4. Reducing throttle rapidly in situations in which
proper rpm has been exceeded, usually resulting in
exaggerated heading changes and loss of lift, resulting
in loss of altitude.
5. Failing to ascend slowly.
Hovering
A stationary hover is a maneuver in which the helicopter is
main tained in nearly motionless flight over a reference point
at a constant altitude and on a constant heading.
Technique
To maintain a hover over a point, use sideview and peripheral
vision to look for small changes in the helicopter’s attitude
and altitude. When these changes are noted, make the
necessary con trol inputs before the helicopter starts to
move from the point. To detect small variations in altitude
or position, the main area of visual attention needs to be
some distance from the aircraft, using various points on the
helicopter or the tip-path plane as a reference. Looking too
closely or looking down leads to overcontrolling. Obviously,
in order to remain over a certain point, know where the point
is, but do not focus all attention there.
As with a takeoff, the pilot controls altitude with the collec-
tive and maintains a constant rpm with the throttle. The cyclic
is used to maintain the helicopter’s position; the pedals, to
control heading. To maintain the helicopter in a stabilized
hover, make small, smooth, coordinated corrections. As the
desired effect occurs, remove the correction in order to stop the
helicopter’s movement. For example, if the helicopter begins
to move rearward, apply a small amount of forward cyclic
pressure. However, neutralize this pres sure just before the
helicopter comes to a stop, or it will begin to move forward.
After experience is gained, a pilot develops a certain “feel”
for the helicopter. Small deviations can be felt and seen,
so you can make the corrections before the helicopter
actually moves. A certain relaxed looseness develops, and
controlling the helicopter becomes sec ond nature, rather than
a mechanical response.
Common Errors
1. Tenseness and slow reactions to movements of the
helicopter.
2. Failure to allow for lag in cyclic and collective pitch,
which leads to overcontrolling. It is very common for
a student to get ahead of the helicopter. Due to inertia,
it requires some small time period for the helicopter
to respond.
3. Confusing attitude changes for altitude changes, which
results in improper use of the controls.
4. Hovering too high, creating a hazardous flight
condition. The height velocity chart should be
referenced to determine the maximum skid height
to hover and safely recover the helicopter should a
malfunction occur.
5. Hovering too low, resulting in occasional touch down.
6. Becoming overly confident over prepared surfaces
when taking off to a hover. Be aware that dynamic
rollover accidents usually occur over a level surface.
Hovering Turn
A hovering turn is a maneuver performed at hovering height
in which the nose of the helicopter is rotated either left or
right while maintaining position over a reference point on the
surface. Hovering turns can also be made around the mast or
tail of the aircraft. The maneuver requires the coordination
of all flight controls and demands pre cise control near the
surface. A pilot should maintain a constant altitude, rate of
turn, and rpm.
Technique
Initiate the turn in either direction by applying anti-torque
pedal pressure toward the desired direction. It should be noted
that during a turn to the left, more power is required because
left pedal pressure increases the pitch angle of the tail rotor,
which, in turn, requires additional power from the engine. A
turn to the right requires less power. (On helicopters with a
clock wise rotating main rotor, right pedal increases the pitch
angle and, therefore, requires more power.)
As the turn begins, use the cyclic as necessary (usually into
the wind) to keep the helicopter over the desired spot. To
continue the turn, add more pedal pressure as the helicopter
turns to the cross wind position. This is because the wind is
striking the tail surface and tail rotor area, making it more
difficult for the tail to turn into the wind. As pedal pressures
increase due to crosswind forces, increase the cyclic pressure
into the wind to maintain position. Use the collective with the
throttle to maintain a constant altitude and rpm. [Figure 9-6]
After the 90° portion of the turn, decrease pedal pressure
slightly to maintain the same rate of turn. Approaching the
180°, or downwind portion, anticipate opposite pedal pressure
due to the tail moving from an upwind position to a down-
wind position. At this point, the rate of turn has a ten dency
to increase at a rapid rate due to the tendency of the tail
surfaces to weathervane. Because of the tailwind condition,
Pedal
Some left in hover, more
left to start turn to left
Collective
Adjust collective as
necessary to maintain
proper hover height
Throttle
As necessary to
maintain rpm
Normally left pedal
application requires
more throttle
Pedal
Most left pressure in
turn
Collective
Adjust collective as
necessary to maintain
proper hover height
Throttle
As necessary to
maintain rpm
Normally left pedal
application requires
more throttle
Pedal
Changing from left to
right pressure
Collective
Adjust collective as
necessary to maintain
proper hover height
Throttle
As necessary to
maintain rpm
Normally left pedal
application requires
more throttle
Pedal
Most right pedal
pressure in turn
Collective
Adjust collective as
necessary to maintain
proper hover height
Throttle
As necessary to
maintain rpm
Pedal
Some right to stop turn,
then left to maintain
heading
Collective
Adjust collective as
necessary to maintain
proper hover height
Throttle
As necessary to
maintain rpm
Normally left pedal
application requires
more throttle
Cyclic—Forward Cyclic—Right Cyclic—Rearward Cyclic—Left Cyclic—Forward
WIND
WIND
Figure 9-6. Left turns in helicopters with a counterclockwise rotating main rotor are more difficult to execute because the tail rotor
demands more power. This requires you to compensate with additional left pedal and increased throttle. Refer to this graphic throughout
the remainder of the discussion on a hovering turn to the left.
hold rearward cyclic pressure to keep the helicopter over
the same spot.
The horizontal stabilizer has a tendency to lift the tail during
a tailwind condition. This is the most difficult portion of
the hovering turn. Horizontal and vertical stabilizers have
several different designs and locations, including the canted
stabilizers used on some Hughes and Schweizer helicopters.
The primary purpose of the vertical stabilizer is to unload
the work of the antitorque system and to aid in trimming the
helicopter in flight should the antitorque system fail. The
horizontal stabilizer provides for a more usable CG range
and aids in trimming the helicopter longitudinally.
Because of the helicopter’s tendency to weathervane,
maintaining the same rate of turn from the 180° posi tion
actually requires some pedal pressure opposite the direction
of turn. If a pilot does not apply opposite pedal pressure,
the helicopter tends to turn at a faster rate. The amount of
pedal pressure and cyclic deflection throughout the turn
depends on the wind velocity. As the turn is finished on the
upwind heading, apply opposite pedal pressure to stop the
turn. Gradually apply forward cyclic pressure to keep the
helicopter from drifting.
Control pressures and direction of application change
continuously throughout the turn. The most dramatic change
is the pedal pressure (and corresponding power requirement)
necessary to control the rate of turn as the helicopter moves
through the downwind portion of the maneuver.
Turns can be made in either direction; however, in a high
wind condition, the tail rotor may not be able to produce
enough thrust, which means the pilot cannot control a turn
to the right in a counterclockwise rotor system. Therefore,
if control is ever question able, first attempt to make a 90°
turn to the left. If sufficient tail rotor thrust exists to turn
the helicopter crosswind in a left turn, a right turn can be
successfully controlled. The opposite applies to helicopters
with clockwise rotor systems. In this case, start the turn to
the right. Hovering turns should be avoided in winds strong
enough to preclude sufficient aft cyclic control to maintain
the helicopter on the selected surface reference point
when headed downwind. Check the flight manual for the
manufacturer’s recom mendations for this limitation.
A O M
CLUTCH MR
TEMP
MR
CHIP
STARTER
ON
TR
CHIP
lOW
FUEL
LOW
RPM
26 26
FUEL
245 II5
OBS
21 15
NAV
GS
VERTICAL SPEED
100 FEET PER MINUTE
UP
DOWN
2I
I2 6
2 MIN TURN
DC ELEC
L R
30.0
29.929.8
I00 FEET
CALIBRATED
TO
20,000 FEET
ALT
20 20
I0 I0
I0 I0
20 20
TESTSTBY PWR
IN Hg
ALg.
MANFOLD
PRESS
20 30
0 10
MPH
KNOTS
90 80 70
E R
%RPM
Reference point
Figure 9-7. To maintain a straight ground track, use two reference
points in line and at some distance in front of the helicopter.
Reference point
Figure 9-8. The key to hovering sideward is establishing at least
two reference points that help maintain a straight track over the
ground while keeping a constant heading.
2. Failure to use proper antitorque pedal control, resulting
in excessive heading change.
3. Failure to maintain desired hovering height.
4. Failure to maintain proper rpm.
5. Failure to maintain alignment with direction of travel.
Hovering—Sideward Flight
Sideward hovering flight may be necessary to move the
helicopter to a specific area when conditions make it
impossible to use forward flight. During the maneu ver,
a constant groundspeed, altitude, and heading should be
maintained.
Technique
Before starting sideward hovering flight, ensure the area
for the hover is clear, especially at the tail rotor. Constantly
monitor hover height and tail rotor clearance during all
hovering maneuvers to prevent dynamic rollover or tail
rotor strikes to the ground. Then, pick two points of in-line
reference in the direction of sideward hovering flight to help
maintain the proper ground track. These reference points
should be kept in line throughout the maneuver. [Figure 9-8]
Begin the maneuver from a normal hovering height by
applying cyclic toward the side in which the movement is
desired. As the movement begins, return the cyclic toward the
neutral position to maintain low groundspeed—no faster than
a brisk walk. Throughout the maneuver, maintain a constant
groundspeed and ground track with cyclic. Maintain heading,
Common Errors
1. Failing to maintain a slow, constant rate of turn.
2. Failing to maintain position over the reference point.
3. Failing to maintain rpm within normal range.
4. Failing to maintain constant altitude.
5. Failing to use the antitorque pedals properly.
Hovering—Forward Flight
Forward hovering flight is normally used to move a helicopter
to a specific location, and it may begin from a stationary
hover. During the maneuver, constant groundspeed, altitude,
and heading should be maintained.
Technique
Before starting, pick out two references directly in front and
in line with the helicopter. These reference points should be
kept in line throughout the maneuver. [Figure 9-7]
Begin the maneuver from a normal hovering height by
applying forward pressure on the cyclic. As movement
begins, return the cyclic toward the neutral position to
maintain low groundspeed—no faster than a brisk walk.
Throughout the maneuver, maintain a constant groundspeed
and path over the ground with the cyclic, a constant heading
with the antitorque pedals, altitude with the collective, and
the proper rpm with the throttle.
To stop the forward movement, apply rearward cyclic
pressure until the helicopter stops. As forward motion stops,
return the cyclic to the neutral position to pre vent rearward
movement. Forward movement can also be stopped by
simply applying rearward pressure to level the helicopter
and allowing it to drift to a stop.
Common Errors
1. Exaggerated movement of the cyclic, resulting in
erratic movement over the surface.
Hover taxi (25 feet or less)
Poor surface conditions for skid type helicopters
Figure 9-9. Hover taxi.
which in this maneuver is perpendicular to the ground track,
with the antitorque pedals, and a constant altitude with the
collective. Use the throttle to maintain the proper operating
rpm. Be aware that the nose tends to weathervane into the
wind. Changes in the pedal position will change the rpm
and must be corrected by collective and/or throttle changes
to maintain altitude.
To stop the sideward movement, apply cyclic pres sure in
the direction opposite to that of movement and hold it until
the helicopter stops. As motion stops, return the cyclic to
the neutral position to prevent movement in the opposite
direction. Applying sufficient opposite cyclic pressure to
level the helicopter may also stop sideward move ment. The
helicopter then drifts to a stop.
Common Errors
1. Exaggerated movement of the cyclic, resulting in
overcontrolling and erratic movement over the surface.
2. Failure to use proper antitorque pedal control, resulting
in excessive heading change.
3. Failure to maintain desired hovering height.
4. Failure to maintain proper rpm.
5. Failure to make sure the area is clear prior to starting
the maneuver.
Hovering—Rearward Flight
Rearward hovering flight may be necessary to move the
helicopter to a specific area when the situation is such that
forward or sideward hovering flight cannot be used. During
the maneuver, maintain a constant groundspeed, altitude, and
heading. Due to the limited visibility behind a helicopter, it
is important that the area behind the helicopter be cleared
before beginning the maneuver. Use of ground personnel is
rec ommended.
Technique
Before starting rearward hovering flight, pick out two
reference points in front of, and in line with the heli copter
just like hovering for ward. [Figure 9-7] The movement of
the helicopter should be such that these points remain in line.
Begin the maneuver from a normal hovering height
by applying rearward pressure on the cyclic. After the
movement has begun, position the cyclic to maintain a slow
groundspeed—no faster than a brisk walk. Throughout the
maneuver, maintain constant ground speed and ground track
with the cyclic, a constant heading with the antitorque pedals,
constant altitude with the collective, and the proper rpm with
the throttle.
To stop the rearward movement, apply forward cyclic and
hold it until the helicopter stops. As the motion stops, return
the cyclic to the neutral position. Also, as in the case of
forward and sideward hovering flight, opposite cyclic can
be used to level the helicopter and let it drift to a stop. Tail
rotor clearance must be maintained. Generally, a higher-than-
normal hover altitude is preferred.
Common Errors
1. Exaggerated movement of the cyclic resulting in
overcontrolling and an uneven movement over the
surface.
2. Failure to use proper antitorque pedal control, resulting
in excessive heading change.
3. Failure to maintain desired hovering height.
4. Failure to maintain proper rpm.
5. Failure to make sure the area is clear prior to starting
the maneuver.
Taxiing
Taxiing refers to operations on or near the surface of taxiways
or other prescribed routes. Helicopters utilize three different
types of taxiing.
Hover Taxi
A hover taxi is used when operating below 25 feet above
ground level (AGL). [Figure 9-9] Since hover taxi is just like
forward, sideward, or rearward hovering flight, the technique
to perform it is not presented here.
Air Taxi
An air taxi is preferred when movements require greater
distances within an airport or heliport bound ary. [Figure 9-10]
In this case, fly to the new location; however, it is expected
that the helicopter will remain below 100 feet AGL with
an appropriate airspeed and will avoid over flight of other
aircraft, vehicles, and personnel.
Air taxi (100 feet or less)
Faster travel
Figure 9-10. Air taxi.
Surface taxi
Less rotor downwash
Figure 9-11. Surface taxi.
Technique
Before starting, determine the appropriate airspeed and
altitude combination to remain out of the cross-hatched or
shaded areas of the height/velocity diagram (see Figure 7-1).
Additionally, be aware of crosswind conditions that could
lead to loss of tail rotor effectiveness. Pick out two references
directly in front of the helicopter for the ground path desired.
These reference points should be kept in line throughout the
maneuver.
Begin the maneuver from a normal hovering height by
applying forward pressure on the cyclic. As move ment
begins, attain the desired airspeed with the cyclic. Control the
desired altitude with the collective and rpm with the throttle.
Throughout the maneuver, maintain a desired groundspeed
and ground track with the cyclic, a constant heading with
antitorque pedals, the desired altitude with the collective,
and proper operating rpm with the throttle.
To stop the forward movement, apply aft cyclic pressure to
reduce forward speed. Simultaneously lower the col lective to
initiate a descent to hover altitude. As forward motion stops,
return the cyclic to the neutral posi tion to prevent rearward
movement. As approaching the proper hover altitude, increase
the collective as necessary to stop descent at hover altitude
(much like a quick stop maneuver (see page 10-4)).
Common Errors
1. Erratic movement of the cyclic, resulting in improper
airspeed control and erratic movement over the
surface.
2. Failure to use proper antitorque pedal control, result ing
in excessive heading change.
3. Failure to maintain desired altitude.
4. Failure to maintain proper rpm.
5. Overflying parked aircraft causing possible dam age
from rotor downwash.
6. Flying in the cross-hatched or shaded area of the
height/velocity diagram.
7. Flying in a crosswind that could lead to loss of tail
rotor effectiveness.
8. Excessive tail-low attitudes.
9. Excessive power used or required to stop.
10. Failure to maintain alignment with direction of travel.
Surface Taxi
A surface taxi is used to minimize the effects of rotor
downwash in wheel-type helicopters. [Figure 9-11] Surface
taxiing in skid type helicopters is generally not recommended
due to the high risk of dynamic rollover; for more information,
refer to Chapter 11, Helicopter Emergencies and Hazards.
Technique
The helicopter should be in a stationary position on the surface
with the collective full down and the rpm the same as that
used for a hover. This rpm should be maintained throughout
the maneuver. Then, move the cyclic slightly forward and
apply gradual upward pres sure on the collective to move
the helicopter forward along the surface. Use the antitorque
pedals to maintain heading and the cyclic to maintain ground
track. The collective controls starting, stopping, and speed
while taxiing. The higher the collective pitch, the faster the
taxi speed; however, do not taxi faster than a brisk walk. If
the helicopter is equipped with brakes, use them to help slow
down. Do not use the cyclic to control groundspeed.
During a crosswind taxi, hold the cyclic into the wind a
sufficient amount to eliminate any drifting movement.
Common Errors
1. Improper use of cyclic.
2. Failure to use antitorque pedals for heading control.
1 2
Figure 9-12. The helicopter takes several positions during a normal takeoff from hover.
3. Improper use of the controls during crosswind
operations.
4. Failure to maintain proper rpm.
Normal Takeoff from a Hover
A normal takeoff from a hover is an orderly transition to
forward flight and is executed to increase altitude safely and
expeditiously. Before initiating a takeoff, the pilot should
ensure that the proper checklist has been completed and
the helicopter systems are within normal limits. During the
takeoff, fly a pro file that avoids the cross-hatched or shaded
areas of the height/velocity diagram.
Technique
Refer to Figure 9-12 (position 1). Bring the helicopter to a
hover and perform a hover and systems check, which includes
power, balance, and flight controls prior to continuing flight.
The power check should include an evaluation of the amount
of excess power available; that is, the difference between the
power being used to hover and the power available at the
existing altitude and temperature conditions. The balance
condition of the helicopter is indicated by the position
of the cyclic when maintaining a stationary hover. Wind
necessitates some cyclic deflection, but there should not be
an extreme deviation from neutral. Flight controls must move
freely, and the hel icopter should respond normally. Then,
visually clear the surrounding area.
Start the helicopter moving by smoothly and slowly eas ing the
cyclic forward (position 2). As the helicopter starts to move
forward, increase the collective, as nec essary, to prevent the
helicopter from sinking and adjust the throttle to maintain
rpm. The increase in power requires an increase in the proper
antitorque pedal to maintain heading. Maintain a straight
takeoff path throughout the takeoff.
While accelerating through effec tive translational lift (position
3), the helicopter begins to climb, and the nose tends to rise
due to increased lift. At this point, adjust the collective to
obtain normal climb power and apply enough forward cyclic
to overcome the tendency of the nose to rise. At position 4,
hold an attitude that allows a smooth acceleration toward
climb ing airspeed and a commensurate gain in altitude so that
the takeoff profile does not take the helicopter through any
of the cross-hatched or shaded areas of the height/velocity
diagram. As airspeed increases (position 5), place the aircraft
in trim and allow a crab to take place to maintain ground track
and a more favorable climb configuration. As the helicopter
continues to climb and accel erate to best rate-of-climb, apply
aft cyclic pressure to raise the nose smoothly to the normal
climb attitude.
Common Errors
1. Failing to use sufficient collective pitch to pre vent
loss of altitude prior to attaining transla tional lift.
2. Adding power too rapidly at the beginning of the
transition from hovering to forward flight without
forward cyclic compensation, causing the helicopter
to gain excessive altitude before acquiring airspeed.
3. Assuming an extreme nose-down attitude near the
surface in the transition from hovering to forward
flight.
4. Failing to maintain a straight flightpath over the
surface (ground track).
5. Failing to maintain proper airspeed during the climb.
6. Failing to adjust the throttle to maintain proper rpm.
7. Failing to transition to a level crab to maintain ground
track.
Helicopter
side movement Wind movement
Wind Movement
Helicopter HeadingGround Track
Figure 9-13. During a slip, the rotor disk is tilted into the wind.
Figure 9-14. To compensate for wind drift at altitude, crab the
helicopter into the wind.
Normal Takeoff from the Surface
Normal takeoff from the surface is used to move the helicopter
from a position on the surface into effective translational lift
and a normal climb using a minimum amount of power. If the
surface is dusty or covered with loose snow, this technique
provides the most favorable visibility conditions and reduces
the possibility of debris being ingested by the engine.
Technique
Place the helicopter in a stationary position on the sur face.
Lower the collective to the full down position, and reduce
the rpm below operating rpm. Visually clear the area and
select terrain features or other objects to aid in maintaining
the desired track during takeoff and climb out. Increase the
throttle to the proper rpm, and raise the collective slowly
until the helicopter is light on the skids. Hesitate momentarily
and adjust the cyclic and antitorque pedals, as neces sary, to
prevent any surface movement. Continue to apply upward
collective. As the helicopter leaves the ground, use the
cyclic, as necessary, to begin forward movement as altitude
is gained. Continue to acceler ate. As effective translational
lift is attained, the helicopter begins to climb. Adjust attitude
and power, if necessary, to climb in the same manner as a
takeoff from a hover. A second, less efficient, but acceptable,
technique, is to attempt a vertical takeoff to evaluate if power
or lift is sufficient to clear obstructions. This allows the
helicopter to be returned to the takeoff position if required.
Common Errors
1. Departing the surface in an attitude that is too nose-
low. This situation requires the use of exces sive power
to initiate a climb.
2. Using excessive power combined with a level attitude,
which causes a vertical climb, unless needed for
obstructions and landing considerations.
3. Application of the collective that is too abrupt when
departing the surface, causing rpm and heading control
errors.
Crosswind Considerations During Takeoffs
If the takeoff is made during crosswind conditions, the
helicopter is flown in a slip during the early stages of the
maneuver. [Figure 9-13] The cyclic is held into the wind a
sufficient amount to maintain the desired ground track for
the takeoff. The heading is maintained with the use of the
antitorque pedals. In other words, the rotor is tilted into the
wind so that the sideward movement of the helicopter is
just enough to counter act the crosswind effect. To prevent
the nose from turning in the direction of the rotor tilt, it is
necessary to increase the antitorque pedal pressure on the
side opposite the cyclic.
After approximately 50 feet of altitude is gained, make a
coordinated turn into the wind to maintain the desired ground
track. This is called crabbing into the wind. The stronger the
crosswind, the more the helicopter has to be turned into the
wind to maintain the desired ground track. [Figure 9-14]
Ground Reference Maneuvers
Ground reference maneuvers may be used as training
exercises to help develop a division of attention between
the flightpath and ground references, and while controlling
the helicopter and watching for other air craft in the vicinity.
Other examples of ground reference maneuvers are flights
for photographic or observation purposes, such as pipe line
or power line checks. Prior to each maneuver, a clearing turn
should be done to ensure the area is free of conflicting traffic.
Rectangular Course
The rectangular course is a training maneuver in which the
ground track of the helicopter is kept equidistant from the
sides of a selected rectangular area. While performing the
maneuver, the altitude and air speed should be held constant.
The rectangular course helps develop recognition of a drift
toward or away from a line parallel to the intended ground
track. This is helpful in recognizing drift toward or from an
airport runway during the various legs of the airport traffic
pattern and is also useful in observation and photographic
flights.
Technique
Maintaining ground track while trying to fly a straight line
can be very difficult for new pilots to do. It is important to
understand the effects of the wind and how to compensate
for this. For this maneuver, pick a square or rectangular
field, or an area bounded on four sides by section lines or
roads, with sides approximately a mile in length. The area
selected should be well away from other air traffic. Fly the
maneuver approximately 500 to 1,000 feet above the ground
as appropriate. If the student finds it difficult to maintain a
proper ground track at that higher altitude, lower the altitude
for better ground reference until they feel more comfortable
and are able to grasp the concept better. Altitude can be raised
up to 1,000 feet as proficiency improves.
Fly the helicopter parallel to and at a uniform distance, about
one-fourth to one-half mile, from the field boundaries, and
not directly above the boundaries. For best results, position
flightpath outside the field boundaries just far enough away
that they may be easily observed from either pilot seat by
looking out the side of the helicopter. If an attempt is made
to fly directly above the edges of the field, there will be no
usable reference points to start and complete the turns. In
addition, the closer the track of the helicop ter is to the field
boundaries, the steeper the bank necessary at the turning
points. The edges of the selected field should be seen while
seated in a normal position and looking out the side of the
helicopter 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 helicopter is
abeam the corners of the field boundaries. The bank nor mally
should not exceed 30°–45° in light winds. Strong winds may
require more bank.
The pilot should understand that when trying to fly a straight
line and maintain a specific heading, aircraft heading must be
adjusted in order to compensate for the winds and stay on the
proper ground track. Also, keep in mind that a constant scan
of flight instruments and outside references aid in maintaining
proper ground track.
Although the rectangular course may be entered from any
direction, this discussion assumes entry on a downwind
heading. [Figure 9-15] while approaching the field boundary
on the downwind leg, begin planning for an upcoming turn.
Since there is a tailwind on the downwind leg, the helicopter’s
groundspeed is increased (position 1). During the turn, the
wind causes the heli copter to drift away from the field. To
counteract this effect, the roll-in should be made at a fairly
fast rate with a relatively steep bank (position 2). This is
normally the steepest turn of the maneuver.
As the turn progresses, the tailwind component decreases,
which decreases the groundspeed. Consequently, the bank
angle and rate-of-turn must be reduced gradually to ensure
that upon completion of the turn, the crosswind ground track
continues to be the same distance from the edge of the field.
Upon completion of the turn, the helicopter should be level
and crabbed into the wind in order to maintain the proper
ground track. Keep in mind that in order to maintain proper
ground track the helicopter may have to be flown almost
sideways depending on the amount of wind. The forward
cyclic that is applied for airspeed will be in the direction of
the intended flight path. For this example, it will be in the
direction of the downwind corner of the field. However, since
the wind is now pushing the helicopter away from the field,
establish the proper drift correction by heading slightly into
the wind. Therefore, the turn should be greater than a 90°
change in heading (position 3). If the turn has been made
properly, the field boundary again appears to be one-fourth
to one-half mile away. While on the crosswind leg, the wind
correction should be adjusted, as necessary, to maintain a
uniform distance from the field boundary (position 4).
As the next field boundary is being approached (position 5),
plan for the next turn. Since a wind correction angle is being
held into the wind and toward the field, this next turn requires
a turn of less than 90°. Since there is now a headwind, the
groundspeed decreases during the turn, the bank initially must
be medium and progressively decrease as the turn pro ceeds.
To complete the turn, time the rollout so that the helicopter
becomes level at a point aligned with the corner of the field
just as the longitudinal axis of the helicopter again becomes
parallel to the field boundary (position 6). The distance from
the field boundary should be the same as on the other sides
of the field.
Wind
Track with no wind correction
Track with no wind correction
6 7 8
11 Turn more than 90°
Complete turn at boundary
Start turn
at boundary
Crab into wind
Start turn at boundaryNo crabComplete turn at boundary
Start turn
at boundary
Crab into wind
Complete turn at boundary
Start turn at boundary
Turn less than 90°
Enter 45° to downwind
Turn less than 90°—roll out with crab established
Complete turn at boundary
No crab
Turn more than 90°—roll
out with crab established
Figure 9-15. Example of a rectangular course.
Point of steepest bank
Points of steepest bank
Points of shallowest bank
Wind
Figure 9-16. S-turns across a road.
Continue to evaluate each turn and determine the steepness
or shallowness based on the winds. It is also important to
remember that as the bank angles are adjusted in the turn,
the pilot is subsequently forced to make changes with the
flight controls.
Common Errors
1. Faulty entry technique.
2. Poor planning, orientation, and/or division of attention.
3. Uncoordinated flight control application.
4. Improper correction for wind drift.
5. Failure to maintain selected altitude and airspeed.
6. Selection of a ground reference with no suitable
emergency landing area within gliding distance.
7. Not flying a course parallel to the intended area (e.g.,
traffic pattern or square field).
S-Turns
Another training maneuver to use is the S-turn, which helps
correct for wind drift in turns. This maneuver requires turns
to the left and right.
Technique
The pilot can choose to use a road, a fence, or a railroad
for a reference line. Regardless of what is used, it should
be straight for a considerable distance and should extend as
nearly perpendicular to the wind as possible. The object of
S-turns is to fly a pattern of two half cir cles of equal size
on opposite sides of the reference line. [Figure 9-16] The
maneuver should be performed at a constant altitude between
500 and 800 feet above the terrain. As mentioned previously,
if the student pilot is having a difficult time maintaining the
proper altitude and airspeed, have him or her attempt the
S-turn at a lower altitude, providing better ground reference.
The discussion that follows is based on choosing a reference
line perpendicular to the wind and starting the maneuver with
the helicopter facing downwind.
As the helicopter crosses the reference line, immedi-
ately establish a bank. This initial bank is the steepest
used throughout the maneuver since the helicopter is
headed directly downwind and the groundspeed is greatest
(position 1). Gradually reduce the bank, as necessary, to
describe a ground track of a half circle. Time the turn so
that, as the rollout is completed, the helicopter is crossing
the reference line perpendicular to it and head ing directly
upwind (position 2). Immediately enter a bank in the opposite
direction to begin the second half of the “S” (position 3).
Since the helicopter is now on an upwind heading, this bank
(and the one just completed before crossing the reference
line) is the shallowest in the maneuver. Gradually increase
the bank, as necessary, to describe a ground track that is a
half circle identical in size to the one previously completed on
the other side of the refer ence line (position 4). The steepest
bank in this turn should be attained just prior to rollout when
the helicopter is approaching the reference line nearest the
downwind heading. Time the turn so that as the rollout is
com plete, the helicopter is perpendicular to the reference
line and is again heading directly downwind (position 5).
In summary, the angle of bank required at any given
point in the maneuver is dependent on the ground speed.
The faster the groundspeed is, the steeper the bank is; the
slower the groundspeed is, the shallower the bank is. To
express it another way, the more nearly the helicopter is to a
downwind heading, the steeper the bank; the more nearly it
is to an upwind heading, the shallower the bank. In addition
to varying the angle of bank to correct for drift in order to
maintain the proper radius of turn, the helicopter must also
be flown with a drift correction angle (crab) in relation to its
ground track; except, of course, when it is on direct upwind
or downwind headings or there is no wind.
One would normally think of the fore and aft axis of the
heli copter as being tangent to the ground track pattern at
each point. However, this is not the case. During the turn on
the upwind side of the reference line (side from which the
wind is blowing), crab the nose of the heli copter toward the
outside of the circle. During the turn on the downwind side
of the reference line (side of the reference line opposite to the
direction from which the wind is blowing), crab the nose of
the helicopter toward the inside of the circle. In either case, it
is obvious that the helicopter is being crabbed into the wind
just as it is when trying to maintain a straight ground track.
The amount of crab depends on the wind velocity and how
close the helicopter is to a crosswind position. The stronger
the wind is, the greater the crab angle is at any given position
for a turn of a given radius. The more nearly the helicopter
is to a crosswind position, the greater the crab angle. The
maximum crab angle should be at the point of each half circle
farthest from the reference line.
A standard radius for S-turns cannot be specified, since the
radius depends on the airspeed of the helicopter, the velocity
of the wind, and the initial bank chosen for entry. The only
standard is crossing the ground reference line straight and
level and having equal radius semi-circles on both sides.
Common Errors
1. Using antitorque pedal pressures to assist turns.
2. Slipping or skidding in the turn.
3. An unsymmetrical ground track during S-turns across
a road.
4. Improper correction for wind drift.
5. Failure to maintain selected altitude or airspeed.
6. Excessive bank angles.
Turns Around a Point
This training maneuver requires flying constant radius
turns around a preselected point on the ground using a bank
angle of approximately 30°–45°, while maintaining both
a constant altitude and the same distance from the point
throughout the maneuver. [Figure 9-17] The objective, as in
other ground reference maneuvers, is to develop the ability
to subconsciously control the helicopter while dividing
attention between flightpath, how the winds are affecting
the turn and ground references and watching for other air
traffic in the vicinity. This is also used in high reconnaissance,
observation, and photography flight.
Technique
The factors and principles of drift correction that are involved
in S-turns are also applicable to this maneu ver. As in other
ground track maneuvers, a constant radius around a point
requires the pilot to change the angle of bank constantly
and make numerous control changes to compensate for
Downwind half of circle
Upwind half of circle
Wind
Steepest bank
Shallowest bank
Shallower bank
Steeper bank
Figure 9-17. Turns around a point.
Takeoff leg (into the wind)1
Final approach leg5
Crosswind leg2
Base leg 4
Downwind leg3
Wind
Figure 9-18. A standard fixed-wing traffic pattern consists of left
turns, has five designated legs, and is flown at 1,000' AGL.
the wind. The closer the helicopter is to a direct downwind
heading at which the groundspeed is greatest, the steeper the
bank and the greater the rate of turn required to establish the
proper wind correc tion angle. The closer the helicopter is to
a direct upwind heading at which the groundspeed is least,
the shallower the bank and the lower the rate of turn required
to establish the proper wind correction angle. Therefore,
throughout the maneuver, the bank and rate of turn must
be varied gradually and in proportion to the groundspeed
corrections made for the wind.
The point selected for turns should be prominent and easily
distinguishable, yet small enough to present a precise
reference. Isolated trees, crossroads, or other similar small
landmarks are usually suitable. The point should be in an area
away from communities, livestock, or groups of people on
the ground to prevent possible annoyance or hazard to others.
Additionally, the area should be clear and suitable for any
emergency landings should they be required.
Just as S-turns require that the helicopter be turned into the
wind in addition to varying the bank, so do turns around a
point. During the downwind half of the circle, the helicopter’s
nose must be progressively turned toward the inside of the
circle; during the upwind half, the nose must be progressively
turned toward the outside. The downwind half of the turn
around the point may be compared to the downwind side of
the S-turn, while the upwind half of the turn around a point
may be compared to the upwind side of the S-turn.
Upon gaining experience in performing turns around a point
and developing a good understanding of the effects of wind
drift and varying of the bank angle and wind correction angle
as required, entry into the maneuver may be from any point.
When entering this maneuver at any point, the radius of the
turn must be carefully selected, taking into account the wind
velocity and groundspeed so that an excessive bank is not
required later to maintain the proper ground track.
Common Errors
1. Faulty entry technique.
2. Poor planning, orientation, or division of attention.
3. Uncoordinated flight control application.
4. Improper correction for wind drift.
5. Failure to maintain selected altitude or airspeed.
6. Failure to maintain an equal distance around the point.
7. Excessive bank angles.
Traffic Patterns
A traffic pattern promotes safety by establishing a common
track to help pilots determine their landing order and provide
common reference. A traffic pattern is also useful to control
the flow of traffic, par ticularly at airports without operating
control towers. It affords a measure of safety, separation,
protection, and administrative control over arriving,
departing, and circling aircraft. Due to specialized operating
character istics, airplanes and helicopters do not mix well
in the same traffic environment. At multiple-use airports,
regulation states that helicopters should always avoid the
flow of fixed-wing traf fic. To do this, be familiar with the
patterns typically flown by airplanes. In addition, learn how
to fly these patterns in case air traf fic control (ATC) requests
a fixed-wing traffic pattern be flown. Traffic patterns are
initially taught during the day. Traffic patterns at night may
need to be adjusted; for more information, refer to Chapter
12, Night Operations.