Glidepath with Wind
Idle Power
High Wind
Intended LandingEffect of Wind on GlidepathB
Normal Glidepath No Headwind
Idle Power
Intended LandingGlidepath in Calm WindsA
Decreased Glidepath
in High Wind
Idle Power
Power Application
Maintains Gli
depath to Runway in High Winds
Intended Landing
High Wind
Effect on Glidepath with Power Application in High WindsD
Too far away base leg setup in high winds
Glidepath with wind
Idle Power
Set up a base closer to runway
In high winds because glidepath is steeper
Intended Landing
High Wind
High Wind Base Leg SetupC
Proper base Leg setup in high winds
Figure 11-16. Headwinds for final approach.
the base leg must be made closer to the runway to land in
the intended area in a headwind. [Figure 11-16 C] However,
if more headwind is experienced during fi nal approach,
increased power is required to make the intended landing
area. [Figure 11-16 D]
Naturally, the pilot does not have control over the wind but
may correct for its effect on the aircraft’s descent by adjusting
the base leg of the pattern. The wind can vary signifi cantly
at different attitudes and locations in the pattern. If the pilot
does not notice the headwind until the base leg, the base
Figure 11-17. Modified base leg if winds higher than intended are encountered during the base leg of the pattern.
NORM
AL CALM WIND APPROACH
If crosswind encountered
on base leg—
modify base leg
If tailwind encountered
on downwind leg—
modify base leg
Intended Touchdown Point
leg should be cut short and the pilot should head towards
the runway sooner. This would provide the best possibility
of making the runway if there is an engine failure in this
situation. [Figure 11-17]
Additionally, during strong headwinds, more energy (power
and airspeed) should be used since the wind gradient (slowing
of the wind near the ground because of the friction of the
ground) could reduce the airspeed and cause a stall on
approach near the ground in higher winds.
Stabilized Approach Concept
A stabilized approach is one in which the pilot establishes and
maintains a constant angle glidepath toward a predetermined
point on the landing runway. It is based on the pilot’s judgment
of certain visual clues and depends on the maintenance of a
constant fi nal descent airspeed.
An aircraft descending on fi nal approach at a constant rate
and airspeed is traveling in a straight line toward a point on
the ground ahead. This point is not the point on which the
aircraft touches down because some fl oat inevitably occurs
during the roundout.
The point toward which the aircraft is progressing is termed
the “aiming point.” [Figure 11-18] It is the point on the
ground at which, if the aircraft maintains a constant glidepath
and was not rounded out for landing, it would strike the
ground. To a pilot moving straight ahead toward an object,
it appears to be stationary. This is how the aiming point can
be distinguished—it does not move. However, objects in
front of and beyond the aiming point do appear to move as
the distance is closed, and they appear to move in opposite
directions. During instruction in landings, one of the most
important skills a student pilot must acquire is the use of
visual cues to accurately determine the true aiming point
from any distance out on fi nal approach. From this, the pilot
is able not only to determine if the glidepath results in an
undershoot or overshoot, but also to predict the touchdown
point to within a few feet taking into account fl oat during
roundout.
Final Approach
Roundout starts
Distance Traveled Past Aiming
Point to Touchdown Touchdown
Aiming point is
where descent angle
intersects ground
Figure 11-18. Stabilized approach.
For a constant angle glidepath, the distance between the
horizon and the aiming point remain constant. If a fi nal
approach descent has been established but the distance
between the perceived aiming point and the horizon
appears to increase (aiming point moving down, away from
the horizon), then the true aiming point and subsequent
touchdown point is farther down the runway. If the distance
between the perceived aiming point and the horizon decreases
(aiming point moving up toward the horizon), the true aiming
point is closer than perceived.
When the aircraft is established on fi nal approach, the shape
of the runway image also presents clues regarding what
must be done to maintain a stabilized approach to a safe
landing. A runway is normally shaped in the form of an
elongated rectangle. When viewed from the air during the
approach, perspective causes the runway to assume the shape
of a trapezoid with the far end appearing narrower than the
approach end, and the edge lines converging in the distance.
If the aircraft continues down the glidepath at a constant angle
(stabilized), the image the pilot sees is still trapezoidal but
of proportionately larger dimensions.
During a stabilized approach, the runway shape does not
change. [Figure 11-19] If the approach becomes shallower,
the runway appears to shorten and become wider. Conversely,
if the approach is steepened, the runway appears to become
longer and narrower. [Figure 11-20]
The objective of a stabilized approach is to select an
appropriate touchdown point on the runway and adjust
the glidepath so that the true aiming point and the desired
touchdown point coincide. Immediately after rolling out of
base leg and onto fi nal approach, the pilot should adjust the
speed so that the aircraft descends directly toward the aiming
point. With the approach set up in this manner, the pilot is
free to devote full attention to outside references. The pilot
should not stare at any one place, but rather scan from one
area to another, such as from the aiming point to the horizon,
to the trees and bushes along the runway, to an area well
short of the runway, and back to the aiming point. In this
way, the pilot is more apt to perceive a deviation from the
desired glidepath and whether or not the aircraft is proceeding
directly toward the aiming point.
If the pilot perceives any indication that the aiming point
on the runway is not where desired, an adjustment must be
made to the glidepath. This in turn moves the aiming point.
For instance, if the pilot perceives that the aiming point
is signifi cantly short of the desired touchdown point and
results in an undershoot, an increase in power is warranted.
The minimum airspeed recommended by the manufacturer
must be maintained. This results in a shallowing of the
glidepath with the resultant aiming point moving toward the
desired touchdown point. Conversely, if the pilot perceives
that the aiming point is farther down the runway than the
desired touchdown point and results in an overshoot, the
glidepath should be steepened by an increase in speed with
the throttle at idle. It is essential that deviations from the
desired glidepath be detected early, so that only slight and
infrequent adjustments to glidepath are required.
If a situation arises in which the required corrections become
larger (and possibly more frequent) as the aircraft draws closer
to the runway, an unstabilized approach results.
Common errors in the performance of normal approaches and
landings include the following:
• Not realizing there is a tailwind during downwind to
complete an early base
• Inadequate wind drift correction on the base leg
Too High
Too Low
Desired Descent Angle
Figure 11-20. Change in runway shape if approach becomes
narrow or steep.
4,000' x 100' Runway
1,600' From Threshold
100' Altitude
Same Runway, Same Approach Angle
800' From Threshold
50' Altitude
Same Runway, Same Approach Angle
400' From Threshold
25' Altitude
Figure 11-19. Runway shape during stabilized approach.
• Overshooting or undershooting the turn onto fi nal
approach
• Unstabilized approach
• Attempting to maintain altitude or reach the runway
by slowing WSC aircraft below the minimum
manufacturer’s recommended approach airspeed
• Gaining any altitude during the roundout
• Rounding out too fast during landing
• Focusing too close to the aircraft, resulting in an overly
high roundout
• Focusing too far from the aircraft, resulting in an overly
low roundout
• Touching down prior to attaining proper landing
attitude
• Failure to lower the nose after the rear wheels touch
down
• Failure to lower the nose after the front wheel touches
down
• Excessive braking after touchdown
Go-Around ( Rejected Landings)
Whenever landing conditions are not satisfactory, a go-around
is warranted. There are many factors that can contribute
to unsatisfactory landing conditions. Situations such as
ATC requirements, unexpected appearance of hazards on
the runway, overtaking another aircraft, wind shear, wake
turbulence, mechanical failure and/or an unstabilized approach
are all examples of reasons to discontinue a landing approach
and make another approach under more favorable conditions.
The assumption that an aborted landing is invariably the
consequence of a poor approach, which in turn is due to
insuffi cient experience or skill, is a fallacy. The go-around is
not strictly an emergency procedure. It is a normal maneuver
that may at times be used in an emergency situation. Like
any other normal maneuver, the go-around must be practiced
and perfected. The fl ight instructor should emphasize early
in the student pilot’s training that the go-around maneuver is
an alternative to any approach and/or landing.
Although the need to discontinue a landing may arise at any
point in the landing process, the most critical go-around is
one started when very close to the ground. Therefore, the
earlier a condition that warrants a go-around is recognized,
the safer the go-around/rejected landing is. The go-around
maneuver is not inherently dangerous in itself. It becomes
dangerous only when delayed unduly or executed improperly.
Delay in initiating the go-around normally stems from one
or both of two sources:
1. Landing expectancy or set—the anticipatory belief
that conditions are not as threatening as they are and
that the approach will surely be terminated with a safe
landing, and
2. Pride—the mistaken belief that the act of going around
is an admission of failure to execute the approach
properly. The improper execution of the go-around
maneuver stems from a lack of familiarity with the
two cardinal principles of the procedure: power and
speed.
Power
Power is the pilot’s fi rst concern. The instant the pilot decides
to go around, full or maximum allowable takeoff power must
be applied smoothly and without hesitation and held until
fl ying speed and controllability are restored. Applying only
partial power in a go-around is never appropriate unless the
WSC aircraft is at an unusually high pitch angle. The pilot
must be aware of the degree of inertia that must be overcome
before an aircraft that is settling toward the ground can regain
suffi cient airspeed to become fully controllable and capable
of turning safely or climbing. The application of power
should be smooth as well as positive. Abrupt movements of
the throttle in some aircrafts causes the engine to falter.
Speed
Speed is always critical when close to the ground. When
power is added, a deliberate effort on the part of the pilot
is required to keep the nose from pitching up prematurely.
The aircraft executing a go-around must be maintained well
beyond the stall point before any effort is made to gain
altitude or to execute a turn. Raising the nose too early may
produce a stall from which the aircraft could not recover if the
go-around is performed at a low altitude. The manufacturer’s
recommended climb speed should be established and
maintained during the initial phase of the go around.
A concern for quickly regaining altitude during a go-around
produces a natural tendency to push the nose up. The pilot
executing a go-around must accept the fact that an aircraft
will not climb until it can fl y, and it will not fl y below stall
speed. In some circumstances, it may be desirable to lower
the nose briefl y to gain airspeed. [Figure 11-21]
During the initial part of an extremely low go-around, the
aircraft may settle onto the runway and bounce. This situation
is not particularly dangerous if the aircraft is kept straight and
a constant, safe speed is maintained. The aircraft is rapidly
approaching safe fl ying speed and the advanced power will
cushion any secondary touchdown.
Roundout and
Touchdown
Stabilized Approach at 1.3 Vs Over Obstacle or
to Start of Short Landing Area
Nose Down for Aerodynamic braking and
To Provide Maximum Brake System Effectiveness
Figure 11-22. Short field landing.
Obstruction seen on runway and
go-around initiated during final
approach or round out—
Full power applied
Final Approach Normal Climbout
(at Vy after climb speed is reached)
Figure 11-21. Go-around procedure.
Common errors in the performance of go-around (rejected
landings) are:
• Failure to recognize a condition that warrants a
rejected landing,
• Indecision,
• Delay in initiating a go-round,
• Failure to apply maximum allowable power in a timely
manner,
• Improper speed,
• Attempting to climb out of ground effect prematurely,
and
• Failure to adequately compensate for torque/P-
factor.
Short and Soft Field Landing Techniques
Many WSC aircraft land routinely on short and soft fi elds.
The type of WSC and appropriate systems for short and
soft fi eld was discussed in the Components and Systems
chapter. Here, some techniques for these landing areas are
discussed.
Short-Field Approaches and Landings
Short-field approaches and landings require the use of
procedures for approaches and landings at fields with
a relatively short landing area or where an approach is
made over obstacles that limit the available landing area.
[Figure 11-22] As in short-fi eld takeoffs, it is one of the most
critical of the maximum performance operations. It requires
that the pilot fl y the aircraft at one of its crucial performance
capabilities while close to the ground in order to land safely
within confi ned areas.
To land within a short fi eld or confi ned area, the pilot must
have precise, positive control of the rate of descent and
airspeed to produce an approach that clears any obstacles,
results in little or no fl oating during the roundout, and permits
the aircraft to be stopped in the shortest possible distance. As
with the short takeoff maneuver, this should only be done
for unusual situations or emergency operations and is not
recommended. There are numerous airports, fi elds, and other
areas to land, so prefl ight planning should avoid short-fi eld
landings. However, short-fi eld procedures are provided for
information.
A stabilized approach is essential. These procedures generally
involve the starting to fi nal approach from an altitude of at
least 500 feet higher than the touchdown area. In the absence
of a manufacturer’s recommended approach speed and in
calm winds, example approach speeds are 1.3 times the stall
speed or 8 knots above the stall speed. For example, in an
aircraft that stalls at 30 knots with power off, the approach
speed should be 38 to 40 knots. This maneuver should not
be performed in gusty air because of the slow speeds and
close proximity to the ground. If it is necessary to accomplish
in gusty air, no more than one-half the gust factor should
be added. An excessive amount of airspeed could result
in a touchdown with an after-landing roll that exceeds the
available landing area.
For the steepest glide angle to clear obstacles such as trees or
buildings, the maneuver should be performed at idle power; if
the landing surface does not have obstacles that must be fl own
over, power on approach may be used to reach the landing
surface. The pilot should simultaneously adjust the power and
the speed to establish and maintain the proper descent angle.
A coordinated combination of both speed and power (if used)
adjustments is required to set up a stabilized approach.
The short-fi eld approach and landing is in reality an accuracy
approach to a spot landing. The procedures previously
outlined in the section on the stabilized approach concept
should be used. If it appears that the obstacle clearance is
excessive and touchdown will occur well beyond the desired
spot leaving insuffi cient room to stop, lowering the pitch
attitude and reducing power (if used) steepen the descent path
and increase the rate of descent. If it appears that the descent
angle will not ensure safe clearance of obstacles, power
should be increased to shallow the descent path and decrease
the rate of descent. Care must be taken to avoid an excessively
low airspeed. If the speed is allowed to become too low, an
increase in pitch and application of full power may result in a
further rate of descent. This occurs when the AOA is too great
and creating so much drag that the maximum available power
is insuffi cient to overcome it. This is generally referred to as
operating in the region of reversed command or operating on
the back side of the power curve.
Because the final approach over obstacles is made at
a relatively steep approach angle and at the minimum
manufacturer’s recommended approach speed, the initiation
of the roundout must be judged accurately to avoid fl ying
into the ground or stalling prematurely and sinking rapidly.
A lack of fl oating during the roundout with suffi cient control
to touch down properly is one verifi cation that the approach
speed was correct.
Upon touchdown, the nose should be brought down
completely for aerodynamic braking and providing maximum
pressure on the wheels for using the braking system.
Immediately upon touchdown, appropriate braking should be
applied to minimize the after-landing roll. The aircraft should
be stopped within the shortest possible distance consistent
with safety and controllability. If the situation arises and
the minimum landing distance is required, the WSC can be
landed above the normal speed, the nose brought down for
aerodynamic braking while the brakes are applied for the
shortest distance possible.
Soft and Rough Field Approaches and Landings
Landing on fi elds that are rough or have soft surfaces, such as
snow, sand, mud, tall grass, or a rocky/bumpy fi eld requires
unique procedures. When landing on such surfaces, the
objective is to touch down as smoothly as possible and at
the lowest possible landing speed. The pilot must control the
aircraft so that the wings support the weight of the aircraft as
long as is practical to minimize drag and stresses imposed on
the landing gear by the rough or soft surface.
Similar to the soft fi eld for takeoff, proper gear—specifi cally
big tires with a large wing and overall low weight—should be
utilized for soft or rough fi eld operations. Refer to appropriate
gear and warnings in Chapter 7, Takeoff and Departure
Climbs, for soft or rough fi eld operation as a prerequisite
for this chapter.
The approach for the soft fi eld landing is similar to the normal
approach used for operating into long, fi rm landing areas.
The major difference between the two is that, during the soft
or rough fi eld landing, the distance on the soft/rough fi eld is
minimized and the weight is kept off the wheels by the lift
of the wing when on the soft/rough fi eld. Power can be used
throughout the level-off and touchdown to ensure touchdown
at the lowest possible airspeed, with the WSC aircraft fl own
onto the ground with the weight fully supported by the wings.
The touchdown should be planned for minimal taxi distance
to the stopping point so there is the shortest possible distance
with weight on the landing gear on the rough/soft surface.
[Figure 11-23]
PARKING
AREA
MINIMUM DISTANCE BETWEEN
TOUCHDOWN AND PARKING AREA
WITH NOSE HIGH TO MINIMIZE
WEIGHT ON FRONT WHEEL
DECELERATE IN GROUND EFFECTNORMAL APPROACH
Touch down
as late as possible
Figure 11-23. Soft/rough field approach and landing.
Touchdown on a soft or rough fi eld should be made at the
lowest possible airspeed with the aircraft in a nose-high pitch
attitude. After the main wheels touch the surface, the pilot
should hold bar-forward pressure to keep the nosewheel off
the surface. Using forward control bar pressure and engine
power, the pilot can control the rate at which the weight of
the aircraft is transferred from the wings to the wheels.
Field conditions may warrant that the pilot maintain a fl ight
condition where the main wheels are just touching the surface,
but the weight of the aircraft is still being supported by the
wings until a suitable taxi surface is reached. At any time
during this transition phase, before the weight of the aircraft
is being supported by the wheels and before the nosewheel
is on the surface, the pilot should be able to apply full power
and perform a safe takeoff (obstacle clearance and fi eld length
permitting) should the pilot elect to abandon the landing.
Once committed to a landing, the pilot should gently lower
the nosewheel to the surface. A slight reduction of power
usually helps ease the nosewheel down.
The use of brakes on a soft fi eld is not needed and should
be avoided as this tends to impose a heavy load on the nose
gear due to premature or hard contact with the landing
surface causing the nosewheel to dig in. The soft or rough
surface itself provides suffi cient reduction in the aircraft’s
forward speed. Often upon landing on a very soft fi eld, the
pilot needs to increase power to keep the aircraft moving and
from becoming stuck on the soft surface.
Power-on Approach and Landing for
Turbulant Air
Power-on approaches at an airspeed above the normal
approach speed should be used for landing in turbulent
air. This provides for more energy and positive control
of the aircraft when strong horizontal wind gusts, wind
sheer, or up and down drafts, are experienced. Like other
power-on approaches (when the pilot can vary the amount
of power), a coordinated combination of both speed and
power adjustments is usually required. It is easiest to think
of fl ying the aircraft onto the ground at an airspeed above
the stall speed. The additional power provides the pilot the
ability to reduce the descent rate to touch the wheels gently
to the surface at a higher speed. Landing in turbulent air is
where practice and experience in energy management are
utilized. This precise coordination of power and speed for
higher energy landings should fi rst be practiced in calm air
and can be used as the next step in learning landings after the
student becomes profi cient at low approaches.
To determine the additional approach speed to fl ying in
turbulence, one procedure is to use the normal approach
speed plus one-half of the wind gust factors. The wind gust
factor is determined by how much the airspeed varies while
fl ying. If the normal approach speed is 50 knots and the wind
gusts are at 15 knots, an airspeed of 57 knots is appropriate.
Another method is to ensure the aircraft is at least at VY speed
plus the wind gust factor. In any case, the airspeed that the
aircraft manufacturer recommends.
An adequate amount of power should be used to maintain the
proper airspeed and descent path throughout the approach
and the throttle retarded to idling position only after the
main wheels contact the landing surface. Care must be
exercised in not closing the throttle before the pilot is ready
for touchdown. In this situation, the sudden or premature
closing of the throttle may cause a sudden increase in the
descent rate that could result in a hard landing.
Landings from power-on approaches in turbulence should
be such that the touchdown is made with the aircraft in
approximately level fl ight attitude. The pitch attitude at