Contents:
Landings; ...Certification
Short Field Landing; ...POH Short Field
Landing; ...PTS Short Field Landing;
...Variations on Short Fields; ...Soft-Field
Landing; ...Short, Soft, and Rough landings;
...Controversial Options for the Short Field
Landing; ...POH Emergency Landing;
...Downwind Landing; ...Downwind
in a Crosswind; ...Base in a Crosswind;
...Demonstrated crosswind capability;
...Crosswind Landing; ...Crosswind
Landing Instruction; ...Crosswind Landing
Skills; ...Crosswind proficiency;
...With a Crab and a Kick; ...Power off Landings; ...Power-off
Accuracy Landing (PTS); ...Slip Landings;
...Landing in Turbulence; ...Nose-wheel first; ...Walking
the dog; ...Unusual wind landings;
...Generic Landing; ...Difficult
Wind Landings; ...Salvaging the Landing
Landings
Every landing can be a precision landing within limits. Unlike
a glider, where an airplane touches down is a function of airspeed,
ground effect, and pilot control. A spot landing can be 'faked'
by the use of power or rather the abrupt reduction of power. I
recommend using the runway threshold as your aim point for flare
and then use the yoke and power for the lowest possible touchdown
speed. For practice, use a flare-point up to a thousand feet down
the runway to allow for any misjudgment you might make in your
approach to the 'displaced' threshold.
Pre-decide under what circumstances you will execute a go-around.
You do not need to wait for the runway threshold to make a go-around.
A go-around can be made on downwind if something occurs on the
runway to prevent a landing. Turbulence or extreme winds can affect
your downwind, base or final to preclude a landing. Go-around.
Being high, low, with a fast or slow ground speed can precipitate
a go-around situation. The major factor of any go-around is to
do it without hesitation or doubt. Practice of go-arounds should
not consist of over the runway situations.
Begin your airspeed control and configuration adjustments at the
numbers. Use your downwind airspeed and distance from the runway
to set the initial parameters of your pattern. Adjust trim and
flaps with a constant power setting for wind conditions. On final,
put in full flaps to keep the flare point at or in front of the
threshold. Corrections for being low consist ONLY of full power
while holding approach speed. Corrections for being high consist
of maximum flaps for wind, power reductions in increments as required
to adjust glide slope at constant airspeed. Trim. Slow down to
Vref of 1.2 Vso. Being high or low is visually determined by any
closing or flattening of the space between the flare point and
the selected touchdown. Make a final check of the windsock to
determine if the landing can be made with existing flaps. If not,
go-around.
Throughout the approach all speeds and configurations are at constant
power and trimmed for hands-off control. The POH has a recommended
approach to landing speed range. Use the low end of that range
and recognize that you can fly even slower if you compute Vref
based on weight below gross.
To avoid flare problems you must stop looking at the runway once
over the threshold and look to the far end of the runway while
initially holding the nose level with the runway. As the aircraft
slows deliberately raise the nose to touch the far end of the
runway. Hold it there as you gradually reduce the power. As you
reduce the power raise the nose still more. The ideal, seldom
achieved, is to touch the ground just as the yoke is full back
and the power all the way off. Don't try to see the runway hold
runway alignment with peripheral vision to each side of the nose.
The psychological problem in this landing lies in the instinctive
desire to keep the runway in sight. Accept the fact that a good
landing requires the disappearance of the runway. You can control
your height above the runway by sighting on both sides of the
nose using your peripheral vision. By keeping the horizon from
either rising or falling you can be assured that you are about
to touchdown. A firm touchdown does not hurt the airplane as long
as it is not from over a couple of feet and without any side load.
This landing means that the aircraft is through flying and will
not rise again into the air. Continue to hold the yoke full back
until the nose wheel falls of its own volition.
In a full-stop landing most pilots are advised not to do any post-landing
cockpit changes until clear of the runway. Exceptions to this
might be where your approach speed requires braking that would
damage the tires unless removal of the flaps would increase weight
on the surface.
Certification
Short Field Landing
The primary criteria for landing distance used in certification
has to do with ability to go-around from an aborted landing. A
light aircraft must be able to climb at least 200 feet per minute
(fpm). There are no 'rollout distance' requirements as for commercial
aircraft. The shortest landing distance over a 50-foot obstacle
is based on a 'firm' landing. Preferred threshold crossing altitude
is 50'. This means that touchdown will be 1000' down the runway,
hence the 1000' markers on IFR runways.
POH Short
Field Landing
We have a set of factors so closely interrelated that to adjust
one requires adjustment of all the others. Flaps, speed, and power
only in combination can give the best clearance over the 50' FAA
tree to the flare and ground roll. The approach will clear any
obstacles. With full flaps, the correct speed and some power the
C-150 will approach at about 11 degrees. The approach is as 1.2
times stall speed to touchdown speed of 1.15 times stall speed,
and touchdown at 1.1 stall speed for the weight of the aircraft.
Weight, speed, cleanup, and braking applied determines the ground
roll. Flare will result in little or no floating during roundout
if a precise Vref approach speed is used. Speed will allow stopping
in shortest possible distance without loss of directional control
or damage to the aircraft.
In strong winds a no-flap configuration is recommended. Don't
ever allow a touchdown to occur if there is an uncorrected sidewise
component in your touchdown. Go- around.
PTS Short
Field Landing
The test short field has nine objective items. The first four
apply to pilot knowledge of aircraft performance, the wind and
landing conditions, airspeed and configuration, and the stabilized
approach. The next four are related to the landing performance
during roundout, flare, touchdown, accuracy, braking and directional
control. Item nine is the checklist.
As with any landing, the short field landing is a matter of energy
control. The less energy used in the landing the shorter it will
be. Excess energy is an accumulative negative influence. If, for
any reason, you are not at
the desired speed, configuration, and glide path needed for your
short field approach, GO-AROUND. A well-performed go-around is
an exercise in good judgment and should be a plus on any flight
test. Be prepared for distraction during the critical phase of
a short field landing.
On the flight test talk to the examiner to prove that you understand
the requirements, the function of flaps, and why you make the
final application of flaps when you do. A short field landing
is FIRM. You are not trying for softness. The aircraft is designed
for firm landings without damage. This does not mean that the
landing should not be a smooth transition from roundout, to flare,
to touchdown, cleanup and brakes. Closing the throttle to get
your touchdown, raising the flaps, and applying the brakes occur
in rapid sequence to get on the ground and stopped as quickly
as safety allows.
Variations on
Short Fields
Some pilots and some planes are not well adapted to short
field landings. As a pilot you should memorize or have on your
lapboard the figures for your aircraft's short field performance
in standard conditions. Include touchdown over 50" FAA tree
and rollout. Having the data handy does not mean in the POH behind
the seat. Remember POH figures are for gross. 10% reduction in
weight allows a 5% reduction in approach speed. A 10% reduction
in touchdown speed results is over 20% reduction in rollout distance.
If weights and speeds increase the rollout distance is significantly
longer. A 10-knot tail wind doubles the rollout distance. This
does fall under FAR 91.103.
A problem area associated with short field approaches is some
form of approach path misjudgment. The misjudgment may be of wind
direction, airspeed, flaps, terrain, pilot skill or aircraft capability.
The go-around option exists for all of these situations either
individually or in aggregate. The only time a go-around is a poor
choice is when it is initiated too late. You should go-around
early and make appropriate changes in your approach next time.
A short field landing begins with the arrival at the pattern altitude
and turning down wind far enough away from the airport to fly
a normal pattern. My advice to students is to turn downwind twice
as far away as it seems you should and you will be about right.
The optical effects of a narrow short runway, the tension associated
with landing at a strange and small airport, and previously mentioned
misjudgment factors combine to make the landing unstabilized,
uncomfortable, and unsafe. Go around.
Can you correct major errors in arrival and pattern? Yes, but
not easily. Far more likely you are going to be making steep turns,
low speeds, and worse. The solution begins at the beginning. Plan
your arrival and pattern so that it fits a 5000' runway. Use the
same power changes, flap additions, and airspeeds you have always
used. Only on final, short final, touchdown and rollout will procedures
be any different than normal.
How different? You will fly final at a slower speed than normal.
How much slower will depend on the POH and your gross weight.
At a slower speed your approach angle will be steeper and give
an apparent more rapid descent. This descent if properly trimmed
can be easily controlled. Be judicious with power and trim off
pressures caused by small power changes. Beware the constant decelerating
approach. If low, use full power corrections held for a few seconds.
One very useful option in making a short field arrival is to pre-plan
that you will make a go-around on the first approach regardless.
Soft-Field
Landing
The soft field landing presumes that you have an unlimited
length of runway or at least plenty of room for your rollout,
with field conditions that will bring the aircraft to a semi-abrupt
stop. Rough or soft field conditions require that the aircraft
be held off the surface with power to reduce your ground speed
as slow as possible. If the landing is made so that the nose wheel
touches, it is assumed that the plane will pitch forward and over
on its back. The student's problem is to land in such a manner
that the nose wheel will not touch or stick. The aircraft speed
should be as low as conditions allow. The nosewheel should be
held off the ground with power. Stay off the brakes since this
will cause the aircraft to pitch forward on to the nose wheel.
The touchdown point is not judged for this type of landing. The
idea is to land as slowly as possible and to keep the nosewheel
off the ground as long as you can. Use power to keep the aircraft
rolling nose-high until ground conditions allow the nose wheel
to be lowered.
The landing may be accomplished from a normal approach with full
flaps and by raising the nose in flare sufficient so that when
power is taken off the plane is still airborne. Then, just before
touchdown, power is added sufficient to keep the nose wheel off
the ground. 1300 RPM is about right. More power will start the
plane flying again. Flaps are removed at touchdown and power and
yoke held to keep nose wheel off the ground. Hold the elevator
full back throughout all soft field ground operations. If desired,
bursts of power can be used to keep the nosewheel from lowering
until a firm surface is reached. Avoid any used of brakes. From
the normal approach to landing into the flare the most common
student error in soft field landing is failing to add power just
before to touchdown. The landing is expected to be along the centerline
with no side-loads occurring on the landing gear.
Another technique that avoids the timing of power application
is to complete the entire approach and landing with the power
left at 1300. With practice it can be done with 1200 up to 1500
rpm. With a very smooth and gradual application of yoke, a very
nose high touchdown is possible. Ground effect allows the aircraft
to get the nose well up, especially with power left on. As the
nose rises, rudder must be applied and runway alignment maintained
with aileron. On ground contact the yoke is held back while flaps
are removed. This will increase the effectiveness of the elevators
and the nose wheel will remain clear of the runway until power
is reduced.
The soft-field landing technique is a rather extreme extension
of what it takes to make a good normal landing. In both you would
fly the approach so that, on final; you have a constant airspeed
and full flaps. Low-wing aircraft flaps can be damaged on rough
fields so it is advised to raise them as soon as possible. With
those constants of airspeed and flaps settings, set power becomes
your variable to adjust the glidepath in a soft field landing.
See Practical Test Standards for test specifics.
Short, Soft,
and Rough landings
It is very unlikely that during your training you have been
prepared for short, soft or rough runways. Any field not paved
should be considered both soft and rough. You cannot evaluate
an unpaved airport from the air. Walking or driving the strip
may not suffice either. Paved runways tend to long enough, firm
enough and smooth enough; an unpaved runway is likely to be short,
soft and rough. On the unpaved surface every landing should be
made softly with the nose high and some power. The approach should
be steep, at minimum float airspeed and for a full stall landing.
You should practice the control of the slower airspeed and steeper
approach path of the short field for this landing on a paved runway
before you are going to need it for real. Get the power off and
the flaps up immediately on ground contact. Don't lock the wheels
by too much braking. Keeping the nose wheel off the ground is
more important than braking if the ground is soft. Add 20% to
the performance figures from the POH to allow for your less than
perfect speed control and brake application.
Call locals and use reference material to learn as much as you
can about the field to be used. Wind conditions must be balanced
against such features as clear approach path, up vs. down slope.
The only way to determine field conditions is by walking. Practice
the required approach and landing on a similar paved runway or
a similar unimproved runway with similar characteristics before
trying the real thing. In doing this you will learn what to expect
from your aircraft in performance and yourself in flying capability.
A high proportion of airport accidents occur during the bad weather
months of winter. The root cause lies with airspeed control. Add
1/2 the gust speed to your approach speeds when winds make airspeed
control a problem. You still want to be slow at touchdown. You
will be better off if you are without flaps. You must have the
axis of the aircraft parallel to the centerline. Use the correct
yoke position for the wind direction involved. Keep the aircraft
straight during rollout. Failure to prevent directional changes
of over 10 degrees can result in a rollover or groundloop.
Speed is the critical consideration for any landing. A short field
landing can be made in steady wind conditions at 1.15 Vso. A 10%
lower speed can reduce landing roll by up to 30%. Many pilots
make a practice of holding power until touchdown. Having power
on during a short-field touchdown will be counterproductive to
your short-field intent. You can reduce landing distance by quickly
dumping your flaps since this gets the weight on the tires for
braking. The practice of having a bit of power on short final
may cause a short field landing not to be as short as it should
be.
Controversial options for short field landings:
--Dump flaps while in ground effect to 'plant' wheels firmly.
--Pull mixture to reduce any idle thrust.
POH Emergency
Landing
The ability to conqueror the POH limitations gives us a competent
pilot who can land an aircraft at a slow speed on a long and wide
runway in a short distance. The final examination related to such
summation of limitations is the pilot who can execute a successful
emergency landing at a slow speed and no runway. Does he know
the extent a lighter aircraft total weight reduces the stall speed?
With a lower stall speed and applied flaps the descent angle can
be steeper and more accurate. With lower stall speed, applied
flaps, and power, a slower landing speed and reduced landing roll
is possible. In only one of every six emergency landings is anyone
hurt.
Downwind Landing
The entire downwind approach, even with full flaps, is unexpectedly
flat. Flying the familiar pattern results in a go around. The
aircraft will be moved by the air mass too tight in the pattern.
Trying to adjust the approach and apparent ground speed so that
it is "normal" will not work. Further, if we are not
in the habit of making full stall landings and even if we are,
the landing roundout, flare and roll will require much more runway
length than we would ever expect. It is this unexpected distance
that often makes the inexperienced pilot try to force the airplane
to the ground before it is ready. The resulting flat or hard landing
extends the distance required even more. The controls on the ground
must be held correctly especially if there is a quartering tailwind
during rollout. If you expect to be going into a one-way airport
be sure to get some downwind practice first.
The difficulty with downwind landings is the conflict of previous
performance and perceived performance. We are used to landing
into the wind and the reversal of wind makes things happen differently.
Pilot judgment is impaired by the perplexing unfamiliar ground
speed being greater than airspeed. By failing to fly an exceptionally
extended downwind the full flaps, power off, and minimum approach
speed does not get us down. The C-150 requires at least 50% more
runway with a 10-kt tail wind added to the normal approach speed.
Busy airports frequently will maintain the use of a runway after
the winds reverse direction because of traffic or noise considerations.
Some airports have a calm-wind runway. This calm wind may exist
at ground level but not infrequency the entire approach will be
with a tail wind. The IFR straight in ILS with a tail wind may
be your only option someday. The increased ground speed caused
by the tail wind will make for a very flat approach and a long
landing roll.
While the inadvertent downwind landing may occur during near calm
conditions, it may be required at a one-way airport. This is an
airport for which there is only one landing direction regardless
of wind. Ruth, the northern most airport on the S. F. sectional
is such an airport. This landing as well as cross wind landings,
can be practiced at a non-busy tower airports.
ATC is authorized to use any runway when the 'calm wind is less
than five knots where it is operationally preferred or requested.
ATC will advise of the downwind condition. Pilot requests are
usually honored by ATC.
Downwind in
a Crosswind
The beginning of a good crosswind landing is determined in
how well the pilot maintains the downwind leg a desirable distance
from the runway. If the left pattern crab is toward the runway
then the right pattern crab must be away from the runway. The
key to avoiding any problems in the turn from base to final is
dependent upon not letting the downwind track shorten the base
leg. The decision should be to keep your downwind legs very wide
for all crosswind landings. Skill in maintaining pattern spacing
is acquired during ground reference training. A wide base lets
you adjust your turn to final if high or low.
Base in a Crosswind
Whether a crosswind adds or detracts from your base ground
speed and track, it is important that you plan accordingly. The
base-to-final turn in a crosswind requires specific procedures
to allow you to smoothly align the plane with the runway. If the
cross wind is adding to your ground speed, then the turn will
have the correct wing low and require opposite rudder to align
the nose. If the crosswind is slowing your ground speed, it will
be necessary for you to reverse the turn bank immediately on final
and apply opposite rudder for alignment. Because the turn to final
in each case is so different, it is important to practice both
left and right pattern landings in the same flight and wind conditions.
Anytime the aircraft is in a cross-control configuration on final,
significant forward yoke pressure will be required to maintain
the indicated approach speed.
Even when the base to final is properly turned for runway alignment,
there is considerable difference in how the turn concludes. Unlike
most turns that are completed with the wings level, the crosswind
landing turns from base to final are completed with a wing low
and opposite rudder to align the nose parallel with the runway.
If the base leg has a tailwind adding to your ground speed the
turn to final requires only that the opposite rudder he held for
nose alignment while the wing continues to be held low into the
wind. If the base leg has a headwind the turn to final must be
quickly reversed to the opposite bank from entry while the rudder
is depressed to keep the nose straight with the runway. The more
constant the airspeed the more consistent will be rudder pressures
and aircraft performance. Any time the aircraft is in a cross
control configuration on final, significant forward yoke pressure
will be required to maintain the correct indicated approach speed.
Demonstrated
crosswind capability
When an aircraft is certified by the FAA, it includes a demonstrated
crosswind capability. The capability is based only on the winds
available for that time and day. Some capabilities are based on
relatively light winds. This means that an average pilot with
average competence will be able to land without difficulty. This
is a very poor method of determining the flying limits of an airplane.
It is normal and students should expect to have trouble with all
the variables of airspeed, wind velocity, bank angle and rudder
application when learning crosswind landings. Of all standard
flight maneuvers the crosswind landing requires the greatest variety
of contradictory control applications. Only mastery of the Dutch
roll prepares the student for what is going to happen. The Dutch
roll removes the intellectual process from the uncoordinated used
of controls. If you must think of what to do, you will always
be behind the plane.
The crosswind slip to a landing uses the opposite rudder, as applied
to keep the aircraft centerline parallel to the runway centerline.
The opposing aileron is used to tip the wings so as to slide and
maintain the aircraft centered on the runway approach line. The
greater the crosswind component the more flaps application is
reduced.
Once the crosswind component exceeds that which was used during
the certification demonstration the pilot is advised to adjust
the use of flaps and speed to suit the conditions. Any time the
full application of the controls and increased speed is unable
to maintain directional control the go-around is the only option.
Low touchdown speed gives each knot of crosswind additional effect
so that additional aileron and rudder deflection--and more bank
angle-- is needed to get the slip angle needed to hold runway
alignment. Whatever deflection is needed on final approach is
only 2/3 of what is needed at flare and touchdown.
A student would be ill advised to self-instruct crosswind landings.
Wind gusts can occur that will make the go-around as the only
viable option. Without experience a student is apt to be too late
with too little.
Crosswind
Landing
Everything you need to do in a crosswind is in your imagination.
The use of rudders in a crosswind just involves doing what it
takes. You make the airplane do what it is supposed to do. What
you experience is more what you think has happened and what actually
did happen. Imagine what is supposed to happen and then make it
happen.
As a student working on crosswind landings, or any landings for
that matter, you must be asking yourself an infinite variety of
questions about the process. High, low; close, far; fast, slow;
up, down, in, out; it doesn't matter you must never focus on one
item, the whole process must be put together to make the landing.
As in a poker game, each landing is a new hand that must be bet
and played with the cards you are given
The necessity for a stabilized approach even applies to crosswind
landings. You should hold the crossed controls throughout the
final approach. The crabbing approach, which requires a sudden
application of rudder and aileron during the flare, seems to pose
an unnecessary risk.
The problem of crosswind instruction is not with students; it
is with instructors. All to often I take my students up in a moderate
15-knot 60- degree crosswind for an hour. We are lonely. The FBOs
with their cadre of young instructors have flight restrictions
to protect their equipment. How is a student to learn to cope
with the adversity of a crosswind if the opportunity of exposure
is denied? A crosswind is a learning opportunity. An event to
be challenged, studied, and conquered. If the student should discover
that he is incapable of handling a specific wind, then that, too,
is a valuable lesson. We must learn our limits, how better to
learn them under experienced instruction?
I have had occasion, of late, to fly with several mid-time pilots
who show weaknesses while making crosswind landings. On each occasion,
my first query is as to whether or not they have been taught dutchrolls.
They may have heard of the Dutchroll or may even be able to describe
it. None of these pilots admit having had instruction, proficiency,
or awareness of the Dutchroll relationship to cross wind landings.
Proficiency in the Dutchroll takes the mystery out of how much
rudder and aileron to apply for a crosswind landing. Become sensitive
to signs that will give wind direction and velocity. Check the
windsock on final.
There are two distinct cross wind landing patterns for a given
wind. Left or right patterns in less than 90 degree crosswind
affects the amount of turn required to hold runway heading on
takeoff, the turn and heading to maintain crosswind track, as
well as the amount of turn required for downwind and base legs.
The pilot must learn to take into consideration the velocity of
the crosswind as it influences the ground track of the traffic
pattern. The 90-degree crosswind does not affect track on crosswind
or base except in terms of speed. In a crosswind landing this
runway alignment is doubly important. Each turn from base to final,
left or right will require a completely different rudder/wing
low technique in a crosswind. This can best be practiced where
parallel runways exist or where left/right patterns can be flown
to the same runway. When practicing crosswind landings it is very
important that both left and right patterns be flown to teach
planning of the crosswind, downwind, and base legs as well as
turning to final with the proper wing low/rudder position. The
initial practice of runway alignment can be done in calm to slight
crosswind conditions. Later practice should be done in increasingly
strong crosswinds even to the point of requesting a crosswind
runway not currently in use.
Aircraft that are certified under FAR Part 23.233 requires the
aircraft to be safe for operations in 90-degree winds up to 0.2
Vso. Vso is the slowest speed an aircraft is controllable in landing
configuration, at approach speed, no brakes and no special pilot
skills. For a 60-knot speed with the C-150 this equates at 12
kts. These are minimums. This means that anything beyond a 12-kt.
90-degree crosswind exceeds the design expectations for an average
pilot. If during the certification trials of a given aircraft,
only ten-knot winds were available then that is the limit of the
demonstrated crosswind component. This does not appear to be a
very realistic criteria.
Crosswind Landing
Instruction
To begin with we must assume that the student pilot has flown
the pattern in such a manner as to arrive on the final approach
with appropriate flaps for wind angle and velocity, on glide slope,
and on airspeed.
The basic training exercise for the crosswind landing is the Dutch
roll. The presumption is that mastery of the Dutch roll has prepared
the pilot to keep the aircraft parallel to the runway at all times
on final, while maintaining runway alignment with left-right side
slips as required. My preference is to maintain a constant airspeed
regardless of the slip. This means that the greater the slip the
greater the forward yoke pressure.
In the ideal approach the wind would remain as a constant. This
would mean that the slip angle and required rudder would remain
constant. It doesn't happen. The wind is a constantly changing
approach factor both as to angle and velocity. This means that
the pilot must constantly adjust aileron, rudder, and yoke to
maintain a stabilized approach with constant heading, runway alignment
and airspeed. The essential skill is the previously mentioned
Dutch roll and anticipation of changing conditions before radical
adjustments are required. I very much recommend that extended
straight in approaches as a planned training exercise to give
smoothness to the control applications.
The wind velocity usually decreases during the descent so that
less cross control application is required as the flare approaches.
The actual flare is much as with any other landing but since generally
less than full flaps will be applied greater care must be used
to avoid ballooning. At this point full attention must be paid
to prevent any sideways movement of the aircraft. Landing gear
are exceptionally strong and resilient but they are most subject
to damage when side loads are applied.
If everything goes well the touchdown is made at minimum speed
on the upwind main wheel with the nose wheel and downwind main
still flying. This configuration can be bothersome to passengers
and should be explained as normal before the landing. The wing
low need not be of concern if the aircraft is kept going parallel
to the runway centerline. As the aircraft decelerates the yoke
should be held ever more into the wind and back. The downwind
tire will touch to be followed by the nose wheel. Use rudder as
required in holding a straight course down the runway after the
first touchdown. Correctly done you are now in the proper configuration
for taxiing on the runway.
A crossword on landing will increase stopping distance. The tire
surface contact area provides only so much friction. In a crosswind
this total friction is divided between the effect of the crosswind
creating side-load friction and the braking friction working against
the forward momentum. For this reason expect crosswind rollouts
to be longer.
Other Opinions:
Opinion
The rate of (aileron) reduction depends on the absolute magnitude
of the crossword component and the developing forward speed.
Opinion
I have a different viewpoint. I do not want anyone that I have
taught to arrive at a destination with crosswinds that they have
not been exposed to.
Opinion
My suggestion to you is to get with your instructor on the windiest
day you can and practice x-wind takeoffs and landings to determine
what your maximum capability may be.
Crosswind Landing
Skills
Were I to have all the control I wanted in the teaching of
crosswind landings I would make the first instructional requirement
to be that they should be taught in sailplanes. The necessity
fomented by only getting one shot at a narrow runway would be
sure to focus a student pilot's attention. Ground reference maneuvers
in airplanes do not provide the realism that is required for students
to sense winds in the pattern. The crosswind landing begins on
the downwind. Only by flying the appropriate (wind corrected)
downwind can the base and final be readily adapted to the wind
conditions. The other legs of the approach only compound the problems
of an inappropriate downwind.
In very light crosswinds of 5 kts or less the use of full flaps
should not be a problem. However, I find that most students are
not able to detect, counteract, or otherwise compensate for the
subtle effects of a light crosswind. Dutch roll weakness seems
to be the culprit. I would suggest that under light wind conditions
a student should be set up on an extended final approach to do
the following. Practice side slipping the aircraft left and right
across each side of the centerline. Next sideslip to each side
while stopping momentarily on the centerline to assure that the
nose is being kept parallel and approach speed maintained. This
could be done all the way to the landing as a confidence builder.
Crosswind landings can best be practiced where parallel runways
exist or where left/right patterns can be flown to the same runway.
It is very important that both left and right patterns be flown
to teach the differences in planning for the crosswind, downwind,
base leg, and final. Skill in getting the wing low and opposite
rudder applied is related to how well Dutch rolls can be performed.
Initial practice can be with light crosswinds but true confidence
and capability requires practice in winds of 18 kts or greater.
Towers are usually obliging in the use of crosswind runways.
The velocity of winds usually decrease with altitude. This is
true even for winds below 1000'. If the indicated approach speed
is held along with power and flaps as constants in the approach,
the variable becomes rudder and ailerons. Rudder is used to hold
the nose parallel initially and varied as aileron inputs are used
to maintain runway alignment. Any change in the rudder requires
a change in the ailerons and vice versa. While this is uncoordinated
flight, there is coordination between them predicated upon keeping
the aircraft nose both straight and aligned with the runway. In
this configuration the landing touchdown will be on the upwind
wheel first, then the downwind wheel and then the nosewheel.
Every pilot flying has assumed a degree of responsibility for
his presumption of ability and skill in making crosswind landings.
As a pilot you are expected to have read and understood the significance
of the demonstrated crosswind capability of your aircraft. This
means that at the time of certification a certain velocity crosswind
existed. At this velocity an average pilot would be able to land.
Beyond that velocity you should be a better than average pilot.
Whenever you taxi, takeoff, or land in conditions that exceed
the maximum demonstrated crosswind component you become a test
pilot. FAR 91.13 applies.
Knowing when a wind exceeds your piloting capability is usually
not discovered until too late. You, as a pilot can determine the
wind by entering the wing-low opposite rudder approach early on.
If the approach cannot be stabilized on the approach then a decision
to go-around is a good one. Making the go-around decision before
the press of circumstances adds additional problems, requires
that the pilot think ahead of the airplane. An early go-around
is an indication that the pilot is ahead of the situation and
ready to select a more favorable landing situation. Turbulence
and wind shear are to be expected when winds are active.
The wing-low opposite rudder is an uncomfortable configuration
for most pilots. Being proficient in the Dutch roll makes for
greater proficiency and comfort. It is proficient in the Dutch
roll that makes getting the control input needed automatic. Only
frequent practice will maintain proficiency.
As an instructor I seek out crosswinds. I don't want a student
to be faced with wind conditions that have not been encountered
during dual flight. Each pilot will need to recognize his limits
in a particular aircraft.
The 'demonstrated' limits in the POH are not the limits of a proficient
pilot.
Crosswind proficiency
(Instructor)
Once a student has mastered the basic full flap landing and
go-around it is time to introduce the variations that will be
required for crosswind conditions. The landings will be introduced
when there is no crosswind and may be in only one turn direction.
The first landing is a no-flap power on, the second a no-flap
power off with a slip as required. The next three will be with
10, 20 and 40 degrees of flap. The idea is to develop a student's
perception of how 'high' or 'low' on approach is related to the
aircraft configuration. 60-knot airspeed is used on all approaches.
Each change in configuration requires a slightly differing round
out and flare technique.
A good crosswind flight depends on getting the desired crosswind
at a velocity up to 18 knots. The same series of landings are
discussed on the ground by walking the headings. The variations
of pattern size required by the configurations, even though 60
knots is flown throughout, is a major student learning experience.
The different configurations are flown. Instructor demonstrations
may be required to give the student a 'break'. This lesson should
remove wind limitations from the student logbook. A later short
session should include even stronger winds.
With
a Crab and a Kick (Instructor)
There are two different ways to do crosswind landings, the
slip and the crab. Both can be successful. The crab requires greater
precision, experience, and luck. The crab is a "more comfortable"
approach. The runway comes from the side and does not give the
over-the-nose perspective of most approaches. You will be able
to crab down to the runway in much more wind than you have control
power to slip-kick-land in. An incorrectly timed kick to straighten
the nose or a gust can excessively stress the side load capabilities
of the landing gear box. (The mounting brace in the fuselage.)
The experience required for such timing may be acquired too slowly
or too late for really strong wind conditions. The crab does not
handle gusty conditions well. The go around should be initiated
before the slip-kick else the rapid application of power may cause
loss of directional control.
Instructors planning to teach the crab and kick to slip method
may wish to prepare the student by practicing the slip/opposite
rudder configuration on long final approaches. The slip technique
is relatively difficult to learn to the point of mastery. This
additional practice along with Dutch rolls done on climbout provides
additional exposure.
I do not teach the 'crab' method of crosswind landings because
I feel the method offers too much potential for aircraft damage.
Landing from a side slipping approach does not require such precise
judgment and timing. In a crosswind use a power-on approach and
flaps according to wind angle and velocity. Use additional airspeed
only if needed to increase rudder power. The 1/2 Dutchroll method
keeps both the aircraft path and nose aligned with the runway.
The upwind wing is lowered to intercept and maintain the runway
path and rudder aligns the nose. This method will correct for
any wind velocity or angle up to the control limit of the rudder.
On ground contact the lowered wing and aileron position protects
against gust effects and the ailerons are correctly positioned
for taxi. Full aileron should be applied in the landing roll even
after the downwind wheel makes ground contact.
While there are still advocates (surviving) of the crab and kick
method, the tri-cycle gear aircraft lends itself to the wing low
opposite rudder slip technique. This method allows the pilot to
determine and adjust to the crosswind during descent. Constant
adjustment, similar to those used for a Dutch roll, must be made
to maintain heading and alignment with the runway. The wind is
changing constantly both as to direction and velocity during descent
so the timing of the kick must be just right.
Power-off
Landings (Instructor)
In the mid-60s the FAA changed its 'approach' to the way landings
were to be made as 'standard' for the practical flight test. Prior
to then landings were made power-off. Abeam the numbers, apply
carburetor heat and reduce the power to off, glide and slip to
a landing. With the advent of flaps the steeper, more accurate
glide angle for the approach could be made without slips. The
power off approach made the engine susceptible to carburetor ice
and shock cooling. So the change was made to recommend partial
power landings into the flare. Every power change was to be a
reduction and every yoke movement was to be back and up. Maximum
flaps for the wind conditions is the norm.
Today, just when all the power-off instructors are in short supply
the designated examiners are again requiring power-off landings
as part of their emergency simulation. The reason for this proficiency
test is that today's instructors predominately teach the power-on
landing. The ability of power-on students to execute a power-off
landing, as in an engine failure simulation was detected as an
instructional weakness caused by the emphasis on power-on landings.
Engines last longer without shock cooling. Power-off landings
can be less damaging if the downwind is flown at lower power settings
The power-off approach requires that the pilot pull the power
off when abeam the numbers. From this point the pilot will make
his turns and descent to the runway. This approach is relatively
tight when compared with the power-on. It makes a safe landing
possible even with engine failure. The hazard of the power-on
approach is that the pattern will be such that the runway will
be beyond reach in the event of engine failure. Combining the
engine failure with the power-on approach allows the student to
plan how the failure makes it necessary to re-plan the approach.
Beginning with flap removal and flying directly to the runway.
The throttle setting is an initial constant for the power-on approach
and is not the variable used to correct minor errors of judgment.
Power reductions should occur only on short final and in the flare.
Full power is the best correction for being low on the glide path.
Students learn the power-on method more easily than the power-off
but the landing program should, of necessity, include what to
do in the event of engine failure at any point in the pattern.
Once the power is off, the student is expected to make the runway
as in a real failure.
Power-off
Accuracy Landing (PTS)
During the flight test the examiner can be expected to pull
the power and advise you to make a power off landing within 200
feet of a specific point on the ground. Since you are always expecting
such an event it comes as no surprise. You already know the wind,
don't you? You quickly determine whether to make a 90°,
180°, or 360° approach with adjustments a required.
You also know that two full trim turns down with the power off
will give you a glide speed of 60 knots, hands-off. Just as in
any constant power approach, the power-off approach speed is for
a trimmed 60 knots.
At a constant glide speed, you will be able to sight over the
nose to the runway and determine whether you are high or low.
You have done this many times with 1500 rpm. Power off is no different.
It is your intention not to apply any flaps until you know you
will reach the field, so your no-flap approach will be relatively
flat and high/low somewhat more difficult to assess. Every time
the runway threshold passes under the nose as you fly 60 knots,
you will apply a notch of flaps. Only the straight-in approach
or final limits your ability to adjust base for being low or high.
If your anxiety has kept you too high go into an extreme slip
at 60 knots indicated to get down.
Never dive for the runway. As you know, you can extend your glide
distance by removing flaps. Don't do this below 400 feet unless
you are over a paved two mile runway, except in an emergency.
Get your maximum flaps-for-wind-conditions in before 200 feet
AGL. You will need the altitude to assure complete control in
the round-out, flare, and touchdown. Don't sacrifice a good landing
in your desire to hit a touchdown point. At 60- knots you will
still have 200 feet of float within five feet of the ground. Use
it. Always practice using ground effect in every landing. You
never know when you will need the skill and experience.
Slip Landings
Any time the plane is into the wing low and opposite rudder
configuration forward pressure will be required on the yoke to
maintain the approach speed. The advantage of a constant airspeed
is that rudder pressures and aircraft reactions will be more consistent.
Runway alignment is maintained by how low the wing is held. Nose
alignment is held with rudder. If the nose can't be kept straight
with the runway with full application of rudder then airspeed
must be increased to improve rudder effectiveness. If the nose
cannot be held straight the landing should not be attempted. Go
around and try the landing with little or no flaps.
The pilot's success in acquiring initial runway alignment is predicated
on how well the turn from base to final is planned. This is a
ground reference skill. Holding this alignment with wing low and
rudder applications depends upon mastery of the Dutchroll. When
turning from base to final or when on a long final it is quite
common to find that you are not properly aligned with the runway.
How you make your corrections is important. If you are obviously
far off, you should do something in the order of a 30-degree intercept
to final. If you are only a few hundred feet off line and still
have plenty of altitude, alignment may be achieved by holding
the wing extra low into the wind. If the wind is blowing toward
the runway, level the wings and let the wind blow you into alignment.
If you are 500' from touchdown and have not attained runway alignment
make a go-around.
Being unable to acquire and maintain the wing down and nose straight
alignment with the centerline of the runway is hazardous. This
skill and its associated understanding is a required acquisition
before doing crosswind landings. A smart pilot will make the required
effort to become both skilled and safe in crosswind landings.
Since winds normally decrease in velocity at lower altitudes,
a constant change in rudder and aileron pressures will be required
during descent. I like to advise the student that there is one
wind at 500', another at 50' and still another at 5'. This is
why you must be prepared to make the constant control adjustments
required.
The stabilized approach with a set power, set flap, set trim,
and set airspeed will permit repeated practice of the correct
roundout and flare. If even one of these becomes a variable then
each roundout and flare becomes an experiment with variable success.
Once in the flare, there should be NO abrupt changes. Power and
yoke must be moved slowly initially and then faster logarithmically
to the full off and back positions respectively. Abrupt use of
either power or yoke alone will become precursors of a hard landing.
The go around is the best judgment decision for any approach that
is not stabilized.
The first essential of a good crosswind landing is airspeed at
Vso. This slow speed minimizes all the problems that result from
high speeds on touchdown. Speeds higher than Vso use more runway,
require excessive braking, extend the influence of ground effect
or float, and increase the bounce and porpoise likelihood. Touchdown
as slowly as you can.
Secondly, the touchdown point is in the first third of the runway.
A stabilized approach at the correct airspeed will give you a
visual aim at the runway. If low, you add full power and hold
the approach speed until you regain the glide slope. If high,
you add appropriate flaps, reduce power, reduce airspeed in that
order and prepare to go-around.
Third, keep the nose parallel to the runway. There is frequently
a problem with the student who is concerned with landing on one
wheel and the rudder pushed in. Because of this concern he releases
the rudder prior to touchdown along with other control pressures.
This results in many of the bad effects of the poorly executed
crab landing. Both main wheels touchdown at the same time, the
nose wheel hits with them. Side loads are applied to the landing
gear and very possibly the aircraft weathervanes into the wind.
These are all the negatives in a crosswind landing that result
from directional imprecision.
Landing in
Turbulence
Don't use flaps. This will keep the nose higher and closer
to the proper landing attitude. Touchdown speed may tend higher
as the wind angle approaches 90-degrees. This should be recognized
and avoided since a 90- degree crosswind makes airspeed the same
as ground speed. Any increase in ground contact speed will multiply
any side load effects. Failure to correct for a crosswind will
cause damaging sideloads and directional control problems.
The potential sideloads of a crosswind increases as the square
of the velocity. Even at low wind speeds the effects can be dramatic.
2 kt. wind 2x2 = factor of 4 sideload; 3 kt. wind 3x3 = factor
of 9 sideload; 4 kt wind 4x4 = factor of 16 sideload. Double the
number gives quadruple the sideload.
Keep power on during the approach and add one-half of the gust-factor
to your approach speed. Do not seek a full stall landing. Fly
the aircraft on to the runway, pull the power off and don't get
any more weight on the nosewheel than may be required for steering.
Remove any flaps. Permitting weight to be applied to the nosewheel
will transfer weight from the main landing gear. Too much of such
a transfer will cause the main wheels to lift off and lose traction.
You are now steering a wheelbarrow with the rudder. Your safest
option is to go-around. Salvaging a wheelbarrowing landing is
not for the faint of heart.
Nose-wheel first
A properly rigged aircraft can be trimmed for hands-off flight.
The properly rigged airplane has an longitudinal oscillatory pitch
mode which once properly trimming will allow the plane to return
to that first flight condition even if the nose is moved. The
nose will oscillate at first as it returns to the original attitude.
The plane is also subject to PIO (pilot induced oscillations)
where the pilot, due to the delay in instinctive reaction, may
push and pull at just the wrong time so as to amplify the movements.
The PIO can only be broken by locking the elbow against the side
of the cockpit.
This PIO is most likely to occur in a tricycle aircraft where
the nose-wheel is allowed to come into contact with the runway
with such force that the nose-strut is compressed. Instinct now
takes control over the pilot's
training. At moment of contact the pilot pulls back on the yoke
to get the nose up. The nose strut reacts to its compression at
the same time and together the nose goes beyond the critical angle
of attack. Again at the same time the wing stalls and falls as
the pilot pushes forward. The instinctive timing is only a second
out of synchronization but that is enough to cause the nose-wheel
and strut to again make a compression strike on the runway just
as the pilot is trying to pull back to keep the nose from falling.
If a go-around is not initiated on this second strike the nose-strut
will strike even harder the third time to the point of collapse
and propeller strike.
The go-around is absolutely the best option at the first sign
of a nose-low touchdown. The rule is that NEVER move the yoke
forward to correct being high in the flare. It is acceptable to
stop any backward/up pressure but
any forward pressure is most likely to result in the scenario
above. Ideally, all yoke movements should be back and up.
Part of the FAA certification process is to check the designed
stability and control authority of the plane. Within specified
center of gravity limits an average pilot can make the plane perform
adequately. Outside the specified C. G. limits or in a nose-wheel-first
landing the one second reaction delay of the pilot will make things
worse...every time.
Walking the dog
This is a ground level maneuver along a very long runway in
which the alternate wheels are allowed to touch the runway while
the nose is held straight. Nose wheel is held clear. Exercise
is best done in a no wind condition. Power is on the whole time
with slight increases used going from one wheel to the other.
Unusual wind
landings
Last week, as I walked up to the plane, I momentarily stopped
and felt the wind. It was very light but could be perceived as
a tail wind for the noise abatement runway currently in use. I
had my student, sitting in the plane, get out and asked him to
feel the wind. What followed was an analysis of what happens when
a wind is classified as "calm". Even more importantly,
we covered all the effects for the even greater probability that
the wind would be "light and variable". We did some
watching of aircraft making their landings. Landings were consistently
long on the 5000' runway. Also, the landings were usually off
to the side of the centerline.
On average, landings are made into runways with the twelve-knot
relatively constant velocity and direction winds. Most of our
practice and landings are into such winds plus or minus a knot
or two. This experience has taught us to make the adjustments
to the pattern and aircraft configuration required producing a
satisfactory landing. "Calm winds" do not provide the
clues the inexperienced pilot has come to expect. The light tail
wind will increase the ground speed and shallow the approach angle.
The usual changes in flaps, power, and airspeed fail to produce
the desired results. This is caused by the fact that, while the
tail wind may exist from 600 feet down to 100 feet the winds higher
and lower will be from different directions and velocities. Even
the tail wind will vary in velocity on final. The momentary truly
calm wind compounds the difficulties.
The solution I offered my student was to extend the down wind
leg of the pattern by twenty to thirty seconds any time the ATIS,
wind sock, or AWOS indicates a calm wind condition. This adjustment
allowed for the more shallow approach angle caused by the increased
ground speed. The student was on a good approach but a new "calm
wind" problem arose. In the flare the aircraft would begin
a barely perceptible drift off the center line.
It seems that the intensity of the landing itself often so focuses
the attention of the student that he/she is completely unaware
of drift unless it is either pronounced or occurring just before
touchdown. The likelihood or probability of this condition occurring
must be pre-registered into the mind of the pilot any time the
"calm" condition exists. With the runway out of sight
in a proper flare the pilot must get his clues from the peripheral
vision and the horizon. This takes both practice and experience
especially in calm conditions. A failure to correct even the slightest
side load on the landing gear is potentially very harmful to the
aircraft since this is the weakest area of landing gear geometry.
The instructor who does not foresee this area of landing difficulty
is not properly anticipating an area of difficulty.
A few day prior to this flight another student and I had winds
at 23 knots with higher gusts 40 degrees off the runway heading.
Once again I proceeded to talk and walk through the headings for
both left and right traffic that would produce an appropriate
pattern. Just to get into the plane and start doing landings in
these conditions would have been most inappropriate. We were transitioning
the student from a C-150 to a C-172. This was his third C-172
flight but his first since getting his license.
In the pattern walk through, I gave the student the needed opportunity
to see that some operational adjustments would be required. The
initial takeoff would cause us to gain altitude over less distance
so that our crosswind would need to be flown angled well into
the wind and extended somewhat to create a wider downwind. The
turn downwind would need to be angled away from the runway since
it was necessary to fly a somewhat wider downwind leg both because
of being in right traffic and because the wind direction would
produce a an effectively shorter base leg due to a higher ground
speed. The power reduction would begin before the numbers and
even more angle into the wind would be taken to counter the increased
wind effect at a slower airspeed. The wider downwind would give
us a base leg sufficiently long to allow adjustments in the length
and height of our final approach. The instructional emphasis here
is that the pilot's control over the final approach must begin
on the downwind leg if not sooner.
Under these or similar conditions the landing must be considered
an option not a necessity. The go-around is the first choice option
if the stabilized final approach cannot be established.
Flying the same runway in left hand traffic in the same wind conditions
requires the pilot to make a shorter crosswind to help counter
the wind's efforts to drift the aircraft away from the runway.
The downwind leg
must be angled toward the runway. The base leg again must be sufficient
to allow adjustments to the height and length of the final approach
course.
The instructional process for landings is not complete unless
it exposes the student to the wind conditions described above.
The opportunity to fly both left and right patterns in the same
crosswind conditions is essential. Variety of pattern and conditions
can be created by going to controlled airports with multiple runways.
ATC will honor requests for crosswind runways and different patterns
when traffic conditions allow. Changing the time of day is a good
way to obtain varied wind velocity.
Training and recurrent training will not provide competence unless
the pilot puts the training to work as a foundation for building
experience. Training should not be confused with competence. Training
is but a path for the pilot to follow to achieve competence. Do
not believe that training will do the job for you that more flying
will. Training does not lead to competence. Competence comes mostly
from experience gained in flying.
Generic Landing
The landing climaxes at the point of touchdown but will not end
there. Furthermore, the beginning of a particular landing occurred
at some past landing where a lesson was learned when the pilot
was high, low, fast, slow or out of control. The mistake of the
past is avoided, corrected and blended into a successful landing.
Not perfect, just satisfactory.
The satisfactory landing begins with aircraft control. Aircraft control is the pilot's ability to perform the four basics of climb, descent, level, and turns within a predetermined tolerance level. Aircraft control also includes the ability to use the four basics to position the aircraft in the landing pattern within another predetermined tolerance level of distance and altitude. The last element of aircraft control has to do with configuration. Wind and terrain are used by the pilot to select the optimum configuration for the situation. The so-called stabilized approach to landing begins far before turning final. The amount of tolerance allowed by an instructor is a variable based on how close you are to doing solo landings.
In the landing practice pattern the takeoff and climb to downwind can be just a precise as any other part of the pattern. The lift off occurs at Vso or slightly higher in crosswind conditions. Climb is delayed until Vy unless Vx is a requirement. Runway alignment is maintained with crab as appropriate with at least one visual check around 300 feet. Takeoff ranks #2 behind landings as a source of accidents. You can't achieve a successful landing without first making a successful takeoff.
The turn to crosswind is initiated after visually clearing the turn area and selection of a visual or heading reference. In the turn the eyes and head are not turned but are used to maintain attitude, bank and airspeed until the visual point comes into view. Very slight forward pressure is used both during entry and recovery from turns if a constant airspeed is to be maintained. At the thirty-degree point of bank, back pressure is used to maintain airspeed. All climbing turns are with coordinated controls at altitudes according to local practices at Vy. Entry and recovery from the turn bank is coordinated with anticipated rudder and aileron as required by the direction. Begin turn recoveries 15 degrees early. Left and right climbing turns are significantly different and should be practiced equally.
Just where the turn to downwind occurs is usually determined by wind and terrain conditions but occasionally traffic may require turns sooner or later. The width of the downwind must be adjusted wider for any wind that blows the aircraft toward the runway and closer to prevent a wind from blowing the plane too wide. This downwind adjustment is a critical flight positioning of the pattern which can only be made with repeated exposure to varying conditions. A short base is a prelude to tragedy.
Leveling the aircraft at pattern altitude and anticipating the amount of trim required must be done according to the downwind speed desired. There is no one best way to select this speed. My personal preference is to use level cruise speed for several reasons. Trainers are the slowest aircraft in the air. Using a slow trainer speed downwind places unfair hardship on non-training aircraft in the pattern. The cruise speed is a familiar trim, power, and sound condition. The reduction of power at the numbers while maintaining heading and altitude gives a relatively constant key position for the base turn. Most urban airports require (request) that pattern altitudes be maintained until turning base. This technique allows each aircraft to select its pattern key position according to its performance.
There is a helpful logic behind ATC always requesting that
you report a two-mile final or two-mile base. A 45-degree entry
to downwind to a mile-long runway would allow a mid-field downwind
turn 1/2 mile from the
numbers. A 45-degree entry to downwind to a shorter runway should
be made at the departure end to prevent the optical illusions
that lead to close-in downwind patterns. With a half-mile to do
the pre-landing before reaching abeam the numbers, another half-mile
to slow down and reach the key position, still another half-mile
base, and a half-mile final we have adapted the ATC two-mile base
and straight-in to the basic downwind entry.
On downwind you should make a preliminary decision as to the flap configuration you will use. The POH standard is to land with full flaps if wind conditions allow. Just how you set the power, apply flaps, and trim for an airspeed is multi-task variable. Whatever you choose to do should have a consistency. Only in simulated emergency or short-short approaches should power be taken all the way off. Shock cooling the engine is a relatively dangerous practice. Whatever the power and flap setting the trim should be adjusted for the hands-off airspeed desired. Do not accept trimmed airspeeds off the desired speed. Most trainers use the same approach speed from the key position, to base, to final, to the round-out. Beyond the trainer, aircraft will use two or three different speeds from downwind, base, and final.
One variable that often occurs in downwind is an ATC call or situation that puts you as #3 to land or a need that you extend your downwind. In both cases you initiate the slow-flight procedure immediately even before using the radio. You want to avoid getting too far from the airport if possible. You hand-fly the slowflight by using the same trim as you would have but add about 500 rpm to hold altitude and 10 degrees of flap to improve over the nose visibility. Resumption of the approach requires only reduction of power.
My preference is to reduce power to whatever setting will give me 1500 rpm when I reach the key position. At the key position I will have maintained altitude and trimmed for my base approach speed, I put in one notch of flaps hold that airspeed with forward yoke and retrim while turning base. I have learned to put in flaps, apply forward pressure, and trim without looking any place except over the nose of the aircraft. I have begun my descent and am trimmed hands-off. Once my aircraft is under control I look to see the airport. A major fault of those who lose control is mixing up their priorities.
I make most of my approach adjustments on base. I may add a second notch of flaps, fly a wider base, or one closer in. Occasionally, ATC may ask you to make an adjustment by asking that you, "square your base" or "fly directly to the runway". Regardless of what you do, do it at a constant airspeed. Only by having a constant airspeed can you develop the skills needed in determining a stabilized approach angle.
On final and on final approach airspeed I use the nose as a sight to make my high/low decisions. By aiming short of the runway a hundred feet you can become experienced in the use of ground effect. Being high offers the most corrective options; I can add flaps to maximum for wind conditions; I can reduce power in increments of 100 rpm or more; or, I can reduce my approach speed to cover less ground for altitude lost. Runway permitting I assume normal approach speed just prior to round-out. The universal solution for being low consists of adding full power while holding approach speed for an estimated time needed to intercept normal glide path.
Other opinions to the contrary, small additions of power can cause a pilot to enter into a condition known as 'the constantly decelerating approach'. As the power is added, the speed drops until there is not enough power to maintain altitude. You are behind the power curve and with the ground close by you have run out of options. The worst thing that could happen to a low-time pilot is to 'get away' with additions of power that lead to the decelerating approach. Next time you may not get away with it.
Difficult
Wind Landings
I have read that world-wide the average wind has a velocity of
about twelve knots. At each end of this reference are wind extremes
that can and do cause pilots pattern and landing difficulties.
One extreme the strong winds are expected while the other extreme,
the so called calm wind, has unexpected capabilities. A student
should be exposed early to runways of varied widths and lengths
in both left and right patterns Each of these extremes offer specific
problems that can be solved only by a varied exposure. Once exposed
a pilot will better avoid problems by using the skills of anticipation
he has acquired.
Last week, as I walked up to the plane, I momentarily stopped and felt the wind. It was very light but could be perceived as a tail-wind for the noise abatement runway currently in use. I had my student, sitting in the plane, get out and asked him to feel the wind. What followed was an analysis of what happens when a wind is classified as "calm". Even more importantly, we covered all the effects for the even greater probability that the wind would be "light and variable". We did some watching of aircraft making their landings. Landings were consistently long on the 5000' runway. Also, the landings were usually off to the side of the center line.
On average, landings are made into runways with the twelve knot relatively constant velocity and direction winds. Most of our practice and landings are into such winds plus or minus a knot or two. This experience has taught us to make the adjustments to the pattern and aircraft configuration required to produce a satisfactory landing. "Calm winds" do not provide the clues the inexperienced pilot has come to expect.
The light tail wind will increase the ground speed and shallow the approach angle. The usual changes in flaps, power, and airspeed fail to produce the desired results. This is caused by the fact that, while the tail wind may exist from 600 feet down to 100 feet the winds higher and lower will be from different directions and velocities. Even the tail wind will vary in velocity on final. The momentary truly calm wind compounds the difficulties.
The solution I offered my student was to extend the down wind leg of the pattern by twenty to thirty seconds any time the ATIS, wind sock, or AWOS indicates a calm wind condition. This adjustment allowed for the more shallow approach angle caused by the increased ground speed. The student was on a good approach but a new "calm wind" problem arose. In the flare the aircraft would begin a barely perceptible drift off the center line.
It seems that the intensity of the landing itself often so focuses the attention of the student that he/she is completely unaware of drift unless it is either pronounced or occurring just before touchdown. The likelihood or probability of this condition occurring must be pre-registered into the mind of the pilot any time the "calm" condition exists. With the runway out of sight in a proper flare the pilot must get his clues from the peripheral vision and the horizon. This takes both practice and experience especially in calm conditions. A failure to correct even the slightest side load on the landing gear is potentially very harmful to the aircraft since this is the weakest area of landing gear geometry. The instructor who does not foresee this area of landing difficulty is not properly anticipating an area of difficulty.
A few day prior to this flight another student and I had winds at 23 knots with higher gusts 40 degrees off the runway heading. Once again I proceeded to talk and walk through the headings for both left and right traffic that would produce an appropriate pattern. Just to get into the plane and start doing landings in these conditions would have been most inappropriate. We were transitioning the student from a C-150 to a C-172. This was his third C-172 flight but his first since getting his license.
In the pattern walk through, I gave the student the needed opportunity to see that some operational adjustments would be required. The initial takeoff would cause us to gain altitude over less distance so that our crosswind would need to be flown angled well into the wind and extended somewhat to create a wider downwind. The turn downwind would need to be angled away from the runway since it was necessary to fly a somewhat wider downwind leg both because of being in right traffic and because the wind direction would produce a an effectively shorter base leg due to a higher ground speed. The power reduction would begin before the numbers and even more angle into the wind would be taken to counter the increased wind effect at a slower airspeed. The wider downwind would give us a base leg sufficiently long to allow adjustments in the length and height of our final approach. The instructional emphasis here is that the pilot's control over the final approach must begin on the downwind leg if not sooner.
Under these or similar conditions the landing must be considered an option not a necessity. The go-around is the first choice option if the stabilized final approach cannot be established. Flying the same runway in left hand traffic in the same wind conditions requires the pilot to make a shorter crosswind to help counter the wind's efforts to drift the aircraft away from the runway. The downwind leg must be angled toward the runway. The base leg again must be sufficient to allow adjustments to the height and length of the final approach course.
The instructional process for landings is not complete unless
it exposes the student to the wind conditions described above.
The opportunity to fly both left and right patterns in the same
crosswind conditions is essential. Variety of pattern and conditions
can be created by going to controlled airports with multiple runways.
ATC will honor requests for crosswind runways and different patterns
when traffic conditions allow. Changing the time of day is a good
way to obtain varied wind velocity.
Salvaging
the Landing:
How do you know how and when to salvage a landing? Can some poor
approaches and flares be safely corrected? The answer is yes.
You must have very deep pockets to afford salvaging landings.
As previously indicated. Your best option will be the go-around.
Judicious additions of power may be applied and be successful.
A combination of luck and experience may work. My recommendation
is that all salvage efforts be delayed until you are using your
own airplane.
An old PTS guide once said that the ideal landing occurred when at the moment of touchdown, the yoke was all the way back, the power was reduced to off, and the stall warner would bleep. As the pilot you are striving for this ideal. It does not occur often. The flare and landing is an act of faith. You must believe that the runway will be there. You will not know just when the landing will occur.