Three airline disasters involving Malaysian-affiliated carriers in less than a year have dented confidence in the country's aviation industry and spooked travellers across the region.

In the third incident, Malaysia Airlines Flight MH17 was shot down over Ukraine on July 17, killing all 298 people on board.

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On board Flight QZ8501 were 155 Indonesians, three South Koreans, and one person each from Singapore, Malaysia and Britain. The co-pilot was French.

US law enforcement and security officials said passenger and crew lists were being examined but nothing significant had turned up and the incident was regarded as an unexplained accident.

The plane, which did not issue a distress signal, disappeared after its pilot failed to get permission to fly higher because of heavy air traffic, officials said.

Pilots and aviation experts said thunderstorms, and requests to gain altitude to avoid them, were not unusual in that area.

The Indonesian pilot was experienced and the plane last underwent maintenance in mid-November, the airline said.

Indonesia AirAsia is 49 percent owned by Malaysia-based budget carrier AirAsia.

The AirAsia group, including affiliates in Thailand, the Philippines and India, had not suffered a crash since its Malaysian budget operations began in 2002.

The plane's disappearance comes at a sensitive time for Jakarta's aviation authorities, as they strive to improve the country's safety reputation to match its status as one of the airline industry's fastest growing markets.