The CAAV asked the Ministry of Construction to approve the revised timeline for the projects, which fall under Component 4 of the airport's first phase in Dong Nai City.
Under contracts amended in June, contractors were required to finish construction on the six projects by Aug. 31.
But only two have reached the equipment installation stage: the No. 2 aviation catering facility and the No. 2 ground handling and vehicle maintenance center.
The remaining four projects have yet to complete basic construction. These include the No. 1 catering facility, the No. 1 ground handling center, and aircraft maintenance facilities No. 1, 3, and 4.
The CAAV attributed the delays to massive workloads, labor and material shortages, and fluctuating fuel prices. Extended shipping timelines for specialized imported equipment further disrupted the schedule.
Unfinished common technical infrastructure at the airport has also hindered contractors from organizing work sites, building access roads, and connecting to utility networks, it said.
The aviation authority emphasized that Dec. 24 is the final deadline for completing construction and equipment installation. It stated there is no basis for further extensions before the airport officially begins operations at midnight.
Spanning approximately 5,000 hectares, the VND336.63 trillion (US$13.16 billion) Long Thanh Airport is designed to ease the burden on Ho Chi Minh City's Tan Son Nhat Airport, which is 40 km to its west.
The mega-project's first phase features a single runway and passenger terminal with an annual capacity of 25 million passengers and 1.2 million tons of cargo.