baalke@mars.jpl.nasa.gov (Ron Baalke) (10/10/89)
GALILEO DAILY REPORT
9 OCTOBER 1989
NOTE: This report covers the activities of 6-9 October
General
Spacecraft
The RTGs were installed on 7 and 8 October. Spacecraft
Launch Conditioning was subsequently performed and completed
successfully.
Final spacecraft closeouts have been performed. The
spacecraft is now in a complete ready state for launch; the
discrete from the IUS at L-20 min. is the only remaining
prelaunch command to be sent.
STS
IUS: The only scheduled operation was the open circuit
voltage checks on the flight batteries. This was completed
successfully on 7 October.
The PLBD (payload bay doors) were closed at approximately
12:45 p.m. on 9 October.
Details
Spacecraft
At 0200 hours on 7 October, JPL performed the final
preparations for RTG installations at Launch Complex 39B.
During the removal of the end-blocks (used for testing the
cooling loop when the RTGs are not installed) from the ACS
(Airborne Cooling System), a JPL technician alertly detected a
foreign object in the supply side to the RTG cooling line.
Approximately 40 psi of nitrogen pressure was used in an
unsuccessful attempt to clear the line. The pressure was
subsequently reduced to approximately 20 psi and hemostats were
used to remove the debris which was later identified as a piece
of foam porous pad. The foam pads are used to temporarily seal
the lines from contamination any time a joint of the system
plumbing is broken. This is the same type of material
previously reported as the cause of the earlier RTG cooling loop
problem (see Report #78).
Meetings were held between JPL and Lockheed
engineers/managers. It was decided to perform a boroscope
examination of the sharp bends of the cooling system immediate
interface to the RTG. Test results showed the bends to be
clean. Based on these results and the fact that approximately
equal nitrogen flow was obtained through each RTG branch with a
nitrogen flow, it was decided to proceed with the installation
of the RTGs without any additional action.
The RTGs were delivered to the base of the launch pad at
approximately 6:30 p.m. 7 October. The first RTG was hoisted to
the PCR (Payload Changeout Room) but operations were then
interrupted for approximately 1 1/2 hours by lightning storms.
The -x RTG was then installed without any problems except during
the mating of the PRD (pressure release devices) to the RTGs;
the screw lengths were too long and two additional washers had
to be installed on each of the two screws. The second RTG was
then hoisted and installed without any problems; washers were
also installed on the PRD screws. The operation was completed
at approximately 2:30 a.m. on 8 October.
At 0400 hours on 8 October, during the process of applying
the planned short to the -x RTG by an external S.E. box, it was
discovered that the meter went to approximately 25 volts instead
of near zero. The spare shorting box was then used and the
appropriate reading obtained. The problem was later found to be
in the meter. The process for applying RTG power to the
spacecraft continued without any further problems.
At the conclusion of powering the spacecraft from the RTGs,
at approximately 0610 hours on 8 October, the conditioning of
the spacecraft for launch commenced. Launch conditioning was
completed at approximtely 6:00 p.m. on 8 October. Memory
compares of the spacecraft memory contents to the memory load
have been completed and it has been reported as being successful
at approximately 0300 hours on 9 October.
The PRD safe pins have been removed on 9 October and the
carry-on umbilicals disconnected. The spacecraft portion of the
carry-on umbilical connectors have been capped and the related
thermal blanket installed.
The PGHM and RTG installation platforms have been placed in
a configuration that allowed the orbiter PLBD (payload bay
doors) to be closed; the PLBDs were closed at approximately
12:30 p.m. on 9 October.
Schedule Discussion and Assessment
Launch is still scheduled for 12 October at 1:29 p.m. EDT.baalke@mars.jpl.nasa.gov (Ron Baalke) (10/11/89)
GALILEO DAILY REPORT
10 OCTOBER 1989
General
Spacecraft
The spacecraft is in is launch ready state as previously
reported.
The spacecraft continues to be monitored 24 hours a day
both at KSC and at Pasadena. There have been no problems to
date.
LCET
LCET #1 was returned to the VPF (Vehicle Processing
Facility) area on 9 October. All communications, power, and
power cables have been installed.
LCET #1 is now operational and monitoring the spacecraft
telemetry derived from the composite telemetry through the T-0
cabling. Telemetry alarms matching those of the MTS have been
inserted and are operational. This provides a backup capability
in case the lines to JPL become inoperative.
Schedule Discussion and Assessment
The launch at this time is still scheduled for
12 October at 1:29 p.m. EDT.
Ron Baalke (818) 541-2341
Jet Propulsion Lab M/S 301-355
4800 Oak Grove Dr.
Pasadena, CA 91109baalke@mars.jpl.nasa.gov (Ron Baalke) (10/13/89)
GALILEO DAILY REPORT
11 OCTOBER 1989
SPECIAL ANNOUNCEMENT: 17 October at 12:57 p.m. EDT is the new
launch date for Galileo.
General
Spacecraft
The spacecraft is still in its launch ready state and is
being monitored constantly both at KSC and at Pasadena.
A PF/R was opened, analyzed, and dispositioned on the
attachment of the PRDs (Pressure Release Device) to the RTGs.
LCET
LCETs #1 and #2 are both being manned around the clock when
spacecraft telemetry analysis is in process.
Details
Spacecraft
The spacecraft continues to operate satisfactorily from
power supplied by the RTGs. However, temperature control
engineering has requested that the orbiter air conditioning to
the spacecraft be raised from 52 deg F to 58 deg F. The basis
of this request was the RPM temperature which is at its lower
acceptable limit as specified in the launch commit criteria.
The orbiter temperature was raised as per JPL's request on the
evening of 10 October. Appropriate paper is in process that
will allow the inlet temperature to be varied from
48 deg F to 60 deg F. This in turn will allow for any future
adjustment as a normal operation of the prelaunch activities.
As reported on 9 October, during the mating
of the PRD (Pressure Release Device) to the RTG two additional
washers were installed on each of the four screws used to attach
the PRDs to each of the RTGs. Questions were raised on the
action taken, that is, the installation of the washers. PF/R
54340 was opened to document the concern expressed by General
Electric. Subsequent analysis was made on the overall
incident. The primary points were: 1) that during the insertion
of the screws the engagement of the screws into the insert
locking mechanism was misinterpreted as the screw bottoming out,
2) two washers were added to reduce the gap which in turn
reduced the amount of screw engagement in the insert locking
mechanism, 3) both JPL and GE engineers agreed that the last one
turn into the locking mechanism was required, 4) the JPL
technician, that did the hands-on work, and the engineer, that
witnessed the work, agreed that two screw turns into the locking
element were achieved, 5) that there would be no impact to the
mission if one screw backed out. Additional analysis was done
at JPL, and after review of the total picture, the Project
Manager declared that no further action was necessary; in short,
that the attachment of the PRDs to the RTGs was satisfactory.
Schedule Discussion and Assessment
It was announced this afternoon that the new launch date is
17 October at 12:57 p.m. EDT. The count will be resumed on
Monday, 16 October at L-19 hours at 5:57 p.m. EDT. Shortly
after the countdown is picked up the IUS is scheduled to be
powered for its final prelaunch conditioning and checks.
Ron Baalke (818) 541-2341
Jet Propulsion Lab M/S 301-355
4800 Oak Grove Dr.
Pasadena, CA 91109baalke@mars.jpl.nasa.gov (Ron Baalke) (10/17/89)
GALILEO DAILY REPORT
16 OCTOBER 1989
General
NOTE: This report covers the activities of 14-16 October
Spacecraft
The spacecraft still remains in its launch ready state.
The next spacecraft event will occur at L-20 min when a command
is received from the IUS to turn on the DMS (Data Management
System) and remove the bias from the HIC and EPD science
instruments.
There has been only one additional CDU (Command Detector
Unit) subcarrier lock indications since 11:57 p.m. on 12 October.
This occurred today at 11:12 a.m. There is no JPL concern
regarding these locks; they do have a finite probability of
occurring and more so in presence of a commercial carrier near
the center band of the receiver.
Spacecraft telemetry has been stable during this period
without any changes in temperatures, etc.
LCET
LCET #1 and #2 are in a ready state to support the pre
launch and post launch activities up to and including
acquisition by the DSN (Deep Space Network).
STS
A L-2 Day status meeting was held at KSC on
15 October. All systems, including the spacecraft, gave their
"go" for launch on Tuesday, 17 October.
Today, 16 October, the L-1 Day telecon was held between all
systems and the astronauts. Again, all systems gave their "go"
for launch on tomorrow, Tuesday.
"The Galileo spacecraft is ready for launch and has had
essentially housekeeping chores during the standdown.
Launch is scheduled to occur at the opening of the launch
window or at 12:57 p.m. (EDT). The window for tomorrow closes
at 1:23 p.m. (EDT)." KSC Public Affairs Office, 16 October 1989
Ron Baalke (818) 541-2341 ext 260
Jet Propulsion Lab M/S 301-355
4800 Oak Grove Dr.
Pasadena, CA 91109baalke@mars.jpl.nasa.gov (Ron Baalke) (10/18/89)
GALILEO DAILY REPORT
17 OCTOBER 1989
General
The launch countdown went down to T-5 minutes but due to
adverse weather at KSC, which would have affected the return of
the Atlantis to the base, it was decided to scrub the launch and
retry tomorrow, 18 October. The opening of the launch window is
12:50 p.m. EDT terminating at 1:17 p.m. Retanking of the
orbiter is scheduled to occur at 4:00 a.m. EDT on 18 October.
Ron Baalke (818) 541-2341 ext 260
Jet Propulsion Lab M/S 301-355
4800 Oak Grove Dr.
Pasadena, CA 91109baalke@mars.jpl.nasa.gov (Ron Baalke) (10/19/89)
GALILEO DAILY REPORT
18 OCTOBER 1989
General
STS 34, with Galileo aboard, was launched from KSC at
12:53 p.m. EDT on 18 October 1989. Once in orbit the IUS went through
a predeployment checkout. A "Mission Phase 6" error did occur when attempting
to lock in the RF link to Sunnyvale through the PI (Payload Integrator), but
this was determined to be static on the RF link. The tilt table was then
raised up to a 58 degree angle, and Galileo was deployed at a time of
6 hours 21 minutes 23.397 seconds after launch, on the 6th orbit around
the earth.
The tilt table was then lowered back down to its initial -6 degrees. At
about 15 minutes after deployment Atlantis executed a separation burn. Live
pictures were then transmitted to Houston control showing the payload bay area
and the inside of the shuttle. At 7 hours 21 minutes after launch the 1st stage
IUS burn was executed and verified by Sunnyvale. The 2nd stage UIS burn
occurred 5 minutes later to place Galileo on an Earth escape velocity of
7.1 miles/sec. The VTR playback of the Galileo deployment was then transmitted
to Houston.
Debris looking like ice particles was seen to be floating around the
shuttle. Houston control questioned the crew about what the debris could be.
At 7 hours 46 minutes after launch, the IUS went into a 1st stage spinoff
to deploy the RTG and science booms. The 2nd stage IUS spinoff at a rate of
2.9 revolutions/second for the separation of the IUS from Galilio sooned
followed. At this point telemetry data were transmitted and recieved by
DSN (Deep Space Network).
Galileo is expected to arrive at Venus in February 1990 on its first
leg of its journey to Jupiter.
Ron Baalke (818) 541-2341 ext 260
Jet Propulsion Lab M/S 301-355
4800 Oak Grove Dr.
Pasadena, CA 91109spinkert@pikes.Colorado.EDU (Scott Casto Pinkerton) (10/20/89)
In article <1939@jato.Jpl.Nasa.Gov> baalke@mars.jpl.nasa.gov (Ron Baalke) writes: > The 2nd stage IUS spinoff at a rate of >2.9 revolutions/second for the separation of the IUS from Galilio sooned >followed. Was this correctly printed ?? The IUS spun itself and the payload up to 174 RPM prior to separation ?? That seems like an incredible controls problem to prevent the stack from spinning in a very wide "cone". Also at actual separation, the CG will jump back some 30-40 feet maybe (don't know actual Galileo dimensions) - again sounds like one hell of a controls problem. Was this meant to be 2.9 RPMinutes ??
wilkins@jarthur.Claremont.EDU (Mark Wilkins) (10/21/89)
In article <2832@pikes.Colorado.EDU> spinkert@pikes.Colorado.EDU (Scott Pinkerton) writes: >In article <1939@jato.Jpl.Nasa.Gov> baalke@mars.jpl.nasa.gov (Ron Baalke) writes: >>2.9 revolutions/second for the separation of the IUS from Galilio sooned >>followed. > >Was this correctly printed ?? The IUS spun itself and the payload up to >174 RPM prior to separation ?? That seems like an incredible controls >problem to prevent the stack from spinning in a very wide "cone". Also at >actual separation, the CG will jump back some 30-40 feet maybe (don't know >actual Galileo dimensions) - again sounds like one hell of a controls >problem. Was this meant to be 2.9 RPMinutes ?? Sometime if you ever get the chance watch some of the footage of one of those satellites with an IUS being launched. When STS-26 went up many at our school watched the TDRS deployment and the thing was rotating about one or two times each second during the deployment from the cargo bay. Galileo is (I think) smaller than TDRS and I would not be surprised at 2.9 revolutions per second, especially after the IUS has carried the thing some distance from the shuttle. -- Mark Wilkins
baalke@mars.jpl.nasa.gov (Ron Baalke) (10/31/89)
GALILEO STATUS UPDATE
30 OCTOBER 1989
Galileo is now 2.5 million miles from Earth traveling at 59,845 mph as
it slowly drops in towards the orbit of Venus. Its radio transmitter
is now operating at 30 watts and its propulsion system has been
operated twice in tests and for maintainence purposes. Galileo's
atmospheric probe has been checked out last week and its condition is
fine. The spacecraft's ion detector was turned on during the latter
part of the solar flare and has measured heavy ions in the range of
130 million volts, none of which affected Galileo's electronics. On
Wednesday, the spinning of the lower part of the spacecraft where the
optical sensors are mounted will be stopped. At present the whole
spacecraft is spinning at 2.9 revolutions per minute. The top part
of Galileo where controller electronics, power, propulsion, radiation
and magnetic field sensors, and radio attennas are located will
continue spinning for the duration of the mission.
Ron Baalke | (818) 541-2341 x260
Jet Propulsion Lab M/S 301-355 | baalke@mars.jpl.nasa.gov
4800 Oak Grove Dr. |
Pasadena, CA 91109 |baalke@mars.jpl.nasa.gov (Ron Baalke) (11/02/89)
GALILEO WEEKLY STATUS
October 30, 1989
This is a weekly Galileo status report. Today,
October 30, 1989, the spacecraft is about 2.5 million miles from
Earth, and has gone 16.7 million along its 2.4-billion-mile
spiral course to Jupiter. Its velocity around the Sun is almost
60,000 mph. All subsystems are working well.
Since launch, operators have sent hundreds of real-
time commands to the Galileo spacecraft. The S-band transmitter
has been switched to 30 watts, and the propulsion system has been
exercised twice in maintenance maneuvers (primarily to move
oxidizer and fuel along in the plumbing.) The telemetry rate is
7.68 kilobits per second.
As of this morning, the spacecraft is spinning at 2.9
rpm around an axis within 1 degree of the Sun line. As Galileo
progresses around towards Venus, the Sun angle changes; this is
held to less than 14 degrees, by commanded or automatic
maneuvers, to assure a shaded spacecraft.
The atmospheric entry probe was checked out last
Thursday, October 26, and its condition is satisfactory. The
imaging system and the near-infrared mapping spectrometer
were checked out Friday, with good results. Preparatory
activities for various other science instruments are being
done, but the only instruments actually turned on and taking
data are the magnetometer and the HIC.
The heavy ion counter, an engineering instrument
modified from parts of a Voyager cosmic-ray sensor, was
turned on ten days ago and detected the latter part of the
solar flare of October 19. Heavy ions of energies up to 130
MEV (million electron volts) have been detected, but the
spacecraft has experienced no single-event upsets (i.e., no
ill effects.)
Today the star sensor on the spinning section is to
be checked out, in preparation for Wednesday's start of dual-
spin operations. The lower section of the Galileo spacecraft
will be spun in reverse, with electric motors, stopping the
rotation and despinning the science scan platform.
The first trajectory-correction maneuver, TCM-1, is
scheduled, in three instalments, for November 9, 10 and 11.
Ron Baalke | (818) 541-2341 x260
Jet Propulsion Lab M/S 301-355 | baalke@mars.jpl.nasa.gov
4800 Oak Grove Dr. |
Pasadena, CA 91109 |yee@trident.arc.nasa.gov (Peter E. Yee) (11/02/89)
To prevent further duplication of work, Ron and I have agreed that Ron will post *all* Galileo status reports and information briefs. I'll do the rest of the NASA postings. -Peter Yee yee@ames.arc.nasa.gov ames!yee
baalke@mars.jpl.nasa.gov (Ron Baalke) (11/08/89)
GALILEO WEEKLY STATUS
November 7, 1989
As of 8 a.m. (PST) Tuesday, November 7, 1989, the Galileo
spacecraft is 4.16 million miles from Earth, 28.2 million miles
along its path to its first gravity assist at Venus. Round-trip
light time is almost 45 seconds. Galileo still has 157 million
miles to go just to reach Venus; it is reducing that distance at
a rate of just over 60,000 mph, increasing slowly as it comes
closer to the Sun. Jupiter lies about 2.4 billion miles ahead
along the VEEGA trajectory.
The spacecraft is spinning at about 3 rpm around an axis
pointed a few degrees from the Sun. It is transmitting telemetry
at 7.68 kilobits per second; the RTG's are providing about 570
watts of power, 60 watts more than needed at present. The heavy
ion counter, an engineering instrument which detects charged
particles from the atomic weight of carbon through that of iron,
has been seeing at least one every 2/3 second, mostly oxygen. It
detected and characterized the recent major solar flare.
Last week Galileo's flight team continued checkout,
maintenance, and characterization of various elements of the
spacecraft. Notable among these was the dual-spin mode, in which
a major part of the spacecraft, carrying the scan platform with 4
instruments, the probe and probe relay system and associated
electronics, was spun in reverse while the rest of the machine was
still spinning at about 3 rpm. This mode, which allows the camera
and other remote-sensing instruments to be aimed at planetary
targets, was satisfactorily maintained during the 70-minute
checkout.
The spacecraft was then put back in the all-spin mode for
other planned cruise operations. These included sun pointing
(moving the spin axis from about 10 down to 1.25 degrees from the
Sun line). Before and after this maneuver, the star sensor was
given a star map and turned on to determine attitude and spin rate,
which it did as planned. An additional propulsion system
maintenance sequence was done early Monday.
The first trajectory correction maneuver is planned for
November 9, 10, and 11; it will change the spacecraft velocity by
less than 17 meters per second (about 38 mph). Small axial and
lateral thrusters will fire in pulses of about 1-sec duration.
Nothing in the mission so far has ruled out the possibility
of an asteroid encounter (Gaspra, between the first and second
Earth flybys). However, no final decision on asteroid encounters
will occur until after the Venus flyby in February, when Galileo's
flight team and other project personnel evaluate the post-Venus
flight path and the propellant margins at that time.
Ron Baalke | (818) 541-2341 x260
Jet Propulsion Lab M/S 301-355 | baalke@mars.jpl.nasa.gov
4800 Oak Grove Dr. |
Pasadena, CA 91109 |baalke@mars.jpl.nasa.gov (Ron Baalke) (11/15/89)
Galileo Status Report
14 November 1989
The first course change maneuver for Galileo was successfully completed
last Saturday. The two day maneuver began last Thursday morning at a distance
of 28,200,000 miles from Earth, and consisted of a long series of time pulses
of Galileo's 2.2 pound thrusters. A shorter continuous period of firing would
have overheated the thrusters.
The total speed change was 38 mph which will move Galileo closer to its
target point near Venus, but changes the arrival time to Venus on February
9th by only a few minutes.
During the maneuver, a temperature sensor on one of the thrusters failed.
However, in the future the temperature of that thruster can be deduced from
nearby thruster readings.
Galileo is now 55,162,000 miles from Earth and traveling at 60,807 mph.
After gaining momentum from Venus's gravity, Galileo will return to Earth
in December next year, use Earth's gravity to loop out to the asteroid
belt, and return back to Earth again two years later for a final gravity
push to reach Jupiter in December 1995.
Several more days of tracking are needed to determine the accuracy of
last week's course change.
Ron Baalke | baalke@mars.jpl.nasa.gov
Jet Propulsion Lab M/S 301-355 | baalke@jems.jpl.nasa.gov
4800 Oak Grove Dr. |
Pasadena, CA 91109 |