Eights on pylons

This is only possible when the aircraft is flown at the pivotal altitude corresponding to the current groundspeed.

If the aircraft is flying in wind, the groundspeed will vary throughout the maneuver and thus the pivotal altitude will also change.

However, the pivotal altitude varies only with the groundspeed and not with the radius of turn or the angle of bank.

In the United States, the Federal Aviation Administration requires pilots to demonstrate eights on pylons to obtain a Commercial Pilot License.

It is also a required teaching and demonstration task during the practical test for a flight instructor's certificate.