Glide Ratio & Distance Calculator

Calculate maximum glide distance and best glide speed for emergency planning.

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Typical: C172=9:1, Glider=40:1

Typical Glide Ratios

Aircraft TypeL/D RatioBest Glide
Cessna 1729:165 kts
Piper Cherokee10:176 kts
Cirrus SR2211:188 kts
Light Twin12:1100 kts
Modern Glider40-60:150-60 kts

Understanding Glide Performance

Glide Ratio (L/D)

The glide ratio represents the horizontal distance traveled for each unit of altitude lost. A 9:1 ratio means the aircraft travels 9 feet forward for every 1 foot of descent.

Calculating Glide Distance

Distance (nm) = (Altitude / 6076) x Glide Ratio

From 5,000 ft AGL with 9:1 ratio: (5000/6076) x 9 = 7.4 nm

Wind Effects

Headwind reduces glide distance; tailwind extends it. In strong headwinds, increase speed slightly above best glide. In tailwinds, reduce speed slightly.

Weight Adjustment

Best glide speed increases with weight: V2 = V1 x sqrt(W2/W1). However, the glide ratio remains constant regardless of weight - heavier aircraft just glide faster.