Rotorcraft Flying Handbook, FAA-H-8083-21

AUTOROTATIONS
Both straight-ahead and turning autorotations should
be practiced by reference to instruments. This training
will ensure that you can take prompt corrective action
to maintain positive aircraft control in the event of an
engine failure.
To enter autorotation, reduce collective pitch smoothly
to maintain a safe rotor r.p.m. and apply pedal trim to
keep the ball of the turn-and-slip indicator centered.
The pitch attitude of the helicopter should be approximately
level as shown by the attitude indicator. The
airspeed indicator is the primary pitch instrument and
should be adjusted to the recommended autorotation
speed. The heading indicator is primary for bank in a
straight-ahead autorotation. In a turning autorotation, a
standard rate turn should be maintained by reference to
the needle of the turn-and-slip indicator.
COMMON ERRORS DURING AUTOROTATIONS
1. Uncoordinated entry due to improper pedal trim.
2. Poor airspeed control due to improper pitch attitude.
3. Poor heading control in straight-ahead autorotations.
4. Failure to maintain proper rotor r.p.m.
5. Failure to maintain a standard rate turn during turning
autorotations.
SERVO FAILURE
Most helicopters certified for single-pilot IFR flight are
required to have autopilots, which greatly reduces pilot
workload. If an autopilot servo fails, however, you
have to resume manual control of the helicopter. How
much your workload increases, depends on which
servo fails. If a cyclic servo fails, you may want to land
immediately as the workload increases tremendously.
If an antitorque or collective servo fails, you might be
able to continue to the next suitable landing site.
INSTRUMENT TAKEOFF
This maneuver should only be performed as part of
your training for an instrument rating. The procedures
and techniques described here should be modified, as
necessary, to conform with those set forth in the operating
instructions for the particular helicopter being
flown.
Adjust the miniature aircraft in the attitude indicator,
as appropriate, for the aircraft being flown. After the
helicopter is aligned with the runway or takeoff pad, to
prevent forward movement of a helicopter equipped
with a wheel-type landing gear, set the parking brake
or apply the toe brakes. If the parking brake is used, it
must be unlocked after the takeoff has been completed.
Apply sufficient friction to the collective pitch control to
minimize overcontrolling and to prevent creeping.
Excessive friction should be avoided since this limits
collective pitch movement.
After checking all instruments for proper indications,
start the takeoff by applying collective pitch and a predetermined
power setting. Add power smoothly and
steadily to gain airspeed and altitude simultaneously and
to prevent settling to the ground. As power is applied and
the helicopter becomes airborne, use the antitorque pedals
initially to maintain the desired heading. At the same
time, apply forward cyclic to begin accelerating to
climbing airspeed. During the initial acceleration, the
pitch attitude of the helicopter, as read on the attitude
indicator, should be one to two bar widths low. The primary
and supporting instruments after becoming airborne
are illustrated in figure 12-22. As the airspeed increases
50 60 70 80
40 TORQUE 90
30
100
20 PERCENT
110
10
0
120
Supporting Pitch
Primary Pitch
Supporting Bank
Supporting Pitch
Primary
Power
Supporting Bank
Primary Bank
Supporting Pitch
Figure 12-22. Flight instrument indications during an instrument takeoff.
12-19