private pilot ground school Articles | Index    

Crosswind Takeoff
2010-03-18

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.

Comment

 
 External Links
 Recent articles
Time For First Solo
This method to safely soloing a student puts the burden on the student It is not the way I do it but it is worth considering ...

Decisions, Decisions, Decisions
P Even the best instruction will not suffice if the student does not show good judgment The student must always be making a series of judgmental decisions...

It's About Judgement
P In flying there are as many ways to gain skill and experience as there are pilots Time alone is a very poor criteria Once pilot...

The Aircraft
Make model serial number and quot;N quot; number can identify an aircraft You should know the year the aircraft was built ...

Midair Accidents In 10 Years 1983-94
236 incidents BR ul li 132 accidents with 56 fatality rate BR li 3 air to air contacts per...

FAA Instructional Format
FAA instruction is based on early 1900 educational theory and practice Most learning is visual but requires repetition and reinforcement for adequate retention ...

Introduction to Illusions
P What ever the illusion it will take a few moments for you to get reoriented If the illusion occurs in trimmed flight the problem is...

Teaching Memory
P The way an instructor presents material has a great influence on student retention of what is being taught Trauma is proven to be the absolute best...

Taxiing
P The nose wheel linkaqe tire pressure spring tension and seat position affect taxiing and often cause turns in one direction to be easier than...

Trim Use
P Correct use of the trim requires that control pressures be applied to hold the desired flight attitude Then the trim is adjusted to relieve present control...

The Unteachable Student
I have found that my methods and I am incompatible with about 5 of my students This was true when I was teaching...

Anticipation
The ability to anticipate changes in control pressures required for a particular maneuver must be developed Failure to anticipate rudder movement required to move...

Are You Ready?
In the real world of life some things are done too soon Getting married having children picking fruit and going into your own business are...

Dealing with Delays
One of the advantages of learning to fly in the fall is the greater probability of weather delays A pilot learns to live with and accept delays of any kind...

The LORAN System
I instructed LORAN at 58th Bomb Wing Training School on Tinian Island of the Marianas during the last year of WWII I also instructed in the use...

You and Illusions
P 1 Illusions can and do occur to everyone BR 2 Proper planning for strange airport conditions is essential BR 3 Weather and...

On Motivation
Students will only learn if they want to Contrary to commonly held parent #39;s opinion children are not inherently resistant to instruction ...

Soft-field Takeoff
P Introduction BR The situation is a takeoff area of unlimited length but having a soft surface the nature of which would prevent acceleration ...

Steep Turns
Va or POH entry speed into 360 turn with bank of 10 5 degrees of 45 U U 100 feet ...

Instructional Safety
When teaching the safest possible flight operations you can show a student how poor decisions doing the same maneuvers could be proportionately more dangerous ...

Post-Landing
P Once on the ground Do not relax Hold the yoke back and properly positioned for taxi For any turns off the runway the yoke should...

Teaching To A Higher Level
P Because of the concentrated information that is being loaded on the student in the beginning I use a tape recorder so that the material is available...

How We Got Pattern A and Pattern B
These patterns have been for many years a part of the Instrument Flying Handbook as among the first lessons in acquiring the aircraft control required for instrument flying ...

Good Judgement
font size 1 color 339966 b Good Judgement b font br P Even the best instruction will not suffice if the...

A Training Program
P I make a practice of having prospective students come to my home office for a couple of hours to discuss flying I request that...

Where To Go; What To Do
P You can find whom to interview by talking to people around the airport Pretty soon certain names will keep coming up Those are the people...

Airport
Markings symbols colors local rules BR Diagram ...

Tie Down
P Given a choice of where to tie down always face into the wind A crosswind tie down means that the aircraft will be trying to ...

Shoulder Harness
1 As of 1975 4 out of every 5 people ever killed in airplanes since the Wright brothers would have been alive if they had been ...

Thinking Through Patterns
P Depending on the student or airport weather conditions I will use paper diagrams and walk through the patterns on the ramp I will illustrate turns about...

Go-around
Power to full BR Hold heading and altitude BR Milk flaps or to 20 degrees according to IAS BR At Vy flaps up and climb...

Crosswind TakeoffCategory
Normal Category is a certification category This category has a maximum G loading of 3 8 G #39;s positive G #39;s 1 52...

Commitment to Flying
ol li You must be able to give priority to the time and energy required for learning to fly If you can #39;t...

1996 For 100,000 Hours of Flying
Singles 1 5 BR Twins 2 12 BR Homebuilts 2 of the flying and 10 of the accidents with aircraft ...

Not Making Progress?
P I doubt that there is a pilot flying who has not at one time or another felt the twinge of doubt that his learning curve is not...

Controlled Airport Radio
P B There are several essentials to good radio work B P P B The first essential is: ...

Test After Failure
67 FAR 61 47 Re testing within 30 days after first failure BR I have given name additional type instruction and find him competent...

Unusual Attitude Recoveries
Nose up Recover with pitch down add power level wings BR Nose down Recover with reduced power level wings pitch to level ...

Trim History
The trim tab or servo trim was invented by Anton Flettner a German aeronautical engineer He started work in 1905 for the Zeppelin Company Died in...

A Need to communicate
P What is the only question an instructor can never answer It is the unasked question Many concerns are unspoken The unspoken fear of every...

The Student As A Student
P How much does it cost Depends on motivation of student BR How long does it take 62 hours is average My students may...

Safe Operation
Use of tow bar BR Why recommended procedures BR Post flight inspection ...

Traffic Patterns
Local rules BR Altitudes U U 100 and speeds U U 10 knots BR The idea of...

Airworthiness Directives (ADs)
P FAR 91 403 a requires that an AD compliance record be kept Some AD are one time and others recurring They notify aircraft owners...

Crash Survival
#1 survival item is to let a responsible person know where you are going your route and ETA Insurance is to make contact after arrival ...

VOR tracking
Tunes and idents station BR Holds altitude within 200 BR Locates position using radials BR Intercepts and tracks a radial BR Recognizes signal...

Teaching Precepts
P Docendo Discimus We learn by teaching When by yourself you are the instructor BR BR ...

ATC Problems in Decending Order
ol li Non adherence to clearance FAR #39;s or published procedures BR li Erroneous penetration of airspace TCA #39;s...

Buchannan Field (at Concord, California)
Within the immediate vicinity of Buchannan Field Concord CA there have been over seven airports over the years One of the very first...

 Related Links
 
©2010 4VFR.COM, All Rights Reserved Powered by 4vfr.com