Eights on pylons or pylon eights is a ground reference maneuver where an aircraft is flown in a figure eight pattern around two selected points on the ground (the pylons). However, eights on pylons differs from similar maneuvers such as eights along a road, eights across a road, or eights around pylons in that the objective of eights on pylons is not to maintain a specific altitude and

ground track A ground track or ground trace is the path on the surface of a planet directly below an aircraft's or satellite's trajectory. In the case of satellites, it is also known as a suborbital track, and is the vertical projection of the satellite's or ...

, but rather to fly the airplane so that the pylon remains fixed in place when viewed from the cockpit along a line parallel to the lateral axis of the aircraft. This is only possible when the aircraft is flown at the

pivotal altitude Pivotal altitude is the height for a given ground speed at which the line of sight from the cockpit directly parallel to the lateral axis of the aircraft will remain stationary on an object on the ground. A good rule of thumb for estimating the pi ...

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 change also. However, the pivotal altitude varies only with the ground speed and not with the radius of turn or the angle of bank. So whether the maneuver is flown very close to the pylon with the aircraft banked 60 degrees, or farther from the pylon at 30 degrees bank, the necessary altitude is the same. In the United States, the

Federal Aviation Administration The Federal Aviation Administration (FAA) is the largest transportation agency of the U.S. government and regulates all aspects of civil aviation in the country as well as over surrounding international waters. Its powers include air traffic m ...

requires pilots to demonstrate eights on pylons to obtain a

Commercial Pilot License A commercial pilot licence (CPL) is a type of pilot licence that permits the holder to act as a pilot of an aircraft and be paid for their work. Different licenses are issued for the major aircraft categories: airplanes, airships, balloons, glid ...

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

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