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Russian Launch and Mission Thread


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22 minutes ago, kerbiloid said:

Btw thanks to this flight SU/RU has surpassed US in suborbital flights in 2 nominations.

Now
1) both have 2 suborbital flights: 2 Mercuries vs 2 Soyuzes 
2) both have 3 suborbital people: 2 in Mercuries + 1 in Soyuz vs 2+1 in Soyuzes

but
1) SU/RU launched twice more people into suborbit (1+1 vs 2+2)
2) SU/RU did it with 2-seat ships

Cool comparison, but based on math based on the next few frames of simulation shown, this flight only had an apogee of 80-90 kilometers and therefore is not a suborbital flight.

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55 minutes ago, CatastrophicFailure said:

It was the first couple of Vostoks, apparently, but similar concept.

Extremely dissimilar design. Soyuz reentry capsules are like the housing for headlights; Vostoks are perfectly spherical. One has an infinite axis of symmetry and the other has a limited axis of symmetry (only one, in fact).

Again, you don't want them to reenter hatch first.

55 minutes ago, CatastrophicFailure said:

during all this the Station has never been close to an emergency situation that would require anything so extreme.

Keeping the station unmanned is actually less extreme than pushing the limits of what the rockets or ferry spacecraft can do.

Edited by YNM
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41 minutes ago, YNM said:

you don't want them to reenter hatch first.

Afaik that happened only once, with Soyuz-5, in the early days of Soyuz flights, with its very first version several times redesigned since then.

And it was re-entering with head down because the service module hadn't separated properly.

Then it had happily turned with bottom down.

 

Also peroxide doesn't disappear magically at once.
It just gets not guaranteed to be enough to keep the whole descent gliding.

Edited by kerbiloid
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45 minutes ago, YNM said:

Again, you don't want them to reenter hatch first.

You’re missing the point, my friend. :wink: Which is, they won’t enter hatch first. 

 

9 minutes ago, kerbiloid said:

Afaik that happened only once, with Soyuz-5, in the early days of Soyuz flights, with its very first version several times redesigned since then.

And it was re-entering with head down because the service module hadn't separated properly.

 Then it had happily turned with bottom down.

That’s the one I was thinking of, thanks. 

Yes, as soon as the service module broke free, the entry capsule naturally righted itself. 

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10 minutes ago, YNM said:

And that still messed up the parachutes ?

So, you should keep your peroxide for the capsule stabilization on the parachute system engaging.

The only reason why it was overturned was the service module which hadn't separated, so it was jettisoned by heat sensors on aerobraking.

P.S.
Could Mercuries into gliding descent? Vostoks? Voskhods?

Edited by kerbiloid
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22 minutes ago, razark said:

And who gave them the authority to decide, rather than the USAF?

And who gave the USAF any authority?

I hereby proclaim "Space" to start at an altitude of four miles above sea level. If you have flown on an airliner, congratulations, you are an astronaut!

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17 minutes ago, Ultimate Steve said:

And who gave the USAF any authority?
...

So, the point stands, that it really is an arbitrary definition, and "space" depends on who you accept as the authority?

 

Edit:
The best definition I've heard is "the altitude at which the speed a vehicle achieves enough aerodynamic lift to stay aloft exceeds the orbital velocity".  That seems like a reasonable definition, based on physics, and not an arbitrary altitude.  However, I've always seen that attached to the 100 km altitude, and I'm not entirely sure why.

Edited by razark
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18 minutes ago, razark said:

So, the point stands, that it really is an arbitrary definition, and "space" depends on who you accept as the authority?

Not too arbitrary TBH. 100 km is (about the) Karman line, where any lift-supported flights will need to go at or faster than the circular orbital speed.

And it's also not too arbitrary because below that you'll already reenter and before it you just started heating up.

idk, I'd say that it's a matter of conveniency. 50 mi is a round number, same as 100 km.

Edited by YNM
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7 minutes ago, YNM said:

... where any lift-supported flights will need to go at or faster than the circular orbital speed.

But why is that 100 km?  That seems a bit too convenient to me, that the altitude at which lift becomes meaningless is a nice round number. 

Besides, isn't lift a result of vehicle design?  Does that mean a rock is in space at 1 km?  (See my previous response.  It's a good definition, since it's based on physics and not just "magic numbers".  I'm just not sure why it is what it is.  Is this some theoretical maximum at which lift for any vehicle requires a higher speed?  What if someone demonstrated a vehicle that did provide enough lift at 110 km?  Would the definition change?)

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Just now, razark said:

But why is that 100 km?  That seems a bit too convenient to me, that the altitude at which lift becomes meaningless is a nice round number. 

Besides, isn't lift a result of vehicle design?  Does that mean a rock is in space at 1 km?  (See my previous response.  It's a good definition, since it's based on physics and not just "magic numbers".  I'm just not sure why it is what it is.  Is this some theoretical maximum at which lift for any vehicle requires a higher speed?  What if someone demonstrated a vehicle that did provide enough lift at 110 km?  Would the definition change?)

I think they made a generalized assumption based on an "average" aircraft and it came out close so they rounded, but I'm not sure.

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1 hour ago, razark said:

But why is that 100 km?  That seems a bit too convenient to me, that the altitude at which lift becomes meaningless is a nice round number. 

It isn't.

You're the one who works in the world's largest aeronatical and astronautical reaearch organization, you can definitely just plug numbers into this equation :

660945dedd89c630807415c89ac15f901a1cdfc3

And see where the line is actually.

Edited by YNM
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3 minutes ago, YNM said:

You're the one who works in the world's largest aeronatical and astronautical reaearch organization

Yeah, but I'm in IT, not one of the "fun" areas. :(

 

3 minutes ago, YNM said:

you can definitely just plug numbers into this equation

I'll try and do so tomorrow, once the whiskey wears off.  Is there a source that defines the variables?

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50 minutes ago, razark said:

Is there a source that defines the variables?

v0 is circular orbital speed (sqrt(GM/(H+Rearth)), you can get the density (ρ) from one of the standard density models (I'm sure your colleagues has them), g is the gravitational acceleration at the height (GM/((H+Rearth)^2)), S and CL is the wing area and lift coefficient (idk, ask one of your colleagues, maybe one of their high-altitude gliders), m is the aircraft/spacecraft mass. L is the lift force, which is why it has to be equal to m*g (weight of the craft).

50 minutes ago, razark said:

Yeah, but I'm in IT, not one of the "fun" areas. :(

And here I am trying to learn to ensure everything is pertinent to the ground and not sinking or collapsing into it...

Edited by YNM
edited as requested by post below.
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3 minutes ago, YNM said:

I'm sure your colleagues has them

My father is the engineer.  Mostly my colleague complains how much he hates Java and Adobe. 
I tell him at least he's not taking a class on assembly language.

L and p I'm not seeing listed.  (I minored in geology, not physics.  There's a lot I would change if I could go through school again.)

 

Anyway, I'm willing to accept that there is a reason for the definition, even if I don't understand it right now.

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The short answer is that it isn't exactly 100 km, but for reasonable values in that equation it is so close to 100 km most people accept that (there is still some debate). It does vary a bit based on atmospheric conditions also. This is one of those values that isn't completely arbitrary, but there are inherent assumptions and variability in any value you pick so we went with a nice round number which is very close to what you would get with reasonable assumptions and variations.

12 minutes ago, razark said:

My father is the engineer.  Mostly my colleague complains how much he hates Java and Adobe. 
I tell him at least he's not taking a class on assembly language.

L and p I'm not seeing listed.  (I minored in geology, not physics.  There's a lot I would change if I could go through school again.)

 

Anyway, I'm willing to accept that there is a reason for the definition, even if I don't understand it right now.

Pulling from wikipedia:

L is the lift force
ρ is the air density
v is the aircraft's speed relative to the air
S is the aircraft's wing area,
CL is the lift coefficient.[7]
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On 10/15/2018 at 7:32 PM, Ho Lam Kerman said:

Good point, @AVaughan. I go look up the Soyuz blueprints to see if I can find anything useful.

Edit: Could this be a feeling port or whatever, circled in grey? I'll try find more detailed blueprints.

lFEe89E.jpg

Those are orientation sensors. There's a Sun sensor and an infrared sensor on the service module as an alternative to looking through the Vzor periscope.

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The atmo-space border just cannot have any exact value like 100 km, because it varies with latitude, it has local heterogenities, and it varies with solar activity and other natural factors.
So, "100 km", "50 mi" or any other number are arbitrary.

So, maybe from aviation pov (FAI, X-15, etc) it's not a space, but R-7 as well as Redstone are ICBM, and by USAF definition it's da space!

They should have two border definitions: one for horizontal flight of an aerial craft (let FAI define it), another one for orbital flight of non-aerial craft (rocketeers know better).
The 50..90 km "jump zone" is between. Planes can't be flying there as well as satellites. 

Edited by kerbiloid
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