That’s a good explanation, and I don’t doubt the growth potential of CZ-9. However connecting the dots like this is wishful thinking and CZ-9 has never been described to be so big, nor has a YF-215 upgrade variant been shown. I have big problems with the original graphics from the Chinese posters because it’s a completely non-fictional representation of the CZ-9, while being labeled as “CZ-9”
It has now the internet thinking CZ-9 will be a monster rocket that dwarfs starship V4 which is absurd.
Translation:
1. Firstly, regarding the concept images made by online enthusiasts, you actually don’t need to look at them. That 185-meter Long March 9 rocket concept image is absolutely nonsense. According to the data in that image, the total mass of liquid oxygen-methane fuel for just the first and second stages of the rocket is between 7,200 and 8,000 tons. Adding the third stage, the overall rocket mass, and payload mass, the liftoff mass would exceed 9,000 tons, requiring 13,000 tons of thrust for the rocket to even take off. This isn’t just ordinary nonsense—it’s ignorant-level nonsense. Anyone with even a basic understanding of rocket data wouldn’t come up with this. Including conceptual heavy-lift rockets like Sea Dragon and NOVA in the same table already calls their professionalism into question. Look at actual aerospace experts—who references Sea Dragon and early NOVA configurations? Those configurations not only never existed in reality but were doomed from the start. This isn’t the 1960s, when human understanding of space was superficial. Back then, tools were scarce and knowledge was shallow, so some unrealistic designs emerged. No one pursues that now.
2. However, I hope everyone understands that all the designs of CZ-9 you’re seeing now are only for the first phase of CZ-9. This model will definitely undergo major revisions, and the improvements will be astonishing. Actually, as far as I’m concerned, China’s aerospace literature and official documents have been saying this for 10 years, and not just in one document. It also includes explanations from subsystem chief designers in interviews with Xinhua News Agency.
Currently, CZ-9’s thrust is in the 6,000-ton class, but in the older version of CZ-9’s plan from 5 years ago, there were designs exceeding 6,000 tons of thrust (2–4 solid boosters of 1,600 tons each + core stage thrust of 2,000 tons = 8,400 tons). You can check my earlier posts on this site—I remember posting an image, originally from a large-scale solid launch vehicle roadmap exhibition board around 2022–2023 (no one noticed, but I saw it).
Let me briefly explain: The earliest preliminary research for the Long March 9 rocket was conducted from 2005 to 2010 (during a Five-Year Plan). This was the early exploration phase, with the rocket targeting LEO payloads of 100 tons, largely referencing the Energia rocket, the U.S. Space Shuttle, and Saturn V. At that time, CZ-9 had not yet been assigned a specific model designation. It was simply referred to as a heavy-lift launch vehicle. Just like CZ-10, which, before 2020, was mostly referred to in professional literature as the “new-generation crewed launch vehicle.” Most Chinese space fans confused that name with the crewed versions of CZ-7 and CZ-5.
After 2011, the CZ-9 rocket designation was formally established, and it was internally confirmed from the start as a rocket requiring a 20-year development cycle (as explicitly mentioned in literature by an academician in the aerospace system). In other words, in 2011, when the CZ-9 designation was confirmed, it was already decided that CZ-9 would enter service after 2030. Internally, the development cycle for a Chinese rocket is 10 years (two Five-Year Plans: one for component development and one for integration, not counting preliminary research time). Because heavy-lift rockets have a relatively high starting point, when the rocket model was confirmed in 2011, considering the lessons from U.S. and Soviet heavy-lift rocket development, it was decided that the first 10 years would focus on supplementary research and in-depth key technology studies, fully mastering and breaking through the foundational technologies for heavy-lift rockets. The following 10 years would be for building the rocket. Simply put, China’s new large rockets have always followed a schedule of 5 years of preliminary research + 5 years of components + 5 years of integration. For heavy-lift launch vehicles, it was decided from the start: 5 years of conceptual preliminary research + 5 years of specific configuration selection + 5 years of key technology deepening research + 5 years of component development + 5 years of integration.
As early as 2010, it was already decided to plan for crewed lunar landing around 2024–2025 (later officially paused in 2013 and resumed in 2018). The rocket for this plan was the kerosene first-stage version of CZ-5 (CZ-5DY), now the CZ-10 series rockets.
From 2010 to 2015, CZ-9 (configuration selection phase, strap-on two-and-a-half-stage design) started with the Energia rocket and Ares V as templates. It had no high-orbit capability (two-stage launch vehicle), and due to clear lunar mission requirements, LEO payload capacity referenced Saturn V, set at 120–130 tons. At that time, CZ-9’s liftoff mass was around 3,000 tons, with liftoff thrust around 4,000 tons.
From 2015 to 2020, CZ-9 (key technology deepening research phase, strap-on three-and-a-half-stage design) had a liftoff thrust just under 6,000 tons and a liftoff mass just over 4,000 tons (around 4,1xx tons). In this phase, the three-and-a-half-stage design was confirmed, essentially a smaller-core Saturn V with strap-on boosters. Actually, this strap-on Saturn V was also a NASA plan at one time.
By 2020, it was almost time to enter the actual rocket development process. According to related literature, by 2019–2020, relevant institutions had already mobilized hundreds of personnel, made extensive preparations for coordinating with supporting factories, and initiated trial production of components (with thousands of specification documents). Vast amounts of procedural documents were compiled, just waiting for the green light.
Later, as everyone saw, with the appearance of Starship, the issue of reusability for heavy-lift rockets emerged. The top level of China’s aerospace sector pressed the pause button to reassess CZ-9’s reusability design. During the early configuration selection and key technology deepening research phases, China studied hundreds of configuration options (evidenced in literature), but one option was notably missing: the single-stick (no strap-ons) configuration. Most of China’s selected configurations were strap-on designs. The single-stick configuration is more conducive to rocket reusability (the old CZ-9 had reusability plans, but recovering five first-stage bodies simultaneously was too troublesome. Also, strap-on reinforcement for heavy-lift vehicles is extremely challenging, and China was using liquid boosters, where fluid dynamics simulations for liquid sloshing in tanks are incredibly complex and painful. Moreover, the earlier CZ-9 design prioritized strap-ons for maximum payload, so the core single-stick performance and structural mass degradation, combined with reusability losses, made it meaningless). Therefore, from 2021 to 2025, China readjusted the design for a reusable single-stick CZ-9.
