EIGHTS ON PYLONS

Updated: 5 days ago

Eights on Pylons Lesson by wifiCFI


Objective

To determine that the applicant exhibits satisfactory knowledge, risk management, and skills associated with eights on pylons.

Knowledge

The applicant demonstrates understanding of: 

Purpose of eights on pylons. 

Aerodynamics associated with the eights on pylons to include coordinated and uncoordinated flight. 

Pivotal altitude and factors that affect it. 

Effect of wind on ground track. 

Phases of the eights on pylons maneuver from entry to recovery.

Risk Management

The applicant demonstrates the ability to identify, assess and mitigate risks, encompassing: 

Failure to divide attention between airplane control and orientation. 

Collision hazards, to include aircraft, terrain, obstacles, and wires. 

Low altitude maneuvering/stall/spin. 

Distractions, loss of situational awareness, and/or improper task management. 

Failure to maintain coordinated flight. 

Failure to manage energy. 

Emergency landing considerations.

Eights on Pylons (AFH C6)

The eights-on-pylons is the most advanced and difficult of the ground reference maneuvers. 

Because of the techniques involved, the eights-on-pylons are unmatched for developing intuitive control of the airplane.

The goal of the eights-on-pylons is to have an imaginary line that extends from the pilot’s eyes to 

the pylon. 

This line must be imagined to always be parallel to the airplane’s lateral axis. 

Along this line, the airplane appears to pivot as it turns around the pylon. 

In other words, if a taut string extended from the airplane to the pylon, the string would remain parallel to lateral axis as the airplane turned around the pylon. 

At no time should the string be at an angle to the lateral axis.

The visual reference line, while not necessarily on the wingtip itself, may be positioned in relation to the wingtip (ahead, behind, above, or below), and differs for each pilot and from each seat in the airplane.

Pivotal Altitude

The altitude that is appropriate for eights-on-pylons is called the “pivotal altitude” and is determined by the airplane’s groundspeed.

An explanation of the pivotal altitude is also essential. 

First, a good rule of thumb for estimating the pivotal altitude is to square the groundspeed, then divide by 15 (if the groundspeed is in miles per hour) or divide by 11.3 (if the groundspeed is in knots), and then add the mean sea level (MSL) altitude of the ground reference. 

The pivotal altitude is the altitude at which, for a given groundspeed, the projection of the visual reference line to the pylon appears to pivot.

The pivotal altitude does not vary with the angle of bank.

Above Pivotal Altitude

At any altitude above that pivotal altitude, the projected reference line appears to move rearward in a circular path in relation to the pylon.

Below Pivotal Altitude

Conversely, when the airplane is below the pivotal altitude, the projected reference line appears to move forward in a circular path.

Pivotal Altitude

The pivotal altitude is critical and changes with variations in groundspeed. 

Since the headings throughout turns continuously vary from downwind to upwind, the groundspeed constantly changes. 

This results in the proper pivotal altitude varying slightly throughout the turn. 

The pilot should adjust for this by climbing or descending, as necessary, to hold the visual reference line on the pylons. 

This change in altitude is dependent on the groundspeed.

Selecting the Pylons

Selecting proper pylon is an important factor of successfully performing eights-on-pylons. 

They should be sufficiently prominent so the pilot can view them when completing the turn around one pylon and heading for the next. 

They should also be adequately spaced to provide time for planning the turns but not spaced so far apart that they cause unnecessary straight-and-level flight between the pylons.

The distance between the pylons should allow for the straight-and-level flight segment to last from 3 to 5 seconds.

The pilot should select two pylons along a line that lies perpendicular to the direction of the wind.

Common Errors

Incorrect use of the rudder.

Failure to adequately clear the area above, below, and on either side of the airplane for safety hazards, initially and throughout the maneuver. 

Poor selection of ground references. 

Failure to establish a constant, level altitude prior to entering the maneuver. 

Failure to maintain adequate altitude control during the maneuver. 

Failure to properly assess wind direction.

Failure to properly execute constant radius turns. 

Failure to manipulate the flight controls in a smooth and continuous manner. 

Failure to establish the appropriate wind correction angles. 

Failure to apply coordinated aileron and rudder pressure, resulting in slips or skids. 

Failure to maintain orientation as the maneuver progresses.

Commercial Pilot ACS Standards

Clear the area. 

Determine the approximate pivotal altitude. 

Select suitable pylons that will permit straight-and-level flight between the pylons. 

Correctly enter the maneuver at the appropriate altitude and airspeed. 

Establish the correct bank angle for the conditions, not to exceed 40°. 

Apply corrections so that the line-of-sight reference line remains on the pylon. 

Divide attention between accurate, coordinated airplane control and outside visual references. 

Maintain pylon position using appropriate pivotal altitude, avoiding slips and skids

FAA Sources Used for This Lesson

Commercial Pilot Airmen Certification Standards

Airplane Flying Handbook (AFH) Chapter 6

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