Long March 11, LM-11, Chang Zheng 11, CZ-11, Shiyan 21, SY-21

Shiyan 19 | Long March 11

Liftoff Time
March 15, 2023 — 11:41 UTC | 19:41 BJT
Mission Name
Shiyan 19, an experimental satellite
Launch Provider
(What rocket company launched it?)
China Aerospace Science and Technology Corporation (CASC)
(Who paid for this?)
Probably the Chinese government, given the nature of the payloads
Long March 11 Y11
Launch Location
Site 95A, Jiuquan Satellite Launch Center, China
Payload mass
Where did the spacecraft go?
A circular Sun-synchronous orbit (SSO), at ~505 km (~314 mi) and 97.46 degrees inclination
Did they attempt to recover the first stage?
No, stage recovery is not a capability of the Long March 11
Where did the first stage land?
The first stage crashed into inland China
Did they attempt to recover the fairings?
No, fairing recovery is not a capability of the Long March 11
Were these fairings new?
This was the:
– 37th orbital launch attempt of 2023
– 10th Chinese launch of 2023
– 9th launch provided by CASC of 2023
– 1st launch of a Long March 11 of 2023
– 16th successful launch of a Long March 11
– 16th launch of a Long March 11
– 467th mission of a rocket from the Long March family
Where to watch
Unofficial launch summary

How Did It Go?

The China Aerospace Science and Technology Corporation (CASC) successfully launched the Long March 11 Y11 vehicle, which carried the Shiyan 19 (SY-19) experimental satellite into a 505 km (~314 mi) circular Sun-synchronous orbit at 97.46 degrees inclination. Liftoff took place from Site 95A, at the Jiuquan Satellite Launch Center, in Inner Mongolia, China.

Shiyan 19, SY-19, Long March 11, CZ-11, patch
Mission patch (credit: CASC)

What Is Shiyan 19?

Shiyan Satellites

China’s aerospace industry has a number of prolific programs aimed at improving applied technologies in this field. The Shiyan 19 satellite is indeed part of a series of spacecraft of the same general designation. These certainly play a role in the mentioned search for progress. Particularly, this fact is highlighted by the Chinese word used for their name — Shiyan, or SY for short — which, some experts point out, should be translated as “pilot” or “trial.” However, these satellites are more commonly mentioned as “experiment,” a more widely used translation.

Other series aiming to achieve similar goals are the Shijian, or SJ — best practice, put into practice — and the Chuangxin, or CX — innovation. Both SJ and SY payloads have been contributing for decades now to the China High-resolution Earth Observation System (CHEOS). Apparently, though, a distinction can be made between those last two, as the Shijian sats have favored more radar and infrared payloads. On the other hand, Shiyan have been more focused on Earth-observation satellites.

In order to further differentiate the SY from the SJ, the latter are probably testing, or putting into practice, more mature technologies. These could imply a lower failure ratio, when compared to the Shiyan more experimental spacecraft. Similarly, the Chuangxin might also find themselves in an early condition.

Shiyan 19

Not much has been disclosed about this payload, so we have to rely on the explanations in the previous paragraphs. However, Chinese authorities have reported that the Shanghai Academy of Spaceflight Technology (SAST) developed the SY-19. Apparently, this includes both its platform and whatever payload it carries. Official sources stated this satellite would perform the following tasks: “land resource surveys, urban planning, disaster prevention and mitigation, and other missions.”

Other Shiyan Launches

As previously mentioned, these satellites are part of a larger group of “pilot” payloads. In the following table you can find some other Shiyan spacecraft that were launched in the past.

DateLaunch VehicleMission Name
November 24, 2021 – 23:41 UTCKuaizhou-1AShiyan 11
December 23, 2021 – 10:12 UTCLong March 7AShiyan 12-01 & 02
January 17, 2022 – 02:35 UTCLong March 2DShiyan 13
September 24, 2022 – 22:55 UTCKuaizhou-1AShiyan 14 & 15
September 26, 2022 – 23:50 UTCLong March 6Shiyan 16A/B & 17
October 29, 2022 – 1:01 UTCLong March 2DShiyan 20C
December 12, 2022 – 08:22 UTCLong March 4CShiyan 20A & 20B
December 16, 2022 – 6:17 UTCLong March 11Shiyan 21
December 29, 2022 – 4:43 UTCLong March 3/B/EShiyan 10-02
January 13, 2023 — 7:00 UTCLong March 2DYaogan 37 & Shiyan 22A/B
List of the latest 10 Shiyan launches

What Is The Long March 11?

Developed and manufactured by the China Academy of Launch Vehicle Technology (CALT), one of CASC’s subsidiaries, the Long March 11 — also known as Chang Zheng 11, or CZ-11 — is a small satellite launch vehicle. Its maiden flight happened on September 25, 2015.


Because of its design and its specifications, this Chang Zheng is incredibly versatile, being capable of both launching on short notice, or from either land or sea. In the former case, the focus is on keeping short operational timelines, while in the latter, on mission’s cost. During normal operations, the launch can take place within ten days from receiving the order. In emergencies, this time can be drastically reduced to about 24 hours.


When launching from the sea, the rocket is identified as CZ-11H, where H probably stands for haiyang: ocean. Because of this, their flights are numbered separately, though the vehicle serial numbers are not. In this way, it becomes clear that they are identical from a manufacturing standpoint.

PropellantSolid (all stages)
Lift-off mass [kg (lb)]58,000 (~128,000)
Lift-off thrust [kN (lbf)]1,177 (~264,500)
Height [m (ft)]20.8 (~68)
Diameter [m (ft)]1.6 (~5.2)
2.0 (~6.5) (1st stage)
Fairing diameter [m (ft)]1.6 (~5.2), or
2.0 (~6.5)
Mass to LEO [kg (lb)]700 (~1,550)
Mass to SSO* [kg (lb)],
at 700 km (~438 mi) altitude
400 (~770)
Long March 11’s specifications
(*) SSO: Sun-synchronous orbit

Furthermore, a mobile launcher, basically a truck with an erectable strongback, provides the launch platform when it is from land. On the other hand, if it lifts off from the sea, the rocket uses different barges, namely the Tai Rui, the DeBo-3, and the DeFu-15002. However, in both cases — land and sea — the rocket’s first stage ignites in the air. This is due to the Long March 11 leaving the ground similarly to a missile, that is, carrying out a cold launch. When such a system is used, the rocket is propelled by gas from a launch tube. Only then it starts generating its own thrust.

Long March 11, De Bo 3 launch platform
A Long March 11 rocket launches from the De Bo 3 in 2020 (Credit: Xinhua)

Chang Zheng 11 Yao 11

Eleven is the number that presently identifies the flight (Y11) of the CZ-11. So far, it successfully carried out twelve missions from the ground, and another four from the sea. On a different note, the rocket used the fairing with a 2.0 m (~6.5 ft) diameter, while its other option is the one with a 1.6 m (~5.2 ft) diameter.

Previous CZ-11 And CZ-11H Launches

DateVehicle VariantMission NameFlight IDLaunch Site
September 15, 2020 – 1:23 UTCCZ-11HJilin-1 Gaofen 03B-01 to 06 & 03D-01 to 03Y2DeBo-3,
Yellow Sea
December 09, 2020 – 20:14 UTCCZ-11GECAMY9Mobile launcher,
Xichang SLC*
March 30, 2022 – 02:29 UTCCZ-11Tianping-2 A/B/CY10Mobile launcher,
Jiuquan SLC*
April 30, 2022 – 03:30 UTCCZ-11HJilin-1 Gaofen 03D-04 to 07 & 04AY3Tai Rui,
Yellow Sea
October 7, 2022 – 13:10 UTCCZ-11HCentiSpace-1 S5 & S6Y4DeFu-15002,
Yellow Sea
December 16, 2022 – 6:17 UTCCZ-11Shiyan 21Y12Mobile launcher,
Xichang SLC*
(*) SLC: Satellite Launch Center

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