China's Space Program News Thread

[taxiya]

Please keep in mind that these kind of generalizations don't help the conversation in my honest opinion. In any case, if you are really interested in the subject at hand:

1. Whataboutism has no place in these forums. Two things can be bad at the same time.

2. What was acceptable with the tech and specifics of the 70's is certainly not acceptable now.

3. The 1979 Skylab debacle was not acceptable. It was a major incident with big ramifications that informed thereafter some of the tech and specifics I mention in 2.

4. Skylab was purposefully de-orbited but the then state of the art (with regards to material burn rates) resulted in a landfall miscalculation. 40+ years later, 2021-035B is reported as tumbling uncontrollably in space. And this is the second time for this specific variant.

Is this acceptable in 2021?

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This is incorrect, it has a lot of choices. All modern upper stages have the ability to alter their orbit as part of the pacification process post-separation.

Where is the modern choice for spaceX's upper stage?

Why a Chinese rocket is a concern while a American rocket is not equally a concern? This is about your "whataboutism".

 

[Dante80]

Where exactly have I said that an American rocket that de-orbits in an uncontrolled manner is not a concern?

Please guide me to said post now, or desist immediately and apologize as you should.

 

[taxiya]

Falcon Heavy style rocket intended for moon mission.
View attachment 71612
921 rocket on the right

Some people speculates that this rocket could be made reusable just like Falcon Heavy.

And @Deino

A minor detail about 921.

921 is the name of a program. The program calls for a crew rocket for the Moon mission. There were two proposals. One from 1st academy shown here on the left, another from 8th academy. All of them are 921 rockets, the final chosen rocket would gain a CZ designation.

The 8th academy proposal is something like Angara. It's diameter of first stage is 3.8 meters. It's second stage is 5m. It is a five booster CBC configuration. So far the only published progress is the first stage tank made in 2020.

It seems that the choice has been made due to the publicity in various exhibition.

 

[taxiya]

Where exactly have I said that an American rocket that de-orbits in an uncontrolled manner is not a concern?

Please guide me to said post now, or desist immediately and apologize as you should.

If you expect an answer, you should directly reply to that post to get the attention.

That being said, I assume that your post was intended for me, right?

You did not say so (the underlined text), but you implied so by singling out Chinese rocket as unacceptable while ignoring all the many same things of rockets from other countries. Didn't you? If everybody is doing the same thing up until 2021, then there should be nothing special worth to mention about CZ-5B's core stage, therefor you should not have posted what you did in the first place.

You are being biased and making selective judgement. For that, there is nothing to apologize, and I will only reiterate my point.

 

[Dante80]

You did not say so (the underlined text), but you implied so by singling out Chinese rocket as unacceptable while ignoring all the many same things of rockets from other countries. Didn't you? If everybody is doing the same thing up until 2021, then there should be nothing special worth to mention about CZ-5B's core stage, therefor you should not have posted what you did in the first place.

Implied? Again, no. I am very specific with my words when commenting on matters I am both familiar with and interested at.
Don't put words in my mouth. This is the second time that someone says that I implied something different than what I contributed.

This is the Chinese Space Program News thread and I was specifically replying on a news item. I shouldn't have posted in the first place without preliminarily whitewashing or trivializing the incident? Are you for real?? Biased? Selective judgement?

In any case, I will still assume good faith from you and reply, even when you didn't apologize. This is my last post on this specific subject though, don't quote me with a question again. They either fucked up by not attempting to fix the problem, or simply a technical error made the intended de-orbit maneuver post-separation to fail. In any case, this is regrettable.

TWO THINGS CAN BE BAD AT THE SAME TIME. THE FACT THAT ONE EXISTS DOES NOT MEAN THE OTHER IS NOW JUSTIFIED.

 

[Dante80]

In other news, every single major operations in the construction of the CSS through to late 2022:
(from Chinese social media - I'm not sure of its original source but it looks legit)

 

[Dante80]

Moreover, Some updates on new rockets.

First, SAST's new medium Commercial launcher (consider it similar to F9 v1.0?). Tentative maiden flight is scheduled for 2023.
Height: 59m. Take-off weight: 433t. Take off thrust: 5000KN.
LEO@300km: 10T, SSO@700km: 5t
First stage: 4 * YF100k engines, second stage: 2* YF115

This rocket is believed to be the single core version for SAST's 921 rocket (5*4 YF100K with 3.8 diameter)

 

[Dante80]

Here are some presentation slides from China Space Day. Sorry if some have been already posted.

First image is the comparison of YF-100, YF-100K, YF-100M (vac)
YF 100K:
Throttle range: 65% to 105%; Thrust to Weight ratio: 75

YF-100M: nozzle diameter: 2.16m, nozzle ratio: 90

Second image has a comparison of two New gen manned launcher on the right. Left one is CALT's 3*7 YF-100k version, and the right one is SAST's 5 * 4 YF100K version. Both use 2 * YF100M for the second stage.

Also, on the left, there are notations showing 2025 crewed lunar fly by mission and 2030 crewed lunar landing mission...

The third one showing the diameter of CALT's launcher is 5m with 27t LTO

 

[Dante80]

The last one is 200t LOX/methane engine

low-cost full-flow stage combustion
throttle range: 25% -110%
sea level thrust: 2000kN
sea level impulse: >= 327s
Thrust to weight ratio >= 90
could be reused for >= 20 times

The second image shows possible config for this engine. 5m diameter with 3 or 5, and 7.5m diameter with 9

 

[gelgoog]

The last one is 200t LOX/methane engine

low-cost full-flow stage combustion
throttle range: 25% -110%
sea level thrust: 2000kN
sea level impulse: >= 327s
Thrust to weight ratio >= 90
could be reused for >= 20 times

... 5m diameter with 3 or 5, and 7.5m diameter with 9

View attachment 71634

This is really impressive. If they put this rocket engine into service they will have an engine with twice the power and much deeper throttling than the YF-100. For comparison this will have similar thrust to the Raptor engine with much deeper throttling capabilities. The 5 engine version would have more power than the Falcon 9 while using similar tooling and transport facilities to the ones used in the CZ-5.

These would be basically replacements for all the major rockets CZ-7/CZ-8, CZ-5, CZ-9 with a common first stage engine.