Descent Rate Calculator
Calculate descent rate for approach planning
Inputs
Provide the following 2 values to run the Descent Rate Calculator:
- Ground Speed (knots) [number] (required)
- Descent Angle (°) [number] — default 3
What it calculates
This tool returns:
- Descent Rate (fpm) — primary result
- Feet per NM (ft/nm)
- Gradient (%)
Worked example
For the sample inputs below:
- Ground Speed (knots): 450
- Descent Angle (°): 3
the Descent Rate Calculator produces:
- Descent Rate: 2388 fpm
- Feet per NM: 318 ft/nm
- Gradient: 5.2%
How it works
The result is derived through the following steps:
groundSpeedFpm = groundSpeed * 101.269gradient = tan(descentAngle * PI / 180)descentRate = gradient * groundSpeedFpmfeetPerNm = tan(descentAngle * PI / 180) * 6076
Frequently Asked Questions
What is a descent rate in aviation?
The descent rate is the vertical speed at which an aircraft descends, typically measured in feet per minute. It is crucial for approach planning.
How do I use the Descent Rate Calculator?
Simply input the current altitude, desired altitude, and the distance to the destination. The calculator will provide you with the optimal descent rate.
Why is calculating descent rate important?
Calculating descent rate is important for ensuring a safe and efficient landing approach, helping pilots manage their flight path and fuel use.
Can this tool be used for all types of aircraft?
Yes, the Descent Rate Calculator can be used for various aircraft types, but always consider the specific aircraft’s performance characteristics.
Is the Descent Rate Calculator free to use?
Yes, the Descent Rate Calculator is completely free and accessible to all aviation enthusiasts and professional pilots.