Page 3.41 (2,160)
Planning
Arrivals
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Contents
Airport Operations; …Arrival;
...Radio Log; ...Airport Information;
...Weather Information; ...Crosswind
Information; …Descent Rate;
…Distance to Descend; …How to Get Down Now that You're There;
...The Option; ...Non-Tower
Arrivals (Opinion) ...Approach
Factors; …Why not a Shallow
Approach; …Planning Descents;
...Passengers During Instruction;
…Course Reversals; …A Poor
Arrival; ...Basics of Crosswind
Landings; ...Engine Roughness During
Descent; ...Aircraft
Control begins by Knowing Where You Are; ...
Airport
Operations ...
1. Have an airport diagram
2. Check light systems available
3. Read back all crossing and holding instructions
4. Check NOTAMS before arrival
5. Get progressive taxi instructions when in doubt.
6. Check all ways for traffic
7. Use lights
8. Clear runway immediately.
9. Use standard phraseology
Arrival
Don't takeoff until you know as much as possible about where
you are going.
Prior to every flight it is the responsibility to confirm that there are NO
temporary flight restrictions. If the flight consists of more than one
leg this
confirmation is required at the beginning of every leg. You must think
defensively. There are those both in and out of government who
consider
every light aircraft and airport an intrinsic hazard to our country's safety.
A part of your preflight that may not be a part
of your early training is preparation for your arrival. Statistics
show that inadequate preflight combined with landings, comprise
the highest cause and place factors for accidents. An arrival
produces unexpected situations and conditions that can confuse
even experienced pilots. The risk of any arrival can only be
reduced by adequate research and information.
Regardless of density altitude you always fly approach speeds
according to the POH. True airspeed and your apparent speed will
be higher the higher the density altitude. If you are a lowland
pilot, this effect can be quite disconcerting. Lean your mixture
for best performance. Landing on any unfamiliar runway of less
than 150% of the obstacle clearance distance for your aircraft
is indicative of poor judgment. The additional distance is needed
for any mistakes in judgment or performance.
You need to make an arrival information checklist to supplement
the information available from the charts and airport guides.
Abbreviate the following information on an airport card. A concise
form 2x2 inches will contain most of the information and the
other side should have a simple diagram of the airport, patterns
and beacon. Airports and their surroundings are easier to locate
when we know where to look.
Radio log
Com Nav
FSS VOR/code/radials
RADAR NDB/code
Tower
Ground
Unicom
CTAF
Airport Information
Name
Frequencies
Arrival call-up points/common/familiar/likely
Pattern entry/easy/efficient/likely
Altitude/Pattern altitude
Runway numbers available/Runway number probable
Density altitude
Wind favored runway
Runway elevation and length/required length
Lighting
Weather information
Surface winds
Ceiling
Temperature
Crosswind information
Based on expected runway and expected wind
Crosswind component Headwind component
to 30deg; off runway 1/2 velocity 3/4 velocity
to 60deg; off runway 3/4 velocity 1/2 velocity
to 90deg; off runway full velocity zero
Descent
Rate
Useless unless you make a card and use it often enough to have it as
part of your flying skills toolbox.
Altitude to Lose = fpm at 60 knots
Miles to lose it in
Now adjust for YOUR speed. If at 90 take fpm and add half.
(60 mph is a mile a minute)
Simply multiply distance to lose by 4 in a single or by 5 in
a twin. For example, if I'm at 7,500 and TPA is 1,500. I start
my descent in a 172 at (7,500-1,500) x 4 = 24 miles out.
The math part is: I'm traveling 2 miles per minute and descending
at 500 fpm
(i.e. 1/2 x 1000 fpm). This equates to a factor of 4.
A lot of calculations are more straightforward if you think in
terms of time instead of distance. If you need to lose some altitude
within five miles, think first of the time it will take you to
go five miles. It's going to take you probably three or four
minutes, depending on your ground speed. You won't know your
ground speed exactly unless you have GPS, so there's not much
point in being super accurate. Err on the conservative side and
say you've only got three minutes. You've got to lose 3000 feet
in three minutes, ergo 1000 FPM. Losing 3000 feet in 5 miles
is a pretty steep descent -- about twice as steep as a typical glide slope. If you could keep your speed down, and buy yourself
a fourth minute, you could get it done with only a 750 FPM descent.
When flying a non-precision IAP, the commonly taught method is
to make all step-down descents at a particular rate, perhaps
700-800 FPM. This rate will be steep enough to comply with the
vast majority of IAPs, and you'll know exactly how to get this
descent rate dialed in quickly for your airplane. If you arrive
at your step-down altitude early, no problem -- just level off.
"Dive and drive" as they say.
Get the time to go 5 miles at your current airspeed. If you have
an E6B or similar flight computer, that takes a second or two.
Subtract ending altitude from current altitude and divide by
the time in minutes. Set that descent rate. If it is much greater
that 500 feet per minute, expect to rattle your passengers. If
it is over 1000 feet per minute be very careful that you don't
seriously overshoot the selected altitude. An old rule of thumb
says drop a zero on your descent rate and start leveling out
that far before you reach your target altitude.
Doing it yourself:
--Decide the rate of descent you want in hundreds of feet.
--Subtract pattern altitude from present altitude.
--Drop the last two zeros and divide the hundreds of feet digit.
--The answer will be the number of minutes to your final descent
point.
Doing it yourself another way
--Rule of Thumb is five miles for every l000 feet to be lost
at 150 kts. Gives 500fpm
--Increments of 30 knots slower require 100 fpm less.
Distance
To Descend:
Useless unless you make a card and use it often enough to have it as
part of your flying skills toolbox.
1) Take your altitude and multiply it by 3. That equals your
distance in miles to begin your descent.
2) Now take half your ground speed. This is your rate of descent
in hundreds of feet. Ex. If you are
flying at 12000ft at a ground speed of 150kts and you need to
descend to 2000ft, the difference is 10000ft.
Multiply 10*3=30 miles out you must begin your descent. Half
your ground speed is 75, add a zero, and 750 ft per minute is
your rate of descent.
If you take 1/2 your airspeed add a 0, you get the fpm that gives
you 3 degrees (usual approach descent).
So at 90, 1/2 is 45, 450 fpm is 3 degree.
How to
Get Down Now that You're There
--Plan to make a cruise descent until turning downwind.
--Turn your altitude into airspeed.
--500 fpm is easy to figure flying 200 fpm is more difficult
to fly.
--Remember to adjust your power, mixture and trim every thousand
feet.
--Do not exceed Vno (Structural cruise speed) where green and
yellow meet.
--120 knot descent at 250 fpm will cover four miles for every
thousand of descent
--Slow to low cruise speed on the 45 entry into the pattern.
--Arrive a bit low so that other aircraft will be visible in
the sky backlight.
The normal approach speed of most aircraft is very close to the
Vy speed used for best rate of climb. In a descent it provides
the greatest distance traveled for each foot of altitude lost.
Speeds that are faster or slower than this Vy will increase your
rate of descent.
You would use these speeds other than Vy in a landing situation
where you are high. To a degree both will work but the slower
than Vy speed is to be preferred since you will not need to dissipate
excess airspeed in the flare. By slowing below Vy your descent
path will become steeper, but the rate of descent will slow.
The airspeed at which the minimum descent rate is obtained is
the airspeed close to Vx using the least engine power. The best
glide airspeed is the optimum lift over drag airspeed.
The Option
A landing clearance for the option will include all variations
an aircraft is capable of making from a low approach or pass
to a full stop. Between these two we have a touch-and-go, stop-and-go
and taxi back.
Non-Tower
Arrivals (Opinion)
There are several ways to enter the pattern from the other side
of the field.
1. Over fly at TPA + 500 feet. Check out traffic, runway layout,
wind, activity on the ground, construction, etc. This is an excellent
way to enter at a field you have never flown into before. After
you over fly, do NOT descend to TPA while in the airport traffic
area. Proceed at TPA + 500 well past the downwind leg of the
pattern. Stay downwind of the line perpendicular to the center point
of the runway. This will keep you hopefully clear of entering
and departing traffic. Then descent to TPA and turn to the forty-five
degree entry line to the midpoint of the downwind and proceed
with a forty-five degree entry to downwind AT TPA.
2. If you are familiar with the airport, and have the wind, you
can descend to TPA before reaching the airport. Keep a close
eye for traffic ON the runway, and make a crosswind leg over
the upwind end of the runway at TPA. Then turn onto the normal
downwind as if you were doing closed traffic. Be alert for traffic
entering the downwind from the upwind direction when you are
on your crosswind leg and from the normal forty-five degree
entry when you are on the downwind.
Any pattern entry you make should take into account the traffic
in the area and plan for appropriate spacing so that you will
neither overrun the airplane in front of you nor force the airplane
behind you to overrun you.
High Flyer
Approach
Factors
Mistakes in the approach are not singular in nature; they compound
each with others from speed, power, configuration, visual perspective,
butt/gut feeling, and control.
1. Getting your seat to the right height and locked position
is the first step. The nose position is not the same in all aircraft.
You should be able to look comfortably just under the window
and see the bottom of the wing.
2. If you are within one or two notches of the most forward seat
position and have a complete radio stack, you are near the forward
CG limit. This may require some special modification of what
you do. Individual differences require individual adaptation.
I once had to put a 60# sack of concrete into the luggage compartment
to enable a student to make a normal flare when solo. In another
situation I had the student make all landings with 1200 rpm to
improve elevator authority. Passenger in the back seat will make
the flare control easier.
3. Stabilized airspeed is vital. Work out the proper Vref for
the weight of the aircraft rather than the gross weight figure
from the POH. It could be below 55 knots. Use flaps according
to wind conditions. Do all your trimming for hands-off speed
before the round-out, two fingers in back when pulling and lifting,
maximum.
4. To get the feel of the roundout and flare practice, with instructor,
making the approach at 1400 rpm all the way to touchdown. This
requires a very smooth logarithmic movement of the yoke back
and UP along with right rudder changes (increases) as appropriate.
5. The movement of the yoke should only be back/UP or stop. Any
forward movement will be a reaction most likely to be at the
wrong time and in the wrong amount. Do not attempt to salvage
a landing. Instructors set a poor example by taking over and
doing this. If things aren't right, the go-around should be your
first and best option.
6. Do not let the ground contact jar you or your arm forward.
Lock your elbow and arm against the door. Keep the nose off as
you bring up the flaps and then add power to keep the nose off.
A touch-and-go should not need the nose wheel to touch. Be smooth
with the power and anticipate rudder application.
Why
Not a Shallow Approach?
--A good landing has a steep descent angle, exact airspeed, flare
and firm touchdown.
--A good landing is not flown into the ground, rather, it is
allowed to happen.
--A shallow approach leaves no room or opportunity for a proper
flare.
--A rule: Don't raise the nose before reaching the threshold;
don't lower the nose once past the threshold.
--A shallow approach made at 2000 rpm has only 400 rpm reserve
left for climbing when needed.
--Normal approach at 1500 rpm and steep descent has 900 rpm reserve
power to recover from turbulence.
Planning
Descents
--Turbos require more descent planning than other aircraft
--At 150 knot descent speed and rate at 500fpm multiply 5 times
thousands of feet altitude to lose. Product is number of miles
from destination to begin your descent.
--At 200 knots multiply by 6
--Another way, double the thousands of feet to lose for time
to destination altitude. Select desired ground speed to time
on E6-B for distance to start down.
Strange (Emergency) Airport Arrivals
--Over fly so you can plan where you will land when the engine
fails on takeoff.
--Pre-plan: Where am I…
Where do I go…
What's the wind…
What's to do…
Look for the OWLS
--Obstructions to avoid…Surface is three dimensional,
above, on, and below.
Obstacle height X-10 for unusable runway
--Winds (see below)
--Length of useable runway… Always consider landing
on the diagonal
--Slope: Up-slope is always better.
--Look for shadows in order to find the poles.
--Fly heading, altitude and airspeed
--A 50' obstacle takes X-10 or 500' of wasted runway when crossing
--CONCEPT of wind:
90-degree 15 knot wind for 1 hour will put you 15 n.m off course
4 minutes will put you 1-mile off course
2 minutes will put you 1/2 mile off course
1 minute will put you 1/4 mile off course.
Passengers
During Instruction
Airplanes fly differently with different loads. In my opinion
Pipers fly so differently that it is important for the
trainee to experience several gross takeoffs and landings. The
180 hp Arrow and the 260 hp Cherokee 6
were so underpowered at gross that the takeoff had to be held
in ground effect to achieve acceleration to
climb speed before initiating the climb. No way to teach this
skill appropriately without having passengers. The C-172 rotates and flares much differently with a rear seat
passenger.
Course Reversal
The distinction between a direction reversal and a course
reversal has to do with the original 'line'. A direction change
like a left/right 180 moves you off the original line. A course
reversal can be accomplished by the 45 to one side and a turn
in the opposite direction at a specific point. The problem is
finding the point.
The holding pattern is often used as a course reversal based
upon a specific airway point from which the racetrack pattern
is entered by way of a teardrop entry either left or right. On
arrival at the course intersection the initial turn is 30 degrees
to the side and after two-minutes a turn is made back to intercept
the original course line but on the reciprocal course.
In the recent past, the FAA via the AIM has relaxed the requirement
for use of the teardrop entry and now accepts the use of a course
reversal using the 80/260 method. I very much prefer using the
90/270 method which works just as well and requires far less
mental gymnastics.
To illustrate my point I will walk you through the 90/270 process. Using the headings of 360, 090, 180 and 270 all of which are in the form of a +. The seldom noticed fact is that they all add to nine. All numbers of the compass rose that are in the shape of a + one from the other. Check this out beginning with 020, 030, 040, etc. Knowing this 'sum of the digits' pattern can be quite useful in making turns of multiples of 90-degrees or 45-degrees with a manual E6-B or an ADF card.
On an initial course of 360 (3+6+0=9)we want to reverse that course. We look at the heading indicator and find that the reverse course is 180 (1+8+0=9) A teardrop hold will be either to the left or right side. To the right the 90-degree number is 090 (0+9+0=9);to the left the 90-degree number is 270 (2+7+0=9. Prior to making any course reversal you look at the heading indicator and select first the number for your initial 90-degree turn. The subsequent number at the end of the 270-degree turn is at the bottom of the heading indicator. On completion of the left/right 270, 180 will be on your nose.
A basic VOR training exercise that I use is to determine the wind direction over a VOR, I then turn the whole world until the wind is from the North. (That's an airplane joke,son.) We cross the VOR directly into the wind and at the end of two minutes initiate a 90-270 course reversal back through the VOR for two minutes to perform a second 90-270. All banks are at the same angle. I usually 30-degrees. These reversals tend to be 'perfect' because we have removed wind correction as a problem. The next part of the lesson is to do the same process crosswind and adjusting the 270 turn to intercept the desired course.
I also teach the course reversal as a part of the overfly
and pattern entry into uncontrolled airport patterns. After we
have determined the active runway by reading the windsock, we
fly an outbound 45-degree course from the runway heading and
descend toward pattern altitude. While doing this we use the
numbers on the heading indicator to select the 90-270 numbers
we will use for our inbound 45. Winds will always have some effect
but this is as good as it gets at unfamiliar uncontrolled airports.
The entire process is very
much easier if you have a heading bug and set it to the landing
runway heading.
A Poor Arrival
Date: 1996/
Two days ago, just as student and I were walking out the airport gate a pilot
went out with us. For thirty seconds he proceeded to rail against the ATC
operations used for his arrival. I had listened to his procedures and to ATC's
responses until just prior to our changing to ground. It makes a case for
knowing what you are doing when making an airport arrival.
There is a mental quirk that occurs to older people where they are unable to know things that they knew just moments before. It's called agnosia. Simply put it means that you don't know what you don't know. This pilot was suffering from an early onset of agnosia.
This pilot on his initial call-up some ten-miles east of the airport had been told to report on two-mile base. He gave an acknowledgment about reporting but failed to mention that he had no idea where the two-mile point was. He reported so late that he was in conflict with downwind traffic. ATC had him turn left to fly downwind. The traffic downwind was cleared to land. Our friendly pilot was told to turn right base to land on the left following left base traffic about to turn final. He didn't like that and requested the right. ATC said unable because of traffic on final for the right.
This pilot was unhappy with his treatment by ATC not realizing that his
poor procedure had messed up the entire airport as ATC tried to fit him into
the mix. I never cease to be amazed that so many pilots are able to survive
their own ignorance.
Gene Whitt
Basics of Crosswind
Landings
Those of us who have a generalized difficulty such as with crosswinds are
failing to see the trees because of the forest. What I'm getting at is that
every flying procedure is made up of an accumulation of basic skills.
In the beginning where and how you sit in the aircraft will determine how well
you see, what you see, and where you are able to look. The first basic is to
have the seat properly adjusted so you can get full extension of control
movement.
Next it helps if the touch on the controls is as light-fingered and
light-footed as will your stress level will allow. (Once had a student sand
his fingertips in order to increase his sensitivity.) Horses, women and
airplanes respond better when handled firmly but gently.
With the foregoing in hand, we can get to the basics. Every landing is to some
degree a composite of the cross-control requirements of the severe crosswind. Take airspeed as an
example. If your basic skill in
airspeed control is deficient you will never have any consistency in the
effects of control application. The
pressures you apply to ailerons, elevators and rudder are going to be the most
predictable if you can maintain constant airspeeds. Time spent practicing
landings is wasted until airspeed control is acquired.
Building on where we look and airspeed control we predict and anticipate the
kind and amount of control movement that will be required to accomplish a
desired result. Most flying skill uses coordination so the maneuver that
requires uncoordinated use of the controls is physically uncomfortable,
emotional contradictory and mentally confusing. We do not want to fly one wing
low, nose cocked with unusual wind noises entering the cockpit.
Now, during uncoordinated flight, all the airspeed skills fail to fall into
place. The pitot tube is not getting the direct pressures normally existing
and expected. Holding the wing low and the nose straight at a semblance of
constant airspeed has become a juggling act confusing to the mind. And,
therein lies the solution.
Get rid of an effort to think of how to fly the crosswind. The basic skill we
need is to fly uncoordinated without thinking about it. It's called the Dutch
roll. You will not learn to not-think all at once. Unlearning is often the
most difficult of learning processes. The non-pilot will take about five
three-minute sessions and the pilot only two sessions to get one good roll
then they get easier and better.
I have usually called this a 'doing what it takes' skill. You must combine all
the aileron, elevator, rudder and airspeed control skills to put the plane
where you want when you want it there. Don't think it, just do it and it will
fall into place with all your 'wants' satisfied. Take it, it doesn't happen
any place else except in making a good crosswind landing.
Gene Whitt
Engine Roughness During
Descent
Engine roughness during descent is usually corrected by mixture and prop
adjustments. However, a low power letdown can cause cylinder, valve cooling
sufficient to put extreme stress on the tappets, cam lobes, rockers and push
rods. A stuck valve takes away half of an engine's power. Head for a landing
spot. Better yet, avoid the problem by always carrying ample power in the
descent sufficient to keep the working parts warm to hot.
--Occasional mild gasping or vibrations
Plug fouling, oil/moisture in magneto, water in fuel, sticky valve lifter
--Continuous vibration without noises
Unbalance in prop, collapses lifter, plug fouled, failed engine mount
--Loud backfiring with rough shaking
Stuck exhaust valve, magneto arcing, preignition due to timing, internal
engine failure
--Popping noise
burned valves, retarded timing
--Sudden noisy engine
Failed exhaust stack or gasket
--Intermittent clattering
Common in large engines with cause unknown
--Loss of power with noises
Governor failure, muffler, impact ice or carburetor ice and turbo failure
Forms of Energy
--Different forms of energy determine where you can go and what you can do.
--Accidents are the result of a pilot’s failure to use energy in its various
form properly.
--You want to learn to make the most efficient use of the wind, altitude and
airspeed.
--When an aircraft runs out of controllable energy it becomes as
uncontrollable as a moving rock.
--The more energy available be it wind, altitude, airspeed or engine the more
options you have.
--Smoothness in creating and stopping instrument trends where desired is a
sign of excellence.
--The best computer available to the pilot for planning descents is his own
mind.
--Climb or descent is a matter of setting appropriate attitude and power.
--Power increases during long descents and must be adjusted along with
mixture.
--It is important to practice 1 and 2 hundred foot per minute descents over
longer distances.
--Flight efficiency exists when thousands of feet of altitude are used to
maintain economic airspeeds.
--One speed (Vbg) to know is the clean, power-off, and full nose up trim speed
for your aircraft.
--Every pilot needs to develop skills in estimation of visual distances along
with correcting for illusions of visibility caused by dusk and haze.
--One of the neglected knowledge skills required in airport arrivals is
magnified excessive dependence on GPS information can create problems. There
may be considerable distance difference between an ATC request for a distance
report from the end of a runway compared with GPS distances from the airport
GPS point.
--Critical items for landings are altitudes, airspeeds and configuration.
--Pilot competence is best show by how well airport adjustments are made at
unfamiliar airports under adverse wind and visibility conditions.
--Every airport arrival requires a plan that includes knowing the pattern
altitude, intervening terrain,
arrival radio procedures, wind direction and velocity possible traffic and
appropriate configuration changes. Many of these factors should be pre-planned
before departure, obtained via ATIS or FSS, and are available in the POH. Even
the best of planning must expect unanticipated changes or situations that will
require pilot initiated adjustments. Waiting for ATC may be too late.
Aircraft
Control begins by Knowing Where You Are
Recently had a new CFI email me and pose what he saw as a common
teaching deficiency and asking what he might do to avoid the situation. The
problem as he saw it was instructors were often teaching completely new skills
incorrectly. What he wanted to know was what he could do to avoid doing this.
The use of GPS in the initial teaching of airport arrivals has a weakness in that you would need to select and create waypoints some distance away from the airport that would allow planning for most appropriate runway and arrival. Use of the ‘Direct to’ GPS makes no allowance for anything other than a straight in arrival to one runway. Use of GPS has little to recommend itself for most arrivals.
Use of the GPS will inhibit acquisition of all the visual approach set-up locations and appropriate radio call-up or response.
Two studies related to knowing where you are have indicated that one out of every four automobiles is not on the road taking them to where they are going. Another found that three out of every four web searches were related to getting directions. So it would appear that a good place to start teaching student pilots the importance of thinking the right way is initial emphasis on perceptions as to where a selected few geographic identities are from present location. In California roads called north or south are more often actually east and west due to the curve of the coast line. Flying south in California will soon put you over the Pacific Ocean. Los Angeles is further east than Reno.
It is not common knowledge that there are cultures in which geographic orientation as we know it with directions and distance are undefined. Some people spend their lives unaware of what lies beyond the next town or river. They have never felt the need for knowing much beyond the immediate range of their senses. More importantly they have difficulty visualizing how appearances change under the influence of lighting, distance and angle of view. There is a wide range of skill required between looking, seeing and recognition. This is where I would start. Teach people learning to fly where they are. Teach near to far directional places between airports.
Nothing turns the mind to Jello as quickly as being lost. My first effort in teaching flying is directed toward finding where you are. I seek to familiarize the student not only with the local facility, a tower visit, a ramp walk-around and an airport diagram. I try to point out where major features are visible as well as those over the horizon. Always in flying related to airports. Every place has a name and a potential use as part of a radio communication.
Before getting into an airplane, I have discussed with the student just where we will be going and what we will be doing. After the preflight I ask the student to select a flight direction and tell me (if he can) where it will take us. I try to build as much as possible on existing knowledge while constantly expanding visual perceptions not just in the immediate airport area but in all directions. I am fortunate to teach in a beautiful region that has four distinctive mountains a few miles apart. I like to use them as sign posts. You will need to create your own signposts for the student.
As a part of every lesson I will take several breaks in the flying lesson to give the student an orientation survey that will include identification of a 360-degree spread of geographic features with emphasis on home airport location and direction. Next comes organizing the aviation words to go with the places we know
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