(Yicai Global) July 18 -- China's aviation regulator has punished the national flag carrier for its latest blunder which involved one of the co-pilots smoking an electric cigarette in the cockpit.

The Civil Aviation Administration of China reduced Air China's Boeing 737 flights that depart from Beijing by 10 percent, or 5,400 hours a month, local tabloid Nanfang Metropolis Daily reported. The CAAC handed a fine of CNY50,000 (USD7,500) and ordered the airline to rectify all safety issues within 3 months. The punishment also included suspensions or recalls of the involved staff members' commercial licenses.

On July 10, Air China's 737-5851 aircraft was on its way from Hong Kong to northern China's city of Dalian when a co-pilot tried to turn off a fan to smoke an e-cigarette but instead closed the air-conditioning, which triggered an altitude alert in the cabin. After the plane had plunged to 3,000 meters of height, or one-third of the usual flying altitude, the staff realized what was wrong and opened the AC again to resume normal operations.

Air China suspended flight qualifications of the involved crew and terminated their employment contracts in accordance with the law, the firm said on its microblogging Sina Weibo account on July 13.

The airline's stock price fell to HKD7.03 (USD0.9) at 2.50 p.m. Beijing time from yesterday's closing price of HKD7.13.

Editor: Emmi Laine