Pirs docking compartment lifetime

I was looking for the ISS future assembly sequence, and got off track looking
at past missions. The Pirs assembly page at:
http://www.nasa.gov/mission_pages/st...ents/pirs.html

states:

The docking compartment's lifetime as part of the Station is five
years.

Since Pirs was docked to the space station on September 16, 2001 it would
appear that this lifetime has already expired.

I wonder why a module was designed with such a short lifetime? I've seen
nothing about it's life being extended, or it's disposal. So what do the ISS
experts on this group have to say about that?

Glen Overby
Twin Cities, MN

I am no expert, but I do recall that the original plan was to discard
Pirs within 5 years, to be replaced by Docking Compartment 2.




Glen Overby wrote:
I was looking for the ISS future assembly sequence, and got off track looking
at past missions. The Pirs assembly page at:
http://www.nasa.gov/mission_pages/st...ents/pirs.html

states:

The docking compartment's lifetime as part of the Station is five
years.

Since Pirs was docked to the space station on September 16, 2001 it would
appear that this lifetime has already expired.

I wonder why a module was designed with such a short lifetime? I've seen
nothing about it's life being extended, or it's disposal. So what do the ISS
experts on this group have to say about that?

Glen Overby
Twin Cities, MN

wrote in
oups.com:

Glen Overby wrote:
I was looking for the ISS future assembly sequence, and got off track
looking at past missions. The Pirs assembly page at:
http://www.nasa.gov/mission_pages/st...ements/pirs.ht
ml

states:

The docking compartment's lifetime as part of the Station is
five years.

Since Pirs was docked to the space station on September 16, 2001 it
would appear that this lifetime has already expired.

I wonder why a module was designed with such a short lifetime? I've
seen nothing about it's life being extended, or it's disposal. So
what do the ISS experts on this group have to say about that?

I am no expert, but I do recall that the original plan was to discard
Pirs within 5 years, to be replaced by Docking Compartment 2.

That's right. Pirs docked to the Zvezda nadir docking port as an interim
airlock/docking module until the Universal Docking Module would have been
launched. Then Docking Compartment 2 would have docked to the UDM.

In the current assembly sequence, the Russians plan to relocate Pirs to
Zvezda zenith to serve as the base for a truncated Science Power Platform.
The UDM has been replaced with FGB-2.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

Of course, FGB-2 will first dock with FGB Nadir, via probe and cone,
and then magically transfer over to Service Module nadir's hybrid port.


Jorge R. Frank wrote:
wrote in
oups.com:

Glen Overby wrote:
I was looking for the ISS future assembly sequence, and got off track
looking at past missions. The Pirs assembly page at:
http://www.nasa.gov/mission_pages/st...ements/pirs.ht
ml

states:

The docking compartment's lifetime as part of the Station is
five years.

Since Pirs was docked to the space station on September 16, 2001 it
would appear that this lifetime has already expired.

I wonder why a module was designed with such a short lifetime? I've
seen nothing about it's life being extended, or it's disposal. So
what do the ISS experts on this group have to say about that?

I am no expert, but I do recall that the original plan was to discard
Pirs within 5 years, to be replaced by Docking Compartment 2.

That's right. Pirs docked to the Zvezda nadir docking port as an interim
airlock/docking module until the Universal Docking Module would have been
launched. Then Docking Compartment 2 would have docked to the UDM.

In the current assembly sequence, the Russians plan to relocate Pirs to
Zvezda zenith to serve as the base for a truncated Science Power Platform.
The UDM has been replaced with FGB-2.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

wrote in
oups.com:

Of course, FGB-2 will first dock with FGB Nadir, via probe and cone,
and then magically transfer over to Service Module nadir's hybrid
port.

Or the Russians will replace FGB-2's probe and cone with a hybrid mechanism
before launch, just like FGB-1 had. No magic required.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

Huh?

You mean that the FGB-2 probe male docking adapter would be replaced
prior to launch with a hybrid male adapter? In that event, how would
FGB-2 dock with FGB-1? Remember that there is a firm requirement to
have a module docked at FGB nadir prior to the arrival of Node 3.



Jorge R. Frank wrote:
wrote in
oups.com:

Of course, FGB-2 will first dock with FGB Nadir, via probe and cone,
and then magically transfer over to Service Module nadir's hybrid
port.

Or the Russians will replace FGB-2's probe and cone with a hybrid mechanism
before launch, just like FGB-1 had. No magic required.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

wrote in
oups.com:

Huh?

You mean that the FGB-2 probe male docking adapter would be replaced
prior to launch with a hybrid male adapter?

Yes.

In that event, how would
FGB-2 dock with FGB-1?

It wouldn't - it would dock directly to Zvezda nadir.

Remember that there is a firm requirement to
have a module docked at FGB nadir prior to the arrival of Node 3.

There is a firm requirement to have three Soyuz/Progress/ATV docking ports,
but there are alternatives to FGB nadir for meeting that requirement.

Anyway, this is by no means a done deal, but it is something the Russians
are seriously looking at.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

Once Node 3 is installed, if the MLM (FGB-2) is at Service Module
nadir, how does Soyuz or Progress dock with FGB Nadir???


Jorge R. Frank wrote:
wrote in
oups.com:

Huh?

You mean that the FGB-2 probe male docking adapter would be replaced
prior to launch with a hybrid male adapter?

Yes.

In that event, how would
FGB-2 dock with FGB-1?

It wouldn't - it would dock directly to Zvezda nadir.

Remember that there is a firm requirement to
have a module docked at FGB nadir prior to the arrival of Node 3.

There is a firm requirement to have three Soyuz/Progress/ATV docking ports,
but there are alternatives to FGB nadir for meeting that requirement.

Anyway, this is by no means a done deal, but it is something the Russians
are seriously looking at.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.

wrote in
oups.com:

Jorge R. Frank wrote:
wrote in
oups.com:

Huh?

You mean that the FGB-2 probe male docking adapter would be
replaced prior to launch with a hybrid male adapter?

Yes.

In that event, how would
FGB-2 dock with FGB-1?

It wouldn't - it would dock directly to Zvezda nadir.

Remember that there is a firm requirement to
have a module docked at FGB nadir prior to the arrival of Node 3.

There is a firm requirement to have three Soyuz/Progress/ATV docking
ports, but there are alternatives to FGB nadir for meeting that
requirement.

Once Node 3 is installed, if the MLM (FGB-2) is at Service Module
nadir, how does Soyuz or Progress dock with FGB Nadir???

They wouldn't, under this hypothetical assembly option. An additional
docking port would be required, either added to the FGB-2 or as a separate
docking module.

--
JRF

Reply-to address spam-proofed - to reply by E-mail,
check "Organization" (I am not assimilated) and
think one step ahead of IBM.