Recovery from this situation requires prompt and positive application of power prior to occurrence of the stall. This may be followed by
a normal landing if sufficient runway is available—otherwise the pilot should execute a go-around immediately.
If the round out is late and uncorrected, the nose-wheel may strike the runway first, causing the nose to bounce upward. Do not attempt
to force the airplane back onto the ground; execute a go-around immediately.
Floating During Round Out
If the airspeed on final approach is excessive, it usually results in the airplane floating. [ Figure 9-33] Before touchdown can be made,
the airplane may be well past the desired landing point and the available runway may be insufficient. When diving the airplane on final
approach to land at the proper point, there is an appreciable increase in airspeed. The proper touchdown attitude cannot be established
without producing an excessive AOA and lift. This causes the airplane to gain altitude or balloon.
Figure 9-33. Floating during round out.
Any time the airplane floats, judgment of speed, height, and rate of sink needs to be especially acute. The pilot should smoothly and
gradually adjust the pitch attitude as the airplane decelerates to touchdown speed and starts to settle, so the proper landing attitude is
attained at the moment of touchdown. The slightest error in judgment and timing results in either ballooning or bouncing.
The recovery from floating is dependent upon the amount of floating and the effect of any crosswind, as well as the amount of runway
remaining. Since prolonged floating utilizes considerable runway length, it should be avoided especially on short runways or in strong
crosswinds. If a landing cannot be made on the first third of the runway, or the airplane drifts sideways, execute a go-around.
Ballooning During Round Out
If the pilot misjudges the rate of sink during a landing and thinks the airplane is descending faster than it should, there is a tendency to
increase the pitch attitude and AOA too rapidly. This not only stops the descent, but actually starts the airplane climbing. This climbing
during the round out is known as ballooning. [Figure 9-34] Ballooning is dangerous because the height above the ground is increasing
and the airplane is rapidly approaching a stalled condition. The altitude gained in each instance depends on the airspeed or the speed with
which the pitch attitude is increased.
Figure 9-34. Ballooning during roundout.
Depending on the severity of ballooning, the use of throttle is helpful in cushioning the landing. By adding power, thrust is increased to
keep the airspeed from decelerating too rapidly and the wings from suddenly losing lift, but throttle should be closed immediately after
touchdown. Torque effects vary as power is changed, and it is necessary to use rudder pressure to keep the airplane straight as it settles
onto the runway.
The pilot needs to be extremely cautious of ballooning when there is a crosswind present because the crosswind correction may be
inadvertently released or it may become inadequate. Because of the lower airspeed after ballooning, the crosswind affects the airplane
more. Consequently, the wing has to be lowered even further to compensate for the increased drift. It is imperative that the pilot makes
certain that the appropriate wing is down and that directional control is maintained with opposite rudder. If there is any doubt, or the
airplane starts to drift, the pilot should execute a go-around.
When ballooning is excessive, it is best to execute a go-around immediately and not attempt to salvage the landing. Power should be
applied before the airplane enters a stalled condition.
Bouncing During Touchdown
When the airplane contacts the ground with a sharp impact as the result of an improper attitude or an excessive rate of sink, it tends to
bounce back into the air. Though the airplane’s tires and shock struts provide some springing action, the airplane does not bounce like a
rubber ball. Instead, it rebounds into the air because the wing’s AOA was abruptly increased, producing a sudden addition of lift. [Figure
9-35]
Figure 9-35. Bouncing during touchdown.
The abrupt change in AOA is the result of inertia instantly forcing the airplane’s tail downward when the main wheels contact the ground
sharply. The severity of the bounce depends on the airspeed at the moment of contact and the degree to which the AOA or pitch attitude
was increased.
Since a bounce occurs when the airplane makes contact with the ground before the proper touchdown attitude is attained, it is almost
invariably accompanied by the application of excessive back-elevator pressure. This is usually the result of the pilot realizing too late
that the airplane is not in the proper attitude and attempting to establish it just as the second touchdown occurs.
The corrective action for a bounce is the same as for ballooning and similarly depends on its severity. When it is very slight and there
is no extreme change in the airplane’s pitch attitude, a follow-up landing may be executed by applying sufficient power to cushion the
subsequent touchdown and smoothly adjusting the pitch to the proper touchdown attitude.
In the event a very slight bounce is encountered while landing with a crosswind, crosswind correction needs to be maintained while the
next touchdown is made. Since the subsequent touchdown is made at a slower airspeed, the upwind wing has to be lowered even further
to compensate for drift.
Extreme caution and alertness should be exercised any time a bounce occurs, but particularly when there is a crosswind. Pilots should not
release the crosswind correction. When one main wheel of the airplane strikes the runway, the other wheel touches down immediately
afterwards, and the wings become level. Then, with no crosswind correction as the airplane bounces, the wind causes the airplane to roll
with the wind, thus exposing even more surface to the crosswind and increasing any drift.
When a bounce is severe, the safest procedure is to execute a go-around immediately. The pilot should not attempt to salvage the
landing. Apply full power while simultaneously maintaining directional control and lowering the nose to a safe climb attitude. The go-
around procedure should be continued even though the airplane may descend and another bounce may be encountered. Landing from
a bad bounce should not be attempted, since airspeed diminishes very rapidly in the nose-high attitude, and a stall may occur before a
subsequent touchdown can be made.
Porpoising
In a bounced landing that is improperly recovered, the airplane comes in nose first, initiating a series of motions imitating the jumps and
dives of a porpoise. [Figure 9-36] The improper airplane attitude at touchdown may be caused by inattention, not knowing where the
ground is, miss-trimming, or forcing the airplane onto the runway.
Figure 9-36. Porpoising.
Ground effect decreases elevator control effectiveness and increases the effort required to raise the nose. Not enough elevator or stabilator
trim can result in a nose low contact with the runway and a porpoise develops.
Porpoising can also be caused by improper airspeed control. Usually, if an approach is too fast, the airplane floats and the pilot tries
to force it on the runway when the airplane still wants to fly. A gust of wind, a bump in the runway, or even a slight tug on the control
wheel sends the airplane aloft again.
The corrective action for a porpoise is the same as for a bounce and similarly depends on its severity. When it is very slight and there
is no extreme change in the airplane’s pitch attitude, a follow-up landing may be executed by applying sufficient power to cushion the
subsequent touchdown and smoothly adjusting the pitch to the proper touchdown attitude.
When pilots attempt to correct a severe porpoise with flight control and power inputs, the inputs are often untimely may increase the
severity of each successive contact with the surface. These unintentional and increasing pilot-induced oscillations may lead to damage
or collapse of the nose gear. When porpoising is severe or seems to be getting worse, the safest procedure is to execute a go-around
immediately by applying full power while simultaneously maintaining directional control and lowering the nose to a safe climb attitude.
Wheelbarrowing
When a pilot permits the airplane weight to become concentrated about the nose-wheel during the takeoff or landing roll, a condition
known as wheelbarrowing occurs. Wheelbarrowing may cause loss of directional control during the landing roll because braking action
is ineffective, and the airplane tends to swerve or pivot on the nose-wheel, particularly in crosswind conditions. One of the most common
causes of wheelbarrowing during the landing roll is a simultaneous touchdown of the main and nose-wheel with excessive speed,
followed by application of forward pressure on the elevator control. Usually, the situation can be corrected by smoothly applying back-
elevator pressure.
Wheelbarrowing does not occur if the pilot achieves and maintains the correct landing attitude, touches down at the proper speed, and
gently lowers the nose-wheel while losing speed on rollout. However, if wheelbarrowing is encountered and runway and other conditions
permit, it is advisable to promptly initiate a go-around. If the pilot decides it's safer to stay on the ground rather than attempt a go-around
when directional control is lost, close the throttle and adjust the pitch attitude smoothly but firmly to the proper landing attitude.
Hard Landing
When the airplane contacts the ground during landings, its vertical speed is instantly reduced to zero. Unless provisions are made to
slow this vertical speed and cushion the impact of touchdown, the force of contact with the ground could cause structural damage to the
airplane.
The purpose of pneumatic tires, shock absorbing landing gear, and other devices is to cushion the impact and to increase the time in
which the airplane’s vertical descent is stopped. The importance of this cushion may be understood from the computation that a 6-inch
free fall on landing is roughly equal to a 340 fpm descent. Within a fraction of a second, the airplane gets slowed from this rate of vertical
descent to zero without damage.
During this time, the landing gear, together with some aid from the lift of the wings, supplies whatever force is needed to counteract the
force of the airplane’s inertia and weight. However, the lift decreases rapidly as the airplane’s forward speed is decreased, and the force
on the landing gear increases by the impact of touchdown. When the descent stops, the lift is practically zero, leaving the landing gear
alone to carry both the airplane’s weight and inertia force. The load imposed at the instant of touchdown may easily be three or four times
the actual weight of the airplane depending on the severity of contact.
Touchdown in a Drift or Crab
At times, it is necessary to correct for wind drift by crabbing on the final approach. If the round out and touchdown are made while the
airplane is drifting or in a crab, it contacts the ground while moving sideways. This imposes extreme side loads on the landing gear and,
if severe enough, may cause structural failure.
The most effective method to prevent drift is the wing-low method. This technique keeps the longitudinal axis of the airplane aligned with
both the runway and the direction of motion throughout the approach and touchdown. There are three factors that cause the longitudinal
axis and the direction of motion to be misaligned during touchdown: drifting, crabbing, or a combination of both.
If the pilot does not take adequate corrective action to avoid drift during a crosswind landing, the main wheels’ tire tread offers resistance
to the airplane’s sideward movement with respect to the ground. Consequently, any sideward velocity of the airplane is abruptly
decelerated, as shown in Figure 9-37. This creates a moment around the main wheel when it contacts the ground, tending to overturn or
tip the airplane. If the upwind wingtip is raised by the action of this moment, all the weight and shock of landing is borne by one main
wheel. This concentration of forces may cause tire failure or structural damage.
Figure 9-37. Drifting during touchdown.
Not only are the same factors present that are attempting to raise a wing, but the crosswind is also acting on the fuselage surface behind
the main wheels, tending to yaw (weathervane) the airplane into the wind. This often results in a ground loop.
Ground Loop
A ground loop is an uncontrolled turn during ground operation that may occur while taxiing or taking off. However, an airplane is
especially vulnerable to this occurrence during the after-landing roll. A ground loop may result if the pilot fails to control an initial
swerve. Drift or weathervaning may cause the initial swerve. Careless use of the rudder, an uneven ground surface, or a soft spot that
retards one main wheel of the airplane may also cause a swerve. In any case, the initial swerve tends to make the airplane ground loop,
whether it is a tailwheel-type or nose-wheel type. [Figure 9-38]
Figure 9-38. Start of a ground loop.
Nose-wheel type airplanes are somewhat less prone to ground loop than tailwheel-type airplanes. Since the center of gravity (CG) is
located forward of the main landing gear on these airplanes, any time a swerve develops, centrifugal force acting on the CG tends to
stop the swerving action.
If the airplane touches down while drifting or in a crab, apply aileron toward the high wing and stop the swerve with the rudder. Brakes
are used to correct for turns or swerves only when the rudder is inadequate. Exercise caution when applying corrective brake action
because it is very easy to over control and aggravate the situation.
If brakes are used, sufficient brake is applied on the low-wing wheel (outside of the turn) to stop the swerve. When the wings are
approximately level, the new direction should be maintained until the airplane has slowed to taxi speed or has stopped.
In nose-wheel airplanes, a ground loop is almost always a result of wheelbarrowing. A pilot should be aware that even though the nose-
wheel type airplane is less prone than the tailwheel-type airplane, virtually every type of airplane, including large multiengine airplanes,
can be made to ground loop when sufficiently mishandled.
Wing Rising After Touchdown
When landing in a crosswind, there may be instances when a wing rises during the after-landing roll. This may occur whether or not there
is a loss of directional control, depending on the amount of crosswind and the degree of corrective action.
Any time an airplane is rolling on the ground in a crosswind condition, the upwind wing is receiving a greater force from the wind than
the downwind wing. This causes a lift differential. Also, as the upwind wing rises, there is an increase in the AOA, which increases lift
on the upwind wing, rolling the airplane downwind.
When the effects of these two factors are great enough, the upwind wing may rise even though directional control is maintained. If no
correction is applied, it is possible that the upwind wing rises sufficiently to cause the downwind wing to strike the ground.
In the event a wing starts to rise during the landing roll, the pilot should immediately apply more aileron pressure toward the high wing
and continue to maintain direction. The sooner the aileron control is applied, the more effective it is. The further a wing is allowed to
rise before taking corrective action, the more airplane surface is exposed to the force of the crosswind. This diminishes the effectiveness
of the aileron.
Hydroplaning
Hydroplaning is a condition that can exist when an airplane has landed on a runway surface contaminated with standing water, slush,
or wet snow. Hydroplaning can have serious adverse effects on ground controllability and braking efficiency. The three basic types of
hydroplaning are dynamic hydroplaning, reverted rubber hydroplaning, and viscous hydroplaning. Any one of the three can render an
airplane partially or totally uncontrollable anytime during the landing roll.
Dynamic Hydroplaning
Dynamic hydroplaning is a relatively high-speed phenomenon that occurs when there is a film of water on the runway that is at least one-
tenth of an inch deep. As the speed of the airplane and the depth of the water increase, the water layer builds up an increasing resistance
to displacement, resulting in the formation of a wedge of water beneath the tire. At some speed, termed the hydroplaning speed (Vₚ),
the water pressure equals the weight of the airplane, and the tire is lifted off the runway surface. In this condition, the tires no longer
contribute to directional control and braking action is nil.
Dynamic hydroplaning is related to tire inflation pressure. Data obtained during hydroplaning tests have shown the minimum dynamic
hydroplaning speed (Vₚ) of a tire to be 8.6 times the square root of the tire pressure in pounds per square inch (PSI). For an airplane
with a main tire pressure of 24 PSI, the calculated hydroplaning speed would be approximately 42 knots. It is important to note that
the calculated speed referred to above is for the start of dynamic hydroplaning. Once hydroplaning has started, it may persist to a
significantly slower speed depending on the type being experienced.
Reverted Rubber Hydroplaning
Reverted rubber (steam) hydroplaning occurs during heavy braking that results in a prolonged locked-wheel skid. Only a thin film of
water on the runway is required to facilitate this type of hydroplaning. The tire skidding generates enough heat to cause the rubber in
contact with the runway to revert to its original uncured state. The reverted rubber acts as a seal between the tire and the runway and
delays water exit from the tire footprint area. The water heats and is converted to steam, which supports the tire off the runway.
Reverted rubber hydroplaning frequently follows an encounter with dynamic hydroplaning, during which time the pilot may have the
brakes locked in an attempt to slow the airplane. Eventually the airplane slows enough to where the tires make contact with the runway
surface and the airplane begins to skid. The remedy for this type of hydroplaning is to release the brakes and allow the wheels to spin up
and apply moderate braking. Reverted rubber hydroplaning is insidious in that the pilot may not know when it begins, and it can persist
to very slow groundspeeds (20 knots or less).
Viscous Hydroplaning
Viscous hydroplaning is due to the viscous properties of water. A thin film of fluid no more than one-thousandth of an inch in depth is all
that is needed. The tire cannot penetrate the fluid and the tire rolls on top of the film. This can occur at a much lower speed than dynamic
hydroplaning, but requires a smooth or smooth acting surface, such as asphalt or a touchdown area coated with the accumulated rubber
from previous landings. Such a surface can have the same friction coefficient as wet ice.
When confronted with the possibility of hydroplaning, it is best to land on a grooved runway (if available). Touchdown speed should be
as slow as possible consistent with safety. After the nose-wheel is lowered to the runway, moderate braking is applied. If deceleration is
not detected and hydroplaning is suspected, raise the nose and use aerodynamic drag to decelerate to a point where the brakes become
effective.
Proper braking technique is essential. The brakes are applied firmly until reaching a point just short of a skid. At the first sign of a skid,
release brake pressure and allow the wheels to spin up. Directional control is maintained as far as possible with the rudder. Remember
that in a crosswind, if hydroplaning occurs, the crosswind causes the airplane to simultaneously weathervane into the wind, as well as
slide downwind.
Chapter Summary
Accident statistics show that a pilot is more at risk during the approach and landing than during any other phase of a flight. There are
many factors that contribute to accidents in this phase, but an overwhelming percentage of these accidents result from a lack of pilot
proficiency. This chapter presents procedures that, when learned and practiced correctly, are key to attaining proficiency. Additional
information on aerodynamics, aircraft performance, and other aspects affecting approaches and landings can be found in the Pilot’s
Handbook of Aeronautical Knowledge (FAA-H-8083-25, as revised). For information concerning risk assessment as a means of
preventing accidents, refer to the Risk Management Handbook (FAA-H-8083-2, as revised). Both of these publications are available at
www.faa.gov/regulations_policies/handbooks_manuals/aviation/.