Private Pilot Flight Training and Instruction
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Teaching Ground Reference
More often than not ground reference is taught as though it
were the end itself and not a tool for use. We are not trying
to teach how to buzz your friend's front yard. The purpose of
ground reference training is to be able to control the aircraft
in coordinated flight while dividing attention between aircraft
control, altitude, and the ground track. The application of ground
reference skills and perceptions enable the pilot to safely maneuver
and fly a selected ground track while landing. The key to landing
is getting the aircraft configured, keeping visual track with
both headings and reference points, while making wind corrections.
Being able to fly an accurate ground track and altitude about
an airport in a strong wind is an essential skill.
Due to wind, where the nose of the airplane points is not,
necessarily, where it goes. When wind velocities permit a demonstration
of how an airplane is moved by the wind can be done by holding
a 360° turn in a 30° bank and noting that you
do not make a circle over the ground but are moved by the wind
into an ellipse. Banks used during ground reference are not all
or nothing. Banks should be smoothly and continuously entered
and removed. Aileron pressure must continuously be both held into
the bank or against the bank any time it leaves 30-degrees. Coordinated
rudder either in anticipation or application is a must. As the
lessons proceed we will devote ever more attention outside the
aircraft. Rectangles require about a 50-50 split. S-turns about
80-20. Eights on pylons for the commercial require near total
outside attention.
When you make a turn that is going to be affected by the wind,
and they all are, you are going to vary your roll rate and bank
angle. How fast and how much takes practice. This practice is
best noted close to the ground.
Since entries are usually with the wind behind you, you must be
quicker into the bank and perhaps with greater angle. Ground track
is determined by ground speed and you have the wind adding to
your airspeed. You must get around further and faster, hence you
begin sooner, react more quickly and bank more. Failure to do
so will bend your path around the turn and require additional
corrections further on.
When you are making your turn into a headwind you will again
vary your roll rate and bank angle. This time you will begin later,
react more slowly, and use less bank angle. Because of the wind
you will be flying with a lower ground speed so everything happens
more slowly.
Ground proximity flying creates problems more psychological
than real. All aircraft controls function the same but the ground
movement gives an impression of speed not available at altitude.
This impression is sometimes a deceptive illusion. One real hazard
is a bird. At ground reference altitudes the possibility of a
bird strike is greatly increased. The pilot should become aware
of the seasonal migratory flight of birds and of their presence.
A bird instinctively reacts to an airplane as a 'hawk'. It will
dive. The pilot's best reaction is to climb in the presence of
birds. A defense is to fly with the landing light on. Birds will
react to the light before reacting to the airplane. There is no
practical need to do any ground reference below 300' and during
duck hunting season 500' should be a minimum. 700' is a good student
minimum. There will be little benefit if ground reference is practiced
at altitudes over 1000'.
I suggest that all ground reference maneuvers be performed
in a C-150 at full cruise. This reduces the potential for an inadvertent
stall. The student must be told of any local obstructions such
as poles or wires. A minimum altitude should be assigned for solo
practice. Simulated emergencies or landings should never be attempted
or practiced by the solo student. However, the student should
be made aware of every potential safe landing space in the practice
area in case of an actual emergency. Simulated emergencies should
be experienced during ground reference training.
The student must learn to look for and find wind direction
and velocity indicators. Waves, smoke, tractor dust, windmills,
even the way heard animals face can be indicative of wind direction.
Wind becomes a variable factor which must be anticipated and estimated
to secure a desired ground track. Wind strength normally varies
with altitude, becoming less as altitude decreases. Turbulence,
if encountered, should be introduced gradually both as to duration
and violence.
The FAR's relative to low level operations and altitudes are
covered. Requirements are 500' clear of any person or residence
and always able to make a safe landing without injury to persons
or property. The last part of the FAR makes possible simulated
emergencies from ground reference altitudes as long as a safe
landing area is available. With the mastery of the 'go around'
the student is ready for the low level situations that utilize
that particular skill.
An area with curved roads, rectangles, and straight lines that
is further away may be more effective for teaching. There are
many skills to teach during enroute flying. The instructor must
know about any obstructions, wires or other hazards. It is seldom
possible to find exactly the size and shape pattern required.
Be prepared to adapt. The instructor should have several different
practice areas. This is because on a given day you want to have
the best possible wind direction for doing the patterns. Calm
morning winds are best for the introductory ground reference flight
but the stronger afternoon winds are best for student pilot recognition
of the wind effects.
The only real difference between ground reference and other
flying is the difference, caused by wind, between your ground
track and your heading is more apparent. In a wind your groundspeed
and track will result from the sum of the vectors with respect
to the ground. First, you must determine the wind using whatever
ground source is available. Second, you must make a decision as
to how much "wind correction" you will apply. Third,
you compare your ground track with the one you want. Fourth, you
make a series of changes in one and two, to get the three you
want. Finding the "drift" is a matter of training your
eye to differentiate between where you are heading and where you
are going.
Written by Gene Whitt
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