7.F : Normal and Crosswind Approach and Landing

Knowing that the runway of intended landing is appropriate for the aircraft is the first step in the landing process. Modern AFM/POH documents are standardized such that the landing performance information can be found in Chapter 5, and any limitations are identified in Chapter 2. Violating those performance capabilities and aircraft limitations are likely to cause an incident/accident, so adherence to them is essential.

The landing starts on the downwind leg (see lesson 6-B for more details on the traffic pattern itself). The downwind leg is normally flown parallel to the runway of intended landing, at 1,000 feet AGL, and in the opposite direction of the intended landing. (This norm can be modified and if so will be documented in the Chart Supplement for the airport.)

On downwind the before-landing checklist should be completed, and abeam the landing threshold the descent should be started. For the {aircraft-type} reconfigure the aircraft in the following manner.

When 45° from the runway threshold begin a shallow to medium bank to the left. Usually a descent of about 200 feet will put the aircraft at the 45° point.

This leg is perpendicular to the approach end of the runway of intended landing, and is the leg immediately prior to turning final. On this leg the aircraft should slow to 70 knots, adjusting the pitch and power as necessary to slow from 75 knots to 70 knots.

When flying this leg it is important to maintain the ground track perpendicular to the runway, expecting that there will normally be a crosswind pushing the aircraft away from the runway. Crab as needed to maintain the proper track. The stronger the wind, the closer the base leg should be to the runway. It is normal to descent about 200 feet on this leg.

The turn from the base leg to the final leg should be a medium to shallow bank and should align the aircraft with the runway centerline. The bank should be no more than 30° as above that point the stall speed increases rapidly. This can be extremely unsafe when low and slow. If a steep bank seems required, a go around is probably the correct choice.

When flying this leg the longitudinal axis of the aircraft is aligned with the centerline of the runway, and the final descent to the landing runway is made. The configuration should now be transitioned to an airspeed of 65 knots, and the pitch and power should be adjusted to achieve this performance.

One of the goals during the final approach leg is to establish a stabilized approach. This creates a safe approach, whereas an unstabalized approach risks excessive rates of descent a slow airspeed close to the ground. To achieve this the pilot establishes and maintains a constant glidepath toward a predetermined point on the landing runway with the airplane in a position such that the minimum input of controls will result in a safe landing.

The descent is controlled with power and pitch as necessary to maintain a stabilized approach and glide path. Note that it is possible to enter the region of reverse command which is a point where the aircraft is below LD_max. It is the case that a change in any of the variables requires a coordinated change in the other controllable variables.

For example, if the pilot is trying to "stretch a glide" and raises the nose without adding power (or being able to add power) this can cause the aircraft to settle more rapidly and can actually reduce the gliding distance. Landing short of the runway might be the outcome. The proper angle of descent should be maintained by coordinated use of pitch and power.

The pilot selects an aiming point, which is a point on the ground at which, if the airplane maintains a constant glidepath, and was not flared for landing, it would strike the ground. The pilot should select a point approximately 400 to 500 feet in front of the point of intended touchdown. This accounts for the aircraft’s tendency to float.

Keep that aimpoint steady in the windscreen, since to a pilot moving straight ahead toward an object the aimpoint appears stationary. If the point begins to move up on the windscreen the aircraft is getting too low, and if it begins to move down the aircraft is getting too high. Adjust pitch/power accordingly.

Small corrective actions will result in the airplane making a stabilized steady approach to the aiming point on the runway.

The roundout is a slow, smooth transition from a normal approach attitude to a landing attitude, gradually rounding out the flight path to one that is parallel with, and within a few inches of the runway. Judging the height where the roundout should start is one of the learning challenges for a new pilot. Visual focus should not be fixed on any one side, or to any one spot ahead of the aircraft. The focus should be changing slowly from a point just over the nose, to the desired touchdown zone, and back again. Maintain awareness of the distance from either side of the runway with peripheral vision.

Speed blurs objects at a close range, so the distance at which vision is focused should be proportionate to the speed of the airplane. So as the speed is reduced the distance ahead of the airplane should be brought closer. Focusing too close will result in a blurred reference causing the reactions to be too abrupt or too late. This can result in overcontrolling, rounding out high, or full stall "drop-in" landings. If focus is gradually changed, being brought into focus as speed is reduced, the whole landing process will be smoothed out.

The roundout is started 10 to 20 feet above ground. Power is reduced to idle and back elevator is slowly applied, gradually increasing the pitch attitude and angle of attack. This has the effect of putting the nose in a landing pitch attitude and the increased angle of attack allows the aircraft to settle slowly.

The increasing angle of attack momentarily decreases the rate of descent because lift is temporarily increased. Since the power is at idle airspeed will decrease which subsequently causes lift to once again decrease. This must be controlled by increasing the angle of attack further. This also has the effect of decreasing the airspeed to a touchdown speed, gently settling the aircraft onto the runway.

The rate at which the roundout occurs depends upon the height above ground at which it is started, the rate of descent, and the pitch angle. A high roundout is executed more slowly to allow the airplane to descent to the ground while the proper landing attitude is being established. A low roundout is executed faster to allow the airplane obtain the proper landing attitude before striking the runway surface.

Once the roundout is started the elevator control should not be pushed foward. If necessary relax back pressure or just hold it constant for a short period of time.

The touchdown should be a gentle affair. The aircraft should settle onto the landing surface at the minimum controllable airspeed with the airplane’s longitudinal axis parallel to its direction along the runway. In the ideal landing the airplane’s wheels should be held a few inches off the ground as long as possible with the elevators. In most cases when the wheels are 2-3 inches off the ground the airplane will be settling too fast for a gentle touchdown. The descent must be further retarded by elevator back pressure.

At touchdown the longitudinal axis must be exactly parallel to the direction the airplane is traveling along the runway. Failure to achieve this puts severe side loads on the landing gear. It is important to not land while drifting.

In no-wind conditions, there is less rudder required due to the engine being at idle, and therefore less left-turning tendencies. The airplane will almost fly coordinated by itself.

After touchdown maintain back pressure on the elevator. This maintains a positive angle of attack which enhances aerodynamic breaking, and it holds the nosewheel off of the ground until the airplane decelerates. As momentum decreases gradually relax the back elevator pressure to allow the nosewheel to come down.

The after landing roll is to allow the aircraft to decelerate to the normal taxi speed, or to a complete stop when clear of the taxi area. This is a period of time when pilots can let their guard down, and accidents do happen in this phase of aircraft operation.

Most critically the pilot must maintain directional control of the aircraft. Planes generally fly great, and drive lousy. Be aware that any difference in the direction that the airplane is traveling and the direction it is headed will create a moment about the pivot point of the wheels. This can cause the aircraft to swerve.

Another factor which might impair directional control is weathervaning. If there is a cross-wind the wheels can act as pivot points about which the wind will try to turn the aircraft. Loss of directional control can result in an aggravated, uncontrolled, tight turn on the ground …​. which is known as a ground loop. This is a combination of centrifugal force acting on the center of gravity and ground friction on the main wheels resisting it during the loop. A ground loop can cause an aircraft to lean enough for a wingtip to contact the ground. It can also cause enough side-force on the gear to collapse it. Therefore, as the aircraft decelerates more and more aileron must be applied into a crosswind to keep the upwind wing from rising.

Skidding is not effective, so the maximum effective braking occurs with brake pressure right up to the point just before where the wheels would skid. This is accomplished by gently and evenly applying the brakes (unless they are being used to assist in a turn). Having the brakes engaged at the touchdown time is greatly discouraged as it can cause the brakes to lock immediately, leading to "flat spots" or even blown tires.

This is a landing which must be made with the wind blowing across rather than parallel to the landing direction. The same basic principles are used as in the normal approach and landing, but with a few differences at the end.

There are two methods for accomplishing the crosswind approach and landing. One is the crab method, and the other is the slideslip method. The crab method is somewhat easier, but it requires a high degree of judgment as to when to "kick out" of the crab right before touchdown. For that reason it is not the recommended method.

The sideslip method requires that the pilot lower the upwind wing to cancel the drift induced by the crosswind. To keep the aircraft longitudinally aligned the rudder must also be used, creating a slipping condition.

Using the sideslip method, the pilot should align the airplane’s heading with the centerline of the runway, noting the rate and direction of drift. Promptly add in drift correction by lowering the upwind wing. When the wing is lowered it will tend to turn in that direction (not desired!) so simultaneous opposite rudder pressure is necessary to keep the longitudinal axis of the airplane aligned with the runway. This will cause the aircraft to sideslip into the wind just enough that the drift is canceled (if done right). Changes in the crosswind are corrected for as the aircraft travels down final as needed.

In the case that it is not possible to maintain the centerline, the wind is too strong to safely land on the particular runway because there is insufficient rudder authority to maintain directional alignment. In that case go land on a more favorable runway.

The roundout in the crosswind landing is made much the same was as in a normal landing. However, the crosswind correction is maintained into the roundout to prevent drifting. Do not level the wings. Gradually increase the deflection of the ailerons and rudder to maintain drift correction as the aircraft slows.

The touchdown should be made on the upwind wheel first (due to the wing-low condition the aircraft is using to cancel drift). As the momentum decreases the weight of the airplane will cause the downwind main wheel to gradually settle onto the runway, then the nosewheel.

Once again is is critical to maintain directional control. This is particularly imperative given the possibility of weathervaing. Maintain crosswind control with the ailerons, eventually having full aileron into the wind.

A go around is used if the pilot can not maintain a stabilized approach. This gives the pilot the opportunity to re-fly the approach fixing the earlier problems. It is a mark of good airmanship to go around, and this should be done any time the safety of an approach is in doubt.

The pilot should always use full power, retracting the landing flaps slowly once a positive rate of climb is achieved, and should climb out at V_y. At V_y takeoff flaps can be retracted.

There are a number of obstructions and hazards to consider during the approach and landing. The first is the wind, where a strong headwind might cause the pilot to need to fly the base leg closer, or even fly the approach faster. If there are gusts the approach speed might need to be increased by as much as 1/2 of the gust factor. It is possible that less flaps would be proper in this condition, but the POH/AFM should be consulted for details.

Other obstacles can be trees, towers, or construction equipment. Consult the Chart Supplement and NOTAMs to be warned of any hazards of this nature. Always be alert to traffic as (for instance) an aircraft stalled on the runway might be yet another reason to go around.

Another hazard can be wind shear, or turbulence. Wind shear is an unexpected change in wind direction and/or wind speed. Never conduct traffic pattern operations in close proximity to an active thunderstorm, due to the downbursts possible that can cuse severe wind shear. If the airport has a Low Level Wind Shear Alerting System (LLWAS) it can sometimes give advance warning of wind sheer. Additionally, pilot reports (PIREPs) can be a source of good information regarding wind conditions.

If forced by circumstances to land in wind shear conditions, use extra power and speed to the approach. Stay as high as feasible until necessary to descent, and go around at the first sign of a change in airspeed or unexpected pitch change. Be sure to go to FULL power and get the airplane climbing.

Wake turbulence is generally a problem when operating near large aircraft such as jets. In this situation maintain adequate separation, stay above other aircraft’s glidepath, and when landing (a) land prior to a departing jet’s takeoff point and (b) land beyond an arriving jet’s touchdown point.