Chinese tourists have suffered yet another blow to their image in the wake of an in-flight brawl that made international headlines. The Thai AirAsia jet headed for Nanjing was forced to return to Bangkok earlier this month after a few unruly passengers got angry with the seating arrangements and service and threatened to blow up the plane. A flight attendant was reportedly scalded by hot water and instant noodles. The mid-air drama is an individual case. But it adds to a long list of jaw-dropping behaviour that has seriously undermined the image of mainland tourists. The group of four was rightly punished when they returned home. They were blacklisted from travelling by the provincial tourism board. The tour guide also had had his licence suspended for a year. It is good that their misbehaviour has been taken seriously by the authorities. The sanctions should send the right message that tourists acting out of line will not be condoned. The outcome would have been different had the tourists followed the normal channel to file a complaint against the services they deemed unsatisfactory. But some mainlanders believe they need to be loud and pushy to get what they want. This is not the first time tourists' bad manners have caught the state's attention. Last year, the national tourism administration issued guidelines on "civilised travelling". In a rare appeal during a visit to the Maldives in September, President Xi Jinping urged Chinese tourists to try local seafood rather than eating home-bought instant noodles in their hotel rooms. The government needs to better educate tourists on travelling etiquette. More than 100 million mainlanders travelled abroad this year. Those with ill manners are in the minority, but they are the ones who tend to leave lasting impressions. The latest incident is a reminder that misbehaviour may well affect perception, and hence the overall image of Chinese tourists abroad.