Conference 7.286::space

All right!  Here's one where we have a chance of seeing the end stages of the
main engine burn and the ET Sep from New England!

Burns

    
    Launch March 21, 1996 at 3:34 a.m. EST (ESTIMATED)
    Launch Window 6 min.
    
    Mission Objectives:
    
    The primary mission objective will be the third docking between the
    Space Shuttle Atlantis and the Russian Space Station Mir. It will
    include a crew transfer, an extravehicular activity (EVA), logistics
    operations and scientific research. 
    
    Rendezvous and docking with Mir is scheduled to occur on flight day
    three using the same approach as previously used during STS-74. Docking
    will occur between the Orbiter Docking System in the forward area of
    Atlantis' payload bay and the Docking Module installed during STS-74 on
    Mir's Kristall module docking port. 
    
    The mission will also feature a SPACEHAB module, middeck experiments, a
    Get Away Special (GAS) canister and a 6-hour EVA. Over 1,900 pounds
    (862 kilograms) of equipment are being transfered from Atlantis to Mir
    including a gyrodyne, transformer, batteries, food, water, film and
    clothing. 
    
    Planned Experiments include the Mir Electric Field Characterization
    (MEFC) experiment, numerious European Space Agency's (ESA) Biorack life
    sciences experiments, the Queen's University Experiment in Liquid
    Diffusion (QUELD) experiment, the Optizone Liquid Phase Sintering
    Experiment (OLIPSE) and a Naval Research Laboratory (NRL) Get Away
    Special (GAS) payload that will measure low-energy particle radiation
    in the inner magnetosphere. 
    
    Mission Specialists Godwin and Clifford are scheduled to perform a
    six-hour spacewalk on flight day six. They will attach four
    experiments, known collectively as the Mir Environmental Effects
    Payload MEEP, onto handrails located on the Mir Docking Module. These
    experiments include the Polished Plate Micrometeoriod Debris (PPMD)
    experiment, the Orbital Debris Collector (ODC) experiment, and the
    Passive Optical Samples (POSA) I and II experiments. 
    
    

Hopefully this one will be as visible from GMA as the last nighttime MIR
rendezvous was!

Burns

    Looks like the Florida weather has delayed launch for 24 hours,
    due to high winds which would have precluded an abort return to
    Kennedy if needed.
    As far as weather for us in the GMA to see the launch, it isn't looking
    promising for tomorrow morning. :(
    
    Bob

The funny thing is that it actually cleared up for a few hours last night.  I
don't know about 3AM, though.

Also, tonight, the launch will be a bit earlier than it would have been last
night.  In the 2AM area, I think.

Burns

Actually, I double checked.  The time was given in Central time, rather than
Eastern.  It's only a few minutes earlier (3:13 EST)

Burns

    Heard on the 6am news this morning:
    
    Atlantis launched OK this morning but they're having trouble with one
    of the APUs -- can someone amplify/clarify?
    
    Help!
    
    -Eric-who's-stuck-in-a-clean-room- :^(

Apparently there was a hydraulic leak in one of the APU circuits.  They claim it
is not a problem.  Of course the APUs don't run again until landing, so I assume
they don't believe it is any more dangerous to stay up than to come down.

Burns

Anyone along the eastern seaboard get up to try to see it?  All evening there
were occasional holes overhead in Nashua, but clouds to the south, so I did not
get up.

Burns

    Well as you said a few notes back Burns, it was clear earlier in
    the night. Before I hit the sheets, I took a peek, saw it was clear,
    stepped out on the deck & checked out Comet Hyakutake. It's really
    getting impressive. Through a pair of 7X35 binoc's one can see some
    structure of a tail using averted vision.
    Back to the launch. I woke again right about at 3:00am looked out the
    window and couldn't see a star, but saw a lot of cloud glow from
    lights below. :(
    Turned on the tv, watched the launch (had the vcr already programmed
    to tape NASA Select), and went back to sleep after it cleared MECO.
    When I awoke at 6:00am or so, there was the trailing end of the post 
    launch press conf with the discussion of the leaking APU. Something 
    was mentioned about having lost 20% of the fuel for that particular 
    APU. I don't remember too much else of what was said. 
    While listening to NPR before leaving the house, it was mentioned
    that there should be no affect on the docking to MIR, but it was
    mentioned that after they undock from MIR, NASA would address the
    issue about shortening the flight and landing early.
    
    Bob

    The APUs are powered by hydrazine, not something I would want leaking
    anywhere in any vehicle I was flying in.  Many years back in the pre-
    Challenger days, there was a shuttle landing where one of the APUs had
    a leak and a fire had been started.  Given that the APUs are located
    aft near the verticle tail, there was no danger to the crew (they were
    down, after all).  My guess is that they won't run this offending APU
    for decent.

    Well,I guess they've isolated the "leak" to being a hydraulic leak 
    associated with one of the SSME gimbals.  They close off that circuit
    during entry and landing so they feel that there is no further concern.
    I wonder if this problem solving was done by telemetery or by manual
    testing by isolating various systems?  From what I gather, the APUs
    have not been restarted, hence no pressure (unless residual pressure
    from launch) to test the systems.

    The APU's have a "high pressure" mode and a "low pressure" mode.
    It's the high pressure mode that the hydraulic leak was observed
    using pressure sensors which are monitored and sent back to the ground
    by telemetry. At the post launch conference it was mentioned that when 
    the APU's are first started they are running at somewhere around
    300psi. After they warm up and the shuttle has left the pad, the
    pressure builds up into the 3000psi range. It wasn't until the shuttle
    had left the pad that they apparently observed the leak in APU #3
    (which must have shown up as a drop in what would have been a nominal
    pressure range). When they got to orbit, the APU's are shut off, but
    apparently maintain some residual pressure of around 80psi.
    The aft compartment where the APU's are located has vent doors which
    are normally open to the cold of space. It was mentioned that they
    felt that at the cold temperatures of orbit, the hydraulic fluid
    would be quite viscous and sticky and as such wouldn't really go
    anywhere. It was mentioned some time Saturday morning that one of
    the precautions they took was to close the aft compartment doors
    prior to the rendezvous. 
    There was a discussion in some interview where it was mentioned that
    the folks on the ground were discussing their options on how
    to handle APU #3 when initiating the de-orbit. The options (that 
    haven't been finalized yet), are things like delaying the start of
    APU #3 until late in the re-entry, or starting it with the others,
    but run it at low pressure until needed later in the descent.
    They estimate that they have about 45 minutes of hydraulic fluid
    left for APU #3, and so if they delay the start of it, They can land
    with 3 APU's. So apparently there isn't any huge concern by the
    engineers working the logistics & procedures of the restart of the
    APU's come de-orbit time.
    
    Bob

So Bob, are you of the opinion that they can't close off the pressure to the
SSME gimbal actuators where the leak apparently is?  I would think they would
not need that on the way down!

Burns

    I didn't see/hear any discussion of whether they had actually
    pinned down the whereabouts of the leak to the area of the
    SSME gimbal actuators Burns. I did hear Bob Castle say that they
    wouldn't be able to ascertain where the leak "actually" is until
    they get the orbiter back on the ground and get someone inside
    the aft compartment to take a look. So I don't know what the
    source is for the SSME gimbal actuators on APU #3 conjecture is
    coming from. The thing here is that all three APU's are used for 
    control of other things (wing flaps, tail rudder etc), in addition
    to the main engine gimbal actuators. So when Castle was talking of
    late start of  APU #3, he mentioned that the only purpose of the
    APU's in the de-orbit landing phase was for the air controls once
    the shuttle gets low enough to use air surfaces to control instead
    of using thrusters. So, he said that the main thing to remember is
    that APU #3 won't start leaking until it is in its highest pressure
    mode. 
    I think the hint here (which wasn't specifically mentioned by Bob Castle), 
    is that perhaps the absence of the need of the APU's to power the SSME 
    gimbals on the way down maybe means that the APU's (most specifically #3), 
    don't have to operate with as high a pressure range as they do as at 
    launch. This last sentence is my guess though not based on on any
    thing I saw or heard from the NASA folks. It would seem to make sense
    that not needing the APU's for the additional purpose of powering
    the SSME gimbal actuators on de-orbit  means that they maybe don't
    expect as high a range of pressure. So I think what they really
    must have intended is that not needing the hydraulic path for the
    gimbals will result in a lower overall pressure on the high side of
    the feed lines, but still enough to operate the tail and wing controls.
    I'm rambling... :-)
    
    Bob

    I was watching some of my vcr replay of the space walk last night,
    and as I was watch one part where both astronauts were floating near
    the orange MIR docking adapter, with part of the shuttle in view,
    with the blue earth in the background, I couldn't help but hear
    in my mind, strains of "Also Sprach Zarathustra" or "The Blue Danube".
    As many other space walks as I've watched in recent years, this one
    seemed to be significantly different. I can't put my finger on it!
    
    Bob

I just saw in the Shuttle status report that

1) Telemetry indicates that one of the redundant igniters on SSME #2 may not
have fired and

2) Atlantis will be coming back a day early (Saturday) due to expected KSC
weather conditions.

Burns

STS-76 Mission Control Center
Status Report # 2

Friday, March 22, 1996, 5:30 p.m. CST

Closing on the Russian Space Station Mir at a rate of 661 nautical
miles per orbit, the STS-76 crew will perform several rendezvous burns
today as the third Shuttle docking mission proceeds as planned.

This afternoon, the Mission Management Team met in Houston to discuss
a leak seen in one of the hydraulic systems during the ascent portion
of the flight. After an examination of the data, engineers concluded
that the leak began as the high pressure hydraulic fluid system pumps
were started shortly before launch. Data showed a leak rate of about 1
percent of the system's total reservoir per minute leading flight
controllers to believe that about 20 percent of the reservoir leaked
from the system.

The leak stopped when the system was shut down after ascent, and no
further leakage has been detected.  Since the leak only appears while
the system is operating, mission managers are confident that the
system will remain stable on orbit, and that there is no reason to
change the duration of the mission.

Controllers will continue to monitor the system for any changes in its
status.

Today, crew members will configure the SpaceHab module for its
on-orbit operations, check out the spacesuits that will be used by
Mission Specialists Rich Clifford and Linda Godwin later in the
flight, and test the equipment that will be used for the rendezvous
operations.

The crew began its day today at 3:13 p.m. Central with the song
"Anywhere Is" by Enya. Atlantis, making its 16th flight, is performing
well as it circles the Earth in a 159 by 127 n.m. orbit.

###



    

STS-76 Mission Control Center
Status Report # 3

Saturday, March 23, 1996 5:00 a.m. CST

STS-76 Commander Kevin Chilton and Pilot Rick Searfoss fired Atlantis'
orbital maneuvering system jets just before 3:30 a.m. today, refining
its path for this evening's rendezvous with the Mir Space Station.

This morning's burn slowed the rate at which Atlantis is closing on
Mir, and raised the high point of its orbit to 210 nautical miles in
anticipation of the terminal initiation burn that will position
Atlantis to intercept the space station. Currently Atlantis trails Mir
at a distance of about 3,000 nautical miles, closing the distance by
about 400 nautical miles every 90 minutes.

Throughout the night and into the early morning hours, the six
astronauts prepared for their docking with Mir, checking out the radio
communications equipment they will use during their approach. Mission
Specialists Linda Godwin and Rich Clifford also checked out the space
suits they will wear during Wednesday's planned six-hour EVA. The
suits and hardware have been temporarily stowed in Atlantis' airlock.

Chilton, Searfoss and Mission Specialist Shannon Lucid also spent time
this morning discussing the progress of their mission and Lucid's
planned stay on the Mir Space Station with NBC's Nightside
program. Lucid told Nightside host Tom Miller that she believed her
four-month stay on Mir "will be a great adventure."

The astronauts will begin a 7-hour sleep period at 7:13 a.m. central
time today before waking to begin final rendezvous and docking
activities. About one hour after waking up, Chilton and Searfoss will
fire Atlantis' maneuvering system engines in the final phasing burn
designed to further slow Atlantis' closing rate to 34 nautical miles
per orbit. One orbit later, Atlantis will be eight miles away from
Mir, in position for the terminal initiation burn that allows Atlantis
to intercept the Russian space station.

Chilton will initiate the TI burn at 5:52 p.m. central time, moving
Atlantis along a precise course to meet up with Mir. Atlantis will
stationkeep at a distance of 170 feet from Mir while flight
controllers in Houston and Moscow confer before giving a final "go"
for docking operations. Docking is targeted for 8:34 p.m. today.

All systems are continuing to perform well as Atlantis makes its 16th
journey into space.

###

    

STS-76 Mission Control Center
Status Report # 4

Sunday, March 24, 1996 1 a.m. CST

The JSC Newsroom will be open until 11 AM Central time Sunday before
closing until 2 AM Monday.

The following is the latest status report on the STS-76 mission:

Following a flawless rendezvous, Atlantis successfully docked to the
Russian Mir space station as Commander Kevin Chilton gently guided
Atlantis to a linkup at 8:34 PM Central time Saturday night.

A little less than two hours later, Mission Specialist Rich Clifford
completed safing and pressurizing Atlantis' docking vestibule and the
hatches were opened between the two spacecraft as Atlantis' crew was
greeted by Mir 21 Commander Yuri Onufrienko and Flight Engineer Yuri
Usachev.  Shortly after the hatch opening and initial greetings, the
shuttle crew moved into the Mir and astronaut Shannon Lucid officially
became the third member of the Mir-21 crew, embarking on a 4 1/2 month
stay in space to inaugurate a permanent U.S. presence in space on Mir
for the next two years. Lucid will be replaced by astronaut John Blaha
in August. Onufrienko and Usachev were launched on a Soyuz rocket to
the Mir on February 21st. They'll return to Earth in July after a
replacement crew of Russian cosmonauts and a French researcher joins
Lucid aboard the Mir.

As is traditional, the crews exchanged gifts during a short welcoming
ceremony in the Mir Core module, with the Mir crew giving Atlantis'
astronauts a variety of placards and memorabilia. Atlantis' crew gave
the cosmonauts commemorative shirts, chocolate Easter bunnies and two
books, including autographed copies of Apollo 13 Commander Jim
Lovell's "Lost Moon," on which the movie "Apollo 13" was
based. Chilton described the rendezvous, docking and initial moments
on the Mir as "unreal."

Following safety briefings for both crews on each other's respective
spacecraft, the astronauts and cosmonauts began transferring more than
a ton of water, Russian supplies, science equipment and other gear
from the shuttle to Mir. The transfer of equipment will continue
through much of the five days Atlantis is docked with the Mir.

Early Wednesday morning, while Atlantis is still docked to the Mir,
Clifford and Mission Specialist Linda Godwin will perform a six-hour
spacewalk outside Atlantis to affix four experiment packages to the
exterior of the Mir docking module.

The 230-ton Atlantis-Mir complex is orbiting the Earth every 90
minutes at an altitude of about 240 statute miles with all systems on
both craft operating normally.


    

STS-76 Mission Control Center
Status Report # 5

Sunday, March 24, 1996 11 a.m. CST

The Johnson Space Center Newsroom closed at 11 a.m. Sunday and will
reopen at 2 a.m.  CST Monday.

A long-term, continuous U.S. presence on Russia's Mir space station
was inaugurated early Sunday with the transfer of astronaut Shannon
Lucid to the Mir 21 crew.  The two spacecraft linked up in orbit at
8:34 p.m. CST Saturday for five days of joint operations.

Lucid is embarking on a 4 1/2 month stay in space, joining Mir 21
Commander Yuri Onufrienko and Flight Engineer Yuri Usachev.  Lucid is
the second U.S. astronaut to make an extended visit to Mir as part of
Phase 1 of the International Space Station Program.

The point of her transfer to the Mir crew occurred when the seat liner
she would use in the event of a return to Earth in the Soyuz capsule
was moved to the Mir.  Official assignment of Lucid to the Mir 21 crew
came at 7:30 a.m. central time today after Flight Director Bill Reeves
in Houston and Nikolai Nikiforov in Mission Control, Moscow, gave a
joint 'go' statement.

The astronauts and cosmonauts have begun transferring more than a ton
of water, Russian supplies, science equipment and other gear from the
shuttle to Mir. The transfer of equipment will continue through much
of the five days Atlantis is docked with the Mir.

The crew is now asleep, having begun a 10-hour sleep period at 8:43
a.m. central time today.  Astronauts will wake at 6:43 p.m. to begin
Flight Day 4.

Early Wednesday morning, while Atlantis is still docked to the Mir,
astronauts Rich Clifford and Linda Godwin will perform a six-hour
spacewalk outside Atlantis to attach four experiment packages to the
exterior of the Mir docking module.

The Shuttle and its now five person crew is expected to return to
Earth March 31 with a 6:03 a.m. CST landing at Kennedy Space Center,
Florida.

The 230-ton Atlantis-Mir complex is orbiting the Earth every 90
minutes at an altitude of about 240 statute miles with systems on both
craft operating normally.


    

STS-76 Mission Control Center
Status Report # 6

Monday, March 25, 1996, 7 a.m. CST

Transfer and resupply activities on board the joined Atlantis/Mir
spacecraft continue on or ahead of schedule as the eight astronauts
and cosmonauts work smoothly through their timeline.

Throughout the night and early morning hours, the crews moved between
the two vehicles transferring water, logistical supplies and hardware.
Mission Specialist Linda Godwin also continued her work with the
European Space Agency Biorack which contains 11 separate scientific
investigations.

Just before 2:30 a.m. central time today, Pilot Rick Searfoss narrated
a videotaped tour of the Mir complex which will be home to Shannon
Lucid and her Mir 21 crew mates -- Commander Yuri Onufrienko and Yuri
Usachev -- for the next few months.  Godwin and Mission Specialist Ron
Sega then provided a video update of their work with the Biorack
investigations and showed some of the transfer items currently stowed
in the SpaceHab module.

Shortly after 8 a.m., Atlantis Commander Kevin Chilton, Onufrienko and
Lucid will talk with NASA Administrator Daniel Goldin in Washington,
D.C.  Goldin is expected to congratulate the crew on the successful
docking of the two spacecraft.

The Atlantis crew will begin an eight-hour sleep period at 10:43
a.m. today, waking up at 6:43 p.m.

The Shuttle and its now five-person crew is expected to return to
Earth March 31 with a 6:03 a.m. CST landing at Kennedy Space Center,
Florida.

The 230-ton Atlantis-Mir complex is orbiting the Earth every 90
minutes at an altitude of about 240 statute miles with systems on both
spacecraft operating normally.


    

STS-76 Mission Control Center
Status Report # 7

Monday, March 25, 1996, 5 p.m. CST

The Johnson Space Center Newsroom closed at 5 p.m. CDT Monday and will
reopen at 12:30 a.m. Tuesday in preparation for the Joint Crew
In-Flight Press conference scheduled for just before 2 a.m.

Astronauts aboard Space Shuttle Atlantis were due to awaken at 6:43
p.m. CST to begin flight day five of the 76th shuttle mission.

Coming up late Monday and early Tuesday are continued transfer of
water, supplies and experiment hardware to Mir and preparations
leading up to Wednesday mornings spacewalk.

In the previous flight day, transfer and resupply activities on board
the joined Atlantis/Mir spacecraft continued on or ahead of schedule
as the eight astronauts and cosmonauts worked smoothly through their
timeline.

Throughout the night and early morning hours, the crews moved between
the two vehicles transferring water, logistical supplies and hardware.
Mission Specialist Linda Godwin also continued her work with the
European Space Agency Biorack which contains 11 separate scientific
investigations.

Just before 2:30 a.m. central time Monday, Pilot Rick Searfoss
narrated a videotaped tour of the Mir complex which will be home to
Shannon Lucid and her Mir 21 crew mates -- Commander Yuri Onufrienko
and Yuri Usachev -- for the next few months.  Godwin and Mission
Specialist Ron Sega then provided a video update of their work with
the Biorack investigations and showed some of the transfer items
currently stowed in the SpaceHab module.

Shortly after 8 a.m., Atlantis Commander Kevin Chilton, Onufrienko and
Lucid talked with NASA Administrator Daniel Goldin in Washington, D.C.
Goldin congratulated the crew on the successful docking of the two
spacecraft.

The Shuttle and its now five-person crew is expected to return to
Earth March 31 with a 6:00 a.m. CST landing at Kennedy Space Center,
Florida.

The 230-ton Atlantis-Mir complex is orbiting the Earth every 90
minutes at an altitude of about 240 statute miles with systems on both
spacecraft operating normally.



    

STS-76 Mission Control Center
Status Report # 8

Tuesday, March 26, 1996, 6 a.m. CST

Atlantis' astronauts viewed Comet Hyakutake early this morning as it
continued its close pass by Earth, and they told reporters the comet
was brilliant and could be seen almost from horizon to horizon.

The comments came during an in-flight press conference with the
Atlantis/Mir crews taking questions from reporters at NASA centers and
in Russia.  Although reporting that their glimpse of the comet was
spectacular, the crew has not yet been able to capture it on
televison. The astronauts and cosmonauts also took time out from their
transfer and resupply activities to talk with Charlie Gibson of
'Good Morning America' shortly after 4 a.m. central time today.

For much of the first half of their day, the crew members continued to
transfer water, supplies and science equipment between the two
spacecraft.  More than 1,000 pounds of water, in 10 water containers,
has been moved to the Mir space station to provide drinking and
bathing water for the Mir 21 crew.

The last half of the Atlantis crew's day was devoted to preparing for
Wednesday morning's six-hour spacewalk by Linda Godwin and Rich
Clifford. The hatches between Atlantis and Mir were closed, as was the
hatch between Atlantis and the SpaceHab module. The astronauts then
depressurized the Shuttle's cabin from its standard 14.7 pounds per
square inch to 10.2 psi, a standard pre-spacewalk protocol.  At the
same time, Godwin and Clifford breathed pure oxygen to begin the
process of purging nitrogen from their bodies for the spacewalk. The
SpaceHab and Shuttle-Mir hatches will remain closed until the
spacewalk is completed.

The two spacewalkers currently are scheduled to float out of
Atlantis' airlock just after midnight, marking the start of the
first extravehicular activity to be conducted around the Mir by
American astronauts.  During the spacewalk, four experiment containers
designed to characterize the environment around Mir will be attached
to handrails on the space station.  The packages will be retrieved in
a subsequent spacewalk in about 18 months and will provide information
on the quantity and type of orbital debris and contaminants found in
the same general altitude and orbital inclination planned for the
International Space Station.

The Atlantis-Mir complex continues to orbit the Earth every 90 minutes
at an altitude of about 240 statute miles with systems on both
spacecraft operating normally.

    

STS-76 Mission Control Center
Status Report # 9

Tuesday, March 26, 1996, 5 p.m. CST

The Johnson Space Center Newsroom will reopen at 10:30 p.m. Tuesday in
preparation for the upcoming spacewalk activities.

At 5 p.m. Tuesday, Atlantis' astronauts were nearing the end of
their sleep period, due to awaken at 6:43 p.m.  Preparations for the
spacewalk by astronauts Rich Clifford and Linda Godwin begin at
approximately 8:45 p.m. CST.

The hatches between Atlantis and Mir were closed early Tuesday, as was
the hatch between Atlantis and the SpaceHab module. The astronauts
then depressurized the Shuttle's cabin from its standard 14.7
pounds per square inch to 10.2 psi, a standard pre- spacewalk
protocol.  At the same time, Godwin and Clifford breathed pure oxygen
to begin the process of purging nitrogen from their bodies for the
spacewalk. The SpaceHab and Shuttle-Mir hatches will remain closed
until the spacewalk is completed.

The two spacewalkers currently are scheduled to float out of
Atlantis' airlock just after midnight, marking the start of the
first extravehicular activity to be conducted around the Mir by
American astronauts.  During the spacewalk, four experiment containers
designed to characterize the environment around Mir will be attached
to handrails on the space station.  The packages will be retrieved in
a subsequent spacewalk in about 18 months and will provide information
on the quantity and type of orbital debris and contaminants found in
the same general altitude and orbital inclination planned for the
International Space Station.

Atlantis' astronauts viewed Comet Hyakutake early this morning as
it continued its close pass by Earth, and they told reporters the
comet was brilliant and could be seen almost from horizon to horizon.

The comments came during an in-flight press conference with the
Atlantis/Mir crews taking questions from reporters at NASA centers and
in Russia. The astronauts and cosmonauts also took time out from their
transfer and resupply activities to talk with Charlie Gibson of
"Good Morning America" shortly after 4 a.m. central time today.

The Atlantis-Mir complex continues to orbit the Earth every 90 minutes
at an altitude of about 240 statute miles with systems on both
spacecraft operating normally.


    

STS-76 Mission Control Center
Status Report # 10

Wednesday, March 27, 1996, 7 a.m. CST

Astronauts Linda Godwin and Rich Clifford successfully completed the
first ever spacewalk from a docked Space Shuttle this morning,
installing four experiments on the exterior of the Russian Mir space
station.

Starting at 12:36 a.m. CST, Godwin and Clifford spent six hours, two
minutes and twenty-eight seconds spacewalking in Atlantis's cargo
bay and on the exterior of the Mir's docking module. They smoothly
performed all of the objectives planned for the spacewalk, the most
important of which was to install the four experiments to monitor the
space environment on the exterior of Mir for the next year and a half.

The Mir Environmental Effects Payload, as the experiments are called,
were clamped to outside rails on the docking module. They will gather
information on space debris encountered outside the Mir; the amounts
and types of contaminants around the station; and the corrosive
effects of space on various materials. When retrieved and brought back
to Earth, the experiments will provide valuable insight to engineers
about the space environment likely to be encountered by the future
International Space Station.

Godwin and Clifford also detached a television camera from the outside
of the Mir docking module to return it to Earth, and they evaluated a
variety of new spacewalking tools capable of being used on both
U.S. and Russian spacecraft.

Shortly after the spacewalk was completed, the hatches between Mir and
Atlantis were reopened, reuniting the two space crews. Atlantis'
crew will begin a sleep period at 10:43 a.m. CST and awaken to begin
Day 7 of their mission at 6:43 p.m. CST.

--end--

    

STS-76 Mission Control Center
Status Report # 11

Wednesday, March 27, 1996, 4 p.m. CST

The Johnson Space Center Newsroom closes at 5 p.m. Wednesday and will
reopen at 2 a.m. Thursday for continuing coverage of the STS-76
mission.

The Atlantis astronauts are due to awaken just before 7 p.m. tonight
to begin their final full day of joint docked operations with the Mir
space station.  Transfer of water, supplies and experiment equipment
was nearly completed early Wednesday, moving 1500 pounds of water from
the Atlantis to Mir.

A farewell ceremony is planned for 4:38 a.m. Thursday, followed by
closing of the hatches at 6:43 a.m.  After the crew's sleep period
during the day Thursday, the orbiter will undock from Mir at
approximately 7 p.m. CST.  Atlantis will fly around Mir for about an
hour and a half, taking photos before firing its engines at 8:53
p.m. and dropping into a lower orbit of about 220 nautical miles.

Atlantis is expected to return home Sunday, landing at the Kennedy
Space Center in Florida about 6 a.m. CST.  Weather considerations
could alter the landing site or day of landing.

Earlier Wednesday, astronauts Linda Godwin and Rich Clifford
successfully completed the first ever spacewalk from a docked Space
Shuttle this morning, installing four experiments on the exterior of
the Russian Mir space station.

Starting at 12:36 a.m. CST, the two spent six hours, two minutes and
twenty-eight seconds spacewalking in Atlantis's cargo bay and on
the exterior of the Mir's docking module. They smoothly performed
all of the objectives planned for the spacewalk, the most important of
which was to install the four experiments to monitor the space
environment on the exterior of Mir for the next year and a half.

Shortly after the spacewalk was completed, the hatches between Mir and
Atlantis were reopened, reuniting the two space crews.




    

STS-76 Mission Control Center
Status Report # 12

Thursday, March 28, 1996, 7:30 a.m. CST

The Atlantis and Mir crews bid an emotional farewell to one another
early this morning, in what STS-76 Commander Kevin Chilton called
"a bittersweet moment."

The eight astronauts and cosmonauts exchanged handshakes and hugs in
the Mir core module, and then praised mission control centers in both
Houston and Kaliningrad for their support throughout the joint phase
of the mission.

"We just don't believe that in a few minutes the STS-76 crew will go
through the docking module and we'll say farewell," said Mir 21
Commander Yuri Onufrienko. "We will observe each other only through
the portholes -- they'll be looking at us and we'll be looking
at them.  It will be sad to say farewell to such a good team."

At the start of the farewell ceremony, the Mir crew received a call
from Vladimir Solovyev, Chief Flight Director at Mission Control
Kaliningrad, congratulating the crews on the success of the mission.

With the official goodbyes complete, the eight astronauts and
cosmonauts spent time together for a more personal farewell between
friends.  Hatches between the Shuttle and Mir were closed for the
final time at about 7:15 a.m. today, in preparation for Atlantis'
undocking at about 7:05 p.m. tonight.

When the capture mechanism on the docking module releases and Atlantis
moves away from the Mir Space Station, the STS-76 crew will leave
behind former crewmate Shannon Lucid to begin more than four months of
scientific research on board Mir.  Lucid is inaugurating a continual
American presence on board Mir that will continue to 1998.  Following
tonight's undocking from Mir, Atlantis will fly around the space
station for about an hour and a half, taking photos before firing its
engines at 8:53 p.m. and dropping into a lower orbit of about 220
nautical miles altitude.

Prior to this morning's hatch closure, the crews transferred about
two tons of scientific equipment, logistical material, and resupply
items between the two spacecraft, including 1,507 pounds of water in
15 containers.  They also performed a final check of their inventory
lists to ensure all the transfer activity was complete.

Shortly after 3 am. CST today, Atlantis and Mir commanders Chilton and
Onufrienko, along with spacewalkers Linda Godwin and and Rich
Clifford, took time out to talk with CBS' "Up to the Minute."
The space flyers discussed the success of their joint mission and the
6-hour spacewalk conducted Wednesday by Godwin and Clifford.

All systems on board Atlantis are continuing to perform well, and the
astronauts are turning their attention to final stowage activities as
they conclude the joint portion of the mission.  # # #

    

STS-76 Mission Control Center
Status Report # 13

Thursday, March 28, 1996, 10 a.m. CST

The Atlantis and Mir crews bid an emotional farewell to one another
early this morning, in what STS-76 Commander Kevin Chilton called
'a bittersweet moment.' Atlantis is now scheduled to undock this
evening and land at 6:57 a.m. CST Saturday at the Kennedy Space
Center, one day earlier than originally planned, to avoid predicted
rain and clouds in Florida on Sunday.

The eight astronauts and cosmonauts exchanged handshakes and hugs in
the Mir core module, and then praised mission control centers in both
Houston and Kaliningrad for their support throughout the joint phase
of the mission.

"We just don't believe that in a few minutes the STS-76 crew will go
through the docking module and we'll say farewell," said Mir 21
Commander Yuri Onufrienko. "We will observe each other only through
the portholes -- they'll be looking at us and we'll be looking
at them.  It will be sad to say farewell to such a good team."

At the start of the farewell ceremony, the Mir crew received a call
from Vladimir Solovyev, Chief Flight Director at Mission Control
Kaliningrad, congratulating the crews on the success of the mission.

With the official goodbyes complete, the eight astronauts and
cosmonauts spent time together for a more personal farewell between
friends.  Hatches between the Shuttle and Mir were closed for the
final time at about 7:15 a.m. today, in preparation for Atlantis'
undocking at about 7:08 p.m. tonight.

When the capture mechanism on the docking module releases and Atlantis
moves away from the Mir Space Station, the STS-76 crew will leave
behind former crewmate Shannon Lucid to begin more than four months of
scientific research on board Mir.  Lucid is inaugurating a continual
American presence on board Mir that will continue to 1998. Following
tonight's undocking from Mir, Atlantis will fly around the space
station once, instead of twice as previously planned, before firing
its engines and dropping into a lower orbit of about 220 nautical
miles altitude. Tonight, the crew also will perform checkouts of the
shuttle's flight control systems and steering jets in preparation
for the Saturday landing.

Prior to this morning's hatch closure, the crews transferred about two
tons of scientific equipment, logistical material, and resupply items
between the two spacecraft, including 1,507 pounds of water in 15
containers.  They also performed a final check of their inventory
lists to ensure all the transfer activity was complete.

Thie decision to aim Atlantis toward the one-day-early landing in
Florida was made by shuttle managers this morning. The Kennedy Space
Center is the only landing site that will be considered on Saturday,
with the primary landing opportunity set to begin with a deorbit
engine firng at 5:53 a.m. CST leading to the 6:57 a.m.  CST
touchdown. A second opportunity to land at KSC also exists on
Saturday, starting with a deorbit burn at 7:29 a.m. CST leading to an
8:33 a.m. CST touchdown. The Saturday weather forecast for Florida
predicts light winds and scattered clouds, good weather for a landing.

If Atlantis should have to stay in space until Sunday for any reason,
both KSC and Edwards Air Force Base, Ca., would be considered for a
landing. A total of five opportunities are present for a Sunday
landing, two to KSC and three to Edwards.

All systems on board Atlantis are continuing to perform well.

#  #  #

    

    STS-76 Mission Control Center 
    Status Report # 14
    
    Thursday, March 28, 1996, 8:30 p.m. CST
    
    Space Shuttle Atlantis and the Russian Space Station Mir moved slowly
    away from each other Thursday night, following an undocking at 7:08
    p.m. CST.  Atlantis spent about an hour flying around Mir at a
    distance of 600 feet, conducting a photographic survey.  The shuttle
    initiated a separation burn at 8:07 p.m. central time, dropping into a
    slightly lower orbit and moving ahead of Mir.
    
    Tonight, the crew also was scheduled to perform checkouts of the
    shuttle's flight control systems and steering jets in preparation
    for the landing Saturday at the Kennedy Space Center.
    
    The Atlantis and Mir crews bid an emotional farewell to one another
    early Thursday, in what STS-76 Commander Kevin Chilton called "a
    bittersweet moment." The eight astronauts and cosmonauts exchanged
    handshakes and hugs in the Mir core module, and then praised mission
    control centers in Houston and Kaliningrad for their support
    throughout the joint phase of the mission.
    
    With the separation of the two spacecraft, the STS-76 crew leaves
    behind former crewmate Shannon Lucid to begin more than four months of
    scientific research on board Mir.  Lucid is inaugurating a continual
    American presence on board Mir that will continue to 1998.
    
    Atlantis is now scheduled to land at 6:57 a.m. CST Saturday at the
    Kennedy Space Center, one day earlier than originally planned, to
    avoid predicted rain and clouds in Florida on Sunday.  The decision to
    aim Atlantis toward the one-day-early landing in Florida was made by
    shuttle managers Thursday morning. The Kennedy Space Center is the
    only landing site that will be considered on Saturday, with the
    primary landing opportunity set to begin with a deorbit engine firing
    at 5:53 a.m. CST leading to the 6:57 a.m. CST touchdown. A second
    opportunity to land at KSC also exists on Saturday, starting with a
    deorbit burn at 7:29 a.m. CST leading to an 8:33 a.m. CST
    touchdown. The Saturday weather forecast for Florida predicts light
    winds and scattered clouds, good weather for a landing.
    
    If Atlantis should have to stay in space until Sunday for any reason,
    both KSC and Edwards Air Force Base, CA, would be considered for a
    landing. A total of five opportunities are present for a Sunday
    landing, two to KSC and three to Edwards.
    
    All systems on board Atlantis are continuing to perform well.
    

    STS-76 Mission Control Center 
    Status Report # 15
    
    Friday, March 29, 1996, 6:00 a.m. CST
    
    With the Mir Space Station some 60 nautical miles behind them, the
    Atlantis astronauts are preparing for tomorrow's return to Earth.
    
    Overnight, Commander Kevin Chilton, Pilot Rick Searfoss and Mission
    Specialist Rich Clifford performed a routine checkout of Atlantis'
    flight control surfaces, using a circulation pump instead of an
    auxiliary power unit to route hydraulic fluid to the ailerons,
    elevons, speedbrake and rudder used during reentry. Mission Managers
    elected not to power on the APUs prior to entry to preserve them for
    use during Atlantis' return to Earth.
    
    Auxiliary Power Units 1 and 2 will be powered on as they normally are,
    with APU3, the system associated with the leaking hydraulic unit,
    turned on late in reentry and run in a low pressure, low speed mode
    for use only as a backup system if needed.  All three hydraulic
    systems are expected to be in good working order to support
    Atlantis' landing.
    
    During a hot-fire test of the orbiter's reaction control system
    jets early this morning, three of the 38 primary jets failed, with one
    leaking fuel. The crew closed the left aft manifold and stopped the
    leak.  The loss of these three jets has no effect on tomorrow's
    planned landing since each has at least two jets in the same positions
    that can perform the same functions.
    
    Today, the astronauts will continue stowing some of the final transfer
    items received from the Mir-21 crew and the equipment and checklists
    they have used during their seven days on orbit as they ready Atlantis
    for landing. Mission Specialist Linda Godwin will continue to work
    with the European Space Agency Biorack located in the Spacehab module
    before closing out the module for the final time tonight.
    
    Atlantis is now scheduled to land at 6:57 a.m. CST Saturday at the
    Kennedy Space Center. A second opportunity to land at KSC also exists
    on Saturday, with an 8:33 a.m. CST touchdown.  Edwards Air Force Base
    in California is not being called up to support tomorrow's landing
    attempts, but should weather preclude a Saturday landing at KSC, both
    sites will be available for a Sunday landing.
    
    Weather conditions Saturday at KSC are expected to be good for
    landing, with only a slight concern for early morning ground fog.
    High winds and thunderstorms are expected to move into the area on
    Sunday. Weather at Edwards Air Force Base is predicted to be
    acceptable on Sunday.  A total of five opportunities are present for a
    Sunday landing, two to KSC and three to Edwards.
    
    All systems on board Atlantis are continuing to perform well.
    
    

    STS-76 Mission Control Center 
    Status Report # 16
    
    Friday, March 29, 1996, 4:00 p.m. CST
    
    The Johnson Space Center Newsroom closes at 5 p.m. CST Friday and will
    reopen at 4:30 a.m Saturday for the conclusion of the STS-76 mission.
    
    Astronauts aboard Space Shuttle Atlantis this afternoon were getting
    their final hours of sleep in space before they make final
    preparations for Saturday mornings planned landing in Florida.
    
    Atlantis is now scheduled to land at 6:57 a.m. CST Saturday at the
    Kennedy Space Center. A second opportunity to land at KSC also exists
    on Saturday, with an 8:33 a.m. CST touchdown.  Edwards Air Force Base
    in California is not being called up to support tomorrows landing
    attempts, but should weather preclude a Saturday landing at KSC, both
    sites will be available for a Sunday landing.
    
    Weather conditions Saturday at KSC are expected to be good for
    landing, with only a slight concern for early morning ground fog.
    High winds and thunderstorms are expected to move into the area on
    Sunday. Weather at Edwards Air Force Base is predicted to be
    acceptable on Sunday.  A total of five opportunities are present for a
    Sunday landing, two to KSC and three to Edwards.
    
    

    STS-76 Mission Control Center 
    Status Report # 17
    
    Saturday, March 30, 1996. 8 a.m. CST
    
    Space Shuttle Atlantis and its five member crew will remain in orbit
    one additional day following the wave-off of two landing opportunities
    at Kennedy Space Center today.  Weather for both landing opportunities
    was too dynamic to assure flight controllers that it would be
    acceptable one hour after having to commit to an entry.  Early morning
    fog obscured the landing site on the first opportunity when the
    decision had to be made and apparently increasing low clouds made the
    second landing try too uncertain for comfort.
    
    Atlantis has five landing opportunities for a return home on Sunday,
    two at KSC and three at Edwards Air Force Base, California.  Weather
    forecasters and flight controllers will examine expected conditions
    for each of those times to determine whether all are usable.  The
    first available time is for a 4:47 a.m. CST deorbit burn on orbit 143
    with a 6 a.m. landing at Kennedy Space Center. The second and final
    KSC opportunity is a 6:33 a.m. CST deorbit burn and a 7:29 CST
    landing.
    
    The three Edwards opportunities are: an orbit 144 deorbit burn at 6:25
    a.m. with a 7:29 a.m. landing; an orbit 145 deorbit at 8:02
    a.m. landing at 9:06; and an orbit 146 engine firing at 9:38
    a.m. landing at 10:42 a.m.  All times are Central.
    
    Following the wave-off, astronauts were told they could begin backing
    out of their deorbit readiness condition, reconfiguring orbiter
    systems, opening the payload bay doors and getting out of their suits.
    
    During the stand-down from entry preparations as the astronauts were
    opening the payload doors, there was brief concern when microswitches
    which show the position of a set of door centerline latches indicated
    that they were not fully open, halting the door opening process.  Open
    doors are required to allow the shuttle's radiators to provide
    necessary cooling.
    
    Astronaut Linda Godwin visually compared the latch position with
    drawings and described them as appearing to be fully open. Flight
    controllers asked the crew to operate switches which manually open the
    remaining latches along the starboard door. Once that was done and the
    door appeared to open freely, the full door opening process continued
    without additional delay.
    
    The crew will spend the day conducting Earth observations photography
    and keeping the orbiter ready for entry.
    
    Weather conditions Sunday at KSC are potentially the same or worse
    than Saturday. Weather at Edwards Air Force Base is predicted to be
    acceptable on Sunday.
    
    

It seems that SCA (shuttle carrier aircraft) with Atlantis on top took off from
EAFB on last Saturday, but had to return when 5 minutes after takeoff, they had
an engine fire warning alarm from one of the 747 engines.

They are replacing the engine and hope to have started the trip either last
night or this morning.

Burns