Contents:

Introduction to Ground Reference
During the time that I am practicing flap descents and go arounds I try to make at least one descent over a gently curved channel or road that heads back home. I try to select one that will not require steep turns. Flying into the wind reduces the ground speed and required bank. For the last 'go around' I assign a recovery altitude of 700 or 800'. I direct the student to follow the road. He soon finds that the nose of the aircraft is an obstacle. He must sight ahead and alongside the path desired to select points of reference. He must anticipate the wind's effect in turns and straight-a-ways. He must keep his eyes outside the aircraft with only occasional referral to the altimeter. This is just a brief introduction but will focus the student's attention when doing the assigned reading about ground reference. Point out errors of tracking and altitude but not critically. Help the student locate rectangles for later use, and possible reference points as to compliance to the FARs regarding distance from persons or habitation.

To most efficiently use the flight time to this ground reference lesson I will climb to altitude en route. I do this so that we can practice power-off emergencies or descending spirals when we arrive at the ground reference area. Partial power should be applied during extended descents to prevent over-cooling. You could end up with an actual failure. During these descents help the student select ground reference patterns to be used. Once at a practice altitude the ground reference maneuvers are judged by smoothness, symmetry, and constant altitude.
Ground Reference
--Skill in performing ground reference is essential to airport flying
--Be able to describe the complexities of ground reference maneuvers before and during the performance.
--The PTS requires ground reference maneuvers and explanation as to 'why' you do what you do
--Pilot should be able to relate how ground maneuvers are related to specific flight conditions
--The IFR circle to land instrument requirement is related to turns about a circle.
--The pilot must be able to demonstrate and explain how the wind is influencing the ground pattern
--Ground reference requirements are 100 feet of altitude and 10 knots of airspeed.
--Division of attention inside and outside the aircraft are expected of the pilot during all maneuvers
--The ground track requires constant consideration of effective drift caused by wind velocity and direction
--A traffic watch at all times is a requirement. Demonstrate by obvious head movement and remarks
--The pilot must know the latest changes and version expected by the current PTS and how to perform
--The Airplane Flying Handbook (FAA-H-8083) and the PTS define how to perform maneuvers
--For example the entry and exit from the rectangular pattern are related to acceptable pattern entries
--The use of a variable bank is used to correct drift in a turn
--Know how to find and select suitable practice area.
--Know the difference between private pilot and commercial maneuvers

Why Ground Reference?
One of the weakest parts of flight instruction is the failure of the instructor to let the student know the 'why' of some of the maneuvers as they relate to actual flight operations. Ground reference is but one of these areas of weakness. Every ground reference maneuver has the potential of being applied in a real situation in the vicinity of an airport. We perform the four basics close to the ground so that the student can become familiar with the visual effects caused by ground movement under the aircraft. Again, this perception is part of the approach to landing. The apex of all ground reference maneuvers is the landing.

Flying relatively close to the ground greatly reduces the options you have in event of an emergency. It's not all bad since in case of a fire you can get to the ground more quickly. Select your area for ground reference in a sparsely inhabited area with plenty of emergency fields. At altitude we have always cleared prior to every turn. There is no reason not to clear for ground reference turns and every reason to continue what should be an ongoing habit. Once you have cleared, look over the nose during the turn.

As with airports you are learning to divide your attention between the ground and the airplane while maintaining control. If you do not properly divide your attention you will have difficulty maintaining a constant altitude and the desired ground track. At 4500' a hundred-foot altitude deviation is not as significant as it is at 500'. As changes in altitude and flight path occur you will be making cockpit adjustments using the division of attention skills required close to the ground. Ground reference maneuvers are performed to increase your comfort level with ground proximity before you begin intensive training with landings.

Any inability to understand and perform ground reference will appear again during the instructional phase on landings. Winds are never, but never, what ATC says they are or will be. The performance of the airplane in relation to the ground track and speed tells you the wind. When the airplane does not point where it is going, it is because of the wind. When the ground speed on a stabilized approach (correct airspeed) is seemingly too fast or slow, high or low, it is because of the wind. You must learn to fly airspeeds during landing approaches and interpret any variations in pattern and approach angle as due to wind.

When you have soloed and have an opportunity to practice ground reference on you own you enter a new world of practice. Only practice of the right kind will lead you beyond rote performance to competence and finally to confidence. You may recognize that you are having difficulty, and you may not. (Agnosia: You don't know what you don't know) Contact the instructor and talk/walk through the maneuver to make sure you understand the mechanics involved. This may solve the problem, but if it doesn't, a flight lesson is going to be the most economic solution. There is nothing worse you can do in flying than practicing a procedure incorrectly.

Cross-country flying not so apparently utilizes ground reference skills To fly a given course in any wind you will be required to make heading adjustments and bank adjustments. The higher altitudes of cross country make ground track adjustments more difficult to determine. The more readily you can make heading corrections for a desired ground track the more efficient will be your cross-country flying. Some examiners hold a pilot to 1/8 mile of his selected course. ( Good reason to make a 270 takeoff departure. This way you can start your time and course directly over the airport.

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. As a preliminary exercise, the patterns can be done by driving around light poles or making patterns on a large parking lot.

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-degree; turn in a 30-degree; 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 en route 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 ground speed 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.

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