So imagine you are flying along fat, dumb, and happy (or imagine your friend is flying along fat and dumb if you’re insecure) at 10,500′ and all of a sudden your engine quits. You notice an airport just a few miles away and start gliding towards it as you run your emergency checklists. You arrive over top the airport at 4,000′ above field elevation and now need to position yourself in a good place to glide to a landing on that perfectly good runway right below you.
Surprisingly, many pilots will manage to mess this up and glide their airplane somewhere other than 1,000-1,500′ down the runway making a safe and uneventful touchdown. So now during this maneuver you get to practice circling the airport while descending, basically making a large “turn about a point” while descending down to pattern altitude.
You’ll start high enough above the airport to make 3 full 360 degree turns over the airport (probably 4,000-6,000′ agl depending on how much of a “flying brick” you happen to be at the controls of that day). Your instructor can tell you exactly how much altitude to plan to lose power off for every 360 degree lap over the airport.
During the maneuver you want to make an even ground track over a “point” on the ground (the point is usually the center of the runways the examiner has chosen for you). You will vary your bank angle to account for wind drift, while ensuring you do not exceed maneuvering speed or exceed 60 degrees of bank (this maneuver should be done at best glide speed since you are “engine out”).
The examiner will specify a heading for you to roll out on after ending the maneuver (usually you’ll break it off around 1,500′ agl). While it is not common, some examiners may combine this maneuver with the Power Off 180 to get maneuvers done more efficiently during the ride and have you really show them you can land from an engine failure at high altitude and put the airplane right where you want it. Note: Nothing says this maneuver has to be done over top an airport, obviously if you are not doing this over an airport and instead using a defined point on the ground, you will not be expected to roll out of the maneuver and perform the power off 180 landing. (I like to do these over the airport just in case running the engine at idle for the extended period of time causes the plugs to fowl and an actual engine failure (consider “clearing the engine” periodically on your way down)).
The ACS Criteria:
- Clear the area.
- Select an altitude sufficient to continue through a series of at least three 360° turns.
- Establish and maintain a steep spiral, not to exceed 60° angle of bank, to maintain a constant radius about a suitable ground reference point.
- Apply wind drift correction to track a constant radius circle around selected reference point with bank not to exceed 60° at steepest point in turn.
- Divide attention between airplane control and ground track, while maintaining coordinated flight.
- Maintain the specified airspeed, ±10 knots, rolls out toward object or specified heading, ±10°.