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No matter what
was said and written about Mir during its trouble
years at the end of the 1990s, this space station
will enter history books as a resounding success.
Yet, 15 years of Mir operation testify that despite
the fact that humans learned to survive in orbit for
months and years, space remains a very dangerous
place. Here is the log of the most perilous
situations, which Mir inhabitants had to go through
and important lessons they gave to cosmonauts and
designers of future spacecraft.
September 6, 1988: The Soyuz TM-5 landing
After rather uneventful seven-day visit to Mir, a
guest cosmonaut from Afghanistan Abdul Akhad Momand
boarded the Soyuz TM-5 spacecraft for a trip home,
accompanied by an experienced commander Vladimir
Lyakhov, returning home after a long-duration
mission to Mir. Immediately after undocking, a
combination of human errors caused the Soyuz to spin
around, while still in proximity of the station.
Fortunately, the commander was able to stabilize the
ship quickly and safely depart the station. Sometime
later, as planned, the Soyuz jettisoned its
habitation module in preparation for the deorbiting
maneuver. (Separating the module would allow to save
fuel for deorbiting maneuver).
However, 30 seconds before scheduled braking
maneuver, the orientation system onboard the
spacecraft failed causing a seven-minute delay in
the engine firing. When the engine did fire
automatically, Lyakhov immediately shot it down,
since he had no idea where the new reentry
trajectory would take the craft.
One orbit later, the crew made a second attempt to
deorbit their Soyuz. However, this time, the
automatic system confused by previous emergency
instructions from the ground, not only shot down the
engines, but also launched a countdown for the
separation of the propulsion module with all its
vital systems including braking engine itself. If
Laykhov did not manage to suppress the countdown,
the automatic system would separate the reentry
capsule from the propulsion module and most
certainly doom the crew.
After the ordeal, the Soyuz TM-5 and its crew
circled the Earth for 24 hours, without toilet and
water left in the jettisoned habitation module.
Another deorbiting attempt was made on September 7,
1988, when everything worked perfectly and the crew
landed safely.
The Soviet designers learned from the lesson: never
again the habitation module, with all its vital
systems, would be separated from the Soyuz until
deorbiting maneuver had been successfully completed.
1990: Soyuz TM-9 insulation problems
Soon after the launch toward Mir on February 11,
1990, the cosmonauts Anatoly Soloviev and Alexander
Balandin discovered that thermal protection sheets
on the reentry capsule of their Soyuz spacecraft
came loose. Fearing resulting failures in the
spacecraft sensors, ground control devised a plan to
fix the insulation back in place during an emergency
EVA, once the crew gets to Mir. The possibility of
sending a one-man rescue ship to pick Soloviev and
Balandin was also under consideration.
After watching instructional tapes on insulation
repairs, Soloviev and Balandin ventured outside the
station through the hatch of the Kvant-2 module on
July 17, 1990. After an exhaustive spacewalk and
their supply of oxygen running out the repair job
was mostly accomplished. However, when the
cosmonauts returned to the Kvant-2 they discovered
that the module's airlock hatch would not close.
Thanks to the module's ingenious design, the crew
was able to unpressurize the middle compartment of
the Kvant-2 and used it as an airlock to return into
the station.
During the next spacewalk on July 25, 1990, the crew
resumed its struggle with the hatch on Kvant-2 and
eventually succeeded with closing it properly and
repressurizing all compartments on the module.
In August 1990, the Soyuz TM-9 landed flawlessly,
while the damaged hatch of the Kvant-2 module was
eventually repaired as well. This experience gave
another lesson to designers: build your airlocks
with hatches opening inside the craft, so that
internal pressure would help to keep it tightly
closed. One wondering how this lesson was learned
should look at the docking compartment of the
International Space Station, which also serves as
the airlock for the Russian segment of the station.
Its EVA hatch opens inside.
March 21, 1991: Progress M-7 near miss
Following a first aborted attempt to dock, the
Progress M-7 cargo ship controlled from the ground,
tried again only to zoom within meters from the
station, narrowly avoiding the collision.
The rendezvous problems reoccur as Mir crew redocks
its Soyuz TM-11 spacecraft to the rear docking port
on Mir's Kvant-1 module. The problem is finally
traced to the Kurs rendezvous system onboard Mir,
which has one of its antennas missing.
January 14, 1994: Soyuz TM-17 collides with Mir
As the departing Russo-French crew conducts
overflight inspection of the station, their Soyuz
TM-17 spacecraft hits the Kristall module on Mir at
least twice.
Following the successful landing of the crew, the
ground processing teams discover a number of
"souvenirs" taken by the crew from the station,
which exceed the weight limit allowed onboard the
Soyuz during landing. The Russian investigation team
suggests that excessive weight onboard the craft not
only endangered the crew during landing, but it
could also contribute to the problems with the
attitude control system during the overflight of the
station and therefore make the collision with the
station more likely.
The moral of the story: the strict "packing up"
guidelines for the future station crews.
February 23, 1997: Fire onboard
During a routine ignition of an oxygen-generating
canister, cosmonaut Alexander Lazutkin suddenly
faces a flame going out of control. Before the crew
puts on gas masks and extinguishes the fire, a
multi-module complex, including the Soyuz
spacecraft, their only "lifeboat" is filled with
smoke. Fortunately, the station's life-support
system eventually "clears the air."
June 25, 1997: The collision
The same Russian crew including Vasiliy Tsibliev and
Alexander Lazutkin, which just several months ago
was battling flames on Mir, plus NASA astronaut
Michael Foale, found themselves in the middle of the
worst collision in space history. During a docking
test with the use of remote control onboard the
station, Tsibliev lost control of a tumbling cargo
ship. The vehicle collides with the station and
seconds later, the crew onboard Mir hears a hissing
sound of air escaping their vessel. Miraculously,
almost instantly, the crewmembers were able to
locate the air leak to Spektr module. After short
struggle to find cutting tools, they severed the
cables leading into the Spektr and safely sealed the
hatches.
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