Investigators are still no closer to discovering the cause of last week's Crossair crash near Zurich in which 10 people died. The black box flight recorders have given no indication as to the direct cause of the accident.

Investigators are still no closer to discovering the cause of last week's Crossair crash near Zurich in which 10 people died.

They said the data on black box flight recorders was in good condition and usable, but had not allowed them to determine the direct cause of the accident, nor to exclude anything.

The head of the Federal air accident investigation bureau, Jean Overney, said he was expecting a long and difficult inquiry, which could last as long as a year.

A Swiss investigator returned from Canada on Friday with the cockpit and flight data recordings. The black boxes had been taken to a laboratory in Canada to be studied.

Overney said the cockpit voice recorders showed the crew acting very calmly and in a professional manner. Nothing in their conversations indicated a technical problem. He refused to say whether the pilot or co-pilot was at the controls when the plane crashed.

The flight data recorder showed that all 64 parameters measured - such as speed and altitude - were normal shortly before impact.

It was hoped that the black boxes would mbe able to shed light on why the plane - a Saab-340 owned by the Swiss regional airline, Crossair - veered to the right instead of banking to the left, as planes normally do when taking off from Zurich Kloten airport. The Dresden-bound plane crashed near the village of Niederhasli, just two minutes after take-off on January 10th.

All seven passengers and three crew members on board died.

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