\(V\)): \(60 \text{ kmph}\)
• Friction coefficient between tyre and pavement surface (\(f\)): \(0.15\)

Understanding Turning Radius Formula

For calculating the minimum turning radius (\(R\)) of a vehicle or aircraft on a horizontal curve, the centrifugal force is balanced by the frictional force. The general formula relating speed, friction, and radius is given by:

\(R = \frac{V^2}{C \cdot f}\)

Where:

• \(R\) is the turning radius in meters.
• \(V\) is the design speed in kilometers per hour (kmph).
• \(f\) is the friction coefficient.
• \(C\) is a constant that incorporates the acceleration due to gravity and unit conversions, ensuring the result is in meters when speed is in kmph. For airport taxiway design calculations, a commonly used constant that yields results consistent with practical design standards is \(C = 125\).

Step-by-Step Calculation of Turning Radius

Let us substitute the given values into the formula to find the turning radius:

1. Substitute the values into the formula:

   \(R = \frac{(60)^2}{125 \times 0.15}\)

2. Calculate the square of the design speed:

   \(V^2 = (60)^2 = 3600 \text{ kmph}^2\)

3. Calculate the denominator:

   \(125 \times 0.15 = 18.75\)

4. Perform the division to find the turning radius:

   \(R = \frac{3600}{18.75}\)

   \(R = 192 \text{ m}\)

Final Turning Radius for Taxiway

Based on the design speed of \(60 \text{ kmph}\) and a friction coefficient of \(0.15\), the calculated turning radius for the taxiway serving large subsonic jet planes is \(192 \text{ m}\). This radius ensures safe and comfortable turning maneuvers for the aircraft on the ground.