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Figure 10-8. Approaching a busy airport with multiple runways and
listening to the Common Traffic Advisory Frequency (CTAF) for
the pattern being used because of the wind conditions.
Figure 10-9. After hearing other aircraft using the normal pattern as
described in the Airport/Facility Directory (A/FD), pilot descended
and entered the downwind leg (landing runway highlighted in
red) midfield within gliding distance of the runway in case of an
engine failure.
10-8
RUNWAY
Final Approach Departure
Downwind Leg
Base Leg
Upwind Leg
Crosswind Leg
Direction of Landing
Figure 10-10. Upwind leg.
that may be on the fi nal approach. This is especially important
since the WSC aircraft is in a tighter pattern and could be
fl ying onto the fi nal approach of faster airplanes.
The fi nal approach leg is a descending fl ightpath starting
from the completion of the base-to-fi nal turn and extending to
the point of touchdown. This is probably the most important
leg of the entire pattern because the pilot’s judgment and
procedures must be the sharpest to control the airspeed and
descent angle accurately while approaching the intended
touchdown point.
As stipulated in 14 CFR part 91, aircraft while on fi nal
approach to land or while landing have the right-of-way over
other aircraft in fl ight or operating on the surface. When two
or more aircraft are approaching an airport for the purpose of
landing, the aircraft at the lower altitude has the right of way.
A pilot should not take advantage of this rule to cut in front
of or overtake another aircraft on fi nal approach.
The departure leg of the rectangular pattern is a straight
course aligned with, and leading from, the takeoff runway.
This leg begins at the point the aircraft leaves the ground
and continues until the 90° turn onto the crosswind leg is
started. On the departure leg after takeoff, the pilot should
continue climbing straight ahead, and, if remaining in the
traffi c pattern, commence a turn to the crosswind leg beyond
the departure end of the runway within 300 feet of pattern
altitude. If departing the traffi c pattern, continue straight out
or exit with a 45° turn (to the left when in a left-hand traffi c
pattern; to the right when in a right-hand traffi c pattern)
beyond the departure end of the runway after reaching
pattern altitude.
An upwind leg is a course fl own parallel to the landing
runway, but in the same direction as the intended landing
direction. The upwind leg continues past a point abeam the
departure end of the runway to where a medium bank 90°
turn is made onto the crosswind leg. The upwind leg is also
the transitional part of the traffi c pattern when on the fi nal
approach and a go-around is initiated and climb attitude is
established. When a safe altitude is attained, the pilot should
commence a shallow bank turn to the right side of the runway.
This allows better visibility of the runway for departing
aircraft. [Figure 10-10]
The crosswind leg is the part of the rectangular pattern that is
horizontally perpendicular to the extended centerline of the
takeoff runway and is entered by making approximately a 90°
turn from the departure or upwind leg. On the crosswind leg,
the aircraft proceeds to the downwind leg position.
In most cases, the takeoff is made into the wind in which
case it is now approximately perpendicular to the aircraft’s
fl ightpath. As a result, the aircraft has to be turned or headed
slightly into the wind while on the crosswind leg to maintain
a ground track that is perpendicular to the runway centerline
extension.
Chapter Summary
Airport patterns provide organized air traffi c fl ows into and
out of an airport. An airport traffi c pattern is established
appropriate to the local conditions, including the direction and
placement of the pattern, altitude to be fl own, and procedures
for entering and leaving the pattern.
The legs of an airport pattern from takeoff are:
• Departure—direction of takeoff on the centerline of
the runway
• Crosswind—fi rst 90° turn fl ying perpendicular to the
takeoff direction
• Downwind—second 90° turn fl ying parallel to the
takeoff direction opposite the direction of takeoff and
landing
• Base—third 90° turn fl ying perpendicular towards the
runway centerline
• Final—forth 90° turn headed down the centerline of
the runway to land
Pilots must research and determine from prefl ight preparation
the possible runways and patterns for runways at the intended
　
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