.
Perform a partial decrab, using the cross-controls technique to continue tracking the runway centerline; or,
.
Maintain the crab angle, for drift correction, until main-landing-gear touchdown.
Understanding Crosswind Landing Limitations
The following discussion of flight dynamics can provide an increased understanding of the various crosswind landing techniques (i.e., final approach, flare and align phases):
Crosswind landing capability – Design factors
Figures 2 and Figure 3 illustrate the limitations involved in crosswind landing (for a given steady crosswind component).
Getting to Grips withApproach-and-Landing Accidents Reduction
. Bank angle at a given crab angle or crab angle at a given bank angle:
-The graph provides the bank angle / crab angle relationship required to correct the drift and track the runway centerline at the final approach speed ( V APP ) in a steady -side-slip condition.
Positive crab angles reflect normal drift corrections and sideslip conditions (i.e., with the aircraft pointing into wind).
Negative crab angles result from an excessive rudder correction (i.e., aircraft pointing away from wind direction) and require a more-than-desired bank angle to maintain a steady-sideslip.
.
Aircraft geometry limitation :
- This limitation reflects the maximum pitch attitude and/or bank angle that can be achieved without incurring a tail strike or scrapping the engine nacelle, the flaps or the wingtip (as applicable).
.
Ailerons / rudder authority :
- This limitation reflects the aircraft maximum capability to maintain a steady -sideslip under crosswind conditions.
Figure 2 and Figure 3 assume that the approach is stabilized and that the flare is performed at a normal height and with a normal pitch rate.
These figures may not be available and published for all aircraft types and models, but all aircraft are subject to the same basic laws of flight dynamics that these figures reflect.
Geometry limits usually are not a concern in high crosswinds as the roll and rudder authority is reached before any aircraft-to-ground contact occurs.
This assumes achieving a steady sideslip without overcontrol (i.e., without excessive rudder and roll inputs) during the decrab / align phase.
Crosswind Landings
Page 3
AIRBUS INDUSTRIE Getting to Grips with
Flight Operations Support Approach-and-Landing Accidents Reduction
Crab Angle (Degree)
Crab Angle (Degree)
Crab Angle versus Bank Angle
Typical - Maximum Landing Weight - Landing Configuration - 10 kt Crosswind
16 14 12 10 8
Pitch Attitude Limit
6
Roll / Rudder Limit
4
0 Degree Bank-Angle 2
2 Degree
0
4 Degree -2
6 Degree -4
8 Degree -6
10 Degree -8
12 Degree
-10 -12 -14
V APP
Indicated Airspeed (kt)
Figure 2
Crab Angle versus Bank Angle
Typical - Maximum Landing Weight - Landing Configuration - 30 kt Crosswind
V APP
Indicated Airspeed (kt)
Figure 3
Pitch Attitude Limit Roll / Rudder Limit 0 Degree Bank-Angle 2 Degree 4 Degree 6 Degree 8 Degree 10 Degree 12 Degree
Crosswind Landings
Page 4
AIRBUS INDUSTRIE
Flight Operations Support
Figure 2shows that with a 10 kt steady crosswind component:
.
Achieving a steady sideslip landing (i.e., with zero crab angle) requires only a 3-degree into-wing bank angle ( point A plotted on the graph ); or,
.
Achieving a wings level touchdown (i.e., with no decrab) only requires a 4-degree to 5-degree crab angle at touchdown ( point B ).
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