Air passengers expect a meal and maybe an old movie in flight, but travellers on a Vietnamese plane got the surprise of their lives when bikini-clad women posed for a mid-air beauty pageant.

The women in Hawaiian bikinis marched through the cabin on the inaugural VietJetAir (VJA) flight from Ho Chi Minh City to the coastal holiday destination of Nha Trang, the Daily Mail reported.

The women performed a three minute hip-shaking dance, and male passengers reached for their phones to record the scantily-clad beauties, who were all contestants from a local beauty contest, Miss Ngoi Sao.

However, the airline has now been fined by the Vietnam Aviation Authority after a video showing the pageant was posted on YouTube.

A VietjetAir official said it was the first flight to a beach town. "So we came up with the idea of getting a number of girls in bikinis to dance and make passengers happy to improve our customer service."

VietJetAir was the first privately-owned airline to be established in Vietnam. It was granted approval to operate in November 2007. It officially launched in December 2011.