Mission Status Report #1 Thursday, June 25, 1992 12:30 pm central time The Space Shuttle Columbia was launched into orbit this morning with a crew of seven to begin a record-setting two weeks of microgravity experimentation in Earth orbit. The 12th flight of Columbia - first since it's refurbishment - got underway at 11:12 am central time with enough fuel and supplies onboard to keep the crew and their United States Microgravity Laboratory in operations around the clock for thirteen da ys. Columbia is currently in a 220 nautical mile orbit and astronauts are busy activating the electrical, environmental, and data processing systems that will support their complex laboratory. The crew will be operating in alternating 12 hour shifts des ignated the Red Team - consisting of Crew CDR Dick Richards, pilot Ken Bowersox, Payload CDR Bonnie Dunbar and payload specialist Larry DeLucas - and the Blue Team consisting of mission specialists Carl Meade and Ellen Baker, and payload specialist E ugene Trinh. The Blue Team will start their first sleep shift at about 2:45 pm central time today and will relieve the Red Team tonight just after 10 pm. Columbia appears to be in excellent shape and, assuming all goes well, plans are for a landing on July 8th at Edwards Air Force Base in California in the early morning. MISSION CONTROL CENTER STS-50 Status Report #2 Thursday, June 25, 1992, 5 p.m. CDT Payload activities are underway as the seven-member crew of Columbia settles into the work routine for the record-setting 13-day United States Microgravity Laboratory-1 mission. Mission Specialist Bonnie Dunbar performed the 16-step procedure to activate the Spacelab module without any problems. Accompanied by Pilot Ken Bowersox and Payload Specialists Larry Delucas and Gene Trinh, she entered the laboratory for the first time about 2:45 p.m. Central. Activation was completed about 3:48 p.m. For STS-50, the crew members have split into two teams to cover 24-hour payload operations. Red Team members are Dunbar, Bowersox and Delucas and Blue Team members are Mission Specialists Ellen Baker and Carl Meade and Payload Specialist Gene Trinh. Commander Dick Richards will align his schedule with the Red Team for the mission. Six hours into the mission, the orbiter is performing well. For the 13- day flight, Columbia is carrying four extra cryogenic oxygen and hydrogen tanks sets courtesy of the new Extended Duration Orbiter pallet riding in the payload bay. Richards, however, performed the group B priority powerdown to conserve energy for the flight. The powerdown procedures calls for placing one of the three navigation units in standby and turning off extra lights, CRTs and other none essential equipment. Currently, Columbia is circling the Earth once every 90 minutes in a 163 by 160 nautical mile orbit. MISSION CONTROL CENTER STS-50 Status Report #3 Friday, June 26, 1992, 8 a.m. CDT Mission Control had a quiet night as Columbia completed its first day in orbit with the United States Microgravity Laboratory-1. Onboard the spacecraft, the Red Team of crew members -- Commander Dick Richards, Pilot Ken Bowersox, Mission Specialist Bonnie Dunbar and Payload Specialist Larry DeLucas -- have just begun their second work shift of the flight, relieving their Blue Team counterparts. Blue Team crew members will go to sleep for their second night in space at about 11:10 a.m. CDT. Flight controllers did detect a slight leak in one of the eight oxygen tanks carried by Columbia, but the quantity of oxygen being lost due to the leak is not large enough to have any impact on the mission. Oxygen from the eight tanks is combined with hydrogen from eight sister tanks to generate the spacecraft's electricity. The eight oxygen-hydrogen tank sets aboard Columbia are the most ever flown on a shuttle and are needed to allow the spacecraft enough electricity to stay in orbit for 13 days. Four tank pairs are mounted in Columbia's fuselage and four additional tank pairs are mounted on a special pallet in the cargo bay. The slight leak is from an oxygen tank mounted in the fuselage. At its present small rate, the oxygen leak will not impact the ability to power all equipment and experiments aboard Columbia as planned for the entire 13-day flight. However, flight controllers plan to use oxygen from the tank earlier than had been originally scheduled so that there would be no impact to the flight even if the leak were to become larger. Oxygen is leaking from the tank at about four-tenths of a pound per hour, and each tank holds 781 pounds of oxygen when full. Columbia remains in a 164 by 160 nautical mile high orbit, circling Earth every 91 minutes. MISSION CONTROL CENTER STS-50 Status Report #4 Friday, June 26, 1992, 4:30 p.m. CDT Payload activities are the order of the day as Columbia and its seven-member crew spend the second full day in space. On its 12th mission, Columbia continues to perform very well with only a few minor problems being tracked by flight controllers in Houston. Earlier today, crew members performed a malfunction procedure to recover Controller 2 of the Regenerative Carbon Dioxide Removal System. The RCRS is a new system to scrub the carbon dioxide from the crew cabin and module air and is designed to eventually replace the lithium hydroxide canister system. The malfunction seen several times today is a false indication to the RCRS's logic system from a valve position sensor that automatically shuts the RCRS down which would be proper if the indications were true. Switching to Controller 1 is not an option since the same malfunction was seen there earlier in the mission. Each time the malfunction message was received, crew members performed a procedure to bring the system back up. Even if the system were to go down for the remainder of the mission, Columbia is carrying enough lithium hydroxide canisters for the full 13-day mission. Crew members today also reported the return of a whistling sound near the Waste Containment System coming from an air outlet duct. The crew can partially manage the noise level, and flight controllers are studying the problem. Columbia remains in a 164 by 160 nautical mile high orbit, circling Earth every 91 minutes. STS-50 MCC STATUS REPORT #4 (REVISED) Friday, June 26, 1992, 5:00 p.m. CDT Payload activities are the order of the day as Columbia and its seven-member crew spend their second full day in space. On it's 12th mission, Columbia continues to perform very well with only a few minor problems being tracked by flight controllers in Houston. Despite several efforts by crew members to revive it, the Regenerative Carbon Dioxide Removal System appears to have failed. The RCRS is an experimental system designed to replace the old lithium hydroxide canisters as a method for removing carbon dioxide from the cabin air. For the time being, the system will be left off and the job of cleansing the cabin air will be left to the lithium hydroxide system with no impact expected to the duration of the flight. Crew members also reported that a high-pitched whistling sound has returned to the Waste Containment System-- apparently from an air outlet duct. The noise does not affect the operability of the system, however, flight controllers are studying the problem. Columbia remains in a 164 by 160 n.m. orbit, circling Earth every 91 minutes. MISSION CONTROL STATUS STS-50 Status Report #6 [Mislabeled -PEY] 4 p.m. CDT Saturday, June 27, 1992 Houston flight controllers had a quiet afternoon today as Columbia remained in excellent condition and crew members devoted their time to payload activities. During their 34th orbit, crew members were asked to reconfigure the cryogenic oxygen and hydrogen tanks. This activity signalled the completion of a precautionary plan to use the oxygen from the slowly- leaking Tank 2 early in the mission. The flight control team opted to deplete Tank 2 to the 55 percent mark to protect consumables margins in case the 0.4 pound per hour leak grew. Also today orbiter crew members worked with the Investigations into Polymer Membrane Processing and Shuttle Amateur Radio Experiment. IPMP, sponsored by Battelle Advanced Materials Center in Columbus, Ohio, studies the physical and chemical processes that occur during the formation of thin polymer membranes in microgravity. Commander Dick Richards performed the experiment which involved turning several valves on the IPMP hardware to allow the membranes to form and fix. Richards also reported contacting amateur radio operators across the United States. He also reported receiving a planned fast-scan television transmission from California. Flight controllers continue to monitor their systems but at this time are not tracking any anomalies with the orbiter. MISSION CONTROL STATUS STS-50 Status Report #7 8 a.m. CDT Sunday, June 28, 1992 Columbia kept an overall clean bill of health last night, and flight controllers concentrated on assisting ground scientists as they workedwith the crew to explore weightlessness in the United States Microgravity Lab. A paper jam late yesterday halted use of Columbia's Text and Graphics System (TAGS), a specially designed space fax machine that allows printed materials and even photographs to be sent to the spacecraft. To send printed material, flight controllers are now using the teleprinter aboard Columbia. Additional information is being sent to the crew via a specially built air-to-ground computer modem that allows electronic mail between a portable computer on Columbia and Mission Control. Several attempts to clear the paper jam from TAGS were unsuccessful, and controllers are now looking at other possible repair plans. In addition, controllers are discussing the possiblity of attempting a repair of the Regenerative Carbon Dioxide Removal System, a new device being tested on Columbia that scrubs the cabin air and dumps carbon dioxide from it overboard. When the device was taken out of service Friday, the crew began using the standard operation for cleaning cabin air, lithium hydroxide canisters that must be removed and replaced with fresh canisters periodically. Enough such canisters were packed aboard Columbia to last for the entire mission. The Red Team is currently at work on the spacecraft after waking up for their fourth day in space shortly after 5 a.m. central time. Columbia remains in a 164 by 160 nautical mile orbit, circling Earth once every one hour, thirty minutes and thirty-six seconds. MISSION CONTROL STATUS STS-50 Status Report #8 4 p.m. CDT Sunday, June 28, 1992 Columbia continues to provide a stable platform for the Spacelab module in the payload bay containing the United States Microgravity Laboratory experiments while flight controllers in Houston kept watch on the orbiter's systems. Only the troubleshooting of the onboard fax machine interrupted a nominal fourth flight day for Columbia. A paper jam halted use of the machine Saturday and several subsequent attempts to clear the device proved unsuccessful. Printed material is now being set to the crew via the teleprinter and a specially designed air-to-ground computer modem that transmits electronic mail to the crew. With Columbia's systems in good shape, Commander Dick Richards has had ample time to communicate with ground-based amateur radio operators using the Shuttle Amateur Radio Experiment equipment. Throughout the day, Richards reported successful radio contacts with operators around the world and with school students in LaPorte and Corpus Christi, Texas. Crew members also had an opportunity to watch the Russian space station Mir fly above them shortly after nine Saturday morning. Mir was about 50 miles above and 70 miles to the left of Columbia. The Blue Team aboard the orbiter was scheduled to get up shortly after 5 p.m. to relieve the Red Team which has been on shift in the Spacelab since early Saturday. The dual-shift operation allows the microgravity investigations to continue 24 hours a day. MISSION CONTROL CENTER STS-50 Status Report #9 Monday, June 29, 1992, 9 a.m. CDT Columbia operated trouble-free overnight, with flight controllers performing normal day-to-day operations and assisting payload controllers with their investigations when needed. After a crystal growth experiment was found to be shut down, controllers changed Columbia's orientation to expose different surfaces of the spacecraft to the sun, thus assisting in keeping those areas warm. Columbia is now positioned with its underside toward the sun. Anytime that science investigators agree it is possible and will not disturb the experiments under way, Columbia will be moved to that orientation to assist in moderating temperatures. But for the majority of the flight, Columbia will be in the gravity gradient position. The gravity gradient orientation allows the spacecraft to remain relatively stable with very few steering jet firings that could disturb experiments and use propellant. Flight controllers are continuing to discuss attempting repair of the regenerative carbon dioxide removal system, a new device being flown for the first time on Columbia. It was taken out of service after about one day of operation. The RCRS basically dumps carbon dioxide from the cabin air overboard, and could eventually reduce the number of lithium hydroxide canisters, currently in use on Columbia, that must be carried on each flight. Although the canisters are working well on Columbia, controllers would like to have the RCRS working in order to gain more information on how well it can cleanse the cabin air over long periods. Columbia is in a 159 x 164 nautical mile orbit. MISSION CONTROL STATUS STS-50 Status Report #10 Monday, June 29, 1992, 4:45 p.m. CDT In a break from the sensitive microgravity investigations, Columbia burned its reaction control systems jets this afternoon to adjust its orbit during another smooth day for STS-50. Performed to provide a backup deorbit opportunity on the nominal end of mission day, the 39-second burn lowered Columbia's orbit slightly to 160 by 159 nautical miles. Shortly afterwards, the orbiter returned to an attitude with its tail pointing toward Earth and its payload bay pointing about 12 degrees off the direction of travel. Such a position allows the orbiter to remain stable for long periods of time without jet firings that might disrupt the sensitive microgravity experiments. In Houston, flight controllers are reviewing and discussing plans to attempt to repair the regenerative carbon dioxide removal system. The device, which scrubs carbon dioxide from the orbiter's air, failed earlier in the flight when a sensor provided false inputs to the RCRS's logic system subsequently causing automatic shutdowns. Since that time, crew members have been using the traditional lithium hydroxide canisters to cleanse the air. The orbiter and crew are in excellent condition and flight controllers have no new systems problems to track. MISSION CONTROL STATUS STS-50 Status Report #11 Tuesday, June 30, 1992, 8:30 a.m. CDT Some early household repairs and continuing science are the order of the day aboard Columbia, which continued to perform without problems overnight. About 8:30 a.m CDT, Pilot Ken Bowersox and Commander Dick Richards began a planned three-hour repair attempt on a new piece of equipment being flight-tested that removes carbon dioxide from the cabin air by dumping it overboard. Although the standard form of controlling carbon dioxide aboard the shuttle -- replaceable lithium hydroxide carbon-dioxide absorbing canisters -- has been working well, engineers would like to fix the regenerative carbon dioxide removal system to gain more information about how well the system works over long periods. The new system was taken out of service after the first day of the flight when a faulty sensor reading continually caused it to shut off. In today's repair attempt, Bowersox and Richards will pull out four middeck lockers to gain access to the shuttle's lower deck, under which the RCRS is mounted. They'll remove the top cover panel of the device, and unplug one electronic wire connector. >From the bundles of wire in the connector, they will locate four specific wires and splice two together and then another two together. The spliced wires will bypass the sensors that have been giving false readings to the systems automatic controller, thus halting the false alarms that were the cause of continual shutdowns. The repair is estimated to take about three hours. Also today, members of the Red Team -- Richards, Bowersox, Bonnie Dunbar and Larry DeLucas -- appeared live on ABC's Good Morning America. Columbia is in a 160 x 159 nautical mile orbit. MISSION CONTROL STATUS STS-50 Status Report #12 Tuesday, June 30, 1992, 5 p.m. CDT Columbia's new Regenerative Carbon Dioxide Removal System is up and running again following the completion of a procedure to bypass faulty sensors in the air scrubbing unit. Pilot Ken Bowersox assisted by Commander Dick Richards spent the morning working through the 32-step procedure that started with the removal of four middeck lockers to gain access to the RCRS unit. Using tools in the orbiter's in-flight maintenance kit, Bowersox disconnected one of the electrical connections at the top of the unit and spliced two sets of wires to bypass sensors that relayed faulty indications that shut the system down earlier in the flight. Since the procedure was completed, the RCRS has worked well. The unit will provide engineers with important data about the operation of the RCRS as a replacement of the traditional lithium hydroxide canister system. Advantages of the RCRS include saving weight and stowage space previously used for the canisters and freeing the crew of the canister changeout task. As microgravity investigations proceeded in the Spacelab module today, Richards continued his work with the Shuttle Amateur Radio experiment. Among his contacts around the world, Richards talked briefly with students at Hockaday School in Dallas. Columbia continues to perform very well with no new systems anomalies reported. The orbiter is circling the Earth once every 90 minutes at an altitude of 160 by 159 nautical miles. MISSION CONTROL STATUS STS-50 Status Report #13 Wednesday, July 1, 1992, 8:30 a.m. CDT Approaching the halfway point of the longest shuttle flight ever, Columbia is flawless, and flight controllers report there are plentiful supplies of electricity, air, fuel, food and other consumable items aboard. Early today, crew members concentrated on amateur radio contacts in addition to starting a busy shift of weightless experiments in the Spacelab. The crew reported talking to Boy Scouts from Troop 195 in Galina, Ohio, early this morning. Also, Payload Specialist Larry DeLucas talked with coworkers and relatives at the University of Alabama in Birmingham, Alabama. Commander Dick Richards is planning to make several more ham radio contacts during the day, including talking with students at Hyatt Elementary School in San Jacinto, Calif. and at Addison Elementary School in Marietta, Ga. An adjustment on the shuttle amateur radio was intended to ground the antenna better, and ham radio operators on the ground report all communications have been very strong. Richards, along with Mission Specialist Bonnie Dunbar, will talk with professional radio as well today in an interview with CBS News Radio scheduled for 11:12 a.m. CDT. Television from the spacecraft is not planned for the interview, but the audio will be broadcast live on NASA Select. Richards and Pilot Ken Bowersox each exercised for about an hour this morning, riding a stationary bicycle on Columbia's flight deck. Bungee cords secured the bike and are being checked out as a secondary method of lowering the amount of vibrations the bike might cause to the sensitive experiments on board. An electromagnetic shock- absorbing system used when the bike is on the shuttle's lower deck has been very successful in minimizing vibrations as well. Columbia is in a 160 by 159 nautical mile orbit, circling Earth every one hour, thirty minutes and thirty-one seconds. MISSION CONTROL STATUS STS-50 Status Report #14 Wednesday, July 1, 1992, 5 p.m. CDT Columbia finished another day in excellent condition as the seven- member crew approached the half-way mark in the 13-day mission. Commander Dick Richards confirmed the on-going health of the orbiter when he completed the redundant component checkout earlier today. The check of many of the orbiter's backup systems is a routine procedure for long-duration missions. Components checked today included various system fans, freon pump loops and water loops. Richards also continued his work with the Shuttle Amateur Radio Experiment by using the orbiter's ham radio equipment to talk with students at Hyatt Elementary School in San Jacinto, California and Addison Elementary School in Marietta, Georgia. The Regenerative Carbon Dioxide Removal System continues to work very well following Tuesday's sucessful in-flight maintenance procedure by Pilot Ken Bowersox. Payload Commander Bonnie Dunbar and Payload Specialist Larry Delucas took advantage of planned off-duty times, taking breaks from their payload activities. Columbia continues to circle the Earth once every 90 minutes in a 160 x 159 nautical mile orbit. MISSION CONTROL CENTER STS-50 Status Report #15 Thursday, July 2, 1992, 8 a.m. CDT Now more than halfway through its twelfth mission, NASA's oldest orbiter continues to perform nearly flawlessly allowing the crew to devote full attention to the experiments in the Spacelab module and to view the release of a chemical in the upper atmosphere after being launched on a small rocket. Much of the orbiter Columbia activities during the last 12 hours involved routine systems maintenance ensuring the health of all components to support the remainder of the mission. During the early morning, the waste water tank was dumped which is required about every three days. Also performed was an alignment of the navigation units and a supply water dump using the flash evaporator system. The FES, as it is known, is a subtle way to discharge excess water so as not to disrupt the orbiter's stable attitude in support of the many experiments being conducted in the 23-foot- long laboratory. Columbia's crew had a unique opportunity to view the chemical release of barium from a cannister carried aboard a small rocket launched from Puerto Rico at 4 a.m. The chemical release occurred at an altitude of 135 nautical miles about two minutes after launch of the rocket. At the time of the rocket launch, Columbia had just crossed the equator 160 nautical miles above the Earth. Crewmember Ellen Baker reported having a "pretty good view" of the barium cloud as the orbiter approached the island from the southwest on its 108th orbit. Columbia remains in a stable attitude to support science activities as it circles the Earth every 90 minutes. MISSION CONTROL CENTER STS-50 Status Report #16 Thursday, July 2, 1992, 5 p.m. CDT Just into the second week of their projected record-setting mission, the astronauts aboard Columbia continued their science harvest today, focusing on studies of fluid dynamics, crystal development, and hydroponic plant growth. From the flight deck of Columbia, crew commander Dick Richards made several successful radio contacts with students on Earth, using amateur radio equipment flown for just that purpose. Richards spoke with students at the Carolyn T. Douglas School in Massachusetts in a long-distance lashup through Honolulu and Corpus Christi ham radio relay stations. Later, in the afternoon, he chatted with students from three schools in Johannesburg, South Africa. By the request of the Argentine Embassy in Washington, the crew was asked today to observe and photograph heavy flooding along the Pirhana and Uruguay rivers in Argentina, as their orbital path took them directly over the South American country late this afternoon. This evening, Richards and pilot Ken Bowersox will guide Columbia in a very slow, steady maneuver to point it's underside towards the sun for several hours in order to warm up mechanical systems and to help maintain adequate air pressure in the main landing gear tires. The tire pressures, which normally decay at a slight but steady rate, are a bit lower than were predicted for this point in the flight. By periodically applying heat to the area, the air in the tires will be warmed, thus increasing the air pressure in the tires and slowing the decay rate. At this point, flight controllers believe that periodic warming will assure more than adequate tire pressures for landing. All systems aboard Columbia continue to operate without problem while the Orbiter remains in a stable attitude for science activities - circling the Earth every 90 minutes or so. STS-50 MISSION CONTROL STATUS REPORT #20 5:00 p.m. CDT Saturday -- July 4, 1992 The astronauts aboard Columbia wished America a happy birthday today in a videotape featuring views of the United States from space, and Lee Greenwood's song, "God Bless the USA." Crew members also videotaped themselves assembled in front of a large American flag draped above the entrance to their science laboratory, saying, "We know it's a special day down there, it's a special day up here, too." While the videotape was being played to the ground, Payload Specialist Larry DeLucas was serving as the subject of the Lower Body Negative Pressure investigation - an effort that occupied most of the science crew's time today. LBNP, as it is known, is intended to draw body fluids to the lower limbs by means of negative pressure - or vacuum, in an effort to recondition the cardiovascular system to the effects of gravity. It is hoped that LBNP will help prepare astronauts for readaptation during and after the return to Earth. Just after noon central time, payload commander Bonnie Dunbar reported smelling something like "wiring insulation" coming from a vent of the American Echocardiograph Research Imaging System, or AERIS. The AERIS provides blood volume measurements to the experimenters during LBNP operations. Neither fixed smoke sensors nor the hand-held combustion products analyzer detected any traces of smoke, however, as a precaution, the system has been turned off for the remainder of the mission. The loss of that system will not affect the continuation of LBNP operations. During the afternoon, crew commander Dick Richards reported a very successful amateur radio contact with the Polynesian canoe Hokulea which is making a star-navigated voyage from Honolulu to the Cook Islands. Gifted students from the Hawaiian Island s also listened in and spoke with Richards from a radio relay station at the University of Hawaii. The relay station was used to connect the ocean-bound vessel with Columbia in orbit. At 3 p.m. central time, the crew maneuvered their spacecraft back to the gravity gradient attitude for crystal growth furnace operations and will remain in that position until late Sunday. All orbiter systems are in great shape, and the crew remains on top of the planned timeline. STS-50 MISSION CONTROL STATUS REPORT #21 8:00 a.m. CDT Sunday -- July 5, 1992 Wrapping up another successful morning of science, the Blue Team handed over control of Columbia and its Spacelab to the Red Team, which awoke at 3:30 this morning. Much of today's activities center around continued data gathering from experiments in the pressurized facility including the lower body negative pressure device. LBNP is being conducted almost daily aboard Columbia to determine its usefullness in helping astronauts condition their bodies for readapting the Earth's gravity upon return from long-duration Shuttle and other space missions. Columbia's electricity usage continues to fall below the predictions by about one kilowatt, ensuring enough hydrogen and oxygen are available for the rest of the record breaking mission. Power currently is being supplied from tanks located on the new extended duration orbiter pallet located behind the Spacelab module in the payload bay. About 8:14 tomorrow morning, Columbia will break its own record for the longest Shuttle mission to date, eclipsing STS-32's mark of 10 days 21 hours and one minute set in January 1990. A computer problem at the White Sands Ground Terminal in New Mexico was the only problem worked by the overnight flight control team. White Sands acts as the relay station of data and voice transmission to and from the orbiter. All systems aboard Columbia continue to perform well, with no vehicle problems being tracked by flight controllers in Mission Control as the orbiter circles the Earth every 90 minutes at an altitude of 162 nautical miles. STS-50 MISSION CONTROL STATUS REPORT #22 5:00 p.m. CDT Sunday -- July 5, 1992 All systems aboard Columbia continue to perform well, with no vehicle problems being tracked by the flight control team, as the Red Team turns Spacelab operations over the to Blue Team at 5:13 p.m. Today's activities included evaluation of the double rack foot restraint in a configuration that duplicates the foot restraints planned for Space Station Freedom. Other work included conditioning astronauts for return to Earth using the lower body negative pressure device, continuing protein crystal growth, and taking retinal photographs for a biomedical experiment. Commander Dick Richards contacted students at Lowell Elementary in Winfield, Kansas, using the Shuttle Amateur Radio Experiment ham equipment. The Red Team participated in television interviews with Jim Slade for ABC news and with Michele Gillen for NBC news. As a wrap-up for the NBC interview, payload commander Bonnie Dunbar took viewers on a tour of the Spacelab module, describing some of the material science and life science experiments onboard. About 8:14 tomorrow morning, Columbia will break its own record for the longest Shuttle mission to date, eclipsing STS-32's mark of 10 days, 21 hours and one minute set in January 1990. Columbia is scheduled to land at Edwards Wednesday, July 8, at 8:08 a.m. CDT. At the conclusion of this mission, the U.S. total man-hours in space will be 64,610 hours, 33 minutes, and 27 seconds. MISSION CONTROL CENTER Status Report #23 Monday, July 6, 1992, 8:30 a.m. CDT Columbia's twelfth mission officially has become the longest in Shuttle program history, surpassing the previous record of 10 days 21 hours set in January, 1990 on the STS-32 flight. The song "Stay" was played from Mission Control to the crew in honor of the achievement shortly after the record was broken at 8:13 a.m. central time today. Flight controllers are beginning to take a closer look at weather conditions for the landing opportunities at Edwards AFB in California. The forecast for Wednesday's landing time of 8:08 a.m. C.D.T. calls for scattered clouds and head winds of 10 knots gusting to 16 on runway 22. The predicted location of hurricane Darby at the time of landing adds the possibility of some lower clouds with moisture in the Edwards area. Prior to start of its sleep period, the Blue Team aboard the orbiter -- Ellen Baker, Carl Meade and Gene Trinh -- along with Commander Dick Richards met with CBS This Morning to discuss the progress of the mission. Near the end of an orbiter maneuver last night, excessive thruster jet firings were detected. While not expected, the firings posed no danger to the crew or experiments, and is thought to be due to maneuvering on one of the modified digital auto pilot settings. Future orbiter maneuvers will be done using a different setting. All other orbiter systems remain healthy as Columbia continues on its record-setting mission. MISSION CONTROL CENTER STS-50 Status Report #24 Monday, July 6, 1992, 5 p.m. CDT On their record-setting 12th day in orbit, the astronauts aboard Columbia reported spectacular crystal formations developing in their space laboratory, and did some physiological conditioning in preparation for the return to Earth on Wednesday. In addition to their daily Orbiter maintenance routine, pilot Ken Bowersox and crew commander Dick Richards took time to exercise using a cycle ergometer, to maintain good cardiovascular conditioning, while Bonnie Dunbar and Larry DeLucas continued their conditioning using the Lower Body Negative Pressure device. Houston flight controllers are beginning to make more frequent assessments of predicted weather conditions around Edwards AFB in California for Wednesday's landing. The latest forecast for a landing at 8:08 a.m. central time calls for good conditions - scattered clouds with light and variable winds. Blue team members Carl Meade, Ellen Baker, and Gene Trinh will take over operations aboard Columbia at 6 central time tonight as they begin their last full work day dedicated to microgravity sciences. Tomorrow evening, the Blue team will begin the process of stowing gear and powering down the laboratory in preparation for landing Wednesday morning. All systems aboard Columbia continue to perform without problems. MISSION CONTROL CENTER STS-50 Status Report #25 Tuesday, July 7, 1992, 8 a.m. CDT Preparations for the trip home began aboard Columbia as the crew finished up work with several experiments in the Spacelab module and checked out the flight control surfaces used to fly the spacecraft after it enters the Earth's atmosphere. Final data were gathered from the Drop Physics Module, Lower Body Negative Pressure Device and Protein Crystal Growth experiments and all were deactivated for the remainder of the flight. Pilot Ken Bowersox powered up one of three hydraulic system units used to test the moving surfaces on the wings and tail of the orbiter. Commander Dick Richards then proceeded through the routine process of checking the aerosurfaces for tomorrow's landing at Edwards AFB in California. Sharing console time in Mission Control with the regular shift of flight controllers was the entry team, which watched over the crew's shoulders via data screens during the flight control surface checkout, and reviewed all pertinent messages relating to landing. Prior to conducting the checkout, the STS-50 crew answered questions about its mission in an interview with the "Today" program. Latest predicted landing time shows touchdown on Edwards runway 22 at 8:05 a.m. central. The deorbit burn using the 6000 pound thrust maneuvering engines to drop Columbia out of orbit will occur about one hour earlier. Weather forecasters predict a slight chance of rain in the Edwards area associated with hurricane Darby located southwest of California in the Pacific. While the storm is weakening, cloud bands carrying moisture is the concern. Should weather preclude landing on Wednesday, forecasters say improvement is expected Thursday at Edwards. The backup landing site for this mission -- Kennedy Space Center in Florida -- is forecast to have stable weather both days. MISSION CONTROL CENTER STS-50 Status #26 Tuesday, July 7, 1992, 5 p.m. CDT The astronauts aboard Columbia are nearing the end of their marathon mission and a return to Earth in the morning at Edwards Air Force Base in California. Landing is set for 8:09 a.m. central time, 6:09 a.m. pacific -just 24 minutes after sunrise at the Mojave desert landing strip. Their final full day in orbit has been spent completing the final phases of microgravity experiments, preparing material samples for return to Earth, and stowing equipment, charts, and manuals for the trip home. Experiment deactivation will continue through the night with final deactivation of the laboratory itself getting underway just after midnight tonight. The deactivation is expected to be completed by 2:30 a.m. central time Wednesday. Two minor orbiter system issues developed today - one, involving a slight gaseous nitrogen leak from a hydraulic pump component, was rectified simply by turning it off and selecting one of two backup pumps. The other involved some blockage in the waste water dumpline. To avoid contributing any further to the blockage, waste water dumps have been terminated for the flight - there is sufficient room in the waste tank to support through the end of the mission without any further dumping. With those exceptions, Columbia continues to operate extremely well. Landing gear tire pressure remains in good shape despite a slow and steady decay rate, and will easily support landing well above the safety limits. Weather is predicted to be favorable for a Wednesday morning landing in California, with mid-level scattered clouds, high-level broken clouds, and light and variable winds. There is only a slight chance of rain in the area. Should weather preclude landing on Wednesday, improvement is expected for Thursday. The backup landing site for this mission -- the Kennedy Space Center in Florida -- is expected to have stable weather both days. The de-orbit burn, which initiates the freefall back into the atmosphere, is scheduled to occur at 7:06 a.m. central time. During freefall, all seven crew members will be taking salt tablets and drinking 32 oz. of water in order to replenish body fluids lost during their two-week stay in space. The fluid-loading technique should help the crew in their adaptation to the influences of Earth's gravity. Assuming a landing, on time, at 8:09 a.m. central time, the crew should return to Houston's Ellington Field by about 6 p.m.