Emergency personnel conduct search operations in the water near the site of the crashed TransAsia Airways plane in Taipei on Friday. The pilot of the doomed plane was hailed as a hero for his actions in the final moments before the crash. [Photo/AP]

The exact cause of the crash remains unclear but initial analysis of the flight data recorder and the cockpit voice recorder by the Aviation Safety Council showed the right engine of the plane flashed a warning signal just 37 seconds after takeoff and pilots manually cut the fuel supply to the left engine, leading to a loss of power in both engines before the plane went down.

Thomas Wang, managing director of the ASC, said the pilot announced a "flame-out", which can occur when the fuel supply to the engine is interrupted or when there is faulty combustion. However, Wang said there was in fact no flame-out, and the engine on the right side had shifted into idle mode without any change in oil pressure.

The 72-seater aircraft, an ATR 72-600 manufactured by Franco-Italian firm ATR, is able to fly or take off with just one functioning engine, said Yann Torres, of France's aviation accident investigation bureau (BEA) who has joined the investigation.

Wednesday's accident was the second fatal crash for TransAsia after a July disaster that left 48 people dead.

"We have imposed a one-year ban on TransAsia from applying for new routes as a penalty," said Civil Aeronautics Administration director Lin Tyh-ming.

Taiwan media said the authorities were looking into allegations against the airline, including labor shortages and insufficient training, which could have affected safety standards.