A former head of the French Concorde programme has been placed under formal investigation over the Concorde crash of July 2000 in which 113 people died.
The Air France Concorde flight crashed shortly after take-off
Henri Perrier, who worked for the firm Aerospatiale, is being investigated for involuntarily causing death and injury.
Mr Perrier is accused of having been told about faults in the aircraft but having done nothing to put them right.
The Air France Concorde caught fire and crashed soon after take-off from Paris' Charles de Gaulle airport.
Mr Perrier had worked on the Concorde programme since the plane's launch in the 1960s.
Chief engineer at the time of the supersonic plane's first test flight in 1969, he directed the Concorde programme in the 1980s and early 90s.
He was placed under formal investigation - one step short of formal charges - after being questioned for 11 hours on Monday by an investigating judge in Paris.
Mr Perrier made no comment when he emerged from questioning with his lawyers, the AFP news agency reports.
Speaking in 2001, he said "nothing we knew would ever have led us to believe that such a catastrophe could happen."
Henri Perrier, second right, worked on the first test flight in 1969
"This was a catastrophic mishap," he told the Associated Press in an interview.
A lawyer representing some of the victims has welcomed the investigation.
Three other former Aerospatiale executives are also to be called before the judge.
Aerospatiale is now part of EADS (European Aeronautic Defence and Space Company), the majority owner of Airbus. A spokeswoman for Airbus said the company had no comment to make on the case involving the retired Aerospatiale executives.
Earlier this year Continental Airlines and one of its mechanics were also placed under formal investigation.
Inquiries had revealed that debris from a Continental DC-10 on the runway had caused the Concorde's tyre to burst.
Fragments from the tyre then punctured the plane's fuel tanks, causing the fire.