Page 3.42 ( 6,913)
Avoiding Other Aircraft
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Contents
Instructional Collision Avoidance;
…The Art of Avoidance; …Planning Avoidance; …Controlling
the Hazards; ...Situational Awareness;
...It's Called Imagination;
...Cockpit Management; ...Accident
Prevention;...Traffic Alert and Collision Avoidance
Systems; ...Proximity Warning
Indicator; ...Collision Avoidance Learned; ...Avoidance Checklist; ...The
Way to Use Your Eyes; ...How to
Traffic Scan; …Near Mid-Air
Collision; … Runway Incursion
is the 'Drug War' of Aviation; ...Ground
Marker System …Mid-airs
Revisited; ... Midair Collisions;
… Avoiding the Midair; … Learning to Recognize Conflicting Traffic;
…Being Situationally Aware; ...Mid-air
collisions 1977-1986; ...My Web Posting; ...Helping
Aircraft See You; ...Avoiding
Arriving Aircraft; ... Mark I Eyeball; ...Reasons
You Can't See; ...
Instructional
Collision Avoidance
When I started instructing ground school in 1968 instructional
flight instruction was a low percentage of all general aviation
midair accidents. Ten years later instructional accidents equaled
the same number of mid-airs as occurred during personal flying.
The cause/solution of this was multiple:
--The student is preoccupied with doing what he is doing.
--Students undergoing instruction do little scanning.
--Student relies on instructor to avoid aircraft.
--The instructor must get the student to scanning by teaching
scanning skills.
--Aircraft scanning must be three-dimensional not the automotive
two-dimensional.
--Students mimic the instructor
--Radar contact does not change PIC responsibility to see and
avoid.
--The volume of traffic often overwhelms ATC traffic avoidance
procedures.
--Radio communications is the best single universal aid for the
individual pilot.
--Eyes outside the cockpit is still the most reliable means of
aircraft avoidance.
The
Art of Avoidance
--The limitations of your eyes are a major weakness of the
'see and avoid' concept.
--80% of our total acquired information is via our eyesight.
--The understanding of how our vision works and does not work
makes our seeing better.
--Your eyes are vulnerable to dust, fatigue, emotion, germs,
age, alcohol and optical illusions.
--In flight vision factors are atmospheric conditions, windshield
distortion, oxygen, glare, lighting, design and most of all vagaries
of the mind.
--We see only what our mind lets us see.
--Our eyes require time to accommodate to different focal distances.
--If not focused the eyes default to no focus.
--It takes one of two seconds to accommodate to distant focus
--Once you see something you need ten more seconds to do something
about it.
--Our field of focused vision is very narrow. We visualize an
arc of 200 degrees but see less than 15 degrees.
--Motion can be perceived in the periphery of our visual field.
A plane on a collision course will not move.
--Covering the sun with your thumb was a WWI way of looking into
the sun.
--A plane just before it hits you will 'blossom' to fill the
windshield.
--Flying into the sun you can't see but 'they' can.
--Flying away from the sun you can see but 'they' can't.
--The degree of contrast between a plane and the background determines
if it can be seen.
--Your mind can cause cockpit myopia where it fails to 'see'
what your eyes are looking at.
--Pilots tend to over-estimate their visual abilities along with
everything else.
Planning Avoidance
Once on a flight the most likely cause of an emergency is
going to be related to pre-flight preparation. This may relate
to aircraft capability, maintenance, fuel, weather, or routes.
Either singly or in combination, these planning factors can combine
to create an emergency. Flight planning can control and reduce
accident probability by such things as flying airport vicinity
routes, altitudes, climbing at Vy, etc. The pilot's reasoning
process at emergency occurrence makes a big difference, saving
the airplane rates low on the important scale, survival rates
high. Have a checklist that keeps the priorities in order. Change
your mind only once. Make the most conservative response to preserve
or improve the current level of safety. No flight is so important
that it must be made.
The use of intelligence and knowledge can minimize the effects
of attitude and personality in assessing flight risk. This means
the ability to integrate knowledge, vigilance, selective attention,
risk identification, information processing and problem solving
into the processing ability of your brain. An alternate airport
is part of the plan as are engine failure and weather changes.
This planning is part of your training program. Contingency planning
applies to a particular flight. You set up with those in the
plane and those concerned on the ground an alternative contact
or plan to cope with possibilities. Tell someone at home of your
planned route, destination and alternatives. Arrange a communications
program to cover these situations and the unexpected.
All activities involve some degree of risk. Flying, due to its
multi-dimensional complexity, has more than its share. Risk can
be managed if the pilot has properly prepared for the flight
and is proficient and current in the required skills. Preparation
is mental, physical and mechanical. Proficiency requires recent
flying in aircraft type and weather conditions. 72% of pilot
accidents have occurred where pilots are not trained or current
in the conditions surrounding the accident. If you think training
is expensive and stressful, just wait until you have an accident
or a visit from the FAA.
Controlling
the Hazards
I recommend that we avoid flying at 3000' or 2500 VFR at
all times. 2850' is just as legal and safer. Practice airwork
over hilly terrain where 4250' is again both legal and safer.
Stay within gliding range of the flatlands. Avoid flying direct
to VORs. If you really wish to avoid aircraft, fly early in the
morning. This practice works fine unless you plan to cross MOAs
in Nevada. Military pilots know the advantages of morning
flights, too.
"Operation Lights On" was an FAA suggestion that landing
lights be used to improve detection between aircraft. Some aircraft
systems now have landing lights that pulse to attract attention.
During the bird migratory season the lights enable the birds
to see and avoid. During periods of low visibility the ATIS may
request that landing lights be used for airport arrivals and
departures. If you are showing a light so advise ATC when you
make your call-up. The use of strobe in daytime flying increases
you visibility by a factor of ten.
Many of the Bay Area airports now have BRITE
radar displays that allow radar location but not identification of nearby
aircraft who can accurately give their arrival location by radio. This
will greatly improve the specialists' ability to make a visual sighting.
They are starting to call aircraft 'in sight' long before they turn downwind
and may clear them as #1 to land.
Practice VOR tracking and holding patterns at 850' AGL. Use a
suitable VOR. You are much less likely to meet another airplane
that low. The VOR is more sensitive and requires more precise
flying down low. Do your airwork about 600' below the floor of
a Class B shelf that is not used as a flyway. Most pilots are
insecure in their ability and knowledge of Class B operations
to do flight operations there. This makes for fewer airplanes
in the area. Get and use radar advisories where available.
Always make 45-degree entries to uncontrolled airports. This
particular FAA recommendation has been the largest single reason
for reductions in mid-airs over the past twenty years. A common fault of the
45 entry is the failure of instructors to teach that the 45-entry is aimed at
the landing threshold and not the mid point of the runway. By doing this
the inbound aircraft will double the separation of departing traffic making
standard 45-degree departures. Draw it out and you will see the
difference..
Do not
arrive at airports via routes and altitudes that you know are
often used by other aircraft. There are many occasions when closer
to the ground can be safer. You know that departing traffic coming toward you
is climbing or at least should be. This means you will be safer down
low, sooner than later. Monitor local frequencies when following
freeways down low. The CHP flies low and slow even in marginal
conditions. When flying along roads or valleys stay on the right
side.
Cross-country flights should be at altitudes high enough to minimize
any local traffic conflicts. Don't follow airways and keep a
good lookout when crossing airways regardless of hemispheric
rule. Airways are eight miles wide and not all cross country
pilots update altimeter settings. Pilots who are insecure in
their pilotage skills tend to follow airways.
Know where the local flight schools have their practice areas.
Sierra out of Oakland likes to practice Southeast of Mt. Diablo.
There is a small legal aerobatics area East of Mt. Diablo. There
is a very busy flyway North to Northeast of Concord. It is best
to avoid this quadrant at altitudes less than 5000'. Another
busy route extends from San Jose up to CCR along 680. The preferred
altitude for this route seems to be 2500 so choose some other altitude..
Over 50% of all accidents occur because of pilot perceived time
pressures. When an individual feels time is important the brain
begins to screen the available information so as to get a desired
flight plan result rather than the safest one. The pilot becomes
so focused due to time pressure that other available options
are outside the perceptive scan.
A difficult flight decision can be avoided by making an early
decision for avoidance. When two choices appear regarding fuel,
get fuel; when two choices appear regarding weather, turn back
and avoid; when two choices regarding fatigue appear, stop and
spend the night. As part of pre-flight planning poise several
two-choice options as might occur and make your decision ahead
of time. These pre-decided selections should exist for both situations
requiring instantaneous choices such as engine failure on takeoff
as well as choices of where to eat en route.
Situational Awareness
I have always emphasized situational awareness without using
the term. Prior to every training flight I review the flight
plan and the reasons for certain procedures, altitudes, and performance
parameters. You must know where you are in the operational environment
and where others say they are. This reduces your risk but does
not eliminate it.
The pilot who is actively participating in securing his situational
awareness is spotting potential trouble before it occurs. The
people in the front seats should be involved totally with flying.
We must separate the flying from being a tour guide. Flying is
made up of practice and discipline, and requires practice a discipline
to keep flying the airplane as #1. A side conversation will make
you less aware of the flight situation. Complacency, lack of
attentiveness, and distraction is a prelude to an accident.
If you are pleased with your flying, situation, and competency,
you are most likely complacent. Fly as though you were in trouble,
worried, watched, and tested on every flight. Look for things
that are close to right without being right. Don't accept 'close'
if perfection will increase your alertness. Use of the checklist
to perform critical tasks reduces the natural tendency to become
inattentive. A little discomfort can be considered a positive
influence, especially when flying alone. Hand-flying will keep
you awake.
The more aware you are, the better your cockpit management, the
better will be your defensive flying performance. More importantly,
when your performance is up to standard you can detect the elements
of the pre-accident sequence. The accident sequence begins on
the ground, in most cases. The presence of risk may not be as
apparent but it is on the ground where risk reduction begins.
There are a number of personal stress factors, which dominate
here.
The risk of an accident or an emergency begins very slowly and
progresses cumulatively to ever increasing levels in a very orderly
sequence. The pilot's ability to recognize and interrupt the
sequence determines his ability to make an early on plan change
to break the risk sequence. Stress interferes with the reasoning
process. As the sequence develops the pilot get in over his head
without realizing it. He has failed to allow any options as they
occurred in the sequence. The unanswered multitude of questions
surrounding every flight decision you make determines your proclivity
for emergencies. In most accidents there is a sequence of events
where the pilot should realize that continuance would push the
capability envelope. This sequence most often begins with getting
into the airplane.
Situational awareness means that the pilot is knowledgeable of
the risks inherent in a given flight condition? Why is it more
desirable to initially climb at best rate rather than cruise?
When should a pilot opt to fly close to rising terrain? To what
extent should a pilot trust a tower or radar controller? What
options does the pilot have? What changes in flight procedures
are desirable under SVFR or at night? The pilots knowledge and
awareness of the real risks sets the threshold of tension onset
and thereby the decision making process. Even smart people make
dumb mistakes. Anyone can get lost; it takes an expert to stay found.
FAA Definition
The accurate perception and understanding of all the factors and
conditions within the four fundamental risk elements (recognition, evaluation,
selection,
performance) that affect safety before, during, and after the flight.
Explanation:
Knowing where you are, why you are there, how you got there and how to
get away.
It’s Called Imagination
---Yes, but it’s really situational awareness.
---Situational awareness is more than just knowing where you are.
--- Situational awareness means knowing where everything and everyone else is.
--- Situational awareness means knowing where everything fixed and moving will
be relative to you.
---ATC is playing this ‘game’ with all aircraft on the frequency and you
must play it as well.
---This three-dimensional chess requires imagination, anticipation, attention
and caution.
---Caution is displayed by your letting ATC know when your situational
awareness screen goes blank.
---You can do this in two ways over the radio:
---Ask ATC to point out unknown traffic by position and altitude
---Talk ‘beyond’ ATC by giving position and altitude in hopes the unknown
traffic get the message.
---You can practice situational awareness by reflecting on what has happened
in a past situation.
---Reflection involves thinking how something may have been done differently
or better.
---Practice reflection by visualizing an airport or pattern situation that
happened and how to make it safer.
---Some visualize better than others do but imagination will give flashes of
insight of what to do next time.
Cockpit Management
For the past twenty years there has been slow but steady
improvement in the safety of flying. Some of these improvements
have been in technology but the greatest change has been in reducing
pilot caused accidents. The pilot must establish for himself
personal minimums. He must live by them even though they may
be well above FAR, published, or POH figures. Higher personal
minimums will give more options and reduce anxiety of your flying.
Never second-guess your personal minimums.
Advise a second pilot or passenger of all the above information
on a 'nice to know' basis rather than on a 'need to know' basis.
The better informed others are the better they can monitor your
behavior and performance. Your companions are a resource of information
to be used. An informed resource is the most useful.
Accident Prevention
You are not likely to have a minor accident with an airplane.
Any repair is apt to be very expensive. The FAR's make the pilot
the ultimate responsible party. ATC instructions are 'clearances'
which leave the pilot responsible. Every flight is composed of
numerous choices and decisions. Flight safety is based on the
pilot's discrimination in selecting these choices and decisions.
The pilot who is in the most need for accident prevention training
is often the least likely to seek it. The once a week pilot often
falls victim to accidents in which proficiency has been allowed
to deteriorate to dangerous levels. 47% of the 80s-decade accidents
were the result of incorrect judgments and decisions. Safety
must be the paramount choice in making hard decisions. When in
doubt make the safe choice.
If what you do in an emergency as a pre-planned procedure you
have made the big step to avoiding the panic that kills people.
Knowing what to do should not promote a feeling of invulnerability.
We must have respect for the 'possibles" that occur in flying.
We plan every flight for the best safety. When something goes
wrong we must know decisively where to start and how to proceed.
Indecision is often worse than doing nothing. As with everything
in life, we can make a difference. Aviation safety investigations
have shown that accidents are due to a lack of basic knowledge
and flying skills, a complacency that whatever happens won't
happen to you, and entering into a flight environment that contains
flight hazards. Alone or in combination these await all of us
given sufficient time. Again, remember your life's ambition is
to be an old pilot.
All to frequently accidents are the result of a pilot's failure
to know what he is responsible for knowing about his aircraft,
its performance and systems. Just having a great deal of time
is type is no assurance of adequate knowledge. POH knowledge
should be reinforced by periodic refresher study. The first item
on any FAA investigation is as to whether the pilot knows all
he should know per FAR 91.103. You should be able to pass a blindfold
cockpit instrument, controls and systems check. You should know
the specifics for both normal and emergency operations.
Memory is the primary accident culprit. We forget or ignore those
skills and cautions we had as students. We develop a false sense
of competence. Memory is the source of common sense and good
judgment. You remember what you have learned and have been taught
about the flying factors that will keep you alive and free from
accidents. Additionally, you must be constantly immersed in the
literature of aviation in order to remain aware of the many changes
that are part of the continuum of being a competent pilot.
Traffic Alert and Collision Avoidance
Systems
TCAS uses
transponder equipped aircraft to display a plan view of aircraft
position and collision threat. It does this by predicting flight
path. Latest types tell pilot which way to go for avoidance.
There have been a few false warnings.
Proximity Warning Indicator
(PWI)
Uses strobe light indications
to display indicator lights as to give azimuth out to a range
of one mile. These lights are found on TV towers.
Collision Avoidance
Learned
Because you are inside a cockpit there are a number of inherent
factors that will make it harder for you to see another airplane.
Pilot fatigue, anoxia, a dirty windshield, cabin design, time
of day, age, stress, temperature, illusions, window distortion,
or distraction can make it more difficult for you, the pilot,
to see another aircraft.
77% of mid airs occur between overtaking aircraft from tail or side. You will most likely never see the aircraft you hit or
that hits you. Collisions are frequently caused by failure to
follow ATC avoidance instructions. The charts tend to emphasize
the element of high speed closure rates as being the hazard.
This is not so, since only 5% of the mid airs are even partially
nose to nose. The closure rate between a vast majority of midair
accident aircraft is a speed less that the cruise speed of either
aircraft. As you might expect the faster aircraft overtakes the
slower. Knowing the facts can protect you. 50% of all mid-airs
occur at less than 500' AGL. Another short 25% happen above 3000'.
92% happen in good VFR.
If you should have a view of the aircraft that you are going
to hit, it will creep slowly into view and will not appear to
move on the windshield. It is this lack of movement that makes
the aircraft so hard to see. There is a lag time of over six
seconds between looking, seeing and recognition of another aircraft
as a problem. An additional six seconds is required to put an
reaction into effect. At a 90-knot closure rate from a half-mile
you will have less that eight seconds to avoid the collision.
Not enough time. You must see the plane further away if you want
a survival chance. You are unlikely to see a plane beyond a mile
that is not moving on your windshield. In the final moments the
other aircraft will blossom to fill the entire window. You are
out of time.
The narrowness of our focused field of vision, only 10%, is a
primary limiting factor in our ability to see an airplane. If
you have not had an opportunity to focus your eyes to distance
in the past 30 seconds your focal distance may be less than 50'.
A window post that blocks from seeing with one eyes inhibits
your vision.
You do have some options. You can deliberately avoid common altitudes.
You can vary your aircraft course, attitude, and altitude. You
can make a deliberate effort to move the head forward and back.
You can know where to expect and look for other planes. You can
do much of the work of the cockpit like copying the ATIS, looking
at the charts by doing the copying and looking up near the windshield
so that you can split your visual field. Under no conditions
should you look down into your lap in a known traffic avoidance situation.. Even three seconds of instrument
scan should be a maximum. Use your lights.
Additionally, avoid those areas, routes, and altitudes that are
known to be frequented by other aircraft. Know that you have
the total responsibility to see and avoid other aircraft. If
you acknowledge an aircraft in sight that has been pointed out
by ATC, you are responsible from that point forward unless you
advise ATC that you have lost contact. Initiate your avoidance
procedure immediately, don't delay. Use a deliberate scan pattern
in 15° segments of the windshield.
If you must react, it is important that you pre-decide what you
are going to do. For example, turning tends to expose more of
your aircraft to the other aircraft and the bank increases the G-load on the
aircraft. My personal choice is to
climb since this is the best reaction with birds who fold their wings and
dive. As a reaction to aircraft the dive/ climb/choice might be best
weighted as to which mode
gives you the strongest G-load margin. Higher positive G-loads exist
over negative G-loads in aircraft construction and that would mean that diving
would be best.
Responsibility for traffic avoidance under VFR rests solely on
the pilot. ATC may or may not provide warnings. Once you acknowledge
having seen traffic to ATC the full responsibility rests with
you. Keep this traffic in sight. If you lose sight of acknowledged
traffic, advise ATC. When using radar advisories, the tendency
to relax vigilance, don't. ATC is not responsible for your collision
avoidance except when IFR and then only from IFR traffic. This
includes airport traffic patterns without radar, as well. Don't
trust ATC to have cleared the direction of a commanded turn,
takeoff or anything else. Clear areas for your safety. A clearance
lets you do something when YOU think it is safe.
Only the exceptional pilot can visually locate and identify a
traffic conflict from two miles. You are more likely to locate
that traffic if you are so familiar with the area that the direction
of where to look is known from a given pilot or ATC reference
point. If you are unable to locate a pointed out aircraft at
one mile the problem may relate to difficulty deciding where
to look for eleven o'clock, an ATC point-out error, or the relative
course movement. Any one of the three could amount to a 30-degree;
aggregate error. For this reason you must scan. You scan by moving
your head, not your eyes. You cannot see when your eyes move.
For a period of years, midair collisions have averaged in the
low twenties per year. Only half of these result in fatalities.
Half of mid-airs occur below 500' and 1/3 in the traffic pattern.
The causes of these are inherent in the visual limits of the
cockpit, the limitations of the human eye, and a concentration
of aircraft at airports and navigational facilities. Flight below
3000' has inherent dangers since most aircraft are below that
altitude much of the time. You can't see faster aircraft coming
into you from behind and above. Aircraft climbing into you from
below are more likely to see you. Fly at altitudes other than
even thousands or five-hundreds when you are below 3000' AGL.
Use radar assistance whenever it is available.
See and avoid has psychological effects decreasing visual effectiveness.
If we 'see' an aircraft called by ATC we tend to stop looking
for other aircraft. Small traffic over two-miles out will not
be seen. Large traffic can be seen out to seven miles. Outside
of one mile a pilot is unlikely to spot an aircraft. Limited
visibility really means limited ability to see.
Traffic is what you see, what you hear is advisory only. A relatively
high proportion of aircraft are not where they say they are when
communicating to ATC or otherwise. By knowing where you are at
all times, you can avoid being part of the problem. Make your
radio calls accurate as to position, altitude and intentions.
Stating your intentions is not a clearance for you to stop looking.
An altitude call is more likely to be accurate than a position
call.
The closing rate of most mid-airs is relatively slow since it
is most likely a faster aircraft merging from the rear 10-degees
off center to either side. It takes a minimum of 10 seconds for
you to spot, identify, react, and have the aircraft move. At
any merging speed over 700 knots you will not have time to move.
Any aircraft on a collision course within three miles may well
be unavoidable. Any aircraft on a collision course will be on
the horizon and appear motionless. Such an aircraft will 'blossom'
in your window at the last moment. Banking for avoidance will
be less effective than a dive or climb.
Avoidance
Checklist
--Organize your cockpit
--Clean the windows
--Follow the altitude flight rules
--Avoid crowed areas like near VORs
--Use your lights and strobes
--Keep your altimeter setting current
--Keep your visual scan coupled to your brain
--Visual complacency is a killer
--85% of preventable flight accidents are caused by deficiencies
of judgment or attitude
The way to
use your eyes
The weak link in the see and avoid system is the eye. Dust,
fatigue, feelings, illness, age, illusions, altitude, sun direction,
glare, heat, lighting, and aircraft design affect vision. The
eye has an accommodation function that enables it to change focus
from far to near and back again. Even the best of eyes take one
to two seconds to make this adjustment. If the weather or haze
is significant the eyes may be unable to focus to a distance
because there is nothing to see. You then have what is known
as 'empty-field myopia'. If one eye sees something that the other
eye cannot it gives a blurred or even rejected image to the brain.
This happens when you have one eye dominant over the other. Movement
is usually easily detected. While the eyes can get light from
over 200° or arc, they can only focus on a 10-15-degree
area. The eye can only focus while stopped. Move your eyes from
side to side and you will only get a gray blur. Thus any scan
must consist of a series of stops.
The system we practice is the one we will use. A good scan will
make nine distinctive stops across the windshield with head turns
to see to the rear at extreme left and right. Where you start
is not as important as having a systematic method of looking.
Drop the focus down and back up every third sweep to the flight
panel and every fifth time to the engine/fuel panel. You must
also move your head forward and back to see around the cabin
posts and compass. No one scan works for everyone but the block
scan that covers about nine sectors of the windshield is a good
methodology. A fixation with a two-second stop is required to
detect an existing target. You should devote 18 seconds to your
external scan for every three seconds of cockpit scan. This means
a 6 to l time difference, outside to inside.
Visual perception, as noted, is affected by many factors. An
aircraft below you on final while you are on downwind may be
lost in the mix of houses, trees and yards. Pilots tend to be
optimistic and prone to overestimation of estimates of their
visual abilities. Some people are entitled to this opinion however;
Chuck Yeager was able to detect aircraft far sooner than other
pilots of his WWII squadron were.
Scanning skill can reduce accidents that are expected by probability
to happen every year. These thirty annual mid-air accidents can
be reduced by seven or eight. We can learn to fly in those places
and in such a way to bring about this reduction. Most midair
collisions occur within five miles of an airport, below 3000'
and in clear weather. Use standard 45-degree arrivals at uncontrolled
airports. Learn to fly and practice where there are the fewest
airplanes and the most space. As a student, do not stop clicking
your eyeballs just because the instructor is aboard.
Scanning is not easy. The eye can detect movement over a 200-degree
arc. It can focus on a large aircraft at 7 miles. Outside the
fovea focus the aircraft would be visible as a 'still' target
at .7 of a mile. An aircraft on a collision course will be a
'still' aircraft with you as the target. A good visual search
is most difficult in hazy limited visibility conditions due to
'empty-field myopia'. Your eyes take only 30-40 seconds to return
to a default focus of about 10 feet. You will never see the aircraft
a .7-mile out. To re-focus your eyes you must sight on the furthest
visible object. You must re-focus every thirty seconds to maintain
distance capability. It takes about six seconds to see an airplane,
recognize as a threat and initiate avoidance action.
Visual scanning is only part of your protective cover. Listening
(scanning) to communications will make you aware of possible
conflicts before they arise, to surprise. Be where you are supposed
to be in the pattern and around airports. Learn where to look
to give yourself a greater time margin of safety. Know and avoid
instrument approach flyways especially in MVFR conditions. Practice
Dutch rolls or slight turns in climb to uncover the nose and make
'still' aircraft 'move'. Divide the windscreen into 15-degree
sectors focus on a most distant point in that sector. Watch the
ground for shadows. Aircraft shadows are larger than the aircraft.
If a fly-speck is moving across your windscreen it will miss
you The fly-speck that stays in one spot on the horizon and windscreen
is a collision about to happen.
Every turn should be preceded by a focused look on a distant
object. Be aware that some places are more prone to have traffic
than others are. Avoid the high traffic paths but be watchful
for those who may be doing the same. There are some optical illusions
that relate to nearby aircraft. An aircraft below you will appear
to be above you. While getting closer it will appear to descend
through your horizon. All the time it is straight and level below
you. Avoid the temptation to dive.
The most hazardous area is near an uncontrolled airport. Few mid-airs occur in a radar environment. However, once traffic has
been pointed out and recognized as 'in sight', all ATC responsibility
for traffic warning ceases unless you do not report the traffic in
sight. (It may be wiser not to report it in sight.) The price of flight freedom is responsibility
for avoidance. Mid airs occur most frequently below 3000 feet
and in clear skies. 50% occur below 500 feet and 33% in a traffic
pattern. The pilot's avoidance scan must not stop when arriving
at the pattern. The pattern scan must be both a visual watch
and listening watch on the radio. At controlled airports you
make a mistake if you put too much trust in ATC's ability to
keep you separated from other aircraft. Legally, ATC's responsibility
for separation only applies to ground operations. ATC may provide
assistance in the air but it doesn't need to. Once you acknowledge
seeing an aircraft, avoidance rests entirely with you.
Every radio call by another aircraft is significant. You must
learn to discriminate as to how a reported position, intention,
instruction relates to your position, intention, and instruction.
Some aircraft are not in conflict unless a change is made; others
may be in direct conflict. The pilot who does not have sufficient
competence to both fly the airplane and monitor the radio is
a hazard to himself and everyone else.
How
to Traffic Scan
--You must scan the way that is best for you.
--Use a second hand to see how often you really scan for traffic.
--Just looking out without taking the two seconds it takes to
focus is non-productive. So is staring at one spot.
--Know where to look. Clear before every turn, especially in
the pattern.
--Use S-turns for every climb and descent.
--Look below on final for every landing. The shadow you see may
not be yours.
--Make area-clearing turns before beginning maneuvers.
--Make your scan pattern extend to 60-degrees each side of center.
--Scan up and down at least ten degrees from horizontal.
--At one mile, an aircraft below you will give the illusion of
being above you.
--Strobes multiply your visibility by a factor of ten
--Be situationally aware of what is said on the radio.
--Talk on the radio giving your altitude.
Scan Patterns
--Variations of the 'block' system work best.
--Use a sequenced series of eye fixations across a 9 to 12 sections
of the windows. Two seconds per section.
--At each end at least two blocks are out the sides.
--At the end of each series give the instrument panel a sectional
scan.
Near
Mid-Air Collision
Definition:
An incident in which two airborne aircraft come within 500 feed
of one another OR when a pilot reports he has come 'too close'
to another aircraft. Only aviation collects this mode of statistics.
Classification:
Critical--where avoidance occurred only through chance.
--within 100 feet"
Potential
--where avoidance occurred because of pilot action
--within 500 feet
No hazard--where direction and/or altitude made collision unlikely
--14 percent of NMACs result in FAA enforcement
--5 percent of NMACs result in ATC controllers
--Increase in NMACs is due to improved reporting
--Majority of reported incidents involve at least one uncontrolled
VFR aircraft
--The annual average of actual airborne collisions is less than
30
--Probability of an actual airborne collision is one in two-million
--One VFR vs one IFR is most common (60%) incident
--VFR vs VFR is next at 33%
--IFR vs IFR has 7%
--Altitude reporting was not required until 1987
--16 per year = 1 per 1.6 million flight hours since 1995.
--56% have fatality
--60% of all aircraft landed safely
--All mid-airs since 1983 occurred in VFR conditions.
--Bright sunlight considered a common factor.
--88 of colliding aircraft show no signs of evasive action.
--12% did take evasive action but too late.
--Most mid-airs have slow closing speeds.
--Formation flights were 14% of mid-airs.
--Experience is not assurance of not having a midair.
--A small aircraft is recognizable at a maximum of 1.5 miles.
--This means that all the point-outs by ATC beyond that distance
are useless unless they are coming closer.
--At 1.5 miles the average closing speed of 200mph takes 25 seconds.
--Recommendation, don't bother looking, advise ATC that
you will accept a vector.
--See and Avoid has limitations as a way to reduce the midair
accident rate.
--The mid-air and G.A. accident rate has improved throughout the
years I have been flying. See, I made a difference.
--TCAS in airline sized aircraft have had dramatic reduction
of midair effects since 1978.
--Eliminated mid-airs among airliners.
Runway
Incursion is the 'Drug War' of Aviation
--Has been equated to a dog that chases parked cars.
--Human error by people are the problem
--Only if technology improves in other areas then runway incursion
will be a major cause of fatalities.
--Training to increase awareness and understanding.
--Technology to use automation to reduce the human input into
the equation.
--Procedures that take the initiative to reduce risks and potential
for error
--Signs/markings/lighting to reduce potential for error.
--Data accumulation to improve ability to learn from past experience.
--Local Solutions designed to improve the airfield and infrastructure.
--Eliminate unnecessary, unneeded, redundant, repetitive, echoic,
reiterative verbiage.
--Optimize human memory capacity
--Enhance distribution, clarity, interaction, and notification.
--Improve remediation of people involved.
Runway Incursion
Violation of FARs
ATC separation error
Area of increased occurrence
Violation of movement area without authorization
Safety Requirements
---Radio position and intentions, when in doubt STOP
---Readback all instructions completely if not exactly
---Know runway and taxiway signage and markings
---Position and hold has inherent dangers…
---Clear both directions for all crossings
---Have airport ground map
---Use aircraft lights
Ground
Marker System
Concord (Buchannan Field) CA is the first airport selected for
installation and evaluation of system.
Designed to use existing aircraft marker beacon frequency and marker beacon
common to majority of General Aviation aircraft. Airports will use
underground sensors (similar to highway sensors) to send voice messages into
cockpits of aircraft approaching sensor position. An ATC laptop computer
has a digital voice library to advise aircraft of any one of six locations on
the airport. Cooperating aircraft are asked to have their Marker volume
up and to fill out a questionnaire regarding use and effectiveness as part of
the program. Online at http://www.faa.gov/and/and500/520/Programs/GM.html
Did not work well enough to be useful.
Mid-airs
Revisited
--82 percent of mid-airs occur from the rear.
--Scanning to the front and both sides cover only l5 percent
of potential midairs.
--45 percent of accidents occur in the pattern.
--Common Situations:
--Low wing converging with high wing
--Faster aircraft overtaking slower aircraft
--On final at non-tower airport.
--Formation flying
--En route inattention
--Taxiing on to active runway
Avoidance at Non-tower airports
--Know and use proper terminology for your position relative
to airport or reference point.
--Tune, verify and use CTAF frequencies or get radar advisories.
--Make your first callup at least ten miles out and state your
arrival intentions.
--Identify the airport at the beginning and end of every transmission.
--Ask if aircraft fails to give airport name or position.
--NORDO aircraft are both common and legal.
--Slow down to give yourself more time to react.
--Check behind and below at least once on final.
--Report your destination on departure. This is much more specific
than just a pattern direction.
--Report IFR approach position by distance not fixes.
Midair
Collisions
--All air-carriers are equipped with TCAS (Traffic Alert
and Collision Avoidance Systems)
--Most MAC occur where most of planes are at airport below
500 feet.
--56 percent of MACs had fatalities
--60 percent of aircraft involved landed safely
--44 percent of the time, both planes landed safely
--80 percent of MACs occur with faster aircraft overtaking and
converging from rear
--5 percent were from directly ahead
--50% of MACs pilots had over 1500 hours of flight time
--33 percent had over 3000 hours
--35.5 of MACs involve student pilots with 22.5 percent when
solo and 28 percent with CFI aboard a plane
--No MACs have occurred in IFR conditions
Today, 10-7-03, my dumb son,
the half-Whitt that works for a living, sent me pictures of two F-18 that had
a head-on mid-air. One lost the entire fuselage forward of the
cockpit. The other lost part of one wing and part of vertical
stabilizer. Total value of the aircraft 80-million. Both landed
safely.
Avoiding
the Midair
--Avoid congested airspace
--Avoid VORs
--Don't overfly intersections or common call-up sites
--Stay away from military training routes (MTRs)
--Use strobes and flashing recognition lights
--Report your position accurately not as being over what you
can see.
--Use flight advisories when in radar covered areas
--Use recommended radio and pattern procedures at non-towered
airports
--We will continue to have the statistical probability of MACs
just don't let it happen to you
Learning
to Recognize Conflicting Traffic
--Use a scanning technique that avoids distractions, fixation
and blind spots
--Use series of fixated pauses of two seconds to allow eyes to
focus
--Divide windshield into five blocks and focus in the center
for distance
--Peripheral vision will detect motion
--10 degrees above and below horizon will detect most aircraft
with MAC potential
--Use a 20 second scan pattern with three seconds for the instruments
and 17 outside
--Vary your heading to create 'motion' in things you are trying
to detect.
--Vary your aircraft attitude and seat position to reduce structural
obstructions
--Use tinted glasses that will reduce the problems from sun and
atmospheric situations
Being Situationaly Aware
Departure
--Make all your movements based upon knowing what other aircraft,
vehicles and people are doing
--Use radio, signs, markings and lighting to orient yourself.
--At uncontrolled airports (NTA) all advisories should name airport
twice; beginning and end.
--Listen to ATC advisories issued to other aircraft inbound and
outbound
--Know and mark on diagram where you are now and draw out your
route as cleared.
--Track your route in stages based on intersections and turns
to destination
--Orally communicate with another or to yourself as progress
continues
--Do not stop on a runway, get off if you can or at least to
one side
--At NTAs make a full 360 while using the radio to advise of
taking runway, departure and route.
--Do not go into the takeoff holding position unless certain
the runway is clear
--Have someone check out the 6 o'clock to make sure no one is
landing.
--Advise frequency that you are in position and holding.
--Confirm runway by reference to compass heading
Arrival
--After landing turn clear of the runway as soon as possible.
--Do not let ATC force you into a premature turn.
--Taxi clear of the runway and across any hold bars before cleaning
up aircraft.
--An advisory at a NTA that you are clear is not needed but won't
hurt.
Mid-air Collisions
--General aviation aircraft averaged 27 per year.
--Forty percent of these ended without injury.
--Those involved in mid-air accidents were typically high-time
pilots, averaging 3,000 hours.
--1/2 of mid-airs occur in California
–Over half of mid-airs involve high wing aircraft
–Less than half of the mid-airs involve low-wing aircraft
--49% of pilots in mid air accident have below 1000 hours.
--1/2 of mid-airs occur during instructional flight
--90% occurs during day time.
My Web Posting
This entire thread seems to be totally entranced with the possible
conflict of aircraft on a heading/course. Whereas, the most likely conflict is
in altitude between IFR and VFR supposedly flying with 500 feet of FAA
separation.
Some time ago I was told that ATC figures a + - error 300 feet in blind
encoder/transponder reply.. The altimeter is likewise allowed a 75 foot + -
error. Not knowing for certain but assuming it is so. Look at the following
scenario.
If we have an IFR and a VFR flying in opposite hemispheric directions in VFR
conditions we have several possible extreme conditions. Take the first
aircraft indicating 6000 feet west bound. The second aircraft indicating 5500
feet east bound. If both the transponders and altimeters have errors to the
extreme in the opposite directions, they could still miss each other.
If the first aircraft is flying 250 lower than indicated due to accumulated
instrument error, while the other is actually flying 250 feet higher than
indicated we have only see and be seen to save the situation.
To me the probability of a midair is more likely to altitude error than
heading error. The odds of having two such aircraft with hemispheric
accumulative opposite errors in altitude sufficient to cause a midair is
unlikely but more likely than an opposite heading midair. I believe this
because the distances are matters of feet rather than miles. It takes both to
actually cause the midair so the total emphasis on course/heading is only a
part of the equation. I haven't even mentioned GPS altitude as a factor.
Gene
Helping Aircraft See You
One of my pet peeves in all uncontrolled airport departures as well as
controlled airport departures is a failure of pilots to communicate beyond the
airport and ATC. I do not like or teach straight-out, crosswind, downwind 270'
departures. Rather, I teach 'on course'.
'On course...' to a specific location is even better than a magnetic direction
since even locals have difficulty knowing the directions of their roads but do
know where the roads go. By including the words 'on course' in your departure
call you tell everyone on the frequency a line of flight as compared to the
broad brush flight areas of the pattern. At a towered airport including a
possible destination in your departure call you have 'filed' a mini-flight
plan. At an non-towered airport you have greatly reduced the 'hot' traffic
scan space for other pilots to see you. Try it, you'll like it.
With all due respect to others who disagree, I feel that pilots should
communicate their departure and arrival plans for the information of all who
may be on the frequency. I suggest using "... on course...as part of your
departure including final altitude call as being more definitive than westerly
or crosswind. I believe all calls, not at pattern altitude or on the ground,
should include altitude as well as the appropriate, level, climbing and
descending. The more help we get in finding traffic on the radio the better.
I teach my students to be suggestive rather than passive when talking with
ATC.
Avoiding Arriving Aircraft
You will be amazed the number of times you will have airplanes
slightly over and under you when you avoid all altitudes with three zeros or
those with five and two zeros whenever within 3000'
of the ground.
Another survival device I teach is related to reporting points. Never report
being at the reporting point. Fly so that you can say, "One North, South,
East or West", of the reporting point' I gave a talk to the EAA so now I
hear that a lot.
When weather is marginal, avoid the IFR approach corridors and remember in
haze anything you see is closer than you think
Just yesterday ATC had three aircraft entering on right base for 32R at
Concord. One was a C-150 that I often fly so I figured that with the Garmin
430 her reports were pretty accurate. The Piper was an unknown but in the
vicinity. We were in my 180 hp+ C-172.
At one point we were off the right wing of the 150 but unable to find it.
Never did see the Piper but knew that we were all in close proximity and
heading for the same two mile base reporting point.
Three rounds of position reports along with altitudes failed to enable us to
see the other aircraft. ATC had us on the BRITE to the right of the other
aircraft. My pilot, a CFI to be, in the right seat informed ATC that we were
making a right 360 for spacing and began the turn. when hearing no objection
from ATC.
No doubt ATC would have worked out a solution if a collision was about to
occur. I say, "Why wait for a situation to become critical before taking
the safe way out."
When we landed ATC thanked us for our cooperation which included exiting at
the first taxiway..
Mark I Eyeball
The Mark I eyeball is the most useful navigation aid when combined with the
Mark I Outside World Indicator for identification of obstacles and other
traffic.
Any object that maintains a constant relative position in relation to your eye
is something that you will hit if it is approaching. So when you are on final
approach and see an aircraft on a wide base out of the corner of your
windshield, that stays in the same place and just seems to be getting bigger,
you will have a collision on final with that airplane. If the airplane is
moving toward the center of the windshield, it is changing the angle and is
faster than you and IS in front of you. That does not give that aircraft the
right of way (you're on final) but if he doesn't see you and you see him,
avoidance is your responsibility. Just how close you'll come depends on speed
changes.
Motionless objects are harder to see than objects with relative motion, so it
isn't easy to see traffic that is most critical. To help see traffic and to
help them see you, use all your lights, bank to see into your blind spots,
don't fixate on the runway, clear the whole area. Look for shadows on the
ground, some day you may see two or even three airplane shadows near you.
Keep all your windows clean, scratch free and clear of tickets.
James H. Macklin
ATP,CFI,A&P
Reasons You Can't See
http://online.wsj.com/article/SB113590319247634291.html?mod=travel_left_column_hs
Interesting article that has application in aviation outside of security
screening. It might be a reasonably coherent explanation, for example, of why
it is so difficult to pick out another plane from ground clutter, especially
if the plane is of an unusual design.
Basically, the article discusses target-distractor similarity, where an object
is difficult to identify from distracting objects of a similar appearance in
the background, and the general problem of distractors, which make it
difficult for the eye to recognize a familiar object if it is in an unexpected
orientation or format. I think it could have particular application in
explaining why student pilots have such difficulty picking out other aircraft
or finding strange runways.
Target-distractor similarity could explain why otherwise intelligent pilots
will attempt to land at Luke AFB instead of, say Glendale even though the
pilot is familiar with both Glendale and Luke. They are not very similar, but
when distracted by roads and other ground clutter a pilot can become
temporarily disoriented. A closer example would be confusing Reid-Hillview
with other area airports.
Clutter distraction would simply mean that it is harder to recognize another
aircraft when it is flying over a cluttered background, such as an industrial
area, than when it is flying over an even cloud cover or over water. It seems
obvious, but consider what happens if you are told the aircraft is at 3:00
low, traveling in the same direction you are. You can look all over for an
airplane, but miss the Long-EZ or helicopter that ATC is seeing.
If a bag screener has difficulty recognizing a gun simply because the image is
reversed or in a different place from where he was used to looking for it,
consider the problem of the pilot who is looking for another airplane that is
"five miles out." Many pilots mis-report their position for a
variety of reasons, but as shown by studies like this that can make you almost
impossible to see.
An aircraft pulling out onto a runway for an intersection takeoff is another
case. The pilot may look in only one direction, or if he looks both ways he is
really only expecting traffic to come from one particular direction. If that
is the case, he may not see an oncoming aircraft even though it is in plain
sight. The eye sees it, but the brain does not register it. You get the same
sort of effect when pulling into an intersection with a car. You expect
traffic from the left and even if you look right you might not see a bicyclist
riding on the left hand side of the road, despite his bright yellow jersey and
florescent helmet. Even worse if he is on a sidewalk.
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