Glide Distance Calculator

Work out glide distance instantly with clear inputs, formula shown and shareable results.

About Glide Distance Calculator

Still-air glide distance is height multiplied by the glide ratio, converted to nautical miles at 6076.12 ft per nautical mile. Wind then changes the distance over the ground: the glide takes the same time either way, so a headwind simply reduces ground speed for that time.

Formula

Glide distance

Still air = height x L/D; over the ground = (still air / glide TAS) x (glide TAS - headwind)

Worked example

With the default values below, Glide Distance Calculator returns Glide distance available of 6.35. Change any input above and every figure here is recalculated in your browser.

Inputs used

Height above the landing surface: 5,000 ft
Glide ratio (L/D): 9 :1
Headwind component: 10 kt
Best glide speed: 70 kt

Results

Glide distance available: 6.35 nm
Still-air glide distance: 7.41 nm
Time to descend: 6.35 min
Average sink rate: 788 ft/min

Step by step

1Values used
2Glide distance
3Glide distance available= 6.35 nm
4Still-air glide distance= 7.41 nm
5Time to descend= 6.35 min
6Average sink rate= 788 ft/min

Assumptions and limits

The result is derived only from the 4 inputs listed above. Anything not among them is not part of the calculation.
In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
Aviation results are planning estimates only. Always verify take-off, landing, fuel, weight and balance figures against the certified Aircraft Flight Manual, current performance charts and applicable aviation regulations before flight.

How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.

Aviation results are planning estimates only. Always verify take-off, landing, fuel, weight and balance figures against the certified Aircraft Flight Manual, current performance charts and applicable aviation regulations before flight.

Frequently Asked Questions

Does a headwind change the best glide speed?

In practice pilots add roughly half the headwind to best glide speed to maximise distance over the ground, at the cost of a little extra sink.

Should I glide at max L/D always?

For maximum distance yes. For maximum time airborne (to work a problem or make a call) fly minimum sink speed, which is slower.