Chinese Hypersonic Developments (HGVs/HCMs)

Post #309 is about wind tunnel test of the whole system by CASC.
Post #310 is about engine development by CASIC.
Besides the two entities from rocketry, there are also numerous entities from Aero industry/research.

Apparently, the program is a national combined effort that every entity is part of it. This is once again the reason that I keep on reminding people when observing China, there is practically no rivalry between companies (CAC vs. SAC) like in the US. If there is or any such attempt by individuals, it is the individual to be removed or company being reshuffled, dismantled or reassembled at the will of state.

Another evidence that 2025 is the miles stone of all types competing engine designs to be ready. One can also see that both engines have the same milestones of thrust and speed level improvement, phase 1 2025, and phase 2 2030.

This is the extraction from the paper of TRRE engine.

taxiya said:

Post #309 is about wind tunnel test of the whole system by CASC.
Post #310 is about engine development by CASIC.
Besides the two entities from rocketry, there are also numerous entities from Aero industry/research.

Apparently, the program is a national combined effort that every entity is part of it. This is once again the reason that I keep on reminding people when observing China, there is practically no rivalry between companies (CAC vs. SAC) like in the US. If there is or any such attempt by individuals, it is the individual to be removed or company being reshuffled, dismantled or reassembled at the will of state.

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I’ve concluded that one of the problems with the competition is good for innovation argument is that it mistakes positive effects competition has for design as positive effects for engineering and science. Design innovation benefits from competitive dynamics. Engineering and science innovation suffers from competitive dynamics. The former requires selection pressure, which is what competition brings. The latter requires knowledge pooling and information sharing, things which competitive incentives actually harm more than help.

taxiya said:

Another evidence that 2025 is the miles stone of all types competing engine designs to be ready. One can also see that both engines have the same milestones of thrust and speed level improvement, phase 1 2025, and phase 2 2030.

This is the extraction from the paper of TRRE engine.

View attachment 55699

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Looks like the speed improvement milestone in Phase 2 2030 is depending on the availability of the high-speed turbine engine.

WS-15 will be ready by then

ILikeChina said:

WS-15 will be ready by then

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Does the "Ma=4 Engine" mean Mach 4 engine? WS-15 can't be used as at such high speed It has to be a turbojet engine.

ILikeChina said:

WS-15 will be ready by then

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It is not WS-15 but share tech base developed through WS-15, probably the core which is a turbojet. Turbo Fan like WS-15 can never reach Ma=4.

Quickie said:

Looks like the speed improvement milestone in Phase 2 2030 is depending on the availability of the high-speed turbine engine.

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Regarding this one (Ma 4 turbine), it is a preferable option, but it is not a must-have.

A TBCC which is what US is working on, starts at 0 to Ma 2 or slightly Ma 3 on turbine power.This is an ordinary turbojet. RAM jet (mode) however need the speed above 3 or 4 to work, SCRAM need something around 5 or 6. So there is the thing called "thrust gap" between the turbine mode and RAM mode transition. That is what NASA is struggling right now and NASA is hoping on two breakthroughs in the future: 1. to increase turbine engine to work up to Ma 4. 2. to reduce Scram to M3.


China's approach is rather ingenious like J-20's side weapon bay's launching mechanism. It is TRRE, it is a TBCC+RBCC, adding induction rocket in the RAM/SCRAM combustion channel to cover the thrust gap. The rocket itself generate thrust but relatively small, the main purpose is the little thrust will suck in much more air into the inlet to burn the fuel.

However, China does not drop the hope of a pure TBCC approach like NASA, IF a Ma-4 engine is realized. This approach is simpler than TRRE and less mode transition control. But that is not a requirement.

IMO, availability of Ma-4 engine won't stop or delay the "two stage in orbit space craft" program.

Just one more thought, the "pre-cooler" engine may serve as one option of the Ma=4 turbo engine. By today's knowledge, such engine can work up to Ma=5.

However, SABRE in its current form is certainly not usable in a TBCC setup because SABRE has its RAM air path surrounding the turbine, while in TBCC, the turbine air flow is parallel to the RAM/SCRAM air way. With the turbine block stay in the middle of RAM air way, the engine can never go to SCRAM (Ma>5 to 10).

I believe that the US picked up SABRE for the purpose of modify it to be that future Ma=4 engine in their TBCC. China is doing the same as a parallel option.

I think SABRE refers to the air-breathing rocket engine itself. Its placement within the type of combined cycle engine can be as variable as it were a turbine-based engine.