A China Eastern Airlines Corp passenger plane that had started its night-time descent into a Wuhan airport was forced to abort its landing after air traffic controllers had dozed off, an investigation report found.
The incident, which took place on July 8, is the third mishap in two months involving the Chinese carrier.
A transcript of the flight recording released by the Civil Aviation Administration of China on Tuesday shows that the China Eastern flight crew made repeated attempts to contact the duty flight controllers at Wuhan Tianhe Airport - twice in English and once in Chinese. Those calls went unanswered.
The airplane was forced to return to 900 metres and circle the airport for about 10 minutes before landing, the report said. The incident occurred at between 2 to 3 a.m.
China Eastern has suffered other mishaps in recent weeks. On July 17, a China Eastern airplane landed off the runway in the southwest city of Nanning.
Three days later, another China Eastern plane veered off the runway shortly after it touched down at Changzhi airport in Shanxi province amid heavy rain, causing a temporary closure of the airport. No casualties were involved in either incidents.
Chinese airlines have boasted an improved safety record in recent years, following a crash in 2004 that killed 53 people.