### Objective To develop knowledge of pivotal altitude and the skill to maneuver the airplane accurately, while dividing attention between the flight path and the selected pylons. ### References - [[Commercial ACS]] Section V.E - [[AFH Ch7]] - [[All Maneuvers Quick Reference]] ### Builds On [[PPL2.5 Ground Reference Maneuvers]] ### Schedule Ground 0.5 hr, Flight 2.0 hr ### Lesson Elements 1. Overview 1. This is the most advanced ground reference maneuver. 2. It requires the pilot to demonstrate ability to plan and select an appropriate location, the skill to fly the maneuver precisely, and the situational awareness to divide attention between the ground references, instruments, traffic, and emergency field location. 3. ![[Eights on Pylons.jpeg]] 2. Eights on pylons relies on [[Pivotal Altitude]] 1. Theory 1. ![[Line of Sight.jpeg]] 2. ![[Bank Angle vs Pivotal Altitude.jpeg]] 3. ![[Altitude Effect on Line of Sight.jpeg]] 2. Approximate calculation: [[GS]]^2/11.3 (for GS in knots)^[For physics nerds, see derivation of pivotal altitude at: https://www.youtube.com/watch?v=oc9mqDadv_M] 3. ![[Groundspeed to Pivotal Altitude]] 4. Site selection 1. There must be a suitable emergency landing field within gliding range. 2. There should be no towers or other hazards to low flight. 3. Choose pylons approximately ~1/2 mile apart (aiming to fly the diagonal between them for 3-5 seconds) 4. Line between pylons should be approximately perpendicular to the wind. 5. The pylons should be at the same elevation. 6. Clearing turns to check for traffic. 5. Initial practice 1. Demonstrate motion of pivot point at excessively high and low altitudes, while circling around a single pylon. 2. Determine PA to use for downwind entry to figure eight pattern, and practice maintaining PA while circling a single pylon. 6. Flying the maneuver 1. Configure and set power for ~100 knots (see [[All Maneuvers Quick Reference]]) 2. Enter from upwind side, flying diagonally crosswind between the pylons, at expected PA for estimated groundspeed. This is the highest altitude part of the maneuver. 3. Roll into turn as reference line aligns with pylon, approx. 30-40° bank. 4. Expect to descend as turn continues and groundspeed decreases. 5. During turn: When pylon gets behind wing, climb. When pylon gets ahead of wing, descend. Use primarily PITCH to maintain the pivot point, and bank as necessary to keep reference line pointing at the pylon 7. Be ready for real or simulated forced landing! 1. Expect, during practice or Commercial checkride, to have a simulated engine failure and forced landing drill! 2. Be prepared to demonstrate flow patterns from memory for Engine Air Restart and Forced Landing emergency procedures. 8. Common Errors 1. Poor selection of site 2. Forgetting clearing turns before maneuver 3. Fixation, failure to divide attention between instruments, traffic, etc. 4. Failure to adjust altitude as necessary to maintain pivot point. 5. Lack of rudder coordination, using rudder to yaw plane to maintain pivot point. 6. Lack of wind drift correction between pylons ### Completion Standards Client must calculate and enter at pivotal altitude, select suitable pylons which allow straight-and-level flight between (3-5 seconds), establish a bank angle <40°, and maintain pylon in line-of-sight without slips/skids. Client must be able to divide attention inside and outside aircraft. ### Required Logbook Phraseology [[FAR 61.127 CPL Flight Reqs]]: - Ground reference maneuvers ### Required Homework - [ ] Memorize pivotal altitude formula ### Recommended Homework - [ ] Chair fly maneuver *Return to [[~ CPL Lesson Plan Outline|Table of Contents]]^*