In Thailand, there is a commercial airport operating inside an active military base. It is known as U-Tapao Rayong Pattaya International Airport (UTP). The airport is located in Ban Chang District, Rayong Province.
Although originally built for military operations, the airport gradually developed into a commercial gateway supporting the eastern region of Thailand.
Legacy of a Post-Vietnam War Military Airbase
U-Tapao Rayong Pattaya International Airport initially served as a small-scale military airfield constructed by the Thai government in 1961.
The facility was expanded in 1965 after Thailand granted permission for the U.S. military to use the airbase in support of the Vietnam War.
The United States redesigned the runway into a 3,505-meter concrete structure capable of handling heavy B-52 Stratofortress bombers and KC-135 tankers.
In July 1966, the airbase became fully operational, and served as a primary hub for B-52 missions in Indochina. Following the end of the Vietnam War in 1976, U.S. forces vacated the site, and handed total control over to the Royal Thai Navy as a naval aviation base.
By 1989, the Thai government began allowing private airlines to operate commercial routes from U-Tapao to Koh Samui. However, commercial flights remained limited, which left the airport primarily as a military base for the next two decades.
Temporarily Replacing Bangkok's Main Airports in Late 2008
After opening limited commercial flights in 1989, general aviation activity at U-Tapao Rayong Pattaya International Airport showed little immediate growth. The airbase continued to function mainly under the Royal Thai Navy.
In late 2008, U-Tapao's role shifted dramatically when massive protests shut down Bangkok's two primary airports, Suvarnabhumi and Don Mueang. The closures left approximately 100,000 foreign tourists stranded as all flights to and from the capital ground to a halt.
In response to the emergency, the Thai government redirected international flights to U-Tapao. Located about 140 kilometers from Suvarnabhumi Airport, the military base served as a temporary alternative airport to repatriate stranded foreign tourists.
Further Development of U-Tapao Airport
The Thai government subsequently recognized U-Tapao's potential to relieve pressure on Bangkok's two main airports.
In June 2015, the Ministry of Transport and the Royal Thai Navy signed an agreement to develop the airport. The initiative focused on upgrading existing facilities, including renovating the older terminal and widening access roads toward Bangkok.
Alongside the renovations, the agreement intended to build Terminal 2 as a new passenger facility. Opening in February 2019, the new terminal expanded the airport capacity from 800,000 to 3 million passengers per year.
In 2017, the Thai government integrated U-Tapao into the Eastern Economic Corridor (EEC) special economic zone. The airport’s surrounding area was designated as an aviation hub named Eastern Aviation City. The area is planned to integrate logistics centers, commercial districts, and aircraft maintenance facilities
The government signed a joint venture contract with the UTA consortium (U-Tapao International Aviation) on June 19, 2020. The project covers 1,154 hectares with a total investment of 217.9 billion Baht (approximately US$7 billion) under a 50-year concession.
Regulatory approvals and technical preparations progressed in stages. Environmental impact assessments and connecting highway designs were finalized in 2022, followed by air navigation system approvals and the second runway tender in 2023.
The government officially handed over the land to the consortium in 2024. Following loan agreements in 2025, physical construction of the second runway and Eastern Aviation City officially began on April 3, 2026.
