The China Airlines co-pilot grounded after August's fatal crash at Chek Lap Kok airport will fly a passenger flight to Hong Kong today. Taiwan's Civil Aeronautics Administration (CAA) gave approval to co-pilot Liu Cheng-hsi to resume flying last month, saying investigations so far had not suggested his performance was a cause of the crash of an MD-11 jet on August 22. The aircraft crashed and overturned in flames while landing during a typhoon, killing three and injuring more than 200 passengers and crew. Mr Liu, 36, who is a trained MD-11 pilot, will fly a 300-seat MD-11 passenger jet with a supervising pilot from Taipei to Kuala Lumpur with a brief stop in Hong Kong. He will take on the first officer's role on the return to Taipei via Hong Kong tomorrow with the supervising pilot. Deputy director of China Airlines' operations division Hou Chun said the flights were a route test to see if Mr Liu needed more retraining before resuming his duties fully as a first officer. Mr Liu, who has undergone some retraining after taking a two-month rest, passed a flight simulator test on Tuesday night. Director of the airline's operations division, Chou Yu-sen, dismissed safety concerns surrounding Mr Liu being assigned to fly the passenger flight as a test. 'It's an international practice. You have to take passengers on board as you cannot fly an empty flight for a route test,' Mr Chou said. 'He's not been disqualified. And he will be accompanied by a check pilot who is the top-ranking pilot in terms of technical operations.' Head of the CAA's flight standards division Hsu Yung-hao said: 'We approved Mr Liu to resume flying after getting an understanding that he was not much implicated in causing the crash.' But Mr Hsu said Mr Liu could still face a penalty such as suspension or licence revocation if the final Hong Kong investigation report suggested he was to blame. Mr Liu, with almost 10 years' flight experience as a pilot, did not comment yesterday. Earlier this month in Taipei he demonstrated to Hong Kong Civil Aviation Department investigators what happened during the accident by using a flight simulator. The pilot of the crash jet, Captain Gerardo Lettich, 58, has been grounded and has returned to Italy. He has had his contract temporarily suspended by the airline pending the investigation in Hong Kong, which may take two years to complete. The airline has raised the possibility of wind shear as a key factor in the crash.