Air Guilin suspended a pilot for life on Monday after he was found to have allowed a female passenger into the cockpit during a commercial flight about 10 months ago.

On Sunday, Sina Weibo user Querenxinhao, who claimed to be an aviation blogger, posted a screenshot of the passenger's post, which shows the woman sitting in the cockpit, without a uniform, with her fingers making a V-sign and cups of drinks on her knees. The woman wrote "Many thanks to the captain. It's so thrilling."

The company, a subsidiary of Hainan Airlines, said that the captain had violated operating procedures and air safety regulations, and that the company would improve safety measures to prevent a similar incident.

"Air Guilin always makes passenger safety a top priority and has zero tolerance for improper or unprofessional behaviors that pose threats to aviation safety," said the statement, which was posted on the airline's account on Weibo.

The airline, based in Guilin, said in a statement on Monday that the unnamed captain let a female passenger into the cockpit during flight GT1011 from Guilin to Yangzhou, Jiangsu province, on Jan 4.

Screenshots of the passenger's other posts indicate she is a flight attendant major at Guilin Tourism University in the Guangxi Zhuang autonomous region.

The captain has been suspended for life, and other staff will be grounded indefinitely for further investigation by the company.

It's not the first case of its kind in recent years. A pilot surnamed Chen with Donghai Airlines allowed his wife to go inside the cockpit on two flights in July last year. The pilot was suspended for six months and his qualifications as a flying instructor with the company were revoked. Two co-pilots and the flight safety officer were also punished.