Bank
Steepest
Bank
Shallower
Bank
WIND
Figure 9-17. Turns around a point.
9-18
must be carefully selected, taking into account the
wind velocity and groundspeed so that an excessive
bank is not required later on to maintain the proper
ground track.
COMMON ERRORS DURING GROUND
REFERENCE MANEUVERS
1. Faulty entry technique.
2. Poor planning, orientation, or division of
attention.
3. Uncoordinated flight control application.
4. Improper correction for wind drift.
5. An unsymmetrical ground track during S-Turns
Across a Road.
6. Failure to maintain selected altitude or airspeed.
7. Selection of a ground reference where there is no
suitable emergency landing area within gliding
distance.
TRAFFIC PATTERNS
Atraffic pattern is useful to control the flow of traffic, particularly
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 characteristics,
airplanes and helicopters do not mix well in the
same traffic environment. At multiple-use airports,
you routinely must avoid the flow of fixed-wing traffic.
To do this, you need to be familiar with the
patterns typically flown by airplanes. In addition, you
should learn how to fly these patterns in case air traffic
control (ATC) requests that you fly a fixed-wing
traffic pattern.
A normal traffic pattern is rectangular, has five named
legs, and a designated altitude, usually 600 to 1,000
feet AGL. A pattern in which all turns are to the left is
called a standard pattern. [Figure 9-18] The takeoff leg
(item 1) normally consists of the aircraft’s flight path
after takeoff. This leg is also called the upwind leg. You
should turn to the crosswind leg (item 2), after passing
the departure end of the runway when you are at a safe
altitude. Fly the downwind leg (item 3) parallel to the
runway at the designated traffic pattern altitude and
distance from the runway. Begin the base leg (item 4)
at a point selected according to other traffic and wind
conditions. If the wind is very strong, begin the turn
sooner than normal. If the wind is light, delay the turn
to base. The final approach (item 5) is the path the aircraft
flies immediately prior to touchdown.
You may find variations at different localities and at
airports with operating control towers. For example, a
right-hand pattern may be designated to expedite the
flow of traffic when obstacles or highly populated areas
make the use of a left-hand pattern undesirable.
When approaching an airport with an operating control
tower in a helicopter, it is possible to expedite traffic by
stating your intentions, for example:
1. (Call sign of helicopter) Robinson 8340J.
2. (Position) 10 miles west.
3. (Request) for landing and hover to...
In order to avoid the flow of fixed-wing traffic, the
tower will often clear you direct to an approach point
or to a particular runway intersection nearest your
destination point. At uncontrolled airports, if at all
possible, you should adhere to standard practices
and patterns.
Traffic pattern entry procedures at airports with an
operating control tower are specified by the controller.
At uncontrolled airports, traffic pattern altitudes and
entry procedures may vary according to established
local procedures. The general procedure is for you to
enter the pattern at a 45° angle to the downwind leg
abeam the midpoint of the runway. For information
concerning traffic pattern and landing direction, you
should utilize airport advisory service or UNICOM,
when available.
The standard departure procedure when using the
fixed-wing traffic pattern is usually straight-out, downwind,
or a right-hand departure. When a control tower
is in operation, you can request the type of departure
you desire. In most cases, helicopter departures are
made into the wind unless obstacles or traffic dictate
otherwise. At airports without an operating control
tower, you must comply with the departure procedures
established for that airport.
Downwind Leg
Base Leg
Final Approach
Leg
Takeoff Leg
(Upwind)
Crosswind Leg
Figure 9-18. A standard traffic pattern has turns to left and
five designated legs.
9-19
APPROACHES
An approach is the transition from traffic pattern altitude
to either a hover or to the surface. The approach
should terminate at the hover altitude with the rate of
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