On October 31st, 1996, Disaster would strike
in Brazil’s largest city. TAM Airlines Flight 402 crashed immediately
after takeoff leading to the deaths of nearly 100 people in what became one of Brazil’s
deadliest aviation disasters and also the deadliest to involve that particular plane. So what happened? Clearly the pilots at some point of this short
flight lost control. But really, how does that happen at such a
critical phase of flight? That is what we’re going to explore today. Sao Paulo’s Congonhas Airport is a place
we have already discussed on the channel. As a recap, this airport, located in the heart
of Sao Paulo, one of the largest cities in the entire world, serves upwards of 10 million
passengers every year making it one of the busiest in Brazil. Why this airport is so interesting is despite
how busy this place can get, it is also extremely small for such traffic. The runways are notorious for their short
length. The massive urbanization that surrounded Congonhas
airport over the years left very little room for expansion. Because of this, Congonhas somewhat became
more of a regional hub than an international airport. A much larger airport at Sao Paulo exists
in the North of the city to handle its international traffic. Congonhas was at least of an ideal size for
the plane we need to discuss today, the Fokker 100. 51 of these Dutch manufactured planes found
themselves as part of the fleet for TAM airlines, one of the largest air carriers in Brazil
at the time behind Varig. TAM introduced them to their fleet from 1990
making up a large portion of their regional fleet. The Fokker 100 was developed from the earlier
built Fokker 28, which brought about its own set of issues. If one peers down the hole that is the history
of Fokker, you’ll inevitable find yourself dropping deeper and deeper into a proverbial
rabbit hole of seemingly no end… Something that is best saved for another day. The Fokker 100 itself was very popular in
Europe. 283 of them were built up until the demise
of Fokker in the late 1990s. The accident Fokker 100 of today’s discussion
was registered as PT-MRK. At the time, it had been recently painted
in special livery promoting the fact that TAM Airlines had recently won an award of
best regional airline by Air Transport World Magazine as indicated by the lettering on
the livery. On the morning of October 31st, 1996, this
plane was to fly between Sao Paulo and Recife with a stopover in Rio de Janeiro. That first leg of the trip is perhaps the
most widely travelled air route in not only the country but also the entire world with
multiple flights every hour between the two cities during peak hours. For the pilots it was a routine day. 35-year-old Captain Jose Antonio Moreno was
very well experienced in the Fokker 100 with over 3000 hours in the type. By the time of the accident he had accumulated
over 9,000 hours in total. He was joined on the flight deck by the younger
27-year-old First Officer, Ricardo Luis Gomes who was in contrast to the Captain, very new
to the plane. Some sources stating he had only been in the
cockpit of the plane for one week. Still he was an experienced pilot with over
4000 total hours logged. In the cabin of flight 402 were 89 passengers
and 4 flight attendants for 95 people on board. Leaving the gate, the Fokker plane was taxied
to the north side of the airport for a southerly departure where the plane soon lined up on
runway 17 Right. Immediately after takeoff, flight 402 would
fly over the Jabaquara suburb of Sao Paulo. The time was 8:26 as Flight 402 was cleared
for take-off. Brazil is rather open about disclosing Cockpit
Voice Recordings of air disasters in the country. Available to us today, is the cockpit voice
recording of this very short flight. I feel the best way to unpack this accident
is to run through it and breakdown how this take-off unfolded and what went wrong, as
it happened. -cvr recording-
The tone that can be heard in the recording here is an alert to signal to the pilots that
the auto-throttle was nonfunctional, we’ll come back as to why that happened soon. During a take-off, pilots need to be incredibly
attentive to their aircraft so that they can reject a take-off should something go wrong. To the pilots, what appeared to be an auto-throttle
malfunction was not that important to abort the takeoff for. It just means that the pilots would have had
to handle the throttle controls manually. -cvr recording-
The pilots continued their take-off. Having hit the V1 speed, they have effectively
committed themselves to take-off from this point, seconds later the plane would be angled
into the air. -cvr recording-
Almost immediately as the plane was less than 100 feet into the air the pilots began noticing
problems. But to unpack what those problems were we
need to understand what was happening in the rear of the plane. The Fokker 100 features a typical regional
design with its two engines mounted at the rear of the fuselage next to the tailfin. A sensor which governs the deployment of the
reverse thrust on the right side number 2 engine had begun failing intermittently. Signalling to deploy and retract. Reverse thrust comes in a multitude of different
configurations depending on the airplane. On the Fokker 100, the reverse thrust utilizes
the bucket configuration, similar to that of similarly designed planes like the DC9
or MD80. Two large buckets deploy behind the engines
to re-direct thrust forward to slow a plane down on landing. As you’d probably expect, they are not ever
supposed to be used in flight. In 1991, Lauda air flight 4 crashed shortly
after take-off from Bangkok following an uncommanded reverse thrust deployment. The disaster killed 223, highlighting just
how deadly this can be. The reason this can be dangerous is because
of how reverse thrust affects an aircraft’s aerodynamic performance. If one side is performing as normal and the
other side is producing opposing thrust, a great yawing affect can occur which could
make the plane increasingly difficult to control for pilots. For the reverse thrust to be activated, there
are multiple checks that should be met. On the Fokker 100 and other planes, sensors
that measure weight and spin on the wheels should guarantee that the reverse thrust can
only be deployed when a plane is on the ground, not in the air. This checks failed on flight 402 and the reverse
thrust for the number 2 engine was signaled to deploy. The buckets first opening and closing before
opening back up staying in the deployed position. -cvr-
In this accident, two rolling events occurred. Following the first roll after the reverse
thrust first deployed, the captain was able to bring the plane under control for a short
time, counteracting the roll with the rudder controls. There is another huge aspect to this disaster
that must now be discussed. When the Fokker 100 was designed, they brought
in an additional safety measure that dictate that should an uncommanded opening over the
reverse thrust occur, the throttle control for that engine is automatically reduced to
idle, without pilot intervention. This safety system had overridden the throttle
control, switching off the auto-throttle which explains those alerts during the take-off
roll. Indicating that that faulty sensor failed
during the take-off roll, but the commanding the reverser to deploy once the plane was
in the air. The pilots would never make a mention on the
cockpit voice recording about the fact that reverse thrust had just been deployed on their
number 2. Instead it is believed that they thought they
had an issue with their auto throttle as heard when the chimes sounded in the cockpit. The pilots were clearly confused about their
situation. Things would go from bad to much worse, as
because they thought they had an auto-throttle problem. Therefore when it was noticed that the engine
2 throttle was set to idle, the First officer increased it back up to full-power. Again the plane would respond and bring it
back down to idle automatically. It was pushed forward again by the pilots,
they misunderstood what the plane was doing. It is believed that the First Officer had
overridden that secondary safety measure by effectively breaking a cable which connects
the throttle with the reverser. The plane wanted to pull the throttle back,
the First Officer wanted to do the opposite. The cable broke from its connections from
the opposing forces of the plane and the pilot. When this occurred, the throttle stayed at
maximum thrust. In the end, when the reverse thrust buckets
were deployed to fully open, full thrust was applied to the engines creating the second
roll that the pilots would not recover from. Flight 402 rolled hard over to the right. Eventually, the nose dropped below the horizon. -cvr-
TAM Airlines flight 402, crashed into the Jabaquara suburb of Sao Paulo killing all
95 people on board. In the final moments before impact, the plane
flew over, narrowly missing a school before it crashed around here, on Luis Orsini de
Castro Street. A further four people on the ground were killed
as the crash left the neighborhood devastated, multiple homes destroyed in the disaster. TAM Airlines continued to operate the Fokker
100 for years after this accident. They introduced new pilot training to teach
pilots what to do in a case of an uncommanded reverse thrust deployment because the investigation
found out that the pilots were never trained for it. I feel having discussed another accident previously,
that this story goes a bit deeper. Fokker has had a bit of a history regarding
the deployment of reverse thrust inflight, partly involving one of its other planes,
the Fokker 50. In 1988, it was revealed to Fokker that electromagnetic
interference could send faulty information across various parts of the plane, including
that plane’s own safety system that was supposed to prevent the deployment of reverse
thrust mid-flight. Fokker sent out a Non-binding notice to airlines
recommending that this electrical fault be fixed. Because it was non-binding, it was down to
individual airlines to make this change. It was deemed the likelihood of this electrical
fault actually occurring to be so unlikely that no further action was implemented by
Fokker. That same philosophy was brought into the
Flight Training of the Fokker 100. What transpired on TAM Flight 402 was also
considered to be so unlikely that pilot training of reverse thrust deployment was not required. Those pilots that day, never trained for the
scenario that took their lives. With regards to that other Fokker plane, disaster
struck again on November 6th, 2002. Luxair Flight 9642 crashed on its approach
into Luxembourg. Pilot error compounded against an inadvertent
deployment of reverse thrust inflight. The investigation made note about that non-binding
notice that Fokker sent out to airlines following its discovery of reverse thrust failure. A fix that Luxair never enforced. 20 people lost their lives that day. If you want to learn more about that accident,
be sure to check out the video we already have on it. Fokker collapsed in 1996, actually several
months before TAM 402. The remaining planes that were constructed
were sold to airlines with improvements made to its reverse thrust mechanisms and the plane
never suffered a failure like this again. Over the years, the Fokker 100 flew in various
parts of the world but have been slowly phased out in Europe and the Americas. Most of the planes still flying today can
actually be found in Australia of all places. We are not done talking about Fokker, there
is something else we need to talk about regarding this defunct Dutch company, that is absolutely
best saved for another day. Patreon Outro
Hello everyone, thank you so much for watching. I know I am posting this on a Tuesday and
that is because this week we’re doing two videos. I guess this one being the additional one. There is still going to be another video this
weekend as normal. We do these from time to time, once every
few months there will be an extra surplus of a video in the production pipe so when
they arise, you get another video on a Tuesday. Anyway, a thanks to my Patrons as always. Their names are scrolling on the screen right
now. So if you see your name here, a massive thanks
to you for supporting the channel. If you are interested in joining the Patreon
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48 hours before it goes out publicly on YouTube. And you can join from just £1 per month. Keeping this outro short this time, I’m
off back to work trying to work out some tweaks with Train Simulator. I never wanted this rail video to take this
long but I am having to bend some of my rules to get the reconstruction for the video a
bit, anyway I’ll update you when that video gets closer to release. With all that said, I’m going to leave it
there. if you want to follow my personal twitter,
that will be in this video’s description. Thanks so much for watching and I will see
you on Saturday. Goodbye!
