Terror in the Brazilian sky
© P.Acheffe 2006
This could be the scenario of a movie, the movie of the horrible crash
which killed 154 persons aboard flight Gol 1907, but
the described events, the human and equipments behavior are pure fiction. The
police and administration inquiries are still on the run and no evidence has
been released. Although, in order to make that narration more realistic, the
technical data related to both flights (route, takeoff time) are as released by
the media, the full timing has been obtained using Microsoft ® Flight Simulator
2004 ®.
Map and timing :
http://gol1907.pfiquet.be/manaus2.htm
Setting up
On
Sao José dos Campos « Professor Urbano Ernesto Stumpf » airport, 44 NM N-E of Sao Paolo, the Jet
Legacy 600 crew is preparing to take the ownership of his new baby while the owning
company managers are still at the (ending)
manufacturer’s party.
For
that maiden flight, the N600XL will bring these gentlemen (two managers from
the owning company, two managers from the manufacturer and one U.S columnist
who was visiting the assembly plant and has been invited to joint them for his
return flight) to Manaus where they will spend the night in order to take
advantage, the next morning, of the wonderful spectacle offered by the sunrise over
the Amazon river. Then, they will fly back to the
In
accordance with the regional rules, that flight plan calls for departure
through the PCL beacon located 92 NM away from Sao Jose where they will track
the UW2 jetway to Brasilia, heading 005, flight level
370 (37000 ft). When flying over the
By
14:15, everyone prepares for boarding, exchanging lots of handshakes and
congratulations while the pilots go through the check-lists, for the last time with
the manufacturer’s chief pilot. These two guys are no « rookies »,
the captain, 20 years as a commercial pilot with over 8000 hrs (400 on
aircrafts of the Legacy family), and the copilot, 10 years as a professional
pilot and over 6400 hrs, have total
respect and confidence from their employers.
At
14:30, the door is closed and the startup procedure begins. The copilot
requests the flight plan clearance then the clearance to taxi to the active
runway, which today is the 33.
It
is 14:47, at the runway 33 holding point, the Legacy waits for a military C130
to clear the runway, and at 14:50, the pilots, one hand over the other as per
the procedures, push the throttle levers forward.
At
the same moment, in Manaus where it is only 13:50, another crew climbs the
stairs to the Gol airlines brand new Boeing 737-800
PR-GTD (delivered 12 days earlier), in order to prepare for the flight 1907 to
Brasilia which they are expected to reach at 18:12 (eastern time, the time zone
limit being crossed at the Xingu river point NABOL), then to Rio de Janeiro.
The
two pilots start their check-list while the cabin crew hurries up securing the containers
just delivered by the catering company; down there, inside the airport, the 148
passengers are called for boarding, there is no time to loose.
« Passengers
for flight Gol 1907 bound to
Among them are many commuters using that
flight every week for their job, but there also are a few tourists, for example
these twelve retired guys who spent a week fishing uncommon species in the Amazon
river, and are discussing about the stories they will tell their relatives once
back home, the poor men cannot imagine that the fishes, carefully packed in isothermal
bags in the luggage compartment will end up rotten a few miles From the Xingu
river.
One thousand four hundred miles to the south,
it is 14:57, the Legacy N600XL leaves Sao Jose
departure to join
On flight 1907, the passengers are now
comfortably installed, doors are locked, the copilot requests the flight plan
confirmation, then the taxi clearance. The jet engines are started while a
truck pushes the plane out of the gate area.
The
pilots may then drive the 737 to the runway 10 holding point.
First problems
15h29, 187 NM before Brasilia, the Legacy
enters a new control area and is instructed to switch to 128.5 Mhz, while in Manaus, 6 minutes later, the Gol 737 accelerated for takeoff.
15h45, the Legacy is 52 NM, or 6.5 minutes for
-Brasilia
control from November six zero zero X-ray Lima bound
to Manaus, request clearance to descend to flight level three six zero.
-Zero
X-ray
-Maintain
thee seven zero, will report overhead BRS, Zero X-ray
Then, a few seconds later:
-Zero
X-ray
-Squawk
zéro four four one, Zéro X-ray
And that’s where the whole tragedy starts. The
copilot, as he sets the new squawk code, discuss with the pilot to try and
understand why they were denied the change to FL360 and take some time to
validate the new code. Since he is a newcomer on jet aircrafts, he does not know
that the radio equipment he is using may be defective. On September 12, the FAA
has issued a note requesting that the radio module be changed within a given
period of time and that, in the meantime, it is mandatory to make sure that a
squawk code be validated within 5 seconds to avoid the risk that the whole
radio unit, including the transponder and the TCAS (anti-collision system)
switches to standby mode with no possibility for the pilot to notice that
switching.
From now on, the Legacy is mute and deaf.
As they fly over the BRS beacon, the copilot
calls the controller as requested but receives no answer. He tries on the
second radio set (COM2), no more answer. The two pilots check the radio panel,
seems all right; they discuss, try to find reasons for that lack of answer and
decide to stay on FL370 as instructed 10 minutes earlier, until further
notification.
It is 15:56, the Legacy heads to 334 on the
UZ6 jetway. Normally, with
that heading, they should fly an “even” level
but since the controller said to maintain 370 ……
On the opposite way, the 737 reaches 37000 ft
at 15:05 (16:05 for the Legacy), they are 72 NM before VIBOT. In the cabin, the
four attendants have prepared the carts and start the drinks service. Of
course, Gol being a low cost company, added to the
fact that flight time is 3 to 6 PM, there is no food service.
A 15:18(western time), while the 737 pilot
switches the radio to 123.9, the Brasilia controller seeing that the Legacy
approaches the limit of his area, calls to notify the frequency change to the pilots.
Despite several tentatives with no answer, he transfers
the flight information to his colleague in charge of the next area.
Nobody seems to really worry since the radar
spot is excellent. Of course there is no more squawk code, no altitude
information on the screen, but according to the flight plan, they should be on
FL360. The new controller tries again to notify that small problem, to the
Legacy but since they don’t answer….
16:23, the Legacy flies over TERES where they
should climb to FL380 according to flight plan, but with no radio contact, the
pilot decides to maintain FL370.
16:46, flying overhead NABOL and
consequently, entering the same control area as the 737 which is in front of them
at a distance of 140 NM, and again, no one seems to worry, the two aircrafts
are not supposed to be at the same level, they are equipped with a TCAS, the
Boeing crew has been warned of the potential risk, but as long as the TCAS
gives no signal…. In addition, it would be exceptional that the two aircrafts
be exactly at the same altitude and on the very same track; those equipments
are not accurate by a few yards.
Would you bet ?
The tragedy
A 15:55
local, (16:55 in
The copilot sets the transponder to “7700”
(emergency code) and therefore reestablishes the radio circuit for the landing
procedure.
Inside the Boeing, the pilots give regularly
a glance over the instrument panel, just in case, but since the TCAS stays mute….
The
problem is that as the Legacy radio module is on standby, it does not emit any
signal and of course, the 737 TCAS cannot see it.
Suddenly, a small thing appears far ahead,
just a small bright spot, but growing very rapidly. Within a few seconds, just
enough for the Gol crew to understand what happens
and to switch the autopilot « off », with a cumulated aircrafts speed
of one nautical mille every 1.5 second, the two planes are face to face, the
pilots try to escape to the upper right, but it is too late ! The Legacy
winglet strikes the Boeing left wing leading edge while the 737 winglet skims
the Legacy horizontal stabilizer.
See http://www.pfiquet.be/n600xl.jpg
The 737 enters a spin, the pilots push on the
yoke and the pedals to try and stop the spin, they lower the gear and the flaps
to slow it down but this creates so much stress in the structures that the left
wing, weakened by the collision, breaks and hits the vertical stabilizer. The shock is
so hard that the rear structure of the body starts
cracking and finally rips
of. Nothing else can be done, the 737 is totaly
out of control. In less than two minutes, the pieces of the aircraft reach the
Amazonian forest, spread over a 10 NM
diameter area.
I will not be sad towards those who have lost
a beloved one in the tragedy and try and describe what those two minutes have
been in the cabin.
I hope they accept the idea that two minutes
is a very long time as you wait for something to happen and do nothing, but it
is so short when you are part of the event and think at what you can do to save
yourself.
see the
translation of the official inquiry preliminary report at :
http://gol1907.pfiquet.be/Golreport.ppt
see
also
http://histoiresdavions.skynetblogs.be