Flying Handbook Menu > Ground Reference Maneuvers > Rectangular Course
Normally, the first ground reference maneuver
the pilot is introduced to is the rectangular course. [figure
figure6-4. Rectangular course.
The rectangular course is a training maneuver
in which the ground track of the airplane is equidistant from
all sides of a selected rectangular area on the ground. The
maneuver simulates the conditions encountered in an airport
traffic pattern. While performing the maneuver, the altitude
and airspeed should be held constant. The maneuver assists the
student pilot in perfecting:
• Practical application of the turn.
• The division of attention between the flightpath, ground
objects, and the handling of the airplane.
• The timing of the start of a turn so that the turn will
be fully established at a definite point over the ground.
• The timing of the recovery from a turn so that a definite
ground track will be maintained.
• The establishing of a ground track and the determination
of the appropriate “crab” angle.
Like those of other ground track maneuvers,
one of the objectives is to develop division of attention between
the flightpath and ground references, while controlling the
airplane and watching for other aircraft in the vicinity. Another
objective is to develop recognition of drift toward or away
from a line parallel to the intended ground track. This will
be helpful in recognizing drift toward or from an airport runway
during the various legs of the airport traffic pattern.
For this maneuver, a square or rectangular
field, or an area bounded on four sides by section lines or
roads (the sides of which are approximately a mile in length),
should be selected well away from other air traffic. The airplane
should be flown parallel to and at a uniform distance about
one-fourth to one-half mile away from the field boundaries,
not above the boundaries. For best results, the flightpath should
be positioned outside the field boundaries just far enough that
they may be easily observed from either pilot seat by looking
out the side of the airplane. If an attempt is made to fly directly
above the edges of the field, the pilot will have no usable
reference points to start and complete the turns. The closer
the track of the airplane is to the field boundaries, the steeper
the bank necessary at the turning points. Also, the pilot should
be able to see the edges of the selected field while seated
in a normal position and looking out the side of the airplane
during either a left-hand or right-hand course. The distance
of the ground track from the edges of the field should be the
same regardless of whether the course is flown to the left or
right. All turns should be started when the airplane is abeam
the corner of the field boundaries, and the bank normally should
not exceed 45°. These should be the determining factors
in establishing the distance from the boundaries for performing
Although the rectangular course may be entered
from any direction, this discussion assumes entry on a downwind.
On the downwind leg, the wind is a tailwind
and results in an increased groundspeed. Consequently, the turn
onto the next leg is entered with a fairly fast rate of roll-in
with relatively steep bank. As the turn progresses, the bank
angle is reduced gradually because the tailwind component is
diminishing, resulting in a decreasing groundspeed.
During and after the turn onto this leg (the
equivalent of the base leg in a traffic pattern), the wind will
tend to drift the airplane away from the field boundary. To
compensate for the drift, the amount of turn will be more than
The rollout from this turn must be such that
as the wings become level, the airplane is turned slightly toward
the field and into the wind to correct for drift. The airplane
should again be the same distance from the field boundary and
at the same altitude, as on other legs. The base leg should
be continued until the upwind leg boundary is being approached.
Once more the pilot should anticipate drift and turning radius.
Since drift correction was held on the base leg, it is necessary
to turn less than 90° to align the airplane parallel to
the upwind leg boundary. This turn should be started with a
medium bank angle with a gradual reduction to a shallow bank
as the turn progresses. The rollout should be timed to assure
paralleling the boundary of the field as the wings become level.
While the airplane is on the upwind leg, the
next field boundary should be observed as it is being approached,
to plan the turn onto the crosswind leg. Since the wind is a
headwind on this leg, it is reducing the airplane’s groundspeed
and during the turn onto the crosswind leg will try to drift
the airplane toward the field. For this reason, the roll-in
to the turn must be slow and the bank relatively shallow to
counteract this effect. As the turn progresses, the headwind
component decreases, allowing the groundspeed to increase. Consequently,
the bank angle and rate of turn are increased gradually to assure
that upon completion of the turn the crosswind ground track
will continue the same distance from the edge of the field.
Completion of the turn with the wings level should be accomplished
at a point aligned with the upwind corner of the field.
Simultaneously, as the wings are rolled level,
the proper drift correction is established with the airplane
turned into the wind. This requires that the turn be less than
a 90° change in heading. If the turn has been made properly,
the field boundary will again appear to be one-fourth to one-half
mile away. While on the crosswind leg, the wind correction angle
should be adjusted as necessary to maintain a uniform distance
from the field boundary.
As the next field boundary is being approached,
the pilot should plan the turn onto the downwind leg. Since
a wind correction angle is being held into the wind and away
from the field while on the crosswind leg, this next turn will
require a turn of more than 90°. Since the crosswind will
become a tailwind, causing the groundspeed to increase during
this turn, the bank initially should be medium and progressively
increased as the turn proceeds. To complete the turn, the rollout
must be timed so that the wings become level at a point aligned
with the crosswind corner of the field just as the longitudinal
axis of the airplane again becomes parallel to the field boundary.
The distance from the field boundary should be the same as from
the other sides of the field.
Usually, drift should not be encountered on
the upwind or the downwind leg, but it may be difficult to find
a situation where the wind is blowing exactly parallel to the
field boundaries. This would make it necessary to use a slight
wind correction angle on all the legs. It is important to anticipate
the turns to correct for groundspeed, drift, and turning radius.
When the wind is behind the airplane, the turn must be faster
and steeper; when it is ahead of the airplane, the turn must
be slower and shallower. These same techniques apply while flying
in airport traffic patterns.
Common errors in the performance of rectangular
• Failure to adequately clear the area.
• Failure to establish proper altitude prior to entry.
(Typically entering the maneuver while descending.)
• Failure to establish appropriate wind correction angle
resulting in drift.
• Gaining or losing altitude.
• Poor coordination. (Typically skidding in turns from
a downwind heading and slipping in turns from an upwind heading.)
• Abrupt control usage.
• Inability to adequately divide attention between airplane
control and maintaining ground track.
• Improper timing in beginning and recovering from turns.
• Inadequate visual lookout for other aircraft.