Condor Glide Polar and MacCready Speed-to-Fly: Thermal Hop Lab

What is a Glide Polar?

A glide polar is a graphical representation of an aircraft’s performance, specifically how far it can travel horizontally for each unit of altitude lost during gliding. For Andean condors, this curve helps us understand their efficiency in using thermals to gain height and cross long distances.

The glide polar includes different lines representing various flight conditions such as the best lift-to-drag ratio (L/D max) and the minimum sink rate.

The MacCready Speed-to-Fly Rule

The MacCready speed-to-fly rule is a strategy used by gliders to determine the optimal speed for crossing thermal regions. It balances the time spent circling in thermals with the distance covered during glide phases.

By adjusting their speed, condors can maximize their efficiency and cover more ground.

Thermal Centring

Thermal centring refers to a bird’s ability to locate and center itself over a thermal updraft. This skill is crucial for Andean condors as it allows them to gain maximum altitude quickly.

By circling within a thermal, condors can extract the most energy from the rising air currents.

Glide Polar and MacCready in Practice

In practice, an Andean condor would use its glide polar to determine its best L/D ratio for gliding between thermals. The MacCready speed-to-fly rule then guides it on how fast to fly to maximize its distance covered.

By combining these strategies, the condor can efficiently cross long distances with minimal energy expenditure.

Frequently asked questions

Try it live

Everything above runs in your browser — open Condor Glide Polar and MacCready Speed-to-Fly: Thermal Hop Lab and change the parameters while it is running. Nothing is installed, nothing is uploaded, the whole model lives in one tab.