Space: Little Failure, Large Implications

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August 3, 2020: On July 10, 2020 China’s new KZ (Kuaizhou)-11 solid-fuel satellite launcher failed about a minute after its first commercial launch when the third stage motor failed to ignite. This KZ-11 was carrying two satellites, which were lost. This first launch was supposed to have been in 2018 but there were technical delays. A second KZ-11 launch was already scheduled for late in 2020 and it is not yet known if that will be delayed.

The 78-ton KZ-11 is a larger commercial version of the military LM (Long March) 11. KZ-11 is operated by a commercial launch service company and offers a cheaper (less than $5,000 per pound/$11,000 per kilo to put in orbit) commercial launch service. That’s half the current price and the KZ 11 takes much less time to get ready. That’s because the KZ 11, like the LM 11, uses three solid fuel rocket stages plus a small liquid fuel rocket in the fourth stage to place the payload of about a ton for a 700 kilometer high LEO (Low Earth Orbit) or 700 kg for a SSO (Sun-synchronous orbit) of up to 800 kilometers high. SSO means the orbit keeps the satellite constantly in sunlight, which is optimal for photographic satellites.

China has set up a separate company (Expace) for KZ 11 commercial launches that enable customers to get a satellite into orbit in less than 24 hours. The LM-11 and KZ-11 are both based on the DF-31 ICBM and are launched from a TEL (transporter erector launcher) truck that moved the rocket to the launch site. The main competition of KZ 11 is the Italian Vega, which weighs twice as much and costs about twice as much per pound to put anything into orbit.

While military satellites get more media attention, the real business of space, and where the Chinese put most of their efforts, is in commercial satellites. Because of the increasing popularity of smaller satellites, there are now over a thousand commercial satellites in orbit and this is expected to rise rapidly because of the popularity of mini-satellites (under 100 kg/220 pounds). Some of these mini-sats are much smaller (under ten kg) and still useful. In some cases, dozens of mini-sats are put into orbit by one launcher.

About 75 percent of all satellites are non-military. Most of them are commercial, the rest being government non-military birds. There is a race to develop cheaper, more efficient launchers, like the LM/KZ solid fuel “quick launch” rockets and reusable liquid fuel launchers like SpaceX.

Russia and the United States have both been using retired ICBMs as cheap satellite launchers and that started with older liquid fuel models. China does not have many older liquid fuel ICBMs and has concentrated on developing more reliable and cheaper solid fuel rockets. This is paying off. Moreover, China will sell launch service to just about anyone who can pay, no questions asked.

In April 2018 China demonstrated rapid replacement of satellites in wartime when they used a solid fuel LM 11 rocket to put five imaging satellites into a 500-kilometer-high orbit. Four of these satellites use hyperspectral (can detect a large range of light sources) sensors which can identify 32 spectral bands of light. This type of imager identifies the mineral, vegetation and other aspects of terrain below in great detail and is used for land management and the search for specific minerals and hydrocarbons (oil and gas). These have a resolution up to 10 meters (meaning each ten-meter square area is classified separately according to its spectral characteristics). The fifth satellite captures video of the terrain the hyperspectral imagers cover. The video is higher resolution (90 cm) and captures video in a 22.5-kilometer-wide band while the hyperspectral imagers capture a 150 kilometer wide band. The four hyperspectral imager satellites weighed 80-100 kg each while the video satellite weighed 90 kg (about 200 pounds).

The 58-ton LM 11 was designed for putting military satellites up in a hurry, as in some kind of emergency. But the LM 11 has proved useful in putting multiple smaller satellites into orbit. The five small imaging satellites are part of the Zhuhai 1 constellation of 34 of these small imaging satellites which is mainly serving non-military needs.

An LM 11 can put a single satellite of up to 700 kg (1,540 pounds) into LEO (low earth orbit of under 1,000 kilometers high). LM 11 is considered the smallest member of the Long March family but is very different as it is the only one that does not rely exclusively on liquid fuel rocket engines. The Long March family of rockets has, in general, been very successful with few failures. That means since 1970 liquid fuel Long March rockets had 236 launches and a 95 percent success rate. The LM 11 has had nine launches since September 2015 and all carried multiple satellites (33 in total). One launch was into LEO the others were SSO orbits.