Xinhua / Liu Qiaoming by Ganti Images
On Monday, the Long March 4B rocket carried a remote sensing satellite from China’s Taiyuan Satellite Launch Center. The 50-year-old spaceport is located in northwestern China, about 500 kilometers southwest of Beijing.
The first phase of the Chinese rocket, which often begins with the inland Taiyuan facility, cost the spent Long March 4B booster to come down from the spaceport. In this case, it landed near a school, creating a possibly large cloud of toxic gas.
Unlike most spaceports in the world, to avoid such hazards, many launch sites in China are located in inland locations near water. For security purposes, China built its three main launch centers off the water during the Cold War, amid tensions between both the United States and the Soviet Union.
Some impressive footage of the return of the first phase of today’s Long March 4B.
. ps https: //t.co/9oRPoR0ZdF pic.twitter.com/SEl7t1u5xJ
– LaunchStuff (@ LaunchStuff) September 7, 2020
In recent years China has begun experimenting with grid fins to bring its rocket back to Earth and is finally working with its Falcon 9 rocket for a potential land booster like SpaceX. However, the project runs more than a desire to master reuse technology rather than save its population, as China has been starting from Taiyuan since 1968, with perhaps little attention paid to nearby residents.
Given the problem of launching the first phase of the rocket on the surrounding rural area, it is clear that China continues to use toxic hydrazine fuel for its first phase. Hydrogen, which is two nitrogens bound by a hydrogen atom, is an efficient, stable fuel. But it is also very corrosive and toxic.
When the crew Dragon spacecraft exploded during a test in April 2019, it produced large clouds of toxic orange gas that could be seen for miles around the Florida coast. These red clouds were caused by nitrogen tetroxide, an oxidizer that burns with hydrazine fuel. Many people in the past, including these spacecraft – and the space shuttle – used storable table propellants for space operations. NASA is working to find “green” propellants that will prevent the need to use hydrazine even in space operations.
However, for Rocket it is a different story. Hydrazine has been used as a fuel for launch vehicles in most of the world in phases. The last large U.S. rocket to use hydrazine was the United States Alliance’s Delta II rocket, which used toxic fuel in the second phase. The rocket retired in 2018. Russia’s workhorse proton rocket uses hydrazine for its first and second phase.
Yet most of China’s fleet fleet is powered by hydrogen fuel and nitrogen tetroxide id oxidizer. These include its human-rated Long March 2F rocket as well as the widely used Long March 4 family. All these rockets, with their toxic first phase, land on the ground and cause numerous events over the years. This fuel is cheap and relatively easy to use, and it would have been natural for China to use it when these boosters were developed in the 1980s and 1990s. But their use continues today.
China is slowly changing. The new family of its long rockets, the Long March 5 fleet, is fueled by liquid oxygen and kerosene like SpaceX’s Falcon 9 rocket. Paradoxically, however, the Long March 5 rocket usually launches into the sea from the Venchang spacecraft launch site.
