Qantas plane lost contact

AVIATION authorities lost two-way contact with a Qantas plane for more than three hours after it left Sydney airport bound for Johannesburg.The Australian Transport Safety Bureau (ATSB) said today South African authorities tried to contact flight QF63 by all available communication links on May 29, but were unsuccessful."They were trying to talk by a satellite system and a component of that system had failed," aviation safety investigation deputy director, Alan Stray, said."They then tried to communicate with high-frequency radio, but it can be affected by solar activity and down in the deep south it can be more prevalent."It's believed that was happening in the high-frequency radio system, and they couldn't hear the controllers."Mr Stray said flight controllers held no fears the plane had crashed."Alerts do go out when there is a break in two-way communication with aircraft, but as far as I'm aware it didn't get to a search phase," he said."From what I understand, the South African controllers could hear it and there wasn't that level of concern."He said pilots were trained to navigate without communication, and would have continued to follow the last directions issued by the controller."The controller is aware that if they can't issue further instructions, they know the aircraft will continue to follow their instructions," he said.The communication failure was reported to the ATSB.