Private Pilot Flight Training and Instruction
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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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