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Crosswind Takeoff

The crosswind takeoff requires some timing skills that are not present in other landings. On full power application the yoke is held full over into the wind but not back as in normal conditions. The intention is to hold the up-wind wheel on the ground while remaining firmly enough on the ground to prevent any sideways skipping of the aircraft. As the ailerons become effective only enough is used to prevent side movement.

Although the student has been making takeoffs from the very beginning of training, the crosswind takeoff has a special technique. During the application of power and acceleration the plane must not be allowed to lift off the runway until you are certain that flying speed is acquired. In the C-150 this will be about 55 knots. As with taxiing, the yoke is held full over into the crosswind to prevent the upwind wing from lifting. The nose wheel is kept lightly on the ground.

One of the reasons you should always practice estimating winds at airports that have wind reporting is to develop some skill at direction and velocity estimates. A wind less than 10 knots will take the droop out of a wind sock. Over 15 knots straightens out the sock. The headwind of a 30 degree off runway heading wind should be given full value. Up to 60 degrees off heading should be given only half its velocity value. Beyond 60 degrees the headwind has no value. Rule of thumb says every 10 knots of wind speed reduces takeoff distances by 15%. A 10 knot tail wind will double all distances.

The crosswind takeoff requires a somewhat longer roll before liftoff since there is aerodynamic drag due to the deflection of the control surfaces. This deflection will slow the acceleration. Additionally, the forward yoke pressure required to keep the crosswind side-load from sliding the aircraft sideways prior to liftoff will slow acceleration. When liftoff flying speed is attained at 55 kts the yoke is leveled and given a rather abrupt movement to 'hop' the plane into the air before side loads or skidding can affect the landing gear.

The crosswind takeoff requires some timing skills that are not present in other landings. On full power application the yoke is held full over into the wind but not back as in normal conditions. The intention is to hold the up-wind wheel on the ground while remaining firmly enough on the ground to prevent any sideways skipping of the aircraft. As the ailerons become effective only enough is used to prevent side movement. This aileron change depends on the pilots sense of takeoff speed and the crosswind effect.

Once the speed reaches within five knots of your normal rotation speed a combined series of events should occur. The yoke is leveled and moved relatively abruptly to 'pop' the aircraft off the runway. Once off the runway the plane is held into ground effect and crabbed into the wind with rudder application. The intention is to allow the plane to accelerate quickly while maintaining runway alignment. Unlike the landing, no effort is made to keep the aircraft parallel to the runway centerline.

In the air, rudder is applied to turn the nose into the wind. The hop and rudder application is about simultaneous. The ball is centered. Slight forward yoke is held to set the angle of attack required for normal climb. Once off the ground the aircraft will perform the same without regard to the wind. No effort is made to keep the plane parallel with the runway as when making a crosswind landing. Rather, the plane is crabbed into the wind with the ball centered by rudder. Heading is adjusted to correct drift so as to maintain a ground track in line with the runway center line. When operating from parallel runways it is always a good idea to take a 10 degree cut away from the adjoining runway regardless of the wind. Skill in tracking a line in a crosswind is directly related to ground reference skills.

From an instructional viewpoint the best initial lesson should occur in a crosswind of about 10-12 knots. You want enough to make the cross control position for takeoff necessary but not so much that mistakes will create a hazard. Later lessons should be deliberately planned with ever stronger winds. The student needs to be exposed so as to determine how his ability in this aircraft.

Opinion
There are two distinct techniques used:
1. Keeping the longitudinal axis of the aircraft aligned with the centerline of the runway and maintaining a certain bank-angle to compensate for the crosswind; and
2. Maintaining a crab angle on approach, and applying some rudder just before touchdown to get the aircraft aligned with the runway.

Opinion
Technique #2 actually consists of crabbing into the wind and remaining coordinated for most of the final approach and then converting to technique #1 just prior to touchdown. The trick is in judging just how much slip is required to eliminate any sideways motion at touchdown.

Opinion
Practice makes perfect, but don't get in over your head. Start with a modest, steady crosswind and work up as you become proficient. Don't practice alone, make sure your instructor is there to give advice and keep you out of trouble.

Opinion
Sometimes the simplest explanations are the best.
From a former instructor:
Use the ailerons to compensate for drift away from the centerline, and the rudder to keep yourself aligned parallel to the runway. With this in mind, you'll be using the controls automatically to compensate without realizing it. Like driving a car; do you consciously think of how much pressure to apply to the brakes to stop in a certain manner, or how far to turn the wheel to turn into another street? Probably not; you just do "whatever it takes". Of course the landing/driving analogy breaks down when one considers that you can always see which way the road will go when driving, but you can only react to gusts when landing. But that makes it fun.

Opinion
Put aileron into the wind with opposite rudder during the final approach. If strong winds are present then use a no-flap or partial flap approach. It's that simple. Don't make it more complicated than it is.

Opinion
Wish I could have made it that simple and easy for the students I have taught over the past thirty years. Seems that students have trouble with all the variables of airspeed, wind velocity, bank angle and rudder application. Of all standard flight maneuvers the crosswind landing requires the greatest variety of contradictory control applications.

Opinion
The trick is to separate in your mind the function of the controls. Once you turn on finally, the rudder has one purpose - keeping the nose aligned parallel with the runway, regardless of the position of the runway centerline. The ailerons have just one job, maintaining position over the centerline.

Opinion
Every aircraft is certified as having a demonstrated crosswind capability. This is determined by the winds available at the time of certification. An average pilot should be capable of landing in such conditions. As crosswinds exceed this demonstrated minimum a pilot should minimize flaps and increase approach speed. The maximum aircraft capability is exceeded when full control input is not capable of maintaining directional control even at increased speeds.

Written by Gene Whitt

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