Chinese Space Program (CNSA) & Ch. commercial launch and discussion

[magnemoe]

1 hour ago, steve9728 said:

awwwwww

via. https://weibo.com/1782061332/McTc9EHSE?refer_flag=1001030103_

The model rocket was cute   Suspect the other model is the space station.

[steve9728]

5 hours ago, steve9728 said:

awwwwww

via. https://weibo.com/1782061332/McTc9EHSE?refer_flag=1001030103_

Have to say I wondered if his pictures were photoshopped. Until I saw a video taken behind them:

https://weibo.com/5616492130/Md0SirIZ9

The most he should have done I think was to remove the other unrelated passers-by in the picture. Damn, really sweet

Edited November 1, 2022 by steve9728

[magnemoe]

On 10/25/2022 at 1:02 PM, steve9728 said:

Weird... a large, four engines, multipurpose, medium-altitude, long-endurance fixed-wing UAV, Two-tailed Scorpion D from Tengden company. Was successfully finished its maiden flight.

  Hide contents

"The aircraft has wingspan 20m, length10.5m, height 3.1m, maximum take-off weight 4.35t, maximum load weight 1.5t and a maximum loading space 5m³". They also said that this new UAV will be exhibiting at the Zhuhai Airshow.

Stunning

You don't see twin boom aircrafts like the P-38 lightning often and with 4 engines I say its very rare.  weirder in that the center fuselage extend all the way to the tail. 
Assume its an huge radar back there and they did not want the structure and controls for the tail to interfere with it.

[steve9728]

13 minutes ago, magnemoe said:

You don't see twin boom aircrafts like the P-38 lightning often and with 4 engines I say its very rare.  weirder in that the center fuselage extend all the way to the tail. 
Assume its an huge radar back there and they did not want the structure and controls for the tail to interfere with it.

And looking at the fuselage, if they paint a Antonov logo on it, I don't feel strange at all! First impression is that this thing feels like 'AN-1.24'  to me hahaha

If they have a six engines plan... well... AN-2.25

Edited November 1, 2022 by steve9728

[tater]

 

[mikegarrison]

35 minutes ago, tater said:

 

Well that's certainly helpful. "Re-entry will be somewhere in the world". I mean, OK, it looks like my house is safe. But still...

[tater]

It'll narrow as it gets closer, but yeah, the roulette wheel has much of Earth in play.

[SunlitZelkova]

The spaceplane (Shenjian?) may be coming back to Earth soon, along with the core stage.

[RCgothic]

Due to inclination the densest portion of the ground tracks is over the US and North Atlantic, and the southern Indian Ocean.

[Codraroll]

12 hours ago, mikegarrison said:

Well that's certainly helpful. "Re-entry will be somewhere in the world". I mean, OK, it looks like my house is safe. But still...

Somewhere in the world, yes, but strictly bound to those orbital lines. Looks like the west coast of India is off the table, for instance. 

[steve9728]

13 hours ago, SunlitZelkova said:

The spaceplane (Shenjian?)

Shenjian is the CZ-2F rocket. That one is Reusable Experimental Spacecraft, or just simply Tengyun. But when it can come back... I don't dare to know. The thing I only hope is I can watch a documentary about it 30 years later.

That could use the patches on my avatar to describe this: If you steal the secret, you will be caught. If you been caught, you will be killed. Everyone please tries your best to catch the enemy spy. If you catch them, you will get a hell of credit. This patch actually is from a billboard at the entrance of PLAAF's Dingxin test flight base, which is near to the Jiuquan Satellite Launch Center.

 

According to the live preview of the CCTV's app, the Mengtian Module's transposition manoeuvre will start at 9am CST

Spoiler

I'll definitely will be showing this live on the office's projector tomorrow morning

[steve9728]

On 11/2/2022 at 12:46 AM, magnemoe said:

Assume its an huge radar back there and they did not want the structure and controls for the tail to interfere with it.

Add: I thought that YouTube don't have its video, and that's wrong. It has two cargo holds front and rear.

[tater]

A space program capable of landing on Mars can properly dispose of rocket stages. Amazing that they chose not to.

 

[steve9728]

19 minutes ago, tater said:

A space program capable of landing on Mars can properly dispose of rocket stages. Amazing that they chose not to.

 

CNSA can add a YZ-2 upper stage on the CZ-5B rocket and that's also the plan in the future how to use it. But upper stage has its own weight: maximum 8t. The CZ-5B rocket can take 25t to LEO. Every module of CSS is around 23t: I'm pessimistic that the upper stage will make it to orbit if it uses up the remaining two tonnes of capacity of the rocket along with its fuel. Not to mention the length of the fairing as well.

It's a bit selfish to say that but it's just the "lesser of two evils". And I don't think the Xuntian telescope can make it to 20 tones. Probably we can see a good boy next time

Edited November 2, 2022 by steve9728

[steve9728]

Surprising to me is there also have kids from Vietnam

[Beccab]

22 minutes ago, steve9728 said:

CNSA can add a YZ-2 upper stage on the CZ-5B rocket and that's also the plan in the future how to use it. But upper stage has its own weight: maximum 8t. The CZ-5B rocket can take 25t to LEO. Every module of CSS is around 23t: I'm pessimistic that the upper stage will make it to orbit if it uses up the remaining two tonnes of capacity of the rocket along with its fuel. Not to mention the length of the fairing as well.

It's a bit selfish to say that but it's just the "lesser of two evils". And I don't think the Xuntian telescope can make it to 20 tones. Probably we can see a good boy next time

That's not the only way to do it - a much simpler option if you need your core stage to reach orbit for whatever reason is to add a small deorbit motor to it. Back when the Shuttle configuration was chosen (SRBs+external tank+side mounted orbiter) the original plan was to take the ET to orbit; but NASA wouldn't have left it there. Do you see that weird extension on top of the tank in this early artwork?

That's a solid motor meant to deorbit the stage after orbital insertion. The launch sequence was later changed to separate from it prior to orbital insertion and complete it with the OMS, but both plans work still. Hell, you can even just add separation motors at the bottom of the stage like the first stage of the Saturn V if you need, there's a ton of possibilities to solve this. The CNSA didn't have to keep it in orbit, they chose to.
Hell, even the Soviet Union almost always tried to deorbit their own stuff in a controlled manner, including all Salyut stations; salyut 7 wasn't controlled because, much like skylab, it was boosted to wait for Buran but it took too long and Salyut 2 was basically destroyed by the explosion of the stage that launched it.

[steve9728]

10 minutes ago, Beccab said:

they chose to

On 10/31/2022 at 1:12 PM, steve9728 said:

No room for error because there's a typhoon incoming

Currently here the typhoon still there (a little bit up left) and it's looks like around 14 hours (?) to drop. Somehow, I want to see what it will happened if it drops in the typhoon. But that would be quite dangerous for me hahaha

Not only CNSA or PLA or something else, but also all state-run organizations have a strange rule about "Modifications to the original design should be made with extra care and attention." Quite annoying I admit. I can only understand it in the way that "behind every strange rule there is at least one human life".

Edited November 2, 2022 by steve9728

[tater]

2 hours ago, steve9728 said:

CNSA can add a YZ-2 upper stage on the CZ-5B rocket and that's also the plan in the future how to use it. But upper stage has its own weight: maximum 8t. The CZ-5B rocket can take 25t to LEO. Every module of CSS is around 23t: I'm pessimistic that the upper stage will make it to orbit if it uses up the remaining two tonnes of capacity of the rocket along with its fuel. Not to mention the length of the fairing as well.

It's a bit selfish to say that but it's just the "lesser of two evils". And I don't think the Xuntian telescope can make it to 20 tones. Probably we can see a good boy next time

Then cut the payload mass or build a better rocket. If the 23t modules can't be lofted with disposal, make 22t modules. Or 20t—whatever it takes.

Every single launch vehicle on Earth has a max payload that would be slightly increased by not disposing of stages.

 

[SunlitZelkova]

6 hours ago, tater said:

A space program capable of landing on Mars can properly dispose of rocket stages. Amazing that they chose not to.

I was thinking about this and realized they are probably influenced by the launch of Skylab. The S-II put it into orbit and stayed there for two years.

https://www.drewexmachina.com/2022/07/31/rockets-falling-from-orbit-the-saturn-v-that-launched-nasas-skylab/
 

It wasn’t responsible then but… the Skylab decision certainly makes it look ok to be irresponsible.

[tater]

Phobos-Grunt was a failure, not intentional. So no one has allowed large things to just randomly reenter for 30 years.

There's not any excuse for it.

 

[steve9728]

Start

The procedure takes 30 minutes to carry out, which is almost 3° of rotation a minute.

Add: the crew will enter the module at 14:00 CST

5 hours ago, tater said:

Then cut the payload mass or build a better rocket. If the 23t modules can't be lofted with disposal, make 22t modules. Or 20t—whatever it takes.

Every single launch vehicle on Earth has a max payload that would be slightly increased by not disposing of stages.

 

Then you need to consider is let the modules take less fuel, or copy a CBM like docking mechanism to let 1 or 2 Tianzhou take the experiment racks up to the station. Currently CNSA have the large diameter hatch tech, but not the docking mechanism. If less fuel is carried, the existing plans for orbit entry and circularisation of the orbit may not even be fully achieved. If less payload taken, then the whole project might as well not have been done.

I agree with the idea of bringing a (or some) solid rocket, and that's what I would do in the KSP. It would have to be considered where to put it though: if it's on the exterior of the rocket shell, there are certain aerodynamic implications that would have to be considered; if it's mounted somewhere between the rocket and the module, I don't think there's enough room:

The black adapter inside is the rear docking mechanism. There are also a number of precision devices here.

Edited November 3, 2022 by steve9728

[steve9728]

Done

[tater]

21 minutes ago, steve9728 said:

Then you need to consider is let the modules take less fuel, or copy a CBM like docking mechanism to let 1 or 2 Tianzhou take the experiment racks up to the station. Currently CNSA have the large diameter hatch tech, but not the docking mechanism. If less fuel is carried, the existing plans for orbit entry and circularisation of the orbit may not even be fully achieved. If less payload taken, then the whole project might as well not have been done.

Responsible deorbiting stages is a price of admission, unless a country wants to be rightfully accused of being a danger.

We all understand the tyranny of the rocket equation reasonably well. The reality in this case is that disposal is pretty trivial. Leave the perigee low in the disposal area, then raise it with just a few m/s by the spacecraft. For Shuttles doing direct insertion, the OMS burn was sometimes under 100 fps (~30 m/s).

So the dv requirement to be responsible is trivial.

(ISS missions were maybe 250 fps, so ~75 m/s)

https://ntrs.nasa.gov/api/citations/20110001406/downloads/20110001406.pdf

 

(every single shuttle mission, OMS burns are listed in duration and fps).

Edited November 3, 2022 by tater

[steve9728]

6 minutes ago, tater said:

So the dv requirement to be responsible is trivial.

I'm actually kinda hoping that CNSA will replicate a CBM like docking mechanism. And to be honest, I don't really like the idea of an airlock on top of the node. If in KSP I would put the CBM on the airlock position for the Tianzhou also with the CBM. Both Wentian and Mengtian using another two CBM to dock with the station in both sides. But that would make me 'break the rule' deeply:

7 hours ago, steve9728 said:

"Modifications to the original design should be made with extra care and attention."

Shrug*

[steve9728]

They've got their hands full these days: too many parcels!

A minor hiccup, the live news presenter was on her way to interact with two principals from the CNSA when the presenter suddenly received a headset saying that her was connected to the station. There was a strange sense of tension on the ground and people in the station hahahahaha

Edited November 3, 2022 by steve9728