China's Space Program Thread II

[broadsword]

Nobody talked about the Mengtian booster that fell harmlessly into the Pacific Ocean? Although the descent path was different from Skylab and less controlled, I reckon modern instruments enabled it to be tilted more precisely for a re-entry that eventually turned out to be another big nothingburger.

 

[Kalec]

If they go with the 24x 240t kerolox plan that seems to be the most recent iteration, then I would say it is pretty viable.

If they redesign a single-chamber YF-130 then yes it is pretty promising to finish, but converting a two-chamber design to a one-chamber isn't that simple as split them in half. Then why don't go with YF-135, a more advanced kerolox engine. In short term 240t seems more promising but it is really a waste of time in medium term when CASC could have put more resource into YF-135 and 200t methalox.

Also the model is a two stage rocket, similar to 200t methalox plan instead of the newest 240t kerolox. And the very 120t HO engine has not appeared in any official paper or news outlet yet.

 

[taxiya]

If they redesign a single-chamber YF-130 then yes it is pretty promising to finish, but converting a two-chamber design to a one-chamber isn't that simple as split them in half. Then why don't go with YF-135, a more advanced kerolox engine. In short term 240t seems more promising but it is really a waste of time in medium term when CASC could have put more resource into YF-135 and 200t methalox.

First to list what I know so far:

	Already proven	Challenge	Question mark
YF-135	Turbine and Pump is less challenging, proven by YF130	Combustion chamber has higher thrust, not proven yet
240t kerosene	Turbine and Pump is proven by YF130 Combustion chamber proven by YF130		Is it an ongoing parallel program? If so, the turbine and pump is being developed already just like the combustion chamber of YF-135.
200t methane		It is in 预研 (pre-study), no key tech verification done yet.

If it is a parallel program as YF-130 and 135, its turbine-pump assembly would not be a new thing today. So I think 240t engine could be almost as ready as YF-130, a bit more advanced in progress than YF-135.

Lastly, I think all three paths will continue in full speed, CASC will make the final choice some time around 2025 when they need to finalize the design of the whole rocket and begin to produce.

I don't think time is being wasted. I highly believe that CASC is running all these engine development in parallel with dedicated resources. These teams share knowledges, data and experiences. I would guess that the chief of YF-130, 135 and 240t is the same person.

Also the model is a two stage rocket, similar to 200t methalox plan instead of the newest 240t kerolox.

All the variants have 2 stage and 3 stage configurations. 2 stage for LEO and 3 stage for Moon and Mars.
Here is the 3 stage configuration of the 200t methane engined.

And the very 120t HO engine has not appeared in any official paper or news outlet yet.

It is the same question as for the 240t Kerosene engine. Is it being developed in parallel as YF-90 which is partially proven?

Not seeing any official paper or news should not be any indication. We have seen papers on 200t methane in many years, yet it still does not have official designation. However, YF-135 got the designation only recently without any paper.

 

[Blitzo]

First to list what I know so far:

	Already proven	Challenge	Question mark
YF-135	Turbine and Pump is less challenging, proven by YF130	Combustion chamber has higher thrust, not proven yet
240t kerosene	Turbine and Pump is proven by YF130 Combustion chamber proven by YF130		Is it an ongoing parallel program? If so, the turbine and pump is being developed already just like the combustion chamber of YF-135.
200t methane		It is in 预研 (pre-study), no key tech verification done yet.

If it is a parallel program as YF-130 and 135, its turbine-pump assembly would not be a new thing today. So I think 240t engine could be almost as ready as YF-130, a bit more advanced in progress than YF-135.

Lastly, I think all three paths will continue in full speed, CASC will make the final choice some time around 2025 when they need to finalize the design of the whole rocket and begin to produce.

I don't think time is being wasted. I highly believe that CASC is running all these engine development in parallel with dedicated resources. These teams share knowledges, data and experiences. I would guess that the chief of YF-130, 135 and 240t is the same person.


All the variants have 2 stage and 3 stage configurations. 2 stage for LEO and 3 stage for Moon and Mars.
Here is the 3 stage configuration of the 200t methane engined.
View attachment 101370

It is the same question as for the 240t Kerosene engine. Is it being developed in parallel as YF-90 which is partially proven?

Not seeing any official paper or news should not be any indication. We have seen papers on 200t methane in many years, yet it still does not have official designation. However, YF-135 got the designation only recently without any paper.

One other thing I'd add is that I think the focus on CZ-9 as a project should be to seek the lowest risk, fastest method of achieving a super heavy rocket that has a VTVL first stage reusable compatible design.

Verifying key technologies related to VTVL reusability earlier rather than later is important, and if that means that they might have to develop a new re-engined CZ-9 variant some 5+ years down the line with a more advanced engine, that is fine -- but the important thing is that by that point, they will already have had a super heavy launcher to have done tests or even successful launches for VTVL.


In that context, the 24x 240t kerolox (single chamber YF-130) seems the absolute most sensible option if the goal is for the lowest risk, fastest way of getting a VTVL compatible superheavy.

 

[CrazyHorse]

i-Space Hyperbola-3 reusable launcher.

Some of these are incredibly blatant spacex rip offs.

 

[taxiya]

Some of these are incredibly blatant spacex rip offs.

Is SpaceX Falcon heavy an incredibly blatant ripoff of Delta IV Heavy?
Don't be crazy as you name suggests. You joined this forum less than a month ago just to trash this forum with inflammatory trolling post?

 

[CrazyHorse]

Is SpaceX Falcon heavy an incredibly blatant ripoff of Delta IV Heavy?
Don't be crazy as you name suggests. You joined this forum less than a month ago just to trash this forum with inflammatory trolling post?

No, because the delta lV has many differences. I’m not trying to inflame anything, so I’m not sure why you’re getting angry. The thing with the example I was talking about is that it seems to share basically everything, from the grid fins, the large amount of smaller engines, and the design of the landing legs.

 

[Kalec]

It is the same question as for the 240t Kerosene engine. Is it being developed in parallel as YF-90 which is partially proven?

Not seeing any official paper or news should not be any indication. We have seen papers on 200t methane in many years, yet it still does not have official designation. However, YF-135 got the designation only recently without any paper.

I don't really think single-chamber YF-130 will be quicker compare with YF-135, because as I said it is not simple as splitting engine in half then work done. RD-171 made its first flight in 1985 and RD-180 made its first flight in 2000, 15 years apart and RD-191 in 2014, another 14 years. Russian might be incompetent to split engine in half, at least they are consistent on the timeline.

I don't think China is really in a hurry to launch such heavy rocket anyway. There is a real demand for heavy payload into orbit before 2035, and you can use 921 rocket powered by YF-100N to launch them in parts. Shroud is also too small to put in 150t payload.

	Thrust​	Isp (sea level)	Chamber pressure
YF-130	5000kN	308s	22 Mpa
YF-135	3600kN	312s	27 Mpa
RD-191	1920kN	311s	25.8Mpa
RD-180	3830kN	311s	26.7Mpa
RS-84	4732kN	305s	17.7Mpa

YF-135 will be the ultimate version of kerosene/lox engine, why should CASC develop a generation-behind 240t kerosene for only 5 years use. Suppose we have YF-130half ready to go in 2030 (very optimistic expectation), CASC will need to test YF-135 in 2035 after spending nearly 20 years' development on YF-130 then retiring it in 5 years.

Verifying key technologies related to VTVL reusability earlier rather than later is important, and if that means that they might have to develop a new re-engined CZ-9 variant some 5+ years down the line with a more advanced engine, that is fine -- but the important thing is that by that point, they will already have had a super heavy launcher to have done tests or even successful launches for VTVL.

It would be better and cheaper to test VTVL on YF-100N instead of dedicated-built 240t kerosene. YF-135 may have hit the ceiling of kerosene, China can use it for decades meanwhile developing 200t methane engine for the future vision in space.

 

[anzha]

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[taxiya]

I don't really think single-chamber YF-130 will be quicker compare with YF-135, because as I said it is not simple as splitting engine in half then work done. RD-171 made its first flight in 1985 and RD-180 made its first flight in 2000, 15 years apart and RD-191 in 2014, another 14 years. Russian might be incompetent to split engine in half, at least they are consistent on the timeline.

I personally want YF-135 to be the one chosen for eventual CZ-9, but I think 240t is more like a sibling than a child to YF-130. I hope you are aware that I have said that it is possible that 240t is a parallel program to YF-130 and YF-135. If so 240t is not a split of YF-130 like RD-180 to RD-171. It is a big possibility, but I could be wrong too.