totm dec 2019 Russian Launch and Mission Thread

[kerbiloid]

20 minutes ago, CatastrophicFailure said:

Building tanks strong enough to survive a given impact is a known and relatively solvable engineering problem.

That's fine, and where is a ground crash test of the Dragon?

[CatastrophicFailure]

8 minutes ago, kerbiloid said:

That's fine, and where is a ground crash test of the Dragon?

They’ve done upwards of 10+ ground landing tests of varying fidelity. I trust they have the data they need to design things to needed specification. 

[kerbiloid]

57 minutes ago, CatastrophicFailure said:

They’ve done upwards of 10+ ground landing tests of varying fidelity. I trust they have the data they need to design things to needed specification. 

The ground hit on landing at 20 m/s without legs is 30...40 g.
With legs - 20 g.
(From the calculation of the PTKNP landing system)

Crew Dragon is probably ~10 m/s. Apollo had a special honeycomb for the ground case.
And tanks themselves are not the most fragile part. The pipes are.
It has heavy tanks and eight sets of pipes, with self-flammable toxic fuel.

All others avoid this for any cost for reasons.

Edited April 30, 2021 by kerbiloid

[SOXBLOX]

Why are we debating the structural integrity of Crew Dragon? It already completed its drop tests, and it splashes down in the water, anyway. 

Other capsules like Soyuz or whatever don't have fuel on the spacecraft because they don't recover their engines, not because it's a safety hazard.

[CatastrophicFailure]

19 minutes ago, kerbiloid said:

The ground hit on landing at 20 m/s without legs is 30...40 g.
With legs - 20 g.
(From the calculation of the PTKNP landing system)

Crew Dragon is probably ~10 m/s. Apollo had a special honeycomb for the ground case.
And tanks themselves are not the most fragile part. The pipes are.
It has heavy tanks and eight sets of pipes, with self-flammable toxic fuel.

All others avoid this for any cost for reasons.

And these are all very solvable engineering problems. It’s not that difficult to design tanks that are stronger than the crew. If the impact kills the crew, what happens to the tanks doesn’t really matter. If the crew can survive a hard landing, so can the tanks. 

1 minute ago, SOXBLOX said:

Why are we debating the structural integrity of Crew Dragon? I

Kerbals have a thing for squirrels... 

[SOXBLOX]

1 minute ago, CatastrophicFailure said:

And these are all very solvable engineering problems. It’s not that difficult to design tanks that are stronger than the crew. If the impact kills the crew, what happens to the tanks doesn’t really matter. If the crew can survive a hard landing, so can the tanks. 

Precisely! Fighter jets could take more g-force than a man since shortly after WWII. Obviously, so could their fuel tanks.

[kerbiloid]

33 minutes ago, SOXBLOX said:

Why are we debating the structural integrity of Crew Dragon?

Because after I had posted a post with description of the planned orbital station, somebody ran the thread into offtopic about the Russian technological consistency.

33 minutes ago, SOXBLOX said:

Other capsules like Soyuz or whatever don't have fuel on the spacecraft because they don't recover their engines, not because it's a safety hazard.

Nobody except SpaceX ever had in thought placing engines into the crew capsule. Because it's not a spaceplane.

32 minutes ago, CatastrophicFailure said:

And these are all very solvable engineering problems. It’s not that difficult to design tanks that are stronger than the crew. If the impact kills the crew, what happens to the tanks doesn’t really matter. If the crew can survive a hard landing, so can the tanks. 

Planes and choppers crash, but crew survives when the metal is crashed.

30 minutes ago, SOXBLOX said:

Fighter jets could take more g-force than a man since shortly after WWII.

Than a man getting asleep. Nobody needs a plane stronger than a crew.

***

Spaceship won't be used in the Russian space program by definition, if it will ever fly or not. 

Isn't this enough itself?

(In the Chinese one, too, in case if somebody wants to start the next round.

As well in the space program of any country with its own space rockets.)

We'll see if it will be used at least by NASA, if/when it gets ready.

Edited April 30, 2021 by kerbiloid

[tater]

NSF article:

https://www.nasaspaceflight.com/2021/04/roscosmos-future-for-mid-2020s/

Another image I found on twitter:

 

[CatastrophicFailure]

4 hours ago, kerbiloid said:

Nobody except SpaceX ever had in thought placing engines into the crew capsule. Because it's not a spaceplane.

5 hours ago, CatastrophicFailure said:

Ahem: 

Spoiler

Until such designs, there was no need to. 

4 hours ago, kerbiloid said:

Planes and choppers crash, but crew survives when the metal is crashed.

You said it yourself:

4 hours ago, kerbiloid said:

Nobody needs a plane fuel tank stronger than a crew.

It’s not a difficult design feat to make a tank that can survive the same impact a crew could. The tank need not be stronger than the crew. This is old tech. 

[SOXBLOX]

So, if there are design flaws in SpaceX's vehicles, we haven't seen them yet. Aside from a couple early prototypes crashing, when they were basically intended to crash, their stuff is solid. Besides this, it flies regularly. That's something not everyone can say. If Starship works, and it seems like it will, at least for cargo, then it would be in Roscosmos's best financial interests to use it. But @kerbiloid is right, they won't.

5 hours ago, kerbiloid said:

Nobody needs a plane stronger than a crew.

And yet, every modern fighter jet can take more g-force than a human can sustain. I guess those engineers at Lockheed Martin and Mikoyan-Gurevich are total suckers. 

[insert_name]

4 hours ago, tater said:

NSF article:

https://www.nasaspaceflight.com/2021/04/roscosmos-future-for-mid-2020s/

Another image I found on twitter:

 

 

It looks like pirchal with the delivery progress still attached, and an airlock on the end, a far cry from what the article is describing, that must just be the core module

[kerbiloid]

6 hours ago, tater said:

Another image I found on twitter:

  

1 hour ago, insert_name said:

It looks like pirchal with the delivery progress still attached, and an airlock on the end

What is the horrible horror on this picture?!

It's  the airlock&docking module for ISS/ROSS/LOP-G(before they left).

Spoiler

The picture is not fully relevant.
The narrow end could, of course, carry the IDSS port for LOP-G, but won't for the Russian station, as it doesn't use it.
There should be the "hybrid" active port with the probe, to attach it to the passive port of the station having the drogue.
Also, the artist copypasted the IDSS one with targets which are useless, as it will dock to the station, not something will dock to it.

Why do three Soyuzes have a need to dock to it?
It should be delivered by Progress, of course, but with the headless Progress. Just the propulsion unit.
Where does it take power from? It doesn't have its own source.
The module is to be docked to the station with the active port on its narrow end. How did Soyuz dock to the active port? And why?
Will this fly to Alpha Centauri?

The artists are such artists...

5 hours ago, CatastrophicFailure said:

Until such designs, there was no need to. 

1. Any of them ever flied?
2. They are not reentry capsules, they are whole rocketships.

5 hours ago, CatastrophicFailure said:

It’s not a difficult design feat to make a tank that can survive the same impact a crew could. The tank need not be stronger than the crew.

Any video of Crew Dragon crash test with fueled tanks without chutes?
(I mean, from a crane, of course, not from the chopper, lol).
I can google only Cargo on chutes.

I believe, Boeing and LockMart know what they do.

4 hours ago, SOXBLOX said:

Besides this, it flies regularly.

It flied three times, and landed splashed once.
Upd. one time more without crew.

4 hours ago, SOXBLOX said:

If Starship works, and it seems like it will, at least for cargo, then it would be in Roscosmos's best financial interests to use it.

It will never be in someone's having his own rocket program  interest. And couldn't be.
Because:
1. Dependency on a foreign developer. Tomorrow US will deny its usage, and so what then? So, no way by definition.

2. Monopoly. The lower is competition, the greater are prices. No alternative rockets - SpaceX will set Martian prices for any launch.
Angara problems are caused by competition between two manufacturers and rocket families: Angara and next-Soyuz, that's all.
The engines go normally.
Even without them, there is not a big problem to restart the classic rocket from 1960s, Proton. It's not a Saturn V, it flied many hundreds of times.

3. No shuttles - no flies. 
Don't you forget how the US astronauts were flying to the ISS on Soyuzes for a decade?
It's just the second non-Russian ship on the ISS now after a whole decade.
If somebody here remembers, the shuttle was already "the only, the cheapest, the wisest, the most capable".
And see, what happened instead? The most expensive launch vehicle in history, stopping flights twice. The second time - for decade.

 

4 hours ago, SOXBLOX said:

they won't.

Nobody won't, who has at least smaller rockets.
The South-Asian countries will, because they don't have, so don't care.
The South America, probably.

Try to convince France to scrap Ariane because there "is" Starship.
Try to convince China to replace Long March. Why not? It's definitely not better, and terribly hypergolic.

ESA, as we can see, tends to join any foreign space program they can. American, Russian, Chinese. Why not stick totally to Starship?

Because it's always much better to have your own than depend on a monopolist and his greed.

Nobody needs Starship except USA, and I'm sure that Boeing, Lockmart, and several others would argue even with that.

Also it has a major irrepairable defect: it doesn't use SRB.
While it's normal for Russia and China, the American rocket not using SRB steals the last piece of bread from the all-mighty ballistic rocket monopolist Thiokol.
This is immoral and inappropriate, I believe.

So, actually nobody needs Starship except NASA.

4 hours ago, SOXBLOX said:

And yet, every modern fighter jet can take more g-force than a human can sustain. I guess those engineers at Lockheed Martin and Mikoyan-Gurevich are total suckers. 

To get unconcscious, a human needs 9 g.
To crash bones, he needs 30 g.
Never heard about 30 g airplanes, but when in 1980s they were planning to build an overmaneuvering fighter able to strafe, they cancelled this study because it was possible to build such fighter, but made no sense if the pilot is unconscious.

Edited May 1, 2021 by kerbiloid

[SOXBLOX]

Okay. Here's my problem with your logic. It boils down to the fact that you are saying, "It has never been done this way before, ergo, it is wrong and will fail." By that logic, the Wright Flyer should never have flown, Soyuz should never have flown, and Apollo's LM should never have lifted off from the Moon.

I think that in @kerbiloid's version of Star Trek, or The Expanse, we would see Soyuz docking to the Enterprise or Rocinante. 

[kerbiloid]

16 minutes ago, SOXBLOX said:

"It has never been done this way before

for reaons, and the reasons haven't gone".

 

Spoiler

 

16 minutes ago, SOXBLOX said:

I think that in @kerbiloid's version of Star Trek, or The Expanse, we would see Soyuz docking to the Enterprise or Rocinante

 

@kerbiloid doesn't understand how can one seriously watch ST after 1960s, and thinks it's a specific national American tradition, like a turkey.
So, there could not be a ST version of him.

Also, he would never use the name Rocinante, as he can't see anything charming in the Don Quixote story, and thinks it a similar Spanish tradition.

Also he is not a fan of Soyuz. It should be replaced in early 1970s with other ships (TKS, LKS, Soyuz-VI), but for some known reasons this didn't happen.

But this is even greater offtopic and we should not be discussing my preferences in this thread.

 

[tater]

1 hour ago, kerbiloid said:

What is the horrible horror on this picture?!

It's hard to find decent images.

Another couple:

 

Straight renders would be cool, obviously. Just can't find them.

[kerbiloid]

1 minute ago, tater said:

It's hard to find decent images.

Thanks, I see that this was the airlock&docking module in the middle, I meant what the bacchanalia was happening on that picture.

[YNM]

On 5/1/2021 at 2:40 AM, kerbiloid said:

The ground hit on landing at 20 m/s without legs is 30...40 g.
With legs - 20 g.
(From the calculation of the PTKNP landing system)

Crew Dragon is probably ~10 m/s. Apollo had a special honeycomb for the ground case.
And tanks themselves are not the most fragile part. The pipes are.
It has heavy tanks and eight sets of pipes, with self-flammable toxic fuel.

Do you not understand how LES works or what ?

1. A mishap occurs, and LES need to be activated. LES engines fire, emptying all the fuel from the capsule (or dedicated LES tower to then be jettisoned), and avoiding LOC due to mishap. Capsule lands w/o any fuel on board.

2. Successful launch. Remaining fuel used for maneuver and de-orbit, as well as vented out before re-entry, in the case of SpX - or in every other capsule design before it, they were jettisoned away during launch, and the maneuvering fuel will later be vented off again. Capsule lands w/o any fuel on board after being in orbit.

3. An explosion/mishap occur and the LES fails. Full LOC, regardless of the design chosen. (even worse if you never had LES in the first place.)

If you feel like they're 'cheating' with the amount of fuel, that's actually because they understand that fuel not used for LES ops is fuel available to do *anything else* :

a. If you use LES fuel then you'll never use maneuvering fuel.

b. If you use maneuvering fuel then you probably never needed that LES fuel which you had to jettison.

They simply look at the truth and devised a way so that the fuel is used exactly only in one case and there isn't any for the other.

Edited May 1, 2021 by YNM

[kerbiloid]

28 minutes ago, YNM said:

Successful launch. Remaining fuel used for maneuver and de-orbit

They can't know how much fuel will rest after the deorbit and aren't able to pump it from Dragon to ISS.

They need some fuel for control attitude during the aerobraking.

So, they have some hardly predictable amount of fuel after aerobraking, on landing, and have those tanks below the cabin on touchdown, whereveer it happens.

Also they have the heavy engines and their pumps, attached to the capsule. Eight of them. It's hard to overcomplicate more, and to create more potential crash points.

28 minutes ago, YNM said:

They simply look at the truth and devised a way so that the fuel is used exactly only in one case and there isn't any for the other.

They simply made a fetish out of the reusability and tried to stick it into everything, including (try to call this healthy) the shroud sections.

There was only one such project more, Zarya.
But happily cancelled long before it started being implemented.

Spoiler

 

Edited May 1, 2021 by kerbiloid

[YNM]

16 minutes ago, kerbiloid said:

They need some fuel for control attitude during the aerobraking.

So, they have some hardly predictable amount of fuel after aerobraking, on landing, and have those tanks below the cabin on touchdown, whereveer it happens.

Pretty sure you can reduce the amount of fuel only down to the amount you need. Otherwise they wouldn't have been able to de-orbit (venting fuel is really just opening the prop valves AFAIK)  or had to do away with active attitude control of the capsule for re-entry. (Soyuz has had to do quite a number of the latter.)

 

Also, doing away with dedicated LES fuel means that you can put in more payload instead, or you can use less fuel for the launch. It's due to the rocket equation, not reusability.

Edited May 1, 2021 by YNM

[SOXBLOX]

14 hours ago, kerbiloid said:

...specific national American tradition...

It's even more popular in Germany, so...

15 hours ago, kerbiloid said:

Nobody won't.

Exactly. 

15 hours ago, kerbiloid said:

the all-mighty ballistic rocket monopolist Thiokol.

Northrop Grumman is doing fine, TY. They have the contract to build GBSD (Minuteman IV? I wonder what they'll name it.). Anyways, they have no hold on SpaceX's funding.

11 minutes ago, kerbiloid said:

They simply made a fetish from the reusability and tried to stick it into everything, including (try to call this healthy) the shroud sections.

Does your city trash its buses after every use? Reusability works. That's why so many of the rockets designed for the future are reusable, or at least partially so.

Edited May 1, 2021 by SOXBLOX

[kerbiloid]

4 minutes ago, SOXBLOX said:

Anyways, they have no hold on SpaceX's funding.

Originally Space Shuttle was to have liquid fuel boosters...

4 minutes ago, SOXBLOX said:

Does your city trash its buses after every use?

When rockets will begin doing same amount of flights like planes, let alone the buses...

And it's hard to see how a shroud can be worthy of a whole seaship travel, its fuel, and salaries.

[CatastrophicFailure]

17 minutes ago, kerbiloid said:

And it's hard to see how a shroud can be worthy of a whole seaship travel, its fuel, and salaries.

It’s not about saving money with the fairings, it’s about saving time. SpaceX’s launch cadence is incredible, and those fairing are a major choke point in that. Every set they can reuse, even at zero cost savings, is quicker than building new ones. 

36 minutes ago, kerbiloid said:

It's hard to overcomplicate more, and to create more potential crash points.

Solvable. Engineering. Problems. 

[SOXBLOX]

59 minutes ago, CatastrophicFailure said:

Solvable. Engineering. Problems. 

Exactly! We have to distinguish between physical impossibilities and engineering challenges.

[SOXBLOX]

6 hours ago, kerbiloid said:

It's hard to overcomplicate more, and to create more potential crash points.

I guess this kind of assertion begs the question, do you know a better way to access space? Like all things, Starship is a risk. Its promise is the fact that it's particularly high reward.

[kerbiloid]

1 hour ago, SOXBLOX said:

I guess this kind of assertion begs the question, do you know a better way to access space?

I guess, Boeing knows better than me.