It's Official: Russia cuts off US access to Space.

In article ,
says...

"Jeff Findley" wrote in message
...

In article ,
says...

http://www.telegraph.co.uk/news/worl...sanctions.html

http://www.telegraph.co.uk/news/worldnews/europe/russia/10828964/Russia-to-ban-US-from-using-Space-Station-over-Ukraine-sanctions.html

The seeds came when Space Station Freedom was cancelled in
favor of the ISS. (The US paid a lot of the cost of building
it, including spotting a lot of Russia's share of the cost.)

It would be very nice if we had ARES right now!

No, it wouldn't. Ares is a launch vehicle. The US has plenty of launch
vehicles which can deliver payloads to ISS. What the US lacks are ISS
module(s) to replace the Russian modules. Specifically, the US lacks a
propulsion module (and other bits of functionality).


I wouldn't worry too much about that.

We can resurrect http://en.wikipedia.org/wiki/ISS_Propulsion_Module in the
worst case.

And redesign it for launch on an expendable, since it was originally
designed to be carried to ISS in the shuttle's payload bay. This would
be non-trivial since launching something into orbit is the *easy* part.
Rendezvous and berthing/docking with ISS is the *hard* part. The US
currently only has Cygnus and Dragon doing that today. I'm not sure
either is well suited for delivering a fairly massive module like the
ISS Propulsion Module.

Cygnus would be a better bet if you ditched the pressurized module and
replaced it with the propulsion module. But that would likely require a
bigger launch vehicle than it currently uses. Anything is possible,
given enough time and money.

We can also perhaps rely on modified Falcon and ATV in the meantime.

You mean Dragon. ATV would mean building more of them, which Europe
might not be willing to do since that would cost quite a bit of money to
restart ATV "production".

On the other hand, my understanding is the Russian modules are tight on
power w/o the US.

Power and attitude control with the CMGs.

And on the gripping hand, Russia loves its money. So we'll see how long
this all lasts.

I'm thinking this whole thing is yet another play by the Russians for
more cash. With commercial cargo in full swing and commercial crew on
the way, the cash payments for Progress and Soyuz flights will be coming
to an end.

Wonder if the dorks in DC will get it together (good luck) and
build it now? Get on your horses, DC! Manned space flight is
the outreach - People watch NASA for Buck Rogers, you can't have
him grounded and hold a crowd!

SLS, Ares V's congressionally mandated replacement, isn't doing terribly
well. Costs are high and schedules are long. If you're looking for SLS
to "save" ISS by 2020, I'd start looking elsewhere.

Hello Mr. Musk, we'd like to talk about some bulk purchases....

Tell that to DOD who seem to be giving SpaceX grief over certifying
Falcon 9 v1.1 for EELV class launches, instead giving ULA a huge "block
buy" of EELV cores using a non-compete contract. This would appear to
be a no-no according to government procurement rules with Falcon 9 v1.1
having made several successful flights.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

On Wednesday, May 14, 2014 5:20:25 PM UTC-4, wrote:
while back could the Russians deny us access and take over the ISS. I was told
no.

Not by me.

Apparently they're doing just that. And we have no recourse? That's just
great.

Well not so fast. As I understand it the Russians are dependent upon NASA ISS mission control for supplying power to their modules. At least until they can fly their own modules that would make the Russian modules self-sufficient in power.

We, US/NASA are dependent upon the Russian modules for navigation/station-keeping. And, unlike our Russian friends, no plans on the drawing boards for replacing those modules.

But this kind of back-and-forth bickering is ultimately pointless. In this case I believe possession (occupation) is 9/10ths of the law.

http://files.abovetopsecret.com/file...ps505cef1c.jpg

Dave

Maybe the US might want to consider throwing some bucks at Bigelow and SpaceX?

Naaaah...

In article om,
says...

On 14-05-15 07:46, Jeff Findley wrote:

"Counter weights" makes no sense. This is microgravity, remember? The
attitude engines used to desaturate the CMGs are quite necessary.

Would CMGs really be effective if Z1/node1 were the aft end of the
station ? (aka: drop russian segment)

Don't gryos work better when they are nearer to centre of mass as
opposed to being at one end ?

CMGs can only import a torque on ISS, not a force (i.e. you can't change
your orbit with a CMG). If you assume ISS is a rigid body, it really
does not matter where on ISS the torque is applied. This is level 200
mechanics.

Since ISS is not truly rigid, any issues caused by CMG torque would need
to be analyzed in detail. Software on ISS might need to be changed to
deal with any issues found (e.g. the limits on the magnitude of torque
which can be applied might need to be updated). I'll take a look at my
500 level Spacecraft Attitude Dynamics book when I get to work to see
what it has to say on the topic. It's been a while since I've cracked
open that particular book.

Considering they have yet to hand over the "control codes" for the
Russian built parts of ISS that the US paid *cash* for and claims it
owns, I seriously doubt that would happen.

If Russia abandons its segment, the USA simply needs to cut the antennas
to Russia and reverse engineer the russian segment. Remember that the
USA also has data links to command and control to the russian segment.

Good luck with that (reverse engineering hardware and software
remotely).

If an ATV is docked, then surely the french can send commands to
the ATV to get its thursters to fire, right ?

Possible, but the "production line" for ATV isn't open anymore. There
is only one more ATV to be launched to ISS and there aren't any spares
I'm aware of. ESA would have to fun construction of new ATVs.

Russia, on the other hand, has been producing Soyuz and Progress for
decades, so building new copies of them isn't as expensive.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer

In article om,
says...

On 14-05-15 07:55, Jeff Findley wrote:

I'm thinking this whole thing is yet another play by the Russians for
more cash. With commercial cargo in full swing and commercial crew on
the way, the cash payments for Progress and Soyuz flights will be coming
to an end.

If the Russians can send mass at lower cost than Space-X and Orbital
Sciences, they could still keep progress in business (forgetting current
diplomatic problems)

Right now no one on the planet can touch SpaceX in terms of cost. I
suppose Russia might try to undercut SpaceX, but I doubt Congress would
vote to send more money to Russia instead of spending it in the US.
SpaceX and Orbital have both proven the US can be competitive on cost in
the area of Commercial Cargo. Commercial Crew isn't here yet, but I'd
bet Congress might be in the mood to spend more money on it than send
more money to Russia.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer