Flaw in Brazil's System May Be Reliance on High Tech

October 27th, 2006 08:38 AM PDT

BRASILIA, Brazil - On the outskirts of Brazil's modernistic capital city sits a technology-crammed facility that is the backbone of this country's state-of-the-art air traffic control system.

Its network of sensors and communication links, which underwent a $1.4-billion expansion and upgrade last year, is a marvel of ground and airborne radar sensors.

During a Newsday tour of the facility last week, military officers there spoke of the new system with evident pride.

But investigators and aviation inspectors are wondering how it is that despite the planning and technology, the system managed to allow two new planes - one of them flown by a pair of Long Island pilots who have not since been allowed to leave the country - to slam into each other on a calm afternoon at combined speed of some 1,000 miles an hour.

Aviation experts say Brazil's flight control system may be too dependent on high technology, and that better use of old-fashioned radar observation and radio communication might have spared the lives of 154 people.

Brazil's air traffic control system is among the most modern in the world. It monitors Brazil's vast airspace using ground-based and airborne radar antennae, satellite, and microwave communication links to track the position of some 4,500 flights per day.

It is new technology that Air Force Commander Lúio Rivera da Silva is proud of.

An energetic man who began his military career as a pilot himself, Rivera runs the Brasilia air traffic control center, CINDACTA 1, which is responsible for aircraft in about a quarter of the country's airspace.
Striding along a row of air traffic controllers peering into radar screens, he said of the technology, "This allows us to see everything, everywhere."

The midair collision - Brazil's worst-ever aviation disaster - has cast a pall over the room where Rivera stood among working air controllers. None of the more than a dozen controllers on duty during the time approaching the crash have been allowed to return to duty.

Investigators are said to be looking into whether a misunderstanding during a verbal exchange between the Legacy pilots and a controller as they were discussing a proposed change of flight path may have resulted in the Legacy flying at the wrong altitude.

Many of Brazil's air traffic controllers say they are not fully confident of their ability to make themselves understood in English, the standard language for communications between airplane cockpits and air traffic control centers worldwide.

"Here in Brazil we are prepared to speak Portuguese, but in an emergency, they are not able to understand and make conversation that a pilot could understand," said Joaquim Rodrigues, 51, who retired from the Sao Paulo control center in 2002.

Investigators are also looking into whether controller error allowed the two planes to speed at each other.

Controllers work by tracking radar images on video monitors, and telling pilots to either follow their posted flight plan, or to deviate around some hazard, such as dangerous weather or unexpected traffic. Controllers direct pilots to fly at a specific speed, direction and altitude, as a way of keeping them from colliding with other planes.

But critics of Brazil's air traffic control system say though it is technically superb, controllers work under such high stress level - often juggling as many as 15 planes at a time through busy airspace - that remaining focused on all this information can be difficult.