A 40-meter-long tram car is hoisted into an AN-225 cargo plane at Zhengding International Airport in Shijiazhuang on Friday before taking off for Turkey.[Zhang Xiaofeng / for China Daily]

The world's largest cargo plane will carry two green-energy tram cars from Shijiazhuang, Hebei province, to Istanbul, making it the first air transport of high-quality, domestically built equipment of this scale to fly to Europe.

The AN-225, measuring 84 meters long with an 88.74-meter wingspan, arrived at the airport and waited on the parking apron for the loading of the two streetcars, each weighing about 20 metric tons, on Friday.

Compared to commercial planes, which have two engines, the AN-225 has six engines, allowing it to carry heavy loads, and can fly more than 15,000 km in a single flight.

Transporting the streetcars from China to Turkey by air is much more time-efficient compared with traditional means on the sea or by rail, but loading the massive cars was a laborious task.

Twenty-one employees from the AN-225's owner and Ukrainian aircraft manufacturer Antonov installed two giant tracks to guide the 40-meter-long tram cars into the plane and worked from 8 am to about 6 pm on Friday to complete the loading process.

Inside the aircraft, the parallel tracks were fixed to the floor, and various other tethers were attached to keep the streetcars in place during the flight.

The occasion marks the seventh time the enormous cargo plane has landed at Shijiazhuang Zhengding International Airport since 2006. The airport is the only one in the country approved to land the AN-225 by the Civil Aviation Administration of China.

"We (the airport and Antonov) have established a good relationship through the flight," said Qin Guoqiang, manager of international freight at the airport.

"Now we plan to further our cooperation by inviting the plane to stay at our airport when it's not transporting cargo."

Qin said he is confident the plane will be useful for China as international exports — especially those of heavy equipment — continue to boom.

The two tramcars were built in Tangshan, Hebei province, a city known for its manufacturing industry.

The electric-powered streetcars can be used for at least 30 years without discharging emissions, making the cars the first Chinese-built, energy-efficient tramcar to be exported by air to the European market.

"It shows that Hebei is transitioning from light industrial products, such as clothes, to high value-added products," Qin said.

"The closer cooperation between the airport and the cargo company will fuel this type of growth."