GPS ENR
10 10
20 20
30 30
40 40
20 20
2 -7150
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 360°
ALERTS
Figure 5-27. Horizon line starts moving upward at approximately 27 deg pitch down. Figure 7-70. Horizon line starts moving upward at 27°. Note that the blue sky remains visible at 17° nose-down.
chevrons are positioned at 50° up on the attitude indicator.
The chevrons appear when the aircraft approaches a nose-high
attitude of 30°. The software automatically declutters the PFD
leaving only airspeed, heading, attitude, altimeter, VSI tape,
and the trend vectors. The decluttered information reappears
when the pitch attitude falls below 25°.
For nose-low unusual attitudes, the chevrons are displayed
when the pitch exceeds 15° nose-down. If the pitch continues
to decrease, the unusual attitude recovery protection de-
clutters the screen at 20° nose-down. The decluttered
information reappears when the pitch increases above 15°.
Additionally, there are bank limits that trigger the unusual
attitude protection. If the aircraft’s bank increases beyond
60°, a continuation of the roll index occurs to indicate the
shortest direction to roll the wings back to level. At 65°, the
PFD de-clutters. All information reappears when the bank
decreases below 60°.
In Figure 7-71, the aircraft has rolled past 60°. Observe the
white line that continues from the end of the bank index.
This line appears to indicate the shortest distance back to
wings level.
When experiencing a failure of the AHRS unit, all unusual
attitude protection is lost. The failure of the AHRS results
in the loss of all heading and attitude indications on the PFD.
In addition, all modes of the autopilot, except for roll and
altitude hold, are lost.
The following picture series represents how important this
technology is in increasing situational awareness, and how
critical it is in improving safety.
Figure 7-72 shows the unusual attitude protection with valid
AHRS and air data computer (ADC) inputs. The bright red
chevrons pointing down to the horizon indicate a nose-high
unusual attitude that can be easily recognized and corrected.
NOTE: The red chevrons point back to the level pitch attitude.
The trend indicators show where the airspeed and altitude will
be in 6 seconds. The trend indicator on the heading indicator
shows which direction the aircraft is turning. The slip/skid
indicator clearly shows if the aircraft is coordinated. This
information helps the pilot determine which type of unusual
attitude the aircraft has taken.
Now look at Figure 7-73 . The display shows the same
airspeed as the picture above; however, the AHRS unit has
failed. The altimeter and the VSI tape are the only clear
indications that the aircraft is in a nose-high attitude. The
one key instrument that is no longer present is the slip/skid
indicator. There is not a standby turn coordinator installed
in the aircraft for the pilot to reference.
The magnetic compass indicates a heading is being
maintained; however, it is not as useful as a turn coordinator
or slip/skid indicator.
GPS ENR
10 10
10 10
20 20
-700
-100
-200
-300
50 149
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 360°
ALERTS
Figure 5-28. Aircraft rolled past 60 degrees. Figure 7-71. Aircraft rolled past 60°.
GPS ENR
80 80
70 70
60 60
50 50
40 40
----
-300
00 28
34 133
ALERTS
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 360°
Figure 5-29. Unusual attitude protection with valid AHRS and ADC inputs. Figure 7-72. Unusual attitude protection with valid AHRS.
XPDR 5537 IDNT LCL23:00:34
VOR 1
80 28
TAS 134KT
OAT 7°C
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 360°
HDG
ATTITUDE FAIL
CRS 071° HDG 273°
TRAFFIC
Figure 5-30. AHRS unit failed. Figure 7-73. AHRS unit failed.
Figure 7-74 depicts an AHRS and ADC failure. In this failure
scenario, there are no indications of the aircraft’s attitude. The
manufacturer recommends turning on the autopilot, which is
simply a wing leveler.
With a failure of the primary instrumentation on the PFD, the
only references available are the standby instruments. The
standby instrumentation consists of an analog ASI, attitude
indicator, altimeter, and magnetic compass. There is no
standby turn coordinator installed.
In extreme nose-high or nose-low pitch attitudes, as well
as high bank angles, the analog attitude indicator has the
potential to tumble, rendering it unusable.
Autopilot Usage
The autopilot is equipped with inputs from a turn coordinator
installed behind the MFD screen. This turn coordinator is
installed solely for the use of the autopilot to facilitate the
roll mode, which is simply a wing leveler. This protection
is always available, barring a failure of the turn coordinator
(to aid the pilot if the aircraft attains an unusual attitude).
NOTE: The pilot is not able to gain access to the turn
coordinator. This instrument is installed behind the MFD
panel. [Figure 7-75]
Most EFD equipped aircraft are coming from the factory with
autopilots installed. However, the purchaser of the aircraft
can specify if an autopilot is to be installed. Extreme caution
should be utilized when flying an EFD equipped aircraft
without an autopilot in IMC with an AHRS and ADC failure.
The autopilot should be utilized to reduce workload, which
affords the pilot more time to monitor the flight. Utilization
of the autopilot also decreases the chances of entry into an
unusual attitude.
Flying an EFD-equipped aircraft without the use of an autopilot
has been shown to increase workload and decrease situational
awareness for pilots first learning to flying the new system.
Common Errors Leading to Unusual Attitudes
The following errors have the potential to disrupt a pilot’s
situational awareness and lead to unusual attitudes.
1. Improper trimming techniques. A failure to keep the
aircraft trimmed for level flight at all times can turn
a momentary distraction into an emergency situation
if the pilot stops cross-checking.
2. Poor crew resource management (CRM) skills. Failure
to perform all single-pilot resource management
duties efficiently. A major cause of CRM-related
accidents comes from the failure of the pilot to
maintain an organized flight deck. Items that are
being utilized for the flight portion should be neatly
arranged for easy access. A disorganized flight deck
can lead to a distraction that causes the pilot to cease
cross-checking the instruments long enough to enter
an unusual attitude.
XPDR 5537 IDNT LCL23:00:34
VOR 1
OAT 7°C
NAV1 108.00 113.00
NAV2 108.00 110.60
134.000 118.000 COM1
123.800 118.000 COM2
WPT _ _ _ _ _ _ DIS _ _ ._ NM DTK _ _ _° TRK 360°
HDG
TAS
ATTITUDE FAIL
CRS 071° HDG 273°
TRAFFIC
Figure 5-31. AHRS and ADC failure. Figure 7-74. AHRS ADC failure.
Figure 7-75. This autopilot requires roll information from a turn coordinator.
3. Fixation is displayed when a pilot focuses far too
much attention on one instrument because he or
she perceives something is wrong or a deviation is
occurring. It is important for the instrument pilot to
remember that a cross-check of several instruments
for corroboration is more valuable than checking a
single instrument.
4. Attempting to recover by sensory sensations other
than sight. Recovery by instinct almost always leads
to erroneous corrections due to the illusions that are
prevalent during instrument flight.
5. Failure to practice basic attitude instrument flying.
When a pilot does not fly instrument approach
procedures or even basic attitude instrument flying
maneuvers for long periods of time, skill levels
diminish. Pilots should avoid flying in IMC if they are
not proficient. They should seek a qualified instructor to
receive additional instruction prior to entry into IMC.
Instrument Takeoff
The reason for learning to fly by reference to instruments
alone is to expand a pilot’s abilities to operate an aircraft
in visibility less than VFR. Another valuable maneuver
to learn is the instrument takeoff. This maneuver requires
the pilot to maneuver the aircraft during the takeoff roll by
reference to flight instruments alone with no outside visual
reference. With practice, this maneuver becomes as routine
as a standard rate turn.
The reason behind practicing instrument takeoffs is to reduce
the disorientation that can occur during the transitional phase
of quickly moving the eyes from the outside references inside
to the flight instruments.
One EFD system currently offers what is trademarked as
synthetic vision. Synthetic vision is a three-dimensional
computer-generated representation of the terrain that lies
ahead of the aircraft. The display shows runways as well
as a depiction of the terrain features based on a GPS terrain
database. Similar to a video game, the display generates a
runway the pilot can maneuver down in order to maintain
directional control. As long as the pilot tracks down the
computer-generated runway, the aircraft remains aligned
with the actual runway.
Not all EFD systems have such an advanced visioning system.
With all other systems, the pilot needs to revert to the standard
procedures for instrument takeoffs. Each aircraft may require
a modification to the maneuver; therefore, always obtain
training on any new equipment to be used.
In order to accomplish an instrument takeoff, the aircraft
needs to be maneuvered on the centerline of the runway
facing the direction of departure with the nose or tail wheel
straight. Assistance from the instructor may be necessary
if the pilot has been taxiing while wearing a view limiting
device. Lock the tail wheel, if so equipped, and hold the
brakes firmly to prevent the aircraft from creeping. Cross-
check the heading indicator on the PFD with the magnetic
compass and adjust for any deviations noted on the compass
card. Set the heading to the nearest 5 degree mark closest
to the runway heading. This allows the pilot to quickly
detect any deviations from the desired heading and allows
prompt corrective actions during the takeoff roll. Using the
omnibearing select (OBS) mode on the GPS, rotate the OBS
selector until the needle points to the runway heading. This
adds additional situational awareness during the takeoff roll.
Smoothly apply power to generate sufficient rudder authority
for directional control. Release the brakes and continue to
advance the power to the takeoff setting.
As soon as the brakes are released, any deviation in heading
needs to be corrected immediately. Avoid using brakes to
control direction as this increases the takeoff roll, as well as
provides the potential of overcontrolling the aircraft.
Continuously cross-check the ASI and the heading indicator
as the aircraft accelerates. As the aircraft approaches 15-25
knots below the rotation speed, smoothly apply aft elevator
pressure to increase the pitch attitude to the desired takeoff
attitude (approximately 7° for most small airplanes). With
the pitch attitude held constant, continue to cross-check the
flight instruments and allow the aircraft to fly off of the
runway. Do not pull the aircraft off of the runway. Pulling
the aircraft off of the runway imposes left turning tendencies
due to P-Factor, which will yaw the aircraft to the left and
destabilize the takeoff.
Maintain the desired pitch and bank attitudes by referencing
the attitude indicator and cross-check the VSI tape for an
indication of a positive rate of climb. Take note of the magenta
6-second altimeter trend indicator. The trend should show
positive. Barring turbulence, all trend indications should
be stabilized. The airspeed trend indicator should not be
visible at this point if the airspeed is being held constant. An
activation of the airspeed trend indicator shows that the pitch
attitude is not being held at the desired value and, therefore,
the airspeed is changing. The desired performance is to be
climbing at a constant airspeed and vertical speed rate. Use
the ASI as the primary instrument for the pitch indication.
Once the aircraft has reached a safe altitude (approximately
100 feet for insufficient runway available for landing should
an engine failure occur) retract the landing gear and flaps while
referencing the ASI and attitude indicator to maintain the
desired pitch. As the configuration is changed, an increase in
aft control pressure is needed in order to maintain the desired
pitch attitude. Smoothly increase the aft control pressure to
compensate for the change in configuration. Anticipate the
changes and increase the rate of cross-check. The airspeed tape
and altitude tape increases while the VSI tape is held constant.
Allow the aircraft to accelerate to the desired climb speed.
Once the desired climb speed is reached, reduce the power to
the climb power setting as printed in the POH/AFM. Trim the
aircraft to eliminate any control pressures.
Common Errors in Instrument Takeoffs
Common errors associated with the instrument takeoff
include, but are not limited to, the following:
1. Failure to perform an adequate flight deck check
before the takeoff. Pilots have attempted instrument
takeoff with inoperative airspeed indicators (pitot
tube obstructed), controls locked, and numerous
other oversights due to haste or carelessness. It is
imperative to cross-check the ASI as soon as possible.
No airspeed is indicated until 20 knots of true airspeed
is generated in some systems.
2. Improper alignment on the runway. This may result
from improper brake applications, allowing the
airplane to creep after alignment, or from alignment
with the nosewheel or tailwheel cocked. In any case,
the result is a built-in directional control problem as
the takeoff starts.
3. Improper application of power. Abrupt applications
of power complicate directional control. Power
should be applied in a smooth and continuous
manner to arrive at the takeoff power setting within
approximately 3 seconds.
4. Improper use of brakes. Incorrect seat or rudder pedal
adjustment, with feet in an uncomfortable position,
frequently causes inadvertent application of brakes
and excessive heading changes.
5. Overcontrolling rudder pedals. This fault may be
caused by late recognition of heading changes, tension
on the controls, misinterpretation of the heading
indicator (and correcting in the wrong direction),
failure to appreciate changing effectiveness of rudder
control as the aircraft accelerates, and other factors. If
heading changes are observed and corrected instantly
with small movement of the rudder pedals, swerving
tendencies can be reduced.
6. Failure to maintain attitude after becoming airborne.
If the pilot reacts to seat-of-the-pants sensations when
the airplane lifts off, pitch control is guesswork.
The pilot may either allow excessive pitch or apply
excessive forward-elevator pressure, depending on
the reaction to trim changes.
7. Inadequate cross-check. Fixations are likely during the
trim changes, attitude changes, gear and flap retractions,
and power changes. Once an instrument or a control
input is applied, continue the cross-check and note the
effect control during the next cross-check sequence.
8. Inadequate interpretation of instruments. Failure
to understand instrument indications immediately
indicates that further study of the maneuver is necessary.
Basic Instrument Flight Patterns
After attaining a reasonable degree of proficiency in basic
maneuvers, apply these skills to the various combinations
of individual maneuvers. The practice flight patterns,
beginning on page 7-30, are directly applicable to operational
instrument flying.