China's Space Program Thread II

pevade

Junior Member
Registered Member
Yes it seems China will have to stop using those highly toxic hypergolic fuel rockets soon. The newer rockets they have designed and put into service doesnt seem to in use much, apart from a few missions here and there. They seem to be more focus on launching high numberd of hypergolic fuels that have been in use since the 90s. I believe it's easier to do so than using newer ones, which need new infrastructure and support system in place in large numbers to replace those old rockets, that's without counting the cost of doing so. So i suppose they have their reasobs for sticking with those old hypergolic highly toxic rockets . We are not in a position to judge.
There are several newer rockets in development but AFAIK there is no designated replacement for the CZ-2F (human rated spacecraft) which is an issue.
 

taxiya

Brigadier
Registered Member
There are several newer rockets in development but AFAIK there is no designated replacement for the CZ-2F (human rated spacecraft) which is an issue.
Two stage CZ-10 is the replacement for CZ-2F.
The Long March 7 has similar performance characteristics to the Long March 2F.
CZ-7 was envisioned to replace CZ-2F (at the latest as 2014), but it is clear by now that role is given to CZ-10.
 

gelgoog

Brigadier
Registered Member
That is because they plan to switch from Shenzhou to the new capsule.
Shenzhou has 8100 kg mass and the new capsule has 14000 kg mass. It is almost twice as heavy.
That makes the new capsule too heavy for something like CZ-2F or CZ-7.

Shenzhou is similar to Soyuz capsule design, while the new capsule is similar to the Apollo capsule design.
The Soyuz capsule design is way more weight efficient, because it has the separate orbital space module.
But the orbital space module is not reusable. It is meant to be ejected on reentry. So if you want a reusable space capsule you get something like the Apollo capsule design.

The Russians just take the electronics inside the Soyuz capsule after it lands and reuse them. The rest of the Soyuz capsule is just trashed and they make a new one. But there are Russian plans to make a similar capsule to the new Chinese one i.e. Orel.

The new capsule is also larger because they plan to use the same base design for long duration and lunar missions. The base Soyuz design is capable of being used for lunar missions as well, but IIRC the Soviets planned to make a two man mission to the moon, with just one man landing. Not three men, with two men landing like on Apollo.
 
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by78

General
The private launch company
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has successfully completed a hot run of its LY-70 LOX/Methane engine connected to a stainless steel propellant tank developed by Beijing Jianyuan Technology (箭元科技). The propellant tank is low-cost, re-usable, and has a diameter of 4.2m.


52637397490_9c0651f003_k.jpg

The private launch company
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has successfully completed the first round of reliability assessments of its 70-ton reusable LY-70 LOX/Methane engine. The engine has accumulated more than 116 minutes of hot test runs (with single longest test run having exceeded 61 minutes) and demonstrated variable thrust range of 32% to 106% (215kN to 720kN).

Some design specifications of LY-70 are as follows:
- Ground thrust: 686.5kN
- Vacuum thrust: 770.2kN
- Ground specific impulse: 291.2s
- Vacuum specific impulse: 350s
- Engine mass: no greater than 880kg
- Maximum swing angle: ±8°
- Adjustable thrust range: 30% to 110%
- Single-mission engine restarts: ≥3 times
- Reusability: ≥30 times

52921449909_8b2cb99f94_o.jpg
52921287461_e6a34ee021_o.jpg
 

by78

General
Some presentation slides on the heat resistant material used on the
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(à la Sino X-37B). The material has been applied to the leading edge and the landing gear doors of the spacecraft.

The Chinese heat resistant material has a density of between 0.32 and 0.54 grams per cubic centimeter, which falls somewhere between
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and
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, but its thermal conductivity is significantly lower (only 0.08 W/mK) compared to AVCOAT (0.16) and PICA-X (0.3). It's also easier to manufacture and has far superior compressive and tensile strength as well as superior toughness. The material can be fashioned into far larger parts/tiles than foreign competitors.

The third slide states that the reusability of the material is greater than 77%, presumably meaning that more than 77% of heat-resistant/ablative tiles can be reused for another mission. This was demonstrated in August of 2018 when the spacecraft returned to Earth, and out of the 1275 tiles(?), only 286 needed to be replaced.

By the way, the first image below is the very first close-up photo of the mysterious Chinese spaceplane that I have come across.

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52921437561_4781a8dd2a_o.jpg
52921823695_ef6c8ff0c4_o.jpg
 
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Cybertron42

Just Hatched
Registered Member
The private launch company
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has successfully completed the first round of reliability assessments of its 70-ton reusable LY-70 LOX/Methane engine. The engine has accumulated more than 116 minutes of hot test runs (with single longest test run having exceeded 61 minutes) and demonstrated variable thrust range of 32% to 106% (215kN to 720kN).

Some design specifications of LY-70 are as follows:
- Ground thrust: 686.5kN
- Vacuum thrust: 770.2kN
- Ground specific impulse: 291.2s
- Vacuum specific impulse: 350s
- Engine mass: no greater than 880kg
- Maximum swing angle: ±8°
- Adjustable thrust range: 30% to 110%
- Single-mission engine restarts: ≥3 times
- Reusability: ≥30 times

52921449909_8b2cb99f94_o.jpg
52921287461_e6a34ee021_o.jpg
61 min. in a single test run? How? Do you have any source for it?
 

anzha

Senior Member
Registered Member
Some presentation slides on the heat resistant material used on the
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(à la Sino X-37B). The material has been applied to the leading edge and the landing gear doors of the spacecraft.

I find the Western media can be hilarious at times. Here the Chinese are being very upfront, more so than the US, about their spaceplane, and we get articles scribbling away about how mysterious China is being with their bird and their entire program. The USAF doesn't say boo about their own bird and far fewer bloviate over it. Here, the Chinese are presenting about their own work outright.

For example:

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or...

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It appears to me that the Chinese are as open as the US, but journalists are outright lazy.
 

vincent

Grumpy Old Man
Staff member
Moderator - World Affairs
I find the Western media can be hilarious at times. Here the Chinese are being very upfront, more so than the US, about their spaceplane, and we get articles scribbling away about how mysterious China is being with their bird and their entire program. The USAF doesn't say boo about their own bird and far fewer bloviate over it. Here, the Chinese are presenting about their own work outright.

For example:

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or...

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It appears to me that the Chinese are as open as the US, but journalists are outright lazy.
Nope, they have a KPI (smear China) to meet
 
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