faa-h-8083-3a-6of7, FSX, FAA
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Ch 13.qxd 5/7/04 10:04 AM Page 13-1
T
AILWHEEL AIRPLANES
Tailwheel airplanes are often referred to as
conventional gear airplanes. Due to their design and
structure, tailwheel airplanes exhibit operational and
handling characteristics that are different from those of
tricycle gear airplanes. Tailwheel airplanes are not
necessarily more difficult to takeoff, land, and/or taxi
than tricycle gear airplanes; in fact under certain
conditions, they may even handle with less difficulty.
This chapter will focus on the operational differences
that occur during ground operations, takeoffs, and
landings.
L
ANDING GEAR
The main landing gear forms the principal support of
the airplane on the ground. The tailwheel also supports
the airplane, but steering and directional control are its
primary functions. With the tailwheel-type airplane, the
two main struts are attached to the airplane slightly
ahead of the airplane’s center of gravity (CG).
To turn the airplane on the ground, the pilot should
apply rudder in the desired direction of turn and use
whatever power or brake that is necessary to control
the taxi speed. The rudder should be held in the
direction of the turn until just short of the point where
the turn is to be stopped, then the rudder pressure
released or slight opposite pressure applied as needed.
While taxiing, the pilot will have to anticipate the
movements of the airplane and adjust rudder pressure
accordingly. Since the airplane will continue to turn
slightly even as the rudder pressure is being released,
the stopping of the turn must be anticipated and the
rudder pedals neutralized before the desired heading is
reached. In some cases, it may be necessary to apply
opposite rudder to stop the turn, depending on the taxi
speed.
The presence of moderate to strong headwinds and/or a
strong propeller slipstream makes the use of the
elevator necessary to maintain control of the pitch
attitude while taxiing. This becomes apparent when
considering the lifting action that may be created on
the horizontal tail surfaces by either of those two
factors. The elevator control should be held in the aft
position (stick or yoke back) to hold the tail down.
The rudder pedals are the primary directional controls
while taxiing. Steering with the pedals may be
accomplished through the forces of airflow or propeller
slipstream acting on the rudder surface, or through a
mechanical linkage to the steerable tailwheel. Initially,
the pilot should taxi with the heels of the feet resting on
the cockpit floor and the balls of the feet on the bottom
of the rudder pedals. The feet should be slid up onto the
brake pedals only when it is necessary to depress the
brakes. This permits the simultaneous application of
rudder and brake whenever needed. Some models of
tailwheel airplanes are equipped with heel brakes rather
than toe brakes. In either configuration the brakes are
used primarily to stop the airplane at a desired point, to
slow the airplane, or as an aid in making a sharp
controlled turn. Whenever used, they must be applied
smoothly, evenly, and cautiously at all times.
T
AXIING
When beginning to taxi, the brakes should be tested
immediately for proper operation. This is done by first
applying power to start the airplane moving slowly
forward, then retarding the throttle and simultaneously
applying pressure smoothly to both brakes. If braking
action is unsatisfactory, the engine should be shut down
immediately.
When taxiing in a quartering headwind, the wing on
the upwind side will usually tend to be lifted by the
wind unless the aileron control is held in that direction
(upwind aileron UP). Moving the aileron into the UP
position reduces the effect of wind striking that wing,
thus reducing the lifting action. This control movement
will also cause the opposite aileron to be placed in the
DOWN position, thus creating drag and possibly some
lift on the downwind wing, further reducing the
tendency of the upwind wing to rise.
When taxiing with a quartering tailwind, the elevator
should be held in the full DOWN position (stick or
yoke full forward), and the upwind aileron down. Since
the wind is striking the airplane from behind, these
control positions reduce the tendency of the wind to get
under the tail and the wing possibly causing the
airplane to nose over. The application of these
crosswind taxi corrections also helps to minimize the
weathervaning tendency and ultimately results in
increased controllability.
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An airplane with a tailwheel has a tendency to
weathervane or turn into the wind while it is being
taxied. The tendency of the airplane to weathervane is
greatest while taxiing directly crosswind;
consequently, directional control is somewhat difficult.
Without brakes, it is almost impossible to keep the
airplane from turning into any wind of considerable
velocity since the airplane’s rudder control capability
may be inadequate to counteract the crosswind. In
taxiing downwind, the tendency to weathervane is
increased, due to the tailwind decreasing the
effectiveness of the flight controls. This requires a
more positive use of the rudder and the brakes,
particularly if the wind velocity is above that of a light
breeze.
releasing the brakes, the throttle should be smoothly
and continuously advanced to takeoff power. As the
airplane starts to roll forward, the pilot should slide
both feet down on the rudder pedals so that the toes or
balls of the feet are on the rudder portions, not on the
brake portions.
An abrupt application of power may cause the airplane
to yaw sharply to the left because of the torque effects
of the engine and propeller. Also, precession will be
particularly noticeable during takeoff in a tailwheel-
type airplane if the tail is rapidly raised from a three
point to a level flight attitude. The abrupt change of
attitude tilts the horizontal axis of the propeller, and
the resulting precession produces a forward force on
the right side (90° ahead in the direction of rotation),
yawing the airplane’s nose to the left. The amount of
force created by this precession is directly related to
the rate the propeller axis is tilted when the tail is
raised. With this in mind, the throttle should always be
advanced smoothly and continuously to prevent any
sudden swerving.
Unless the field is soft, or very rough, it is best when
taxiing downwind to hold the elevator control in the
forward position. Even on soft fields, the elevator
should be raised only as much as is absolutely
necessary to maintain a safe margin of control in case
there is a tendency of the airplane to nose over.
On most tailwheel-type airplanes, directional control
while taxiing is facilitated by the use of a steerable
tailwheel, which operates along with the rudder. The
tailwheel steering mechanism remains engaged when
the tailwheel is operated through an arc of about 16 to
18° each side of neutral and then automatically
becomes full swiveling when turned to a greater angle.
On some models the tailwheel may also be locked in
place. The airplane may be pivoted within its own
length, if desired, yet is fully steerable for slight turns
while taxiing forward. While taxiing, the steerable
tailwheel should be used for making normal turns and
the pilot’s feet kept off the brake pedals to avoid
unnecessary wear on the brakes.
Smooth, gradual advancement of the throttle is very
important in tailwheel-type airplanes, since
peculiarities in their takeoff characteristics are
accentuated in proportion to how rapidly the takeoff
power is applied.
As speed is gained, the elevator control will tend to
assume a neutral position if the airplane is correctly
trimmed. At the same time, directional control should
be maintained with smooth, prompt, positive rudder
corrections throughout the takeoff roll. The effects of
torque and P-factor at the initial speeds tend to pull the
nose to the left. The pilot must use what rudder
pressure is needed to correct for these effects or for
existing wind conditions to keep the nose of the
airplane headed straight down the runway. The use of
brakes for steering purposes should be avoided, since
they will cause slower acceleration of the airplane’s
speed, lengthen the takeoff distance, and possibly
result in severe swerving.
Since a tailwheel-type airplane rests on the tailwheel
as well as the main landing wheels, it assumes a
nose-high attitude when on the ground. In most cases
this places the engine cowling high enough to restrict
the pilot’s vision of the area directly ahead of the
airplane. Consequently, objects directly ahead of the
airplane are difficult, if not impossible, to see. To
observe and avoid colliding with any objects or
hazardous surface conditions, the pilot should
alternately turn the nose from one side to the
other—that is zigzag, or make a series of short S-turns
while taxiing forward. This should be done slowly,
smoothly, positively, and cautiously.
When the elevator trim is set for takeoff, on
application of maximum allowable power, the airplane
will (when sufficient speed has been attained)
normally assume the correct takeoff pitch attitude on
its own—the tail will rise slightly. This attitude can
then be maintained by applying slight back-elevator
pressure. If the elevator control is pushed forward
during the takeoff roll to prematurely raise the tail, its
effectiveness will rapidly build up as the speed
increases, making it necessary to apply back-elevator
pressure to lower the tail to the proper takeoff attitude.
This erratic change in attitude will delay the takeoff
and lead to directional control problems. Rudder
pressure must be used promptly and smoothly to
N
ORMAL TAKEOFF ROLL
After taxiing onto the runway, the airplane should be
carefully aligned with the intended takeoff direction,
and the tailwheel positioned straight, or centered. In
airplanes equipped with a locking device, the tailwheel
should be locked in the centered position. After
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counteract yawing forces so that the airplane continues
straight down the runway.
the proper pitch attitude. During takeoffs in strong,
gusty wind, it is advisable that an extra margin of speed
be obtained before the airplane is allowed to leave the
ground. A takeoff at the normal takeoff speed may
result in a lack of positive control, or a stall, when the
airplane encounters a sudden lull in strong, gusty wind,
or other turbulent air currents. In this case, the pilot
should hold the airplane on the ground longer to attain
more speed, then make a smooth, positive rotation to
leave the ground.
While the speed of the takeoff roll increases, more and
more pressure will be felt on the flight controls,
particularly the elevators and rudder. Since the tail
surfaces receive the full effect of the propeller
slipstream, they become effective first. As the speed
continues to increase, all of the flight controls will
gradually become effective enough to maneuver the
airplane about its three axes. It is at this point, in the
taxi to flight transition, that the airplane is being flown
more than taxied. As this occurs, progressively smaller
rudder deflections are needed to maintain direction.
C
ROSSWIND TAKEOFF
It is important to establish and maintain the proper
amount of crosswind correction prior to lift-off; that is,
apply aileron pressure toward the wind to keep the
upwind wing from rising and apply rudder pressure as
needed to prevent weathervaning.
T
AKEOFF
Since a good takeoff depends on the proper takeoff
attitude, it is important to know how this attitude
appears and how it is attained. The ideal takeoff
attitude requires only minimum pitch adjustments
shortly after the airplane lifts off to attain the speed for
the best rate of climb.
As the tailwheel is raised off the runway, the holding
of aileron control into the wind may result in the
downwind wing rising and the downwind main wheel
lifting off the runway first, with the remainder of the
takeoff roll being made on one main wheel. This is
acceptable and is preferable to side-skipping.
The tail should first be allowed to rise off the ground
slightly to permit the airplane to accelerate more
rapidly. At this point, the position of the nose in
relation to the horizon should be noted, then elevator
pressure applied as necessary to hold this attitude. The
wings are kept level by applying aileron pressure as
necessary.
If a significant crosswind exists, the main wheels
should be held on the ground slightly longer than in a
normal takeoff so that a smooth but definite lift-off can
be made. This procedure will allow the airplane to
leave the ground under more positive control so that it
will definitely remain airborne while the proper
amount of drift correction is being established. More
importantly, it will avoid imposing excessive side
loads on the landing gear and prevent possible damage
that would result from the airplane settling back to the
runway while drifting.
The airplane may be allowed to fly off the ground
while in normal takeoff attitude. Forcing it into the air
by applying excessive back-elevator pressure would
result in an excessively high pitch attitude and may
delay the takeoff. As discussed earlier, excessive and
rapid changes in pitch attitude result in proportionate
changes in the effects of torque, making the airplane
more difficult to control.
As both main wheels leave the runway, and ground
friction no longer resists drifting, the airplane will be
slowly carried sideways with the wind until adequate
drift correction is maintained.
Although the airplane can be forced into the air, this is
considered an unsafe practice and should be avoided
under normal circumstances. If the airplane is forced
to leave the ground by using too much back-elevator
pressure before adequate flying speed is attained, the
wing’s angle of attack may be excessive, causing the
airplane to settle back to the runway or even to stall.
On the other hand, if sufficient back-elevator pressure
is not held to maintain the correct takeoff attitude after
becoming airborne, or the nose is allowed to lower
excessively, the airplane may also settle back to the
runway. This occurs because the angle of attack is
decreased and lift is diminished to the degree where it
will not support the airplane. It is important to hold the
attitude constant after rotation or lift-off.
S
HORT-FIELD TAKEOFF
Wing flaps should be lowered prior to takeoff if
recommended by the manufacturer. Takeoff power
should be applied smoothly and continuously, (there
should be no hesitation) to accelerate the airplane as
rapidly as possible. As the takeoff roll progresses, the
airplane’s pitch attitude and angle of attack should be
adjusted to that which results in the minimum amount
of drag and the quickest acceleration. The tail should
be allowed to rise off the ground slightly, then held in
this tail-low flight attitude until the proper lift-off or
rotation airspeed is attained. For the steepest climb-out
and best obstacle clearance, the airplane should be
allowed to roll with its full weight on the main wheels
and accelerated to the lift-off speed.
As the airplane leaves the ground, the pilot must
continue to maintain straight flight, as well as holding
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S
OFT-FIELD TAKEOFF
Wing flaps may be lowered prior to starting the takeoff
(if recommended by the manufacturer) to provide
additional lift and transfer the airplane’s weight from
the wheels to the wings as early as possible. The
airplane should be taxied onto the takeoff surface
without stopping on a soft surface. Stopping on a soft
surface, such as mud or snow, might bog the
airplane down. The airplane should be kept in
continuous motion with sufficient power while lining
up for the takeoff roll.
When the wheels make contact with the ground, the
elevator control should be carefully eased fully back
to hold the tail down and to keep the tailwheel on the
ground. This provides more positive directional
control of the airplane equipped with a steerable
tailwheel, and prevents any tendency for the airplane
to nose over. If the tailwheel is not on the ground,
easing back on the elevator control may cause the
airplane to become airborne again because the change
in attitude will increase the angle of attack and
produce enough lift for the airplane to fly.
As the airplane is aligned with the proposed takeoff
path, takeoff power is applied smoothly and as rapidly
as the powerplant will accept it without faltering. The
tail should be kept low to maintain the inherent
positive angle of attack and to avoid any tendency of
the airplane to nose over as a result of soft spots, tall
grass, or deep snow.
It is extremely important that the touchdown occur
with the airplane’s longitudinal axis exactly parallel to
the direction the airplane is moving along the runway.
Failure to accomplish this not only imposes severe
side loads on the landing gear, but imparts
groundlooping (swerving) tendencies. To avoid these
side stresses or a ground loop, the pilot must never
allow the airplane to touch down while in a crab or
while drifting.
When the airplane is held at a nose-high attitude
throughout the takeoff run, the wings will, as speed
increases and lift develops, progressively relieve the
wheels of more and more of the airplane’s weight,
thereby minimizing the drag caused by surface
irregularities or adhesion. If this attitude is accurately
maintained, the airplane will virtually fly itself off the
ground. The airplane should be allowed to accelerate
to climb speed in ground effect.
T
OUCHDOWN
The touchdown is the gentle settling of the airplane
onto the landing surface. The roundout and touchdown
should be made with the engine idling, and the airplane
at minimum controllable airspeed, so that the airplane
will touch down at approximately stalling speed. As
the airplane settles, the proper landing attitude must be
attained by applying whatever back-elevator pressure
is necessary. The roundout and touchdown should be
timed so that the wheels of the main landing gear and
tailwheel touch down simultaneously (three-point
landing). This requires proper timing, technique, and
judgment of distance and altitude. [Figure 13-1]
A
FTER-LANDING ROLL
The landing process must never be considered
complete until the airplane decelerates to the normal
taxi speed during the landing roll or has been brought
to a complete stop when clear of the landing area. The
pilot must be alert for directional control difficulties
immediately upon and after touchdown due to the
ground friction on the wheels. The friction creates a
pivot point on which a moment arm can act. This is
because the CG is behind the main wheels.
[Figure 13-2]
Any difference between the direction the airplane is
traveling and the direction it is headed will produce a
moment about the pivot point of the wheels, and the
airplane will tend to swerve. Loss of directional
control may lead to an aggravated, uncontrolled, tight
turn on the ground, or a ground loop. The combination
of inertia acting on the CG and ground friction of the
main wheels resisting it during the ground loop may
cause the airplane to tip or lean enough for the outside
Normal
Glide
Start Roundout
to Landing Attitude
Main Gear and Tailwheel
To uch Down Simultaneously
Hold Elevator
Full Up
Figure 13-1. Tailwheel touchdown.
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Point of
Wheel Pivoting
the friction and drag of the wheels on the ground.
Brakes may be used if needed to help slow the airplane.
After the airplane has been slowed sufficiently and has
been turned onto a taxiway or clear of the landing area,
it should be brought to a complete stop. Only after this
is done should the pilot retract the flaps and perform
other checklist items.
C.G.
C
ROSSWIND LANDING
If the crab method of drift correction has been used
throughout the final approach and roundout, the crab
must be removed before touchdown by applying
rudder to align the airplane’s longitudinal axis with its
direction of movement. This requires timely and
accurate action. Failure to accomplish this results in
severe side loads being imposed on the landing gear
and imparts ground looping tendencies.
Figure 13-2. Effect of CG on directional control.
wingtip to contact the ground, and may even impose a
sideward force that could collapse the landing gear.
The airplane can ground loop late in the after-landing
roll because rudder effectiveness decreases with the
decreasing flow of air along the rudder surface as the
airplane slows. As the airplane speed decreases and the
tailwheel has been lowered to the ground, the steerable
tailwheel provides more positive directional control.
If the wing-low method is used, the crosswind
correction (aileron into the wind and opposite rudder)
should be maintained throughout the roundout, and the
touchdown made on the upwind main wheel.
During gusty or high-wind conditions, prompt
adjustments must be made in the crosswind correction
to assure that the airplane does not drift as it touches
down.
To use the brakes, the pilot should slide the toes or feet
up from the rudder pedals to the brake pedals (or apply
heel pressure in airplanes equipped with heel brakes).
If rudder pressure is being held at the time braking
action is needed, that pressure should not be released
as the feet or toes are being slid up to the brake pedals,
because control may be lost before brakes can be
applied. During the ground roll, the airplane’s
direction of movement may be changed by carefully
applying pressure on one brake or uneven pressures on
each brake in the desired direction. Caution must be
exercised, when applying brakes to avoid
overcontrolling.
As the forward speed decreases after initial contact,
the weight of the airplane will cause the downwind
main wheel to gradually settle onto the runway.
An adequate amount of power should be used to
maintain the proper airspeed throughout the approach,
and the throttle should be retarded to idling position
after the main wheels contact the landing surface. Care
must be exercised in closing the throttle before the
pilot is ready for touchdown, because the sudden or
premature closing of the throttle may cause a sudden
increase in the descent rate that could result in a hard
landing.
If a wing starts to rise, aileron control should be
applied toward that wing to lower it. The amount
required will depend on speed because as the forward
speed of the airplane decreases, the ailerons will
become less effective.
C
ROSSWIND AFTER-LANDING ROLL
Particularly during the after-landing roll, special
attention must be given to maintaining directional
control by the use of rudder and tailwheel steering,
while keeping the upwind wing from rising by the use
of aileron. Characteristically, an airplane has a greater
profile, or side area, behind the main landing gear than
forward of it. [Figure 13-3] With the main wheels
acting as a pivot point and the greater surface area
exposed to the crosswind behind that pivot point, the
airplane will tend to turn or weathervane into the wind.
This weathervaning tendency is more prevalent in the
tailwheel-type because the airplane’s surface area
behind the main landing gear is greater than in
nosewheel-type airplanes.
The elevator control should be held back as far as
possible and as firmly as possible, until the airplane
stops. This provides more positive control with
tailwheel steering, tends to shorten the after-landing
roll, and prevents bouncing and skipping.
If available runway permits, the speed of the airplane
should be allowed to dissipate in a normal manner by
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