Glide Ratio Calculator

| Added in Physics

What is Glide Ratio and Why Should You Care?

Whether you're a pilot, aviation enthusiast, or just curious about how objects soar through the air, understanding glide ratio is fascinating. In simple terms, glide ratio measures how far a glider or any aircraft can travel horizontally when it descends a certain vertical distance.

Imagine you're flying a paper airplane. The better its glide ratio, the farther it will fly with minimal altitude loss. This is crucial not only for designing efficient aircraft but also for pilots making safe landings in case of engine failure.

How to Calculate Glide Ratio

Calculating glide ratio is straightforward. You simply divide the horizontal distance traveled by the change in altitude:

[\text{Glide Ratio} = \frac{\text{Horizontal Distance}}{\text{Change in Altitude}}]

Where:

  • Horizontal Distance is the distance traveled across the ground.
  • Change in Altitude is the drop in height from starting to landing point.

Use the same units for both measurements (meters with meters, or feet with feet).

Calculation Example

Let's work through an example. A glider travels 12,000 meters horizontally while dropping 800 meters in altitude.

[\text{Glide Ratio} = \frac{12,000}{800} = 15:1]

The glide ratio is 15:1. This means for every meter the glider descends, it travels 15 meters horizontally.

Another Example in Imperial Units

A glider travels 40,000 feet horizontally and loses 2,000 feet in altitude:

[\text{Glide Ratio} = \frac{40,000}{2,000} = 20:1]

This glider has a ratio of 20:1, making it more efficient than the first example.

Quick Tips and Reference

Aircraft Type Typical Glide Ratio
Boeing 747 17:1
Cessna 172 9:1
Competition Glider 40-60:1
Hang Glider 12-17:1
Wingsuit 2.5-3:1

Understanding glide ratios helps you appreciate the art of flight and can be critical knowledge in emergency situations.

Frequently Asked Questions

Glide ratios vary by aircraft. Commercial jets achieve 15-20:1, light aircraft 8-12:1, high-performance gliders 40-60:1, hang gliders 12-17:1, and parachutes around 3:1. Higher ratios mean greater efficiency.

Weight does not affect glide ratio but does affect glide speed. Heavier aircraft must fly faster to maintain the same glide ratio, reaching the ground sooner in time but covering the same horizontal distance.

Fly at best glide speed, minimize drag by retracting gear and flaps, avoid turbulence, seek rising air currents (thermals or ridge lift), and maintain proper trim for coordinated flight.

Glide ratio determines how far an aircraft can travel during engine failure. Pilots use it to calculate whether they can reach a suitable landing site and to plan emergency procedures.