Out of 267,548 flights in the first ten months of this year, only 229,393 (85.7 percent) departed on time, down 0.5 percentage points against the same period last year.

The country’s five airlines – Vietnam Airlines, Vietjet Air, Jetstar Pacific, Vietnam Air Services Co. (Vasco) and Bamboo Airways had 7.1 percent more flights year-on-year during the period, the agency reported.

Bamboo Airways, which began flying last January, turned out to be the most punctual airline with an OTP of 93.9 percent. The newly-established airline flew 14,378 flights from January-October.

Vasco, which had fewest flights with 10,661, came in second with an OTP of 93.3 percent, a decrease of 3.4 percentage points from a year ago.

It was followed by national flag carrier Vietnam Airlines which recorded 86,674 punctual flights, equivalent to 88.7 percent, down 0.3 percentage points from a year ago.

Low-cost airline Vietjet Air had an OTP of 82.9 percent, down 0.9 percentage points from a year ago while Jetstar Pacific had the lowest OTP of 80.6 percent.

Aviation authorities blamed overloaded infrastructure and insufficient personnel capacity for flight cancellations and delays. Bad weather conditions have also caused many delays, particularly to and from small local airports.

Last year, Vietnam’s 21 state-run airports served 103.5 million passengers, up 11 percent year-on-year, and the figure is set to rise to 112 million this year, according to the Airports Corporation of Vietnam.

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