Aircraft Systems Flashcards
Two flying references may be used on the PFD:
‐ The attitude
‐ The Flight Path Vector (FPV), called the “bird”.
The attitude flight reference should be used for dynamic manoeuvres, for
take-off or go-around.
The bird is computed from
IRS data and is affected by inertial errors. During the approach, the flight crew may detect a small track error, usually up to +/-2 °.
The bird is also computed from static pressure information. Therefore, if the altitude information is not reliable, the flight crew must consider the bird as not reliable.
When using the “bird”, the flight crew should first change attitude, and then
check the result with reference to the “bird”.
The FPV is particularly useful for ___ type of approach.
APPROACH USING FPA GUIDANCE
flight crew can select values for the inbound track and final descent path angle on the FCU.
The TRK-FPA Flight Director (FD) is particularly useful for
guiding the aircraft during non-precision approaches, although, it can also be used at other times.
If the FCU is set on the correct track and flight path angle, and if the FPV and the FPD are aligned, they will
guide the aircraft along a trajectory that is stabilized with respect to the ground, whereas when the pilot is using HDG-V/S, the trajectory is stabilized with respect to the air.
If the aircraft is disturbed from this ideal trajectory, merely following the FPD will result in its following a trajectory that is parallel to the intended trajectory. Thus, when the aircraft is disturbed from the original trajectory, the pilot must
adjust either its track or its flight path angle or both in order to obtain guidance back to the original trajectory.
The flight crew should position the tail of the “bird” on the blue track index on the PFD , in order to
maintain the desired track downwind.
On the final inbound approach, the track index should be set to the final approach course of the runway. A standard 3 ° approach path is indicated, when
the top of the bird’s tail is immediately below the horizon, and the bottom of the “bird” is immediately above the 5 ° nose down marker.
FINAL APPROACH
The “bird” is a very useful flight reference, because it provides
the trajectory parameters, and quickly warns the pilot of downburst.
The position of the “bird” in relation to the fixed aircraft symbol provides an immediate indication of the wind direction. Therefore, when approaching the minimum, the flight crew knows
in which direction to search for the runway.
If the target approach speed symbol moves upward, this indicates that there is headwind gust. If the “bird” drifts to the right, this indicates that there is wind from the left.
For the go-around, the appropriate flight reference is the attitude, because
go-around is a dynamic maneuver. When performing a go-around, regardless of the previously-selected flight reference, upon selection of TOGA, the FD bars are automatically restored in SRS/GA TRACK modes, and the “bird” is automatically removed.
There is inevitably some lag between the pilot’s raising the nose to commence the go-around and the aircraft’s responding by changing its trajectory.
RECOMMENDED PRACTICE FOR AUTOPILOT (AP) ENGAGEMENT
Before engaging the AP, the flight crew should:
‐ Fly the aircraft on the intended path
‐ Check on the FMA that the Flight Director (FD) is engaged with the appropriate guidance modes
for the intended flight path. If not, set the FD on, and the appropriate guidance mode(s) as
required
‐ Center the FD bars with the aircraft symbol on the PFD.
Engaging the AP while large orders are required to achieve the intended flight path may result in
an AP overshoot of the intended vertical or lateral target. This situation can surprise the flight crew, due to the resulting large pitch/roll changes and thrust variations.
If not using FD orders, turn off the FD. It is strongly recommended to turn off the FDs to ensure
the A/THR is in SPEED mode if the A/THR is active.
The A/THR can only be active, when the thrust levers are between
IDLE and the CLB detent.
When the thrust levers are beyond the CLB detent, thrust is controlled manually to the thrust lever Angle, and the A/THR is armed (A/THR appears in blue on the FMA). This means that
the A/THR is ready to be re-activated, when the flight crew sets the thrust levers back to the CLB detent (or below).
___ will, therefore, be the maximum normal thrust setting that will be commanded by the A/THR in CLB, CRZ, DES, or APPR, as required.
MAX CLB
If the flight crew is going to make the landing using manual thrust, the flight crew should disconnect the A/THR by the time the flight crew has reached
1 000 ft on the final approach.
If the flight crew makes a shallow flare, with A/THR engaged, it will increase thrust to maintain the
approach speed until the flight crew pulls the thrust levers back to idle.
In a one-engine inoperative situation, A/THR can only be active, when thrust levers are set between
IDLE and MCT.
In case of engine failure, the thrust levers will be in MCT detent for remainder of the flight.
INSTINCTIVE DISCONNECT (I/D) PUSHBUTTON
If the I/D pb is pressed when the thrust levers are in CL detent, thrust will increase to
MAX CL. This will cause an unwanted thrust increase and may destabilize the approach.
The recommended technique for setting A/THR to off is:
‐ Return the thrust levers to approximately the current thrust setting, by observing the TLA symbol
on the thrust gauge
‐ Press the I/D pb.