Progress Undocking Clears Way for New Station Cargo Craft

Progress Undocking Clears Way for New Station Cargo Craft

09.07.05


An unpiloted Progress cargo craft was undocked from the International Space
Station at 6:26 a.m. EDT Wednesday, clearing the aft docking port of the
Zvezda Service Module for arrival of a new cargo carrier.

The old Progress, which had been at the Station since June 18, was
subsequently deorbited to burn in the Earth's atmosphere with its load of
Station trash.

The new craft is the 19th unpiloted Progress cargo vehicle to dock at the
International Space Station. It will be a breath of fresh air, in several
senses.

Among the cargo carrier's more than 2.6 tons of cargo is a new liquids unit
for the Russian Elektron oxygen generator. The unit has been out of
operation since late May.


The crew has relied on Solid Fuel Oxygen Generator (SFOG) "candles" and
oxygen from Progress and Station tanks to replenish the orbiting
laboratory's atmosphere. The Elektron uses water as a raw material, dividing
it into hydrogen, which is vented overboard, and oxygen.

Progress 19, scheduled to launch Thursday from the Baikonur Cosmodrome in
Kazakhstan, has been fitted with 14 extra tanks. They enable it to carry an
additional 132 pounds of oxygen and air, for a total of just over 242
pounds. Also aboard are 16 new SFOGs.

Total P19 cargo weight is just over 5,175 pounds. That includes 1,760 pounds
of propellant for attitude control thrusters, more than 52 gallons of water
and about 2,700 pounds of dry cargo.

That dry cargo consists of equipment and supplies, experiment hardware,
spare parts for the Russian Vozdukh carbon dioxide removal system and food.
That food is one reason a Progress arrival is a happy occasion, despite the
hard work involved in unloading and stowing cargo items.

Fresh food is especially welcome after months in orbit.

The Progress is similar in appearance and some design elements to the Soyuz
spacecraft, which brings three crewmembers to the Station, serves as a
lifeboat while they are there and returns them to Earth. The aft module, the
instrumentation and propulsion module, is nearly identical.

But the second of the three Progress sections is a refueling module, and the
third, uppermost as the Progress sits on the launch pad, is a cargo module.
On the Soyuz, the descent module, where the crew is seated on launch and
which returns them to Earth, is the middle module and the third is called
the orbital module.



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Jacques :-)

www.spacepatches.info