It is for the third consecutive year that the Vietnamese carrier has been rated so in the website’s annual world’s best airlines rankings. AirlineRatings is the world's only safety and product rater.

The awards, judged by seven editors with over 200 years’ combined industry experience, consider major safety and government audits, with 12 key criteria that include fleet age, passenger reviews, profitability, investment ratings, product offerings, and staff relations.

Since its launch in December 2011, Vietjet has grown its fleet and number of destinations, opening up travel to all including those who perhaps couldn’t afford air travel before, AirlineRatings said.

The carrier, owned by billionaire Nguyen Thi Phuong Thao, has the largest domestic market share of 44 percent.

Earlier this month Vietjet Air was named the "Asia Pacific Low Cost Airline of the Year" at the CAPA Asia Aviation Summit held in Singapore.

It was the first private airline in Vietnam to offer domestic and international services. The budget carrier currently flies on 40 domestic and 66 international routes, operating 385 flights daily within Vietnam and to places such as Japan, Hong Kong, South Korea, Taiwan, Singapore, mainland China, Thailand, Myanmar, and Malaysia.

In AirlineRatings’ other honors, Singapore Airlines won the First Class award and Qatar Airways picked up Best Business Class of the year award.

Last year Vietnam’s 21 state-run airports served 103.5 million passengers, up 11 percent year-on-year, according to the Civil Aviation Authority of Vietnam (CAAV).

The number of visitors travelling by air is estimated to grow at 17.4 percent in the 2016-2021 period, the fastest in Southeast Asia where average growth is estimated at 6 percent, the World Bank said.

Vietnam now has six domestic carriers: Vietnam Airlines, Vietjet, Jetstar Pacific, Vietnam Air Services Company (VASCO), Bamboo Airways, and newly-licensed Vietstar Airlines, a military-run company.

Hospitality group Thien Minh’s KiteAir, tourism firm Vietravel’s Vietravel Airlines and business conglomerate Vingroup’s Vinpearl Air are vying to be the seventh national carrier.