Years ago, every young pilot wannabe had to learn and perform the 180-degree power-off approach and landing to pass the private pilot checkride. It took a bit of practice, but most young pilots mastered the maneuver. Today, this approach and landing are no longer required for meeting either the sport or private pilot requirements. You need only satisfactorily perform this maneuver for the commercial pilot checkride.
The FAA defines the power-off 180
approach and landing as an approach and landing made by gliding with the engine
idling from downwind to a touchdown beyond and within 200 feet of a designated
line or mark on the runway.
Today, this maneuver is all but
forgotten. Personally, I teach the technique to all students because I truly
believe they will be better, safer pilots as an end result. What better way is
there to teach a student pilot to see, feel, interpret, understand, and act on
what the airplane is telling you, as well as how the wind is affecting your
flight path?
Once students have satisfactorily
demonstrated the ability to fly a traditional rectangular traffic pattern, adjust
power correctly, and stabilize the approach to land consistently, it is time to
introduce variables. In preparation for the first solo flight, a good deal of
time is spent on “what if” situations where the simulated loss of engine power
is done at different points within the pattern. Showing good decision-making
skills and being able to safely get the aircraft on the ground at the airport
prepares students for that first solo flight.
Teaching the Power-Off 180 Approach
My first challenge to students when
practicing this maneuver is to have them select a landing spot on the runway,
usually about one-third of the runway length beyond the threshold and numbers.
Then I tell them that on the next time around the traffic pattern, at the point
abeam their preselected spot, to apply carb heat, reduce power to idle, and
adjust their traffic pattern flight path in whatever manner is needed to safely
fly the approach and land on, or just beyond, the point they selected. As an
instructor, this can get quite interesting observing the many inputs and
gyrations, or lack thereof, students attempt to use to fly the approach and
land on the desired spot. I’ve experienced everything from hard skidding turns
with faces smashed against the side window to near vertical dives at the runway
and runway alignment somewhere in the next county. After allowing students to
administer these gyrations for 10-20 seconds, it’s time for executing a
go-around and discussing what we just experienced. At this point, students
usually become quite attentive and ready to observe, listen, and learn, as they
have doubts the maneuver can be done!
The discussion includes best glide
speed, rate of descent, and what tools are available to complete the 180-degree
approach and landing. Isn’t it better to arrive at the approach end of the
runway with excess altitude rather than a shortage? Then why didn’t we
establish the best glide speed from the start to preserve the altitude we had,
assuring ourselves the spot on the runway can be reached? Don’t forget excess
energy (5 mph faster than best glide speed) can significantly add to the float
and landing distance. If we are to land at or less than 200 feet beyond the
targeted touchdown point, we need to dissipate this excess energy just before
reaching our targeted touchdown point.
Determining Rate of Descent
Do we know the approximate rate of
descent for the aircraft we are flying? This often-overlooked fact can play a
vital role in whether a safe approach and landing can be made. If you do not
know the rate of descent of your aircraft, you should climb to a safe altitude,
adjust your power to idle, and then establish the recommended glide speed and
time the descent for one minute. Now you have a base point from which to
operate and make your calculations for the 180-degree power-off approach.
Tools available for controlling the
rate of descent include the slip, S-turns, and the use of flaps (if your
aircraft is so equipped) while flying the final approach leg. Slips can be
varied from flying with the wing just a few degrees down, to adding opposite
rudder inputs to lose small amounts of altitude, to using full aileron and
rudder deflection if significant altitude must be dissipated. S-turns can also
be used, but they are difficult to execute if flying a short, tight pattern.
Flaps are a great tool. However, do not make the mistake of employing full
flaps the instant the power is reduced. Rather, apply a few degrees at a time
to help control your glide. Excess flap usage too soon will cause you to land
short of your desired spot and probably well short of the runway.
If you’re using flaps, don’t
retract them once they’ve been applied as doing so reconfigures the wing at or
below the no-flap stall speed and a stall can occur.
Wind, a Misunderstood Factor
Wind direction and velocity must be
taken into consideration when executing the 180-degree power-off approach. This
is a factor often overlooked or not taught at all in primary training. What is
the wind doing to affect the flight pattern in the traffic pattern and on the
final approach? If we are planning to land on Runway 29 and the wind is 280
degrees at 12 knots, what can we anticipate? What must we do to compensate for
the wind?
We can expect a good tailwind while
on the downwind leg. If we’re practicing this maneuver in a J-3 Cub, the
airspeed will be 70 mph and our groundspeed will approach 85 mph. It’s easy to
forget the push we’re getting and unintentionally extend our downwind leg
beyond the point where the turn should be made onto the base leg. Now
established on base, the wind is pushing us away from the runway unless a crab
angle to the left is initiated, which offsets the sideward push of the
crosswind.
Continuing the 180-degree turn onto
final, it almost feels as if we’ve flown into a wall as the wind is now on our
nose and groundspeed is reduced to about 45 mph. Visually, it appears as if
we’re descending more rapidly than anticipated, even though we’re holding a
steady best glide speed.
After allowing students to
experience this approach and its shortcomings, we’ll execute a go-around. This
time, selecting the same target on the runway, we will make corrections for the
wind influence. After reducing power to idle, the turn to the base leg portion
is initiated almost immediately, including a leftward crab angle preventing the
wind from pushing us away from the runway. I like to make the turn onto the
final approach a bit earlier than some, but I do so using a very shallow bank,
which allows me to keep an open line of sight on my target touchdown spot on
the runway and make bank adjustments as needed to align the aircraft with the
runway centerline.
While maintaining a constant glide
speed, altitude adjustments are made as necessary to reach and touch down on,
or just beyond, the target point. Learning to interpret altitude is an acquired
skill achieved through practice and repetition. I like to have students
establish the best glide speed, then, while looking over the nose, pick a spot
on the runway and glide to it. If the runway appears to be dropping down and
moving toward you, the glide path is too high. If the runway appears to be
moving upward and away from you, the glide path is too low.
I tell students, “Pretend you’re a
lawn dart. If corrective action to make the landing wasn’t made, we would stab
the runway at exactly the point where you are aiming!”
Practicing the 180-degree power-off
approach can be fun and challenging. In the end, when mastered, you’ll be a
much safer pilot as well. Should the day ever occur when you do experience a
power loss and must make an unscheduled landing, you’ll know how to do so
without damage to yourself or your airplane.
Steve Krog, EAA 173799, has been flying for more than four decades and giving tailwheel instruction for nearly as long. In 2006 he launched Cub Air Flight, a flight-training school using tailwheel aircraft for all primary training. For more from Steve, read his monthly column in EAA Sport Aviation Magazine.