1. What is Maximum Deviation without Filleting?

Definition: This calculator determines the maximum permissible deviation from the centerline that an aircraft can maintain without requiring filleted taxiway curves.

Purpose: It helps airport engineers and planners design taxiways that accommodate aircraft movements safely without excessive pavement widening.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \lambda \) — Maximum deviation without fillets (meters)
• \( T_{Width} \) — Taxiway width (meters)
• \( M \) — Minimum safety margin (meters)
• \( T \) — Track of main undercarriage (meters)

Explanation: The formula calculates the available clearance by subtracting the aircraft track and safety margin from half the taxiway width.

3. Importance of Deviation Calculation

Details: Proper deviation calculation ensures aircraft can navigate taxiways safely without wingtip collisions or going off pavement, while minimizing unnecessary pavement costs.

4. Using the Calculator

Tips: Enter the taxiway width, minimum safety margin (±5%), and main undercarriage track (±5%). All values must be ≥ 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a fillet in taxiway design?
A: A fillet is an asphalt extension at taxiway curves that provides additional clearance for aircraft maneuvering.

Q2: Why is the safety margin expressed as ±5%?
A: The ±5% accounts for variations in pilot technique, aircraft loading, and environmental factors.

Q3: How is undercarriage track determined?
A: It's the distance between the centers of the main gear tires on opposite sides of the aircraft.

Q4: What if the calculated deviation is negative?
A: A negative result indicates the taxiway is too narrow for the specified aircraft without fillets.

Q5: How does this relate to ICAO standards?
A: This calculation helps ensure compliance with ICAO Annex 14 pavement design standards.

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