Family: Long March
Long March 12B
Launch statistics
- 1
- Launches (as of July 27, 2026)
- 1
- Successes
- 0
- Failures
- 100.0 %
- Success rate
The Long March 12B (CZ-12B) is a Chinese reusable medium-lift to heavy-lift launch vehicle developed by China Aerospace Science and Technology Corporation Commercial Rocket Co., Ltd. (CACL), a commercial joint venture operating under the state-owned CASC. It has two stages and its first stage is designed to be recovered by propulsive landing; both stages burn kerosene and liquid oxygen. It is the third and most powerful configuration in the Long March 12 family. What separates it from the original CZ-12 and from the CZ-12A is above all its diameter: 4.37 m against the 3.8 m of the other two. Propellant choice also distinguishes it, since the CZ-12A uses methane and liquid oxygen while the CZ-12B is kerolox. It stands about 72 m tall, lifts off at more than 437,000 kg, and its first stage clusters nine YF-102R engines producing 7515 kN; the second stage uses a single YF-102RV of 835 kN. CACL credits it with a "20-ton-class low Earth orbit carrying capacity", roughly 20,000 kg expendable against 12,000 kg when the first stage is recovered, plus about 12,000 kg to a 500 km Sun-synchronous orbit. The 4.37 m diameter was not arbitrary: the design team derived it from the need to fit nine engines in the first stage, from the constraints of transporting stages by road from the factory to the launch site, and from a length-to-diameter ratio of about 16. It flew successfully for the first time on 1 June 2026 from the Jiuquan Satellite Launch Center.
History
Origins within the Long March 12 family
The family began with the CZ-12, a two-stage kerolox launcher from the Shanghai Academy of Spaceflight Technology that first flew on 30 November 2024, debuting both the YF-100K engine and the new Hainan commercial spaceport. In December 2025 came the CZ-12A, the first version with a reusable stage, powered by methane; its initial recovery attempt was unsuccessful although the rocket did reach orbit. The CZ-12B was announced as a more powerful variant of that CZ-12A, developed by CACL with a commercial orientation.
Design and engine selection
The design team explained its choices publicly. Diameter was constrained to between 4.2 and 4.5 metres by the size of the YF-102R engines, by the relative ease of moving stages by road rather than rail, and by considerations of vibrational mode and structural response under launch loads; with a length-to-diameter ratio of about 16 and an overall length near 72 metres, 4.37 metres was ultimately selected from a "preferred number system". According to Shan Lei of CASC, the YF-102R and YF-102RV engines were chosen for their open-cycle design, simpler and more robust than staged combustion, which speeds development at the cost of some efficiency; they allow multiple restarts and a wide range of thrust adjustment, both prerequisites for stage recovery and reuse. Their post-pump oscillation mechanism, in which only the thrust chamber section swings, occupies little lateral space and eases the tight nine-engine layout.
Testing and first flight
On 16 January 2026 a static fire test of the first stage took place at the Dongfeng Commercial Space Innovation Test Zone within the Jiuquan Satellite Launch Center. The first launch, flight Y1, lifted off on 1 June 2026 at 08:40 UTC from the CZ-12 pad at Jiuquan and successfully placed Qianfan Polar Group 08 into orbit. First-stage recovery was not attempted.
Launch timeline
| Date | Launch site | Outcome | Payload |
|---|---|---|---|
| Jun 1, 2026, 8:40 AM | Long March 12 series Pad | Success | First test launch of CASC/CACL’s Long March 12B rocket; carried a batch of 2 operational Low Earth Orbit communication satellites with Ku, Q and V band payloads for the G60 constellation operated by Shanghai Spacesail Technologies with funding backed by the Shanghai local government. Initial constellation will consist of 1296 satellites by 2027 with long term plans to expand it to 12000 satellites. |