The document found the collision between the planes could have been prevented if the US pilots from the Legacy had not, inadvertently, put the executive jet's transponder in stand-by position, in fact, turning off the vital equipment.
The instrument would have activated a system anti-collision that would have averted any solid object on its way. The tragedy, on September 29, 2006, became at the time Brazil's worst air accident. In 2007 Brazil suffered an even worse air calamity, when an Airbus crashed on landing leaving 199 dead.
The new report mentions a series of mistakes by the American pilots and the air traffic controllers. The document tried to meticulously reenact what happened in the air in the minutes and hours before the crash, using among other elements both aircraft's black boxes and radar data.
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The Air Force Social Communication Center, informed Saturday, December 6, the final report would be shown first to the relatives of the accident's victims this coming Wednesday, December 10, in Brasília, at the Cenipa (Center for Investigation and Prevention of Aviation Accidents). The results of the inquiry, however, were leaked to daily Folha de S. Paulo, which has published its conclusion.
The Air Force is not denying the veracity of the Folha's report, but isn't confirming it either. And it is saying that it didn't find any errors of project or integration in the communication instruments (transponder and TCAS – the anticollision device) aboard the N600XL (the Legacy).
According to the Brazilian air authorities, the two American pilots, Joseph Lepore and Jan Paladino were interviewed, individually, at the NTSB (National Transportation Safety Board) headquarters in Washington, between January 29 and 31.
In their testimony, they told the Brazilian team that they did not take any intentional action that would turn off the transponder and the anticollision system of the aircraft. They also said that they didn't notice and don't remember having done anything that could have caused the interruption, accidentally, of the mentioned equipment.
On the other hand, the report determined that there is no reason to believe that the crash was caused by any deficiency in radar coverage, one factor that was mentioned in the weeks following the disaster, since there has been much criticism of the radar system implanted in Brazil, especially in the Amazon region.
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The transponder, according to the official account, was incorrectly handled by Lepore and Paladin. The mistake consisted in turning off the equipment seven minutes after the Legacy overflew Brasília. The device was turned on again only three minutes after the fatal collision, when the US pilots noticed that the transponder was in the stand-by mode.
The probe shows that the transponder remained inoperative, i.e., it didn't send any information to the Brasília's air traffic tower for 58 minutes.
The Brazilian air authority sees a succession of mistakes leading to the crash. The first error was made by the Brazilian air traffic controller in São José dos Campos, the city from where the brand new plane was making its maiden flight to the company that bought it, ExcelAire from New Jersey. That flight operator didn't give precise instructions to the US pilots and told them they should fly at 37,000 feet all the way to the Manaus Airport.
The air controllers in Brasília were also mistaken when they were unable to notice that the Legacy was not following the flight plan and had the wrong altitude. Besides, the military controller on duty also did not realize when the transponder was turned off.
Still another mistake took place when a new operator took control. The new controller was told by the colleague, who was leaving, that the Legacy was flying at 36,000 feet when in reality the executive jet was in a collision course with the Boeing, at 37,000 feet.
And once again nobody noticed that the transponder was disconnected. For 50 minutes there was no communication between the small plane and Brasília's control tower. When the Manaus control tower took over, the wrong information on the altitude was again passed along.
According to the FAB, the American pilots weren't trained enough to pilot the Legacy and also were not aware of the flight rules in Brazil. The Brazilian norms adopt the standard from the ICAO (International Civil Aviation Organization). These rules specify that the flight plan must be rigorously obeyed.
The Americans, however, used FAA's (Federal Aviation Administration) procedures, which are the ones current in the United States. These rules establish that a flight plan should be maintained until orders to the contrary from the air traffic controlling tower.
There is also information that when the pilots attempted communication with Cindacta-1, the Brasília tower, they were not heard because another aircraft in the area interfered with the connection.
The inquiry concludes that it's not its intention to point fingers and assign blame, but to establish what factors contributed to the crash in order to avoid similar tragedies in the future.
As a result of the investigations new guidelines are being suggested to the different organs linked to the civil aviation, in Brazil and abroad, to improve flight safety.
One of them proposes that the transponder be improved since it was noted that's possible to confuse data from the airplane's radio with those from the transponder itself. Moreover, the equipment can go into stand-by due to the pilot's negligence. Other recommendation is that a sound alarm be devised for airplanes and air control center that would go off when a transponder stop operating.
The reporter of a congressional inquiry about the air traffic crisis in Brazil, representative Marco Maia, from the ruling Workers Party (PT) commented that the Air Force's report conclusion once again stresses the need that Lepore and Paladino be brought to justice. Maia defends the idea that the American pilots should be held responsible criminally for the accident.