The Crash of Comair Flight 5191
A worked example from the current [2006] news
using Systems
Thinking to find intervention points that can
reduce similar errors in the future.
by R. Wade Schuette
Sept 7, 2006
Background
Early Sunday morning, August 27, 2006, a commuter airliner departing Lexington,
Kentucky crashed on takeoff, killing 47 passengers and 2 crew members, and
seriously injuring the copilot.
The intended and actual paths of the plane, after departing
from the terminal area, are shown in the photograph below.
Normally, the plane would have taxied through the area
marked with the X in the photograph, taken the only available left turn, and then taken off in a southwesterly
heading, down the long runway, in blue, called "two two."
But, on this day, when they got to it, the short section of the taxiway marked
with the "X" in the photograph was barricaded with orange barricades
and flashing lights, which was not expected. The pilots would each have normally had a
copy of the airport diagram, showing the taxiway layout before the recent
construction.
Possibly not fully vigilant, probably with the runway chart memorized as a mental rule ("When you get to the end of the taxi way turn left, that's your runway") when they came to the new "end of the taxiway" produced by the barricades, the
plane took the only left turn. They turned onto the short runway ("two six"), in the picture in
red, and proceeded to accelerate for take off in an almost Westerly direction.
Commercial-aircraft runways, such as the longer runway 22,
typically have center-line lighting and edge-lighting. On Sunday morning, the center-line lighting was reported to be
out of service for runway 22 in the notices the crew would normally have read
carefully as part of their pre-flight preparation. The shorter runway, 26, was listed as closed until further notice.
The synchronized transcript and reconstructed aircraft
positions will probably be released in another week or so. The final NTSB investigative report will
probably take at least a year. The first
lawsuit has already been filed.
Even lacking final information, for educational purposes we can look at the
available information and learn a great deal about what kinds of things lead to
such accidents in general, and what might be done to prevent them.
Where the factors contributing to or leading to the
"accident" are social or system in nature, the lessons are immediately portable as well
to all other high-risk environments, including hospitals, nuclear power control
rooms, military operations, etc.
The purpose of this paper is not to assess legal
"blame", but to consider what we can learn immediately that we can
put into place, regardless who did what when in this particular case.
Student
Activity
It will really help your learning if you pause before
reading any further in the case, and
actually write down your initial impression of the answer to the
following 6 questions.
1) Why did the crew not taxi all the way
to the correct runway?
2)
If the taxiways were confusing or different from what the crew showed on
the
airport diagrams
they had used when they prepared
their
preflight, and the tower had a
ground-controller on duty,
why didn't the crew ask the
tower for assistance or a visual confirmation that they were on the correct
runway? (Both would normally be
provided if requested. Controllers often
get requests like that.)
3) Do you think the pilots noticed that
the runway they picked had no lights?
4) Once
lined up for takeoff, why did neither pilot notice that they were pointed
west instead of
southwest?
5)
Once rolling, why did neither
pilot notice crossing the lit, correct runway
as they crossed over it, which still would
have given them time to
abort the take-off safely?
7) If you were in charge of everything, what
changes would you make
so
that this kind of thing didn't happen again?
8) Much of this information was obtained from
the on-line web-site Wikipedia.
Can
you trust that?
Preliminary
Investigation - Known Facts
The flight in question, Flight 5191, was operated by Comair, a service provider to
Delta. Both Comair and Delta are in bankruptcy proceedings.
The crash took place on take-off from Kentucky's Blue Grass
airport in Lexington, with the airport
identified "KLEX".
[ Advanced student activity: Go visit that web-site and look around. ]
The information known about this case may have changed
substantially by the time you read this case.
Quoting from Wikipedia (as of September 7, 2006):
Analysis of the
cockpit voice recorder indicated the
aircraft was cleared to take off from Runway 22, a 7,003-
foot (2,135
meter) long strip
used by most airline traffic at Lexington.
[4]
Instead, after confirming "Runway two-two," Captain Jeffrey Clay
taxied onto Runway 26, an unlit secondary runway 3,500 ft (1,067 m) in length
[5]
without stopping the aircraft,
[6]
a common occurrence during light traffic periods, and turned the controls over
to First Officer James Polehinke for takeoff.
[7]
The air traffic controller in the tower was not required to maintain visual
contact with the aircraft; in fact, he was performing administrative duties at
the time and did not see the aircraft taxi to the runway.
[7]
Based upon an estimated takeoff weight of 49,087
pounds
(22,265
kg)
[8],
the manufacturer calculated a distance of 3,744 ft (1141 m) and a speed of 138
knots
(159
mph or 256
km/h) would have been needed for rotation, with
more needed for lift-off.
[9]
The
flight data recorder gave no indication either
pilot tried to abort the takeoff as the aircraft accelerated to 137 knots (158
mph or 254 km/h), Clay called for rotation,
[6]
and the aircraft sped off the end of the runway. It then crashed through the
airport boundary fence, became momentarily airborne after running up a
berm, and then collided
with trees, separating the
fuselage and
cockpit from the tail. The aircraft impacted the ground about
1000 feet (305 m) from the end of the runway,
[8]
killing most victims instantly,
[10]
and was destroyed by the resulting fire.
The discussion in the press, on TV, and on the
web generally alternated between blaming the pilots for the
"accident", and blaming the
person in the tower, who was covering both ground traffic control and air
traffic control.
[ Advanced student activity: For typical press comments, see appendix or
visit this web site: _________]
Regardless, there was generally
stunned amazement and the question on everyone's mind was "How on earth
could this happen?"
Treating that question seriously,
instead of rhetorically, is the whole
point of this case.
Here's some additional
information:
* WEATHER: The
weather conditions at the time of the accident were reported to be "light
rain" with "haze".
* TIME: The crash occurred
at about 6:05 AM Eastern Daylight
Time. According to airport
information, that would have been about
3 minutes after "civil twilight" which means the sky was still dark,
but there was just enough light to make out the outlines of buildings, etc. on
the horizon, if the weather had been clear, if your eyes were dark adapted.
* VISIBILITY: In short, it was a dark and rainy night.
No factors are known that would make it
hard for the pilots to see out their windows.
* PLANE HEADLIGHTS: no reported problems with those
We don't know from what we have how well
the lights
illuminate area to the side of the
aircraft.
* CONSTRUCTION
1) There was known
construction underway at the airport, with some work being done on taxiways and
runways, although no workers were present at 6 AM this Sunday. The runways were
being repaved, which is apparently done every 7
years.
Presumably because of the construction, power was off to many items normally on, including
the center-line lights for the long runway,
the approach lights for that runway,
the instrument approach "glide-slope" as well as the
radio-compass for that runway. All of
the lights were off entirely for the short runway. Apparently many of the taxiway lights were
out at the terminal end of the runways.
Apparently, the normally lit signs indicating what taxiway
or runway the pilots were approaching while taxiing were not lit as well.
* THE RUNWAYS
2) The intended
runway, suitable for commercial traffic, known by its true compass heading, was
"22", at about a direction of 220 degrees clockwise from true
north, which heading Southwest, away
from whatever sunrise there was.
3) Runway 22 is listed as a 7500 foot runway, 150 feet wide,
asphalt.
It normally has special instrument markings
on it, including edge lines,
two blocks
of stripes at the each end,
runway
numbers,
large markings every 500 feet
for the first 3000 feet at each end,
center-line lights, and very elaborate approach lighting
just off at the 26 end.
4) Runway 26, the
shorter runway, pointed 40 degrees to the left of runway 26, It is listed as a
75 foot wide concrete runway in poor condition. It has no instrument markings,
it normally has numbers at each on the pavement, it has no approach
lights.
8) It's not clear, but it's possible the runway
numbers "26" on the short runway itself had been similarly paved over
with asphalt.
RECENT
CHANGES IN RUNWAY LIGHTING
THE TAXIWAYS
5) In addition, due
to a significant number of non-commercial pilots entering the wrong runway
(known as "runway incursions")
at many airports, an extensive national set of signage is normally
required. This includes a large lit sign
indicating what runway this is, lit
signs indicating which taxiway this is,
and pavement markings (basically double yellow lines) indicating where
traffic should come to a complete stop before crossing, unless cleared or
pre-cleared by the ground controller in the tower. (see appendix.)
6) However, due to
the construction at the airport, it
appears that none of the taxiway lights had power, nor did the normally lit
sign identifying the runway, if it was even still in place and not moved.
7) The taxiway markings indicating the place to
stop had apparently been paved over with asphalt, and not yet repainted.
12)
If you examine the taxiway pattern,
you can see that a mental rule of thumb they
might use,
to get to the correct runway
in the first place, in the absence of any signs,
is "Stay to the right,
taxi until the taxiway ends, and that's the
correct runway."
RECENT
CHANGES IN TAXIWAYS
13) It appears, from a posting by a flight
instructor at the airport, that the taxiway to
runway 22 had been blocked or
barricaded just far of runway 26 sometime on Friday. He commented with anger and frustration that
there had not been notification that such a barricade was going to be
done.
There was no NOTAM I could find
of this change in the taxiway, described in press releases as "a minor
change in taxi patterns".
14) It turns out, from carefully looking at the
Google imagery, that the wrong runway actually is also what a normal person
would call 150 feet wide. It just
happens to have the center 75 feet marked with edge-lines, and 37.5 foot wide
"shoulders" on each side.
Also, it appears that the runway
had been repaved with asphalt, at least at that end.
THE CREW
EARLIER EVENTS
*
Last time the crew saw the airport.
15) It was reported that the crew had started the
day, at 5:15 AM, by boarding the wrong plane,
and preparing it for takeoff, which was detected by the ground crew only
when they started the auxiliary power unit (starter motor) before firing up the
main engines. The ground crew quickly
set them straight, and they moved, probably on the same ramp, to a different
plane.
THE COCKPIT and STEERING on the ground.
16) Now, we also have
another structural factor. The plane
(see Wikipedia) was equipped so that only the left-hand seat person in the
cockpit could steer the nose-wheel when taxiing. This means the captain (pilot in command)
was doing the taxiing from the left seat.
Meanwhile,
more-so
if
they were now late,
there are
high odds that the co-pilot in the right seat
was very busy, head down, eyes in the cockpit,
running through his
pre-flight check-lists.
17) But, this flight leg was going to be flown by the
co-pilot.
THE TOWER (Ground controller)
18)
Now, let's look
at the ground control.
The tower, which
FAA regulations and agreement said should have two people, only had one.
19)
And,
as is typical if there is little traffic, the
tower had simply cleared flight 5191 to take off
whenever they got to the runway and were
ready
That clearance may have even been
given while the plane was still far from the runway, possibly as soon as they
called from the gate and announced that they were ready to taxi to runway 22
for departure.
20) But, let's say he had decided to stay with the flight a
few more seconds. (The crash occurred 33 seconds after he turned away, for
reference.)
THE AIRPORT
LAYOUT
If you look closely at the airport diagram, you see that
there are two structural features that leap out, in hindsight.
a) The two runways
come together at the end, instead of near the middle (a V shape, not an X
shape). This makes the necessary
positions for takeoff easy to get wrong. In fact, see wikipedia, in 1993 a similar commercial jet took the
wrong runway, but tragedy was averted by two routes. The pilots delayed takeoff because they were
checking weather radar, and that's when they noticed the discrepancy in
direction, and, simultaneously, the tower spotted the problem, and cancelled
their clearance to take off.
b) The tower is
located so that the two take-off positions are almost exactly in the same line
of sight, which is directly across a
parking lot that probably has bright lighting.
One could imagine a tower located on the airport proper, not
off to the side, or, even, located between the two runways. From that vantage point, this accident setup would have been instantly
obviously, if the controller was looking.
But, it might be less safe because of other reasons.
In any case, a different runway layout might have averted
this accident, and a different tower location might have averted it.
INFO: now, a brief
update on what instruments are in the cockpit.
Modern aircraft use some combination of gyroscopic compass (known
affectionately as a "DG" for directional Gyro") and a GPS,
global positioning system. The GPS is
poor at giving direction unless one is motion. There is also a very low-tech, old-style
magnetic compass in every cockpit, by regulation, in case all the fancy new
stuff goes haywire.
The magnetic compass bounces around a lot when in motion, or
taxiing, or turning, or tipping when in flight, or when accelerating or slowing
down. The DG is much more stable,
rock-solid except for a slow drift (over 10's of minutes), and has only one
problem, which is relevant here: it has
no absolute zero reference point.
Every-time the plane is restarted, the electric gyro spins up and the DG
settles in to pointing some random direction, very stably.
Typically, a pilot taxis to the edge of the runway,
stops, and, if at right angles to the
runway, "sets the DG", ie,
twists the dial to make it know which way is North. Or, if the taxiway comes in
at an angle, as it often does and as it does for the bad runway, runway
26, the pilot will "taxi into
position and hold", ie, line up with the centerline exactly,
then reach over and "set the DG" to the runway
heading.
The DG has no idea what the right heading is. So, if the
pilot had believed he was on runway 26, he would have lined up on the
centerline, then "set the DG"
to read "26".
After that, he could count on the DG being correct for at
least 10 minutes, and then it would only be a few degrees off.
21) But, it is also
likely, if they were late, or under pressure from management to arrive on time
regardless of trouble, they might have
done a rolling setup - ie, turned onto the runway while accelerating, and just
set the DG as they line up with the centerline, now moving about 20 mph.
22) one could cross-check the magnetic compass as well, but
that only works if it has a chance to settle down. Due to the pressure for high-speed operation
it may never settle down. This is from
airliners.net (and I agree):
TTailSteve  From United States,
joined May 2006, 41 posts, RR: 0
Reply 50, posted Tue Aug 29 2006 14:01:06 UTC+2 and read 10499
times:
|
|
Quoting VS239 (Reply
41):
I appreciate checking the compass would not show the difference between,
for example 24L and 24R, at whichever airport has something like these but
it would tell the difference between 220 degrees and 260.
|
If they made a rolling takeoff, that is advanced the throttles as they turned
onto the runway, the compass would be useless to check. A compass is not
accurate when accelerating or decelerating. It will indicate a turn and
slightly wrong heading. A compass can only be used in stable flight. Of
course, there are other instruments that are not affected by acceleration or
deceleration that can be used to check the heading of the aircraft. However I
just wanted to point out that a compass is not accurate in these conditions.
This question is asked in many variations in every private pilot check ride
and written test.
|
22) But, in this case, the "hand-off" of control
probably occurred in an accelerating turn.
Reading the general aviation bulletin boards, other people recount how
this often happens and what it's like when the wrong runway has been selected:
Skaggs From United States,
joined Dec 2003, 129 posts, RR: 1
Reply 160, posted Wed Aug 30 2006 19:25:44 UTC+2 and read
1500 times:
|
|
I just talked to my Dad (Retired DL 777 Capt) about
this. He told me he damn near took off on a taxiway in a DC-9 years back. The
Capt. taxied it while my Dad was head down tuning radios or whatever, it was
my Dad's leg and the Capt advanced the throttles and told my Dad 'you got
it'.....They were doing 20 kts or so and my dad noticed green lights on the
centerline and shut it down. He said he didn't immediately know what was
wrong but he knew something was off.
I bet something similar happened here.
|
23) So, the magnetic
compass was effectively disabled by the decision not to pause and let it settle
down and cross check it. That was, in
turn, brought on by being a little late, and the mental frame that this was
surely the right runway.
It appears there never was any doubt that this was the right
runway, so vigilance was never triggered.
There was no "time out", as now used in operating rooms in
hospitals, to ask if there was any way that this could be the wrong patient /
wrong runway.
25) Also, in general,
the crew would have engaged their flight-director (autopilot deluxe), and set
in the instrument landing system frequency, which would be a further cross
check. But, due to the construction,
according to the NOTAM, that was also
not powered and not available.
Fact: Also, planes have no odometers. You can't measure distance driven along the
ground.
27) Also, GPS devices exist that can figure out
automatically which runway you are on, how many feet are left, and that warn
you out-loud if there is not enough runway left to complete your takeoff. However,
the versions of these that would be suitable for cars are not considered
safe for commercial aviation. (Some
private pilots take along their own unauthorized GPS anyway.) And the commercial versions, much safer
because they are fully validated, cost
$18,000.
The airline, in bankruptcy, had elected not to add these
devices to the fleet, saving $18,000 per aircraft.
INITIAL
ANALYSIS
So, there were none of the normal markings or
signs available to the pilot, due to the construction, and the end of the
correct runway had to be located and confirmed some other way.
Given subsequent events, it's
very likely that the pilot and co-pilot knew "the lights were out at this
end".
(Note, the total of the lawsuits will easily exceed
$18,000.)
28) And, if you stand way, way back, someone had decided that it "was an
acceptable risk" to continue flight operations at the airport during
construction, as opposed to just
closing it entirely until the work was done.
29) And Comair had decided it was acceptable risk to
continue commercial operations, including night operations, during
construction.
And, of course, many someones had decided that planes could safely
operate taking off in the dark in the haze / fog, with sufficient training and
instruments. That activity, once unheard of, was now considered
"routine" and the risks "acceptable."
Finally, let's look
at the take-off roll itself. The last
chance to detect that something was seriously wrong and "question the
frame", challenge the mental-model with these pesky "small"
contradictory pieces of evidence that keep annoyingly popping up.
( here we should cross-reference Karl Weick's work).
What's the pilot (left hand seat) doing? He would be staring intently inside the
cockpit at the airspeed indicator,
waiting for it to reach the speed (called "V1") at which the
control yoke could be pulled back, which would pull the nose up after a few
seconds, and the plane changed from
driving to flying. This is a trained
dance - the number 2 stares at the gauge, until he can announce
"V1". Then he looks up. For this flight, "V1" occured
about 100 feet before the end of the runway they were on, at which point they
were going something like 135 miles per hour or so. The yoke had been eased back (actually, it
wants to go back, so one just stops pushing it forward so much., but the plane
had not yet gotten the message and started to climb, when they ran out of
runway..
How about the copilot?
Well, he is staring down the runway intently, looking for deer, trucks,
or anything else unexpected to pop out of the haze. He has absolute tunnel vision, focused as he
has been trained, concentrating as he should on his single critical task,
getting down that runway safely and transitioning to flight.
(example of basketball game and woman with umbrella -
trained blindness due to trained focus.)
Still, probably with peripheral vision they notice when they
cross over the actual runway 26. Eyes stay fixated on tasks, but brain is
trying to figure out what that was that just happened. Why did lights appear
and then disappear off to the side. Can't look now.
The, runway 26 is behind them and the rest of runway 22 is
entirely dark. They can continue to
takeoff just fine, because they have headlights, but this doesn't fit their mental
model. Only the start of this runway was
supposed to be unlit.
At about this point, according to the NTSB, one voice in the cockpit comments, probably
in surprise given that they're very busy,
that there aren't any runway lights.
Now, the only way that statement makes sense is if they
expected only half the runway to be lit, as runway 26 was when they arrived 2
days earlier.
They are probably still processing it, 8 seconds later, when
the end of the runway flashes by.
Frame-challenging data tends to produce several seconds of dazed
paralysis while all the mental gyro's tumble and, metaphorically, one looks for
the new, correct interpretation of the data at hand. Several seconds uses up all their remaining
runway.
So, at this point, we
can point fingers at about 30 different people and groups, handoffs on the ground, handoffs in the
cockpit, teamwork on the ground, at the
tower, in the cockpit where multiple people tried to coordinate to do one
function that would have worked just fine if one person alone had done it.
Possible anger and rage, embodied in blind adherence to
procedures or blind but mandated breaking of procedures, effectively removed
the tower from being helpful, even 20 years later.
Multiple people could have had "It's not my job -
itis" and furthermore, proven that they were correct and not legally
liable.
Social distal decisions,
involving profit-making and work-speedup and more speedup, lurk in many
places here, each one pushing the environment towards more danger.
[ if you really want to add a new note, along the lines of
TV's CIS, it turns out that a State Senator was supposed to be on that
flight, because he was going to come
and speak to the US-Islamic friendship association (I have the cite
somewhere.). So, maybe someone wanted this flight to crash,
someone who hated Islam and Islam's friends.
That may be distracting.]
==================
Tower had cleared them:
What do we get from that?
24) And, the
controller had cleared them. Tacitly,
this means the controller had no doubt that they'd find the correct
runway. Of course, the controller knew
the correct runway had all the edge-lights on, and he would never mistake it
for a runway with no lights on. He
tacitly assumed the crew knew this. \
From the tower's vantage point, probably above the
ground-haze (which tends to form very close to the ground just at dawn), both runways were probably clearly in
view, and he could clearly see runway 22
in the distance, all lit up. In fact, it
was the only runway lit up. From his
cat-seat, there was no ambiguity, and no
risk to trigger vigilance. From the plane's point of view, runway 22 was probably just a blur in the
haze.
I believe at least one major military disaster was caused
when the commander, atop a hill, with all forces clearly in view, neglected to
inform his men, down in one valley, that the enemy was coming up the other
valley. There was a failure to see the
scene from the other party's viewpoint.
==================
SIDEBAR
This fact is rich with information
and possibilities. Here's a few, all with different meanings.
a) The crew could have been
operating at low capacity and couldn't even find the right plane that was
clearly marked.
b)
The pilot couldn't find the right plane, and they not only switched
planes, but decided it was the copilot's leg to fly.
c)
The pilot and copilot went to the plane they "always" use, but
the airport staff for COMAIR had changed things around and not notified the
crew.
Possibly, there had been a meeting
on this, and a memo, but the crew, on extended leave, missed it. This would make it a "handoff
error", as the ground staff for COMAIR thought that "everyone
knew" about the changes.
In fact, maybe there was a whole
packet of information that got dropped in handoff here, including information
about what was going to be lit when.
Maybe, due to staff cutbacks by Comair, in bankruptcy, the person who normally would have handled
that had been laid off. Maybe the person who normally handled that was feeling
put-upon and didn't feel like passing on the information.
(Is this possible? Well,
consider this: at the end of June, my wife and I flew Northwest to
Baltimore. This was in the middle of a
possible strike by airline staff, including ticket agents, etc. After we had checked in, along with many
other people, the airline cancelled the flight, as, we were told by other
flight attendants, they had done frequently lately if there weren't enough
passengers to make it profitable. Our
choices were to wait 12 hours for the next flight,
or to take a flight to DC in an
hour and somehow get from there to Baltimore.
We elected to go to DC, and
arranged to have our luggage forwarded.
Upon arrival in DC, our luggage
was nowhere to be found. About 50 other
passengers also had no luggage. The
claim-filing room was packed.
The next day, our luggage still
was not located by the Northwest. On a
hunch, we went out to the Baltimore airport, and, sure enough, there was our
luggage and what looked like 50 other persons' luggage. My wife's bag was very easy to find, because
it had distinctive polka-dots.
We asked the person at the
lost-luggage desk what was up. She gave us an earful about how busy she was,
and the fact that they kept doing this to her, but expecting her to stay at the
desk and answer the phones, and, they
were talking about cancelling her pension after all these years and, frankly,
she had not had time in the last 26 hours to check those bags in yet.
We asked if she didn't have some
sort of portable wireless scanner, such as the one Hertz used to check our car
in, in under 38 seconds. (we counted.) She laughed uproariously and said, no,
no one gave them the tools they needed to do their job.
So, as far as she was concerned,
"they" could just come check the bags in themselves. This was not
in her job description.)
In any case, the pilots got on
the wrong plane initially.
What that also means, is that
their carefully planned schedule was now wrecked. They had just lost 10 to 15
minutes checking out the wrong plane.
And, they had to hurriedly pack their belongings back into their flight
bags, possibly in haste and in the wrong order, and get over to the other
plane.
And, we don't know what else
that means. Maybe, the ground crew was laughing at this, or laughing at them,
or asked them point blank if they'd been drinking, or otherwise set a bad tone
to the morning, raising adrenaline, and possibly making it less likely that the
pilot would "ask for help" in locating the runway 30 minutes later.
This of course, plays into the
US male-gender training that it is unacceptable to ever ask for directions when
lost while driving. This is a culturally
trained norm, for some reason, and some males would reportedly spend hours on
the wrong road or get shot before they'd stop and ask for help. That does not help build a culture of open
trust and a safe environment.
====================================
All of the above may explain why flight crews have moved on
to "Threat and Error Management", where they assume that it is not
possible to perfect procedures with enough control, so instead they seek to get people out of
blind-adherence mode and back to eyes-open mode, with common sense engaged, on
top of fully-trained procedural knowledge.
In other words, people are trained to spot "small" things
wrong and amplify them instead of suppress them, as the possible single warning
that the whole model and frame is wrong.
The military (Army at least) is adopting that, judging from the Center for Army Leadership's The
U.S. Army Leadership Field Manual, McGraw Hill, 2004.
Missing cites can be found by using the Blogger (google)
search window at the top
Crash articles can be found with keywords "5191", "crash"
or "KLEX".
Supplemental materials for The Case of Comair Flight 5191
===========================================
M.C. Escher "waterfall", illustrating a
"system" where everything checks out perfectly in any local area
(except for "insignificant errors"), but there is still a global
(system) problem that needs to be detected.
(image above from
used without permission)
larger size view
Many details, but in particular look at the
"interactive runway map", which
is a Google map view, and zoom down to examine the taxiway
section
and actual runway widths and markings (prior to construction).
(used without permission)
WLEX-TV
Despite the wet weather, plans to reopen the main runway
at Lexington's Blue Grass Airport went smoothly Sunday. Just after 6 p.m., the
first jet touched down without a hitch.
Over the weekend the airport had been completely shut
down to commercial and private jets, as some 350 workers managed to repave the
seven-thousand foot runway in just two days. The work, marks the end of a $35
million runway safety project that began back in 2003.
The runway is typically shut down and repaved only once
every 12 years. So when airport officials saw Sunday's bad weather bearing down
they kept a close eye on the sky. "The weather is obviously very crucial
for us in order to get this project done and we were lucky. By the time it
started raining we had most of the runway already repaved. So the large portion
of the project had already been completed before the bad weather hit."
Said airport spokesperson Amy Caudil.
As early as Sunday afternoon there were signs that the
airport was returning to normal. As passengers began to check-in again, work
crews made some final checks on the runway.
Airport officials also say they certainly lost money
with no air traffic for two days, however they're not saying exactly how much.
Travelers who need to check on their flight times can
call the Lexington Blue Grass Airport at; 425-3114.
WLEX-TV
(AP) -- Workers at Lexington's Blue Grass Airport have
put up large 'X' warning signs at both ends of runway 26 to let pilots know the
runway is closed.
Airport spokesman Brian Ellestad says the signs were put
up Tuesday morning as a precaution. The runway has been closed since Sunday,
when Comair Flight 5191 crashed just past the end of the runway shortly after
takeoff. 49 people died in the crash. Only one person survived.
...
FAA official airport diagram
Wikipedia Entry on Blue-Grass Airport (with links to many views,
including TerraServer zoom-able satellite imagery)
(via that site, link to AirNav.com, which has sunrise and
sunset times
and link to NOTAMS )
EX BLUE GRASS
6/8333 - FI/T LEXINGTON/BLUEGRASS, LEXINGTON, KY. TAKE-OFF
MINIMUMS AND (OBSTACLE) DEPARTURE PROCEDURES. TAKE-OFF MINIMUMS: RWY 8 NA. WIE
UNTIL UFN
6/8332 - FI/T LEXINGTON/BLUEGRASS, LEXINGTON, KY. RNAV (GPS) RWY
8, ORIG... RNAV (GPS) RWY 26, ORIG... LNAV MDA NA. CIRCLING TO RWY 8/26 NA. WIE
UNTIL UFN
6/8331 - FI/T LEXINGTON/BLUEGRASS, LEXINGTON, KY. VOR OR GPS-A,
AMDT 8A... ILS RWY 22, AMDT 19... RNAV (GPS) RWY 22, ORIG... ILS RWY 4, AMDT
16... RNAV (GPS) RWY 4, ORIG... CIRCLING TO RWY 8/26 NA. WIE UNTIL UFN
6/6992 - FI/T BLUE GRASS, LEXINGTON, KY. ILS RWY 4 AMDT 16 ...
AIRPORT ELEVATION 979. TERMINAL ROUTE FROM HYK VORTAC TO BLAYD LOM (IAF)
MINIMUM ALTITUDE 2600. TERMINAL ROUTE FROM SAAPP/HYK 15.3 DME TO BLAYD LOM
MINIMUM ALTITUDE 2200. MINIMUM ALTITUDE AT BLAYD LOM (FAF) 2200. GLIDE SLOPE
3.00 DEGREES. GS ALT AT OM 2045. DISREGARD ALL REFERENCES TO MIDDLE MARKER.
DISTANCE FAF TO MAP 3.25 NM. DISTANCE FAF TO THLD 3.25 NM. TIME/DIST TABLE: 60=3:15
90=2:10 120=1:38 150=1:18 180=1.05. MISSED APPROACH: CLIMB TO 2000, THEN
CLIMBING RIGHT TURN TO 3100 DIRECT HYK VORTAC AND HOLD, CONTINUE CLIMB IN HOLD
TO 3100. S-ILS 4: VISIBILITY RVR 4000 ALL CATS. S-LOC 4: VISIBILITY RVR 4000
ALL CATS. CIRCLING: HAA 441 CAT A, HAA 461 CAT B/C, HAA 561 CAT D. INOPERATIVE
TABLE DOES NOT APPLY TO S-ILS. FOR INOPERATIVE MALSR INCREASE S-LOC ALL CATS,
VISIBILITY TO RVR 5000. VISIBILITY REDUCTION BY HELICOPTERS NA. DISREGARD NOTE:
ADF OR DME REQUIRED. WIE UNTIL UFN
4/1897 - FI/T BLUE GRASS, LEXINGTON, KY. VOR OR GPS-A AMDT 8A ....
CIRCLING MINIMUMS: MDA 1580/HAA 601 ALL CATS. VIS CAT C 1 3/4. ALTITUDE AT HYK
5.00 DME 1580. TEMPORARY FAS CONTROLLING OBSTACLE 1240 MSL/205 AGL TOWER AT 380007.65N-0843132.58W
WIE UNTIL UFN
10/041 - CLEGG ONE ARRIVAL... LOUISVILLE TRANSITION (IIU.CLEGG1)
PROCEDURE NOT AUTHORIZED. 27 OCT 09:01 UNTIL UFN
08/037 - TOWER 1138 (280 AGL) 16 SW LGTS OTS (ASR 1229868) WIE
UNTIL 14 SEP 01:22
08/035 - 8/26 CLSD
WIE UNTIL UFN
08/024 - 4/22 ASDA 7003 TORA 7003 TODA 7003 LDA 6603 20 AUG 22:00
UNTIL UFN
08/023 - 22 ILS GP OTS 18 AUG 13:30 UNTIL
UFN
08/007 - 4/22 RCLL OTS WIE UNTIL UFN
08/005 - 4 ALS OTS WIE UNTIL UFN
07/013 - 4 TDZ LGT OTS WIE UNTIL UFN
01/030 - 4
MALSR CMSN 31 JAN 15:45 UNTIL UFN
For translations in general, see
For translation in specific (from the writer's weblog,
Systems Thinking in Public Health,
posting " Comair 5191 as a "handoff" problem,
Translations: (
http://www.geocities.com/cfidarren/r-notams.htm
)
8/26 is the short runway. CLSD = closed
WIE = from right now ("with immediate effect")
UFN = until further notice.
4/22 is the long runway.
ILS = instrument landing service
RCLL = runway center line lighting
TDZ = touchdown zone
LGT = lighting
08/035 - 8/26 CLSD WIE UNTIL UFN
08/023 - 22 ILS GP OTS 18 AUG 13:30 UNTIL UFN
08/007 - 4/22 RCLL OTS WIE UNTIL UFN
08/005 - 4 ALS OTS WIE UNTIL UFN
07/013 - 4 TDZ LGT OTS WIE UNTIL UFN
So, in English:
runway 8/86 - the short one, the one you don't want, is closed.
the instrument landing system for the your runway
approached from the northeast is out.
Your runway centerline lights are out
Your runway approach lights from southwest are out
Now, what is NOT stated here are things like:
There is a lot of construction.
Ground traffic patterns have been rearranged.
Carrier gate assignments have been rearranged.
And most of all, there is no graphic, no map, no
picture showing, at a glance, what lights are lit
and what lights are out.
And, there is no notice that the RUNWAY IDENTIFIER signs
for ground taxi purposes are NOT LIT.
Much of that information is implicit, tacit, or something that might
come from a voice briefing.
Miscellaneous Commentary
from the writer's weblog,
Systems Thinking in Public Health,
1) Threat and
Error Management (TEM) and the BMJ series relating this to hospital safety
Univ of Texas Threat and Error Management (TEM)-- Airlines
now use TEM and there's some cross-over into hospital settings.
BMJpaper,
BMJ slideshow ,
aircraft pilot comments from KLEX discussion follow.
From BMJ
Error results from physiological and psychological
limitations of humans.2 Causes of error include fatigue, workload, and fear as
well as cognitive overload, poor interpersonal communications, imperfect
information processing, and flawed decision making.3 In both aviation and
medicine, teamwork is required, and team error can be defined as action or
inaction leading to deviation from team or organisational intentions. Aviation
increasingly uses error management strategies to improve safety. Error
management is based on understanding the nature and extent of error, changing
the conditions that induce error, determining behaviours that prevent or
mitigate error, and training personnel in their use.4 Though recognising that
operating theatres are not cockpits, I describe approaches that may help
improve patient safety.
The perfect vehicle for this is a new concept, new in the
last 3 years, called "Threat and Error Management." Prior to TEM
training focused on never making mistakes in the cockpit.
While in a utopian world this would be great, it is just not possible. There is
too much going on in a modern (or old) jet transport. Mistakes happen. TEM
acknowledges this by saying mistakes and threats are going to happen. It tries
to change the way we think in the cockpit by taking more of a big picture
outlook on what is going on, slowing down what we do, and communicating concerns
to find threats and errors before they cause a violation, incident, or
accident. Robert Sumwalt, Vice Chairman of the NTSB, has been a huge supporter
of TEM and has been promoting it for years at various carriers and industry
working groups across the country. Many airlines have recently included it into
their recurrent training programs. TEM is still evolving and I think is the
perfect vehicle for teaching confirmation bias avoidance.
727forever
2) Six sigma is dead! Long live six sigma!
3) Zen thought for reframing this
whole issue of context sensitivity
They said, "You have a blue guitar,
You do not play things as they are."
The man replied, "Things as they are
Are changed upon the blue guitar."
from Wallace Stevens,
The
Man with the Blue Guitar
Recommended further study:
( A brief tribute to U of Michigan's
John Gall, MD, and
his must-read marvelous book
Systemantics
- How things Fail )
http://cscwteam.blogspot.com/2006/09/failure-is-perhaps-our-most-taboo.html
"At the very least it is hoped that this little book may serve as a
warning to those who read it, thus helping to counter the headlong rush into
Systemism that characterizes our age...
SYSTEMISM n. 1. The state of mindless belief in Systems; the belief that
Systems can be made to function to achieve desired goals. 2. The state of being
immersed in Systems; the state of being a Systems-person."
(John Gall, "
Systemantics
- How Systems Really Work and How they Fail.)
Systems-functions are not the
result of human intransigence. We take it as given that people are generally
doing the very best they know how. Our point, repeatedly stressed in this text,
is that Systems operate according to Laws of Nature, and that Laws of Nature
are not suspended to accommodate our human shortcomings. There is no alternative
but to learning How Systems Work... Whoever does not study the Laws of
Systemantics and learn them that way is destined to learn them the hard way...
S. Freud, in his great work on the Psychopathology of Everyday Life, directed
attention to the lapses, failures, and mishaps resulting from forces operating
within the individual. We, on the other hand, are intestesed in those lapses,
failures, and mishaps that are attributable to the (mal)functioning of the
Systems surrounding the individual, wihtin which the individual is immersed,
and with which he or she must interact and attempt to cope in everyday life.
Specifically, we are interested, not in the process of forgetting to mail a
letter, but in the Post Office Box that is too full to accept the letter.
=================================================
FAA website on "runway incursions"
RECOMMENDED:
FAA
Flash presentation and learning tool on Runway Incursions (in general)
=================================================
Passenger list (still partial) and tributes to those killed in flight #5191,
in the hope that we learn something from all this and make their deaths at
least mean something for the rest of us.
http://www.bluegrassreport.com/bluegrass_politics/2006/08/tribute_open_th.html
====================================================
(someone else posted this, cite not instantly available. It shows what might
have been in the NOTAM, but wasn't)
FlightAware's
airport
information page for Houston Hobby (KHOU). The remark reads:
"DUE TO COMPLEX RY CONFIGURATION;
WHEN TAXIING TO THRS 12L & 12R AND 17
CHECK COMPASS HEADING BEFORE DEPARTING."
No similar information is available for Lexington airport.
That's the kind of rule one
can give one's own internal "autopilot" in order to move attention to
other tasks. Pilots are trained to
heavily on autopilots to manage tasks so they can attend to other issues.
However, if the taxiway really was blocked just at the
far edge of runway 22, then unthinking application of the mental autopilot rule
"go until you can't go any further, and that's the runway" would have
resulted in the pilot ending up selecting runway 26 and lining up on the center-line
in preparation for take-off.
Both pilots were familiar with the airport (as it
used to be) and, in this case, that familiarity and comfort level with an
internal rule of thumb might have contributed to the accident by reducing
vigilance.
So, at this point,
there are a number of factors all adding up to mislead the pilots,
remove all their familiar landmarks, mentally frame them with the wrong frame,
in which they "knew" there were no edge-lights on the runway they
desired, and getting them headed towards lining up on the wrong runway.
So, the tasks of taxiing
into position, getting set to roll, and taking off had been divided among two
team members, which now required seamless coordination instead of all being in
one person's head.
This
was forced by the design of the
nose-wheel steering of the aircraft, combined with the absolute norm-busting
inconceivable restriction against the co-pilot simply sitting in the left-hand
seat for the flight so that less coordination would be required during this
handoff operation.
This is a residual of the
air traffic controller strike that Ronald Reagan solved by firing people, which
is still rippling through the system.
Also, due to the desire of the FAA to save money and treat controllers
as powerless (? not a neutral point of view?),
the fact that the lone controller had only had 2 hours of sleep in the
last 24 hours was not in violation of regulations.
Here we have additional
behaviors of teams that are induced, structurally, by the desire to fly more
aircraft through airports than they were designed for. (In fact, John Gall mentions and I can
believe it but haven't checked, that at one point the controllers had a
job-action by slowing down traffic and clogging the system by actually
following the regulations, instead of cheating as their supervisors had forced
them to do normally.)
In
any case, having cleared the flight (the 3rd one of that morning), and seen it
was near the right location, the tower
controller turned away to do paperwork.
(Possibly, he was filling out some mandatory statistical report required
to help make the airways safer.)
He
certainly could have "stayed with" flight 5191 another 15 seconds,
but didn't. That's a whole study in itself.
One can imagine controllers trying to be helpful, and being told that
they are stepping outside their job description, which is slowing down
production, and not letting the pilots learn how to take responsibility for the
pilots' jobs. One can imagine a memo
going out, a clear directive, that controllers are, under no circumstances, to
delay, but, having given a clearance, must move on to their next task within
their own job description. The controller
might have thought "I could, but it's not my job, and every time I do that
I get punished."
