Nanjing, capital of eastern China’s Jiangsu Province, used a drone to assist with construction of a suspension bridge across the Yangtze River yesterday, the first drone-assisted engineering feat of this kind in the province, Chinese media reported today.
A vector hexacopter, or six-rotor drone, carried the cable, 2.3km long and 2.5 mm across, and flew across sections of China’s longest river near Nanjing and two neighboring cities Zhenjiang and Yangzhou.
The drone took off around 9:42am from the top of the southern tower of the bridge and landed on the top of the northern tower eight minutes later.
The bridge, with a planned length of 5 km and a six-lane two-way expressway, allows for a maximum car speed of 100 kph. The span of the main bridge is 1.56 km.
The pilot cable’s arrival on the other end of the bridge paves the way for installing steel cables and constructing the upper part of the bridge, media said.
According to the company in charge of engineering work, the bridge stands above a busy section of Yangtze River.
Conventional methods of transporting the pilot rope, such as using a vessel to haul the cable across the river, require closing the waterways for four to five hours.
“This could impede shipping activities,” said Jiang Nengshi, an executive deputy manager overseeing the building project.
He added builders decided upon a drone-powered operation since it is safe, efficient, precise and causes minimal disturbance to shipping traffic.
The engineers also deployed a “flymate” copter to film and monitor the drone’s flight across the river.
China is not new to using drones in bridge cable installation. In 2017, for instance, workers building the 4,629-foot-long Xingkang Bridge in southwestern Sichuan Province used a drone to help install cables and construct overpasses faster.