The rocket's development was delayed by technical challenges but all of the issues were resolved for the upcoming launch in which the weight load will be a hefty 800 metric tonnes.
China's largest launch vehicle, the 2.5 stage Long March 5, that debuted last November, is preparing for another launch with a window of July 2 to July 5 of the Shijian-18 experimental telecommunications satellite to geostationary transfer orbit. The huge Shijian-18 is based on China's new, untested Dongfanghong-5 (DFH-5) satellite platform weighing in at seven metric tonnes it is one of the largest satellites that will be in geostationary orbit. This will be the rocket's second launch from the Wenchang Satellite Launch Center on Hainan Island, and is expected to be streamed live.
The High-Throughput satellite's capacity will be approximately 70 Gbps, and will test both space-based laser communications and powerful LIPS-300 ion thrusters, which will be used for station keeping. The Long March 5 compared to other powerful active rockets such as the Delta-IV Heavy, Atlas V and Ariane 5, was developed by the China Academy of Launch Vehicle Technology (CALT).
Long March 5 will also launch China's first independent interplanetary mission to Mars in 2020. A variant for low Earth orbit launches, the Long March 5B, will be used to launch 20 metric tonne modules for the future Chinese Space Station.
The rocket's development was delayed by technical challenges but all of the issues were resolved for the upcoming launch in which the weight load will be a hefty 800 metric tonnes. The rocket is fueled by crogenic liquid hydrogen, kerosene and liquid oxygen. The Long March 5 family can launch a payload of 25 tonnes to low Earth orbit, 14 tonnes in geostationary transfer orbit, thereby boosting China's launch capabilities by 2.5 times over pre-existing Long March carrier rockets.
The new launch vehicle required new facilities because, unlike the Long March 2, 3, and 4 that were easily transported by train to the three inland launch sites at Jiuquan and Taiyuan in the north and Xichang in the southwest, the five-meter diameter core of the Long March 5 makes it too wide for the transport infrastructure. The new coastal launch center was required and it took two ships to deliver the rocket to the southern island province of Hainan. Being closer to the equator, the Wenchang launch site also gives rockets a boost from the greater rotational speed of the Earth.