Airport Authority Chief Says Legacy's Transponder Was Inactive

Did the American pilots of an Embraer Legacy 600 suspected of clipping a Gol Airlines 737 last week disobey an ATC directive? That's a question for investigators of the fatal crash that killed all 155 persons onboard the airliner... and while they look into the accident, a Brazilian judge has ordered the pilots' passports seized.

Brazil's O Globo claims pilot Joseph Lepore and co-pilot Jan Paladino remained at 37,000 feet after a controller told them to descend to FL360. The Gol 737 was also cruising at 37,000 feet when, authorities suspect, the two aircraft collided... and the 737 plunged into the Amazon jungle. So far, rescue personnel scouring the jungle around the crash site have found no survivors.

As Aero-News reported, the Legacy made a safe emergency landing at a Brazilian military base following the suspected collision. Both pilots report they never saw what hit their aircraft -- only a shadow just as something collided with the jet's left wing.

ICAO operating rules allow for altitude separation of aircraft flying in opposite directions by setting default altitudes. Westbound aircraft fly at even-numbers, while eastbound planes use odd-numbers... which should provide at least 1000 ft of separation. Controllers may direct any altitude... but generally follow default altitude guidelines.

Under those rules, the Embraer should not have been at 37,000 feet because it was flying northwest toward the US. 

"Flights from here (Brasilia) to Manaus should be at even-numbered altitudes, like 36 or 38 thousand feet," Defence Minister Waldir Pires said in a telephone interview with Reuters. "And those from Manaus fly at odd-numbered altitudes."

Authorities are also looking at reports the Legacy's transponder was turned off at the time of the accident -- with the head of Brazil's airports authority, Jose Carlos Pereira, implying the pilots may have done so deliberately.

"We know that the transponder was turned off," said Pereira. "A pilot only turns it off when he doesn't want to be identified. The Legacy could have turned it off to try some air tricks far from the eyes of the air traffic controllers."

But after all-but-indicting the pilots without any concrete evidence, Pereira allowed "it also could have been a case of mechanical failure." (It's important to note that hard evidence in this matter is still hard to come by -- with many reports coming out of Brazil still unverified -- Ed.)

Brazilian authorities insist the pilots are not under arrest, with Judge Tiago de Abril calling it a cautionary measure. She says she wants the two to remain in Brazil until the circumstances surrounding the crash are better understood.

The US consulate in Rio de Janeiro says Lepore and Paladino arrived there Tuesday for medical tests, and questioning by investigators. Consulate officials say they are cooperating fully with authorities.

FMI: www.dac.gov.br/principalIng/index.asp