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Linda D. Pendleton |
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| About the Author ... |
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Linda D. Pendleton is Manager
of Computer Graphics and Animation for
King Schools.
She is also the author of a book, Flying Jets, and scriptwriter for
several of the training videotapes published by King Schools, including
"Navigation from A to Z," "METAR/TAF Made Easy," and "Handling Emergencies."
Linda is an ATP with Citation 500 and Learjet type ratings, and a CFI with
airplane, instrument and multiengine ratings. In her 10,000+ hours of flight
experience, she's flown US Mail, freight, corporate, charter, commuter, and
served as an FAA-designated examiner for the Citation 500.
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The FAA and I don't agree on something well, more
than one something but I think this one thing is rather important. It's the
way they wrote the Practical Test Standards. Oh, don't get me wrong, I agree
with the idea of the PTS and overall, it's a good thing. It lets everyone know
what is expected and is a great tool for instructors and students alike to
keep training on track. It's the titling of the one of the areas of operation
that gets me a little crazy.
What Is Normal?
Why does the FAA insist on making students and instructors alike believe
that crosswind landings are something fearsome? Area of Operation IV, Tasks A
and B of the Private Pilot PTS are Normal and Crosswind Takeoff and Climbs and
Normal and Crosswind Approach and Landing. If crosswind takeoffs and landings
are not normal, they must be abnormal. If a maneuver is abnormal, perhaps it
is difficult and to be feared or avoided. Crosswind operations are not
abnormal. On the contrary, operations with winds straight down the runway are
abnormal.
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Figure 1. Click on image for larger
version.
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Look at Figure 1. If, for illustration purposes, you limit the wind
direction to 10-degree increments, there are 19 possible wind directions from
the extremes of a direct left crosswind around the compass to a right direct
crosswind. Of those 19 possible directions, only one represents wind directly
down the runway. It seems that not only is having the wind straight down the
runway the abnormal situation, it is statistically unlikely. (I know that this
is a simplification since runways are normally built to be more or less
aligned with the prevailing wind at the airport location, but follow along
with me here.)
Meet The Wind On Its Terms And Deal With It
Wind is a fact. Wind is air in motion, and it is wind air in motion in
relation to the wing that allows us this miracle of flight. Wind is a good
thing. Wind is an everyday thing. Wind is not the enemy, but too many pilots
leave the airplane on its tiedown because "there's a 10-knot
crosswind." Okay, if you don't feel up to it, I guess discretion is the
better part of valor, but perhaps you should grab an instructor and go out and
polish your skills.
How did we become such a bunch of wimps, anyhow? I think two things are at
fault here. The first I've already mentioned the FAA has called crosswind
operations abnormal and pilots have believed that. Second, we have become
lazy. Nosewheel airplanes and especially low-wing airplanes allow pilots
to be less mindful of wind when taxiing around the airport than do tailwheel
airplanes. Since we are not reflexively positioning the controls during all
aircraft movements, it is abnormal when a wind other that one straight down
the runway requires control deflection to keep everything straight on takeoff.
Anyone who knows me will tell you I am a big advocate of standard
procedures. I believe in doing things the same way all the time. That way I
don't have to remember which procedure to call for. I'm getting older and
these old brain cells are not so fast on the recall any longer. I have to keep
it simple to keep it doable. Every takeoff is done the same way line the
airplane up, add power and use whatever controls I need to go straight. It
can't get much simpler than that. That kept me on the assigned pavement in the
Beech 18 and DC-3 days and it works quite nicely in the jets, too.
CFIs, if you teach your students to deal with the wind from the FIRST move
off the tie-downs on that first lesson, wind corrections will come naturally.
You have a unique opportunity when you start a new student. That student has
no idea what is "hard" and what is "easy." If you make
wind correction operations a normal part of the day, then the fear won't
appear. You have a unique opportunity to make things easy for your students.
They will come back to thank you.
What We Need To Do About Wind
Since many CFIs have not taught wind effectively and since taildragger
pilots seem to be a vanishing species, some of us may have to go out and form
some new habits. Be aware of the wind whenever the airplane is not tied down.
Use appropriate controls deflections to taxi. Use aileron into the wind and
rudder to go straight down the runway. Once you are airborne, use that rudder
to keep the ball centered and make a turn into the wind (unless you are on an
instrument departure on an assigned heading) and track straight out the
centerline of the runway. But then you weren't worried about the takeoff, were
you? Pilots never seem to worry about takeoffs. Everyone worries about
crosswind landings.
Crosswind Component
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Figure 2. Click on image for larger
version.
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Your airplane has a demonstrated crosswind component. This number is not
officially an aircraft limitation. It's just the most crosswind encountered on
the day the test pilots happened to be doing that phase of testing. It's a
good number to start with as a guide, however. The demonstrated crosswind
component refers to the component of the wind that is 90 degrees to the
runway. You'll never get that figure from ATIS or the tower or Unicom
operator. Figure 2 is a crosswind component chart. Your aircraft manual
probably has one, too. If you are departing (or landing) on runway 28 and the
wind is reported to be from 250 at 20, what is the crosswind component of that
reported wind? Since the wind is 30 degrees off the nose (280-250) follow the
30-degree line down to where it intersects the 20-knot arc. Drop straight down
from that to the scale on the bottom to determine the crosswind component of
10 knots and straight across to the vertical axis to determine the headwind
component, which in this example is about 17.5 knots. (Notice that the sum of
the components is more than the original 20 knot wind. This is common in
vector math.)
Federal Aviation Regulations require that all airplanes certificated after
1962 have safe ground handling characteristics with a direct crosswind
component of 0.2 Vso. If your airplane stalls at 50 knots in the landing
configuration, it must have a demonstrated crosswind component of at least 10
knots. (0.2 x 50 = 10) Many airplanes do better than the minimum. The Cessna
172R Skyhawk, for example, lists a demonstrated crosswind component of 15
knots.
If you are not comfortable in crosswinds, I don't suggest that you wait for
a day of maximum winds. Start slowly and work up to the maximum. Again, the
demonstrated crosswind component is not an airplane limitation; however, you
are going to have a hard time with insurance company types and lawyers if
something untoward happens and you are operating in conditions that exceed the
demonstrated component. Just be ready to justify your position. Lots of
practice will help with that.
The Crosswind Landing
Landing in crosswinds does take more technique that taking off in them, but
so do all landings require more technique than takeoffs. You are using
aerodynamic controls that depend on air movement over their surfaces for their
effectiveness. As you slow down on the landing, the controls loose
effectiveness. On takeoff, the controls are becoming more effective.
The FAA acknowledges two techniques for maintaining runway alignment on
landing. The first is the crab-into-the-wind method, the second is called by
the FAA "the wing-down" method. It's a side slip to a landing. The
side slip method has one big advantage over the crab it lets you determine
BEFORE the last second whether or not the wind present exceeds the combined
abilities of you and your airplane. In addition, the crab method requires you
to align the longitudinal axis of the airplane with the runway at the last
second before touchdown. Do it a tad too soon or a tad too late and you will
side-load the landing gear. I have never had reflexes that finely tuned, and I
doubt that most pilots do.
The side slip method of landing will work in any wind. Bank the airplane to
put the wing down into the wind. Use rudder to maintain runway heading. Pretty
simple, isn't it? The slip is maintained right through the flare and touchdown
with the touchdown happening on the upwind wheel. The downwind wheel is
allowed to settle to the runway when aileron effectiveness can no longer hold
it up. (For you heavy jet folks that are now picking up pen [mouse?] to write
and tell me that this doesn't work in large, swept-wing airplanes because of
the danger of dragging a wingtip or engine, I know. But until folks get to
that point, this method works pretty well.)
Practice, Practice, Practice
Now, I know this sounds easy and it is once you get the hang of it. Any
good habit you want to form is going to take some practice and reinforcement
and this one is no different. Dealing with the wind MUST become second nature
to you if you want to be a proficient pilot. Grab your favorite CFI and go out
and work on some exercises. One of the best I've found is S-turns across the
centerline. (No, that's NOT really my version of a localizer approach!) You'll
need the CFI to watch out for traffic and to keep track of what you're doing
because you're going to be somewhat absorbed in this exercise.
If you're at a towered airport, ask the tower folks for a low approach over
the runway. If you're at an uncontrolled field, announce your intentions on
CTAF. Fly whatever type approach you feel comfortable with to short final but
make sure you are on the extended centerline. Fly over the runway at just
above touchdown speed and bank the wings into the wind. Keep the heading
steady with rudder. Now, if you start to drift into the wind, take out some
bank until you stop drifting and modify the rudder pressure to maintain that
centerline. If you are drifting downwind, a steeper bank and more rudder
pressure will be needed. Keep practicing this until you can track down the
centerline by reflex. Make sure you select runways that will give you winds
from both directions.
When tracking the centerline like this becomes easy, go looking for more
wind. Work up to your airplane's demonstrated crosswind component. If you find
yourself in a situation where full rudder deflection will not maintain the
centerline with the bank necessary to correct for the wind drift, you know
that the wind conditions exceed the control ability of the airplane. Go find
another runway.
The Easy Part
Once you're proficient at tracking the centerline, the touchdown and
roll-out are a piece of cake. Just let the upwind wheel touchdown first,
followed by the other main, then the nose wheel. Remember that as the airplane
decelerates, you will need to input more aileron deflection to make up for the
decaying effectiveness.
This technique works well. You don't have to ask for a wind check on short
final because you will be comfortable with your ability to handle the ambient
conditions as you sense them. You will know without asking when the wind is
too much for you and your plane. I've used this technique in everything from
Cessna 150s to Beech 18s to bizjets and it's never let me down.
Wind Awareness
Awareness of the effects of wind is not limited to takeoffs and landings.
My instructor once told me (beat into my head is more like it) that a good
pilot always knows three things:
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Where is better weather?
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Which way is
downhill?
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Where is the wind?
These are all, of course, predicated on the fact that you know exactly
where you are at all times, but a good pilot would know that.
It's obvious that you need to know where the wind is to calculate your
time, distance and fuel on cross-country trips. But you also need an awareness
of wind at altitude and at your destination to predict what kind of wind shear
and/or turbulence you may encounter on your approach to your destination.
If you are going to need to divert to an alternate either en route or
because of deteriorating weather at your destination it's always better to
pick an alternate that is downwind from your position. Why? Obviously you will
need less precious fuel to get to a downwind destination.
Make it a habit to be aware of and position the controls for the wind
whenever the airplane is off its tie-down. You'll find the terror draining
right out of those crosswind operations.