Two air traffic controllers who monitored the Legacy executive jet that collided with the Boeing 737 over the Brazilian Amazon killing all 154 people aboard talked to Brazil’s weekly magazine Época about the accident and indicated the trouble with the control tower equipment was a decisive factor in the tragedy.
Both men, who work for the Air Force as most flight controllers in Brazil, agreed to give their version of what occurred in the control tower after the Boeing 737 disappeared from the radar with the condition that they might remain anonymous.
One of them was responsible for monitoring the jet piloted by two Americans while the plane was in the Brazilian capital Brasília’s air space. í‰poca magazine calls him controller A. The other man, controller B, was working in the same room and he also witnessed his colleagues’ drama, in the afternoon of September 29.
Controller A expressly mentions a blind zone in the Amazon where the Boeing coming from Manaus to Brasília and exactly on the same path as the Legacy could not be seen:
"… The Gol flight had left Manaus’ area at 3:35 pm and should enter Brasília’s area at 3:50 pm, that is, 15 minutes later. Just time enough to cross the blind zone. It was already 5:20 pm and nothing, the aircraft still wasn’t on the radar. Then I asked the controller who was on the monitor: what happened? He said: ‘The plane hasn’t showed up and we are in contact with Manaus’.
"Before this fact everything was normal. After the aircraft’s disappearance, every one was feeling down. I saw one of the team members shaking the head, almost crying. Other supervisors asked to leave their own monitor to try to help the two supervisors. That’s when all other work regions started to concentrate on the accident zone.
"Lots of officers appeared and then we noticed that the worst had occurred. The air became tense. There were people crying and asking to leave. The supervisor asked the team who was going to take our place, at 9:30 pm to arrive earlier. The supervisors were asking people to calm down, but nobody was able to work."
Says Controller B: "One of the women controllers for the Rio de Janeiro region started to cry. Then the whole center felt touched. We needed a psychologist at that time, but no one showed up. The officers who were present didn’t know what was happening. I don’t know, maybe they didn’t want to believe. They didn’t know how to deal with the situation. There was even an argument between controllers and officers. Nobody knew what to say."
According to Controller A, people on Cindacta 1, Brasília’s control center, were sure that the Boeing and the Legacy were in different altitudes:
"The Legacy’s flight was normal. We only suspected something was wrong when the Gol’s plane disappeared. When the Legacy landed in Cachimbo (Cachimbo Air Base in the state of Pará) it informed that it was forced into an emergency landing because it had hit something. Then the controller said: ‘How come, if he was at 360 (36,000 feet)? There no way they could crash.’
"In our chart, the Legacy was at 360. In the radar presentation, it was at 360. Then people say that we and the supervisor didn’t do a thing and that the Legacy had transponder’s trouble. You know why we didn’t do a thing? Because we visualized the Legacy at 360 and not 370 (37,000 feet). As the plane had trouble in the transponder, we couldn’t get the data from the jet, but only from our system."
Controller B: "Our intention when contacting the Legacy was to warn that the transponder was down, and finish our task because the plane was going to enter an area not covered by radar and give them the next sector’s frequencies. That’s all we wanted to tell: ‘Talk to Manaus, and your equipment has trouble’. Nothing else."
The software should be blamed, says Controller B: "We get a record showing the proposed and the authorized flight level. It was this that induced the controller into error. The record showed the flight level they were at, 370. And the flight level after Brasília, 360. When the plane got to Brasília, the level that was requested showed up as authorized. This level was sent automatically to us.
"This is something converted automatically by the software. And we had called attention to this problem a long time ago. Then the software threw in our screen the requested flight level as if it were the authorized one. When this happened, what we saw was: Legacy 360, and not 370. As the secondary radar was not picking up the transponder information, the primary radar, which oscillates a lot, showed the jet at 360. I even remember that one of the controllers asked: ‘What is the Legacy’s level?’. And the other said: ‘360’. "
If they knew something was wrong it would have been easy to change the Boeing’s route, said Controller A. All they had to do was to call Manaus and ask them to tell the Boeing to change its course. "People ask, why haven’t you done this or that? Because for us everything was normal. If we put on paper all the similar situations we have faced we could write a book." And Controller B adds: "I have been in about 10 situations like this in my 13 years of experience."
They also deny the Air Force information that there was no communication problem that day. Says Controller B: "This rainy season is a chaos. If you go to Brasília’s control center now, you will see a madhouse. Cuiabá’s sector has three coverage frequencies. All of them have shortcomings. Communication is not clear. This is very dangerous. If the frequency is lacking, it doesn’t work. I cannot give instructions with echo, I cannot talk and get a truncated answer. The instruction has to be clear."
The controllers say that antennas in forest areas don’t work due to interference. The solution for them would be to do everything using satellite. As proof of the bad frequency in the area they mention a conversation of a TAM pilot the day after the accident.
Controller A reproduces the communication: "Brasília, for half an hour I have been trying to talk to you in all the frequencies, but I can’t make contact." This is there, recorded. But nobody is going to show this. They might even have erased it. Who is going to prove that it was there. The TAM pilots could. But they don’t want to talk, because even being civilians, they might be penalized by the Air Force."
Controller B says that some equipment is modern, but everything is badly cared for: "Technicians say that often the equipment works with improvised patches. When there is a problem, a technician patches a wire, some palliative thing that can cause problem any minute.
"Cindacta 1 is a shell. Whoever sees our center thinks that everything is modern, but we need investment in the main system: antennas and radars, which send information to the base. In the United States the monitors are old, but the frequencies and the antennas rarely fail."
