.
A300B2/B4 and A300 FFCC:
. A graphical assessment based on the tower wind velocity and wind angle, limited to 15 kt.
The Final Approach Speed
Page 2
No wind correction is applied for tailwinds.
On some aircraft models, the WIND CORR can be entered on the appropriate FMS page.
Flaps configuration:
When several flap configurations are certified for landing, the reference threshold speed (for the selected configuration) is defined as:
V REF full flaps + .V REF.
In calm-wind conditions, in light-and-variable wind conditions and in light turbulence conditions, V REF + 5 kt is a typical target threshold speed.
Abnormal configuration:
System malfunctions (such as the loss of one hydraulic system or the jamming of either slats or flaps) require a speed correction to restore:
.
The stall margin (e.g., loss or jamming of slats and/or flaps); or,
.
The controllability / maneuverability (e.g., loss of part of roll spoilers, V MCL limitation if applicable).
The speed corrections provided in the FCOM and QRH take into account all the consequential effects associated with the primary malfunction
(i.e. no combination of speed corrections is required, unless otherwise stated and explained).
The following rules are used to combine the different types of speed corrections:
.
When two malfunctions affect the stall margin, both speed corrections are added;
.
When two malfunctions affect the controllability / maneuverability , only the higher speed correction is considered;
.
When one malfunction affects the stall margin and the other one affects the controllability / maneuverability, then only the higher speed correction is considered.
These rules are provided herein for enhanced understanding purposes only.
Use of A/THR in SPD mode:
When using the A/THR in SPD mode during the final approach, a 5-kt speed correction on V REF should be added to account for the accuracy of the autothrottle/autothrust system in maintaining the final approach target speed.
This speed correction ensures that a speed equal to or greater than V REF ( V LS ) is maintained at all times down to 50 ft over the runway threshold.
CAT II / CAT III autoland:
For CAT II approaches using the A/THR in SPD mode, CAT III approaches and autoland approaches (regardless of weather conditions), the 5-kt speed correction on V REF is required by certification.
Ice accretion:
When severe icing conditions are encountered, a 5-kt or 10-kt speed correction must be considered to account for the accretion of ice on the unheated surfaces of the aircraft.
Downburst / Windshear:
Downburst / windshear conditions may be anticipated based on;
.
Pilot’s reports from preceding aircraft;
.
Alerts issued by the airport low level windshear alert system (LLWAS); or,
.
Data from a terminal Doppler weather radar (TDWR).
When downburst / windshear conditions are anticipated the landing should be delayed or the aircraft should divert to the destination alternate airport.
If delayed landing or diversion is possible, a speed correction (usually up to 15 kt to 20 kt, based on the anticipated windshear) is recommended.
Landing with less than full flaps is recommended to maximize the climb gradient capability; the final approach speed should be adjusted accordingly.
The Final Approach Speed
Page 3
AIRBUS INDUSTRIE
Flight Operations Support
Microbursts or other types of wind shear usually are characterized by a significant increase of the head wind component preceding a sudden shift to a tail wind component.
When wind shear is anticipated the ground speed should be monitored closely for enhanced wind shear awareness.
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