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UPDATE # 17 - July 3, 1997 PART 1: The Mission Evaluation Room (MER)
- JSC Engineering During a Mission
THE MISSION EVALUATION ROOM (MER) - JSC ENGINEERING DURING A MISSION
Stokes McMillan http://quest.arc.nasa.gov/space/team/mcmillan.html June 26, l997 I work on console at JSC every day during a Space Shuttle mission. Before I can write a journal about my experiences during STS-94, I must introduce you to where I work and what I do. I work in the Mission Evaluation Room or MER (rhymes with sir) and I am a MER Manager. Here's an explanation: The organizations responsible for flying the shuttle can loosely be divided into two groups: operations and engineering. "Operations" personnel are charged with flight planning, training, and execution. During a mission, operations personnel manage the flight. NASA's best known operations group is JSC's Mission Control Center (MCC) which controls the daily activity on-board the shuttle from liftoff to landing. "Engineering" focuses mostly on the performance of the shuttle hardware. It consists of the people who maintain and upgrade the many components that constitute the shuttle. Many of these people are the ones who designed the original shuttle components. They focus on the daily operation of these components during a mission, as well as maintaining them throughout the entire shuttle fleet over several missions. Each piece of equipment in the shuttle has one or more engineers responsible for it. When it malfunctions, the responsible engineers determine why it broke, and what can be done to fix or work around it during a mission. They decide if a redesign is necessary to keep it, and other components like it, from breaking again. These engineers know their components better than anyone else and are a valuable source of information. To give a simplified illustration of the different roles of the two groups during a mission, let's say that one of the shuttle's five general purpose computers (GPC) stops operating during the flight. The flight controllers in MCC direct the crew through procedures attempting to regain the GPC. When the computer stays failed, MCC replans the remainder of the mission to take into account having four instead of five GPCs. Engineers pour over data from the failed computer trying to determine why it failed. Is the problem some design or manufacturing flaw that could soon show up in one or more of the other four computers (a generic failure), or is it just a random failure? Determination of a generic or a random failure can have a big effect on the remainder of the mission. Engineering may develop a special test to be performed while on-orbit to gain insight in the failure mode. Just as operations personnel have the Mission Control Center in which they monitor shuttle missions, engineering personnel also have a large room where they monitor the performance of their subsystems during a mission. It is the Mission Evaluation Room - the MER. Just like MCC, the MER has been around since spaceflights were first flown from JSC. The MER and MCC are located on different floors in the same building at JSC. The MER consists of several consoles where the engineers sit. Each console has data display screens and keyboards, computers, headset communication equipment, and TV monitors showing the mission. Scattered throughout the MER are stripchart recorders, bookcases containing scores of technical data on the shuttle, more TV monitors and more computers. The MER has one person leading the activity of the room and speaking for it: the MER Manager. In my next journal entry, I'll talk about this job. MER MANAGER
Stokes McMillan http://quest.arc.nasa.gov/space/team/mcmillan.html June 27, l997 In my first journal, I told you about the difference between space shuttle operations and space shuttle engineering. I introduced you to the Mission Evaluation Room (the MER), the place where shuttle engineering personnel sit to monitor a mission. In this installment I'll go into more detail on the MER and introduce you to the MER Manager. The MER, representing JSC's shuttle engineering organization, is a sister-facility to the Mission Control Center (MCC), the most visible part of the shuttle operations organization. The MER is not directable by MCC, so it can form its own opinions and make its own recommendations concerning shuttle hardware. This check and balance system has served NASA well for decades. Like MCC, however, the goal of us in the MER is to have a safe and successful space shuttle mission. We are all part of the NASA team. The MER has frequent contact with MCC to either give or receive information in identifying, resolving, or preventing shuttle hardware problems. During highly active shuttle mission periods like launch and entry, the MER is home to well over 100 engineers monitoring the performance of their particular shuttle components. In the middle of the night when the crew is asleep during a clean (few failures) mission, there may be no more than a dozen engineers in the MER. It would be mass confusion if each engineer were allowed to contact his MCC counterpart. To avoid this confusion, NASA has tasked one MER position to be the voice of the MER, communicating with and providing a single decision or recommendation to the "outside world" (MCC, KSC, NASA management, etc.). This is the MER Manager. The MER Manager is the authorized leader of the MER and is ultimately responsible for the products and decisions coming from there. He or she makes the task assignments for problem analysis or information requests coming into the MER. MER Managers ensure that the work being done by the various MER engineering positions proceeds in the priority and detail necessary to support mission events. There is one MER Manager on console at all times during a shuttle mission. Sitting next to him is the Assistant MER Manager who assists the MER Manager in running the MER. Shift times run from 6:00 AM to 2:00 PM (first shift), 2:00 PM to 10:00 PM (second shift), and 10:00 PM to 6:00 AM (third shift). The on-coming MER Manager arrives on console one hour ahead of these times in order to thoroughly come up to speed on all that has happened in the 15 hours since his previous shift. At present there are four active MER Managers. We rotate shifts through a four-mission cycle in the order of first, second, third, off. The MER Manager who is off for a mission generally substitutes when needed for illness, vacation, etc. We usually work an entire mission, with maybe a day off in the middle of a long (two week) mission to recharge our batteries. What's the most popular shift? It may surprise you, but with most of us it is third. This is usually the least hectic mission shift, especially when the crew is asleep. Traffic and parking are no problems, of course, and the area around JSC is just quieter and more peaceful in the middle of the night. Often the shuttle's payload bay cameras are pointed to Earth, and we on console watch the world go by in real time on our TV monitors. It's a great way to learn geography. We just have to grin and bear it through the first two or three days while our internal body clock gets adjusted to being 12 hours out of sync. The first shift MER Manager is the lead MER Manager for that particular mission. Prior to the mission, he is responsible for being expert on the mission, attending and holding mission-related meetings, writing memos to shuttle engineering and MER Manager personnel containing mission information, schedules and personnel assignments, and ensuring the MER is ready to support. During the mission, the lead MER Manager attends a set of daily meetings. He chairs a 7:00 AM meeting where representatives from each shuttle engineering group briefs him on the status of their systems. At 8:00 AM, he briefs NASA's Mission Management Team on the status of the shuttle (the Orbiter itself, not payloads or mission events) and makes recommendations when necessary. (As the lead MER Manager on STS-83, it was my duty to make the formal recommendation to shut down the fuel cell which shortened the mission. This was done after many meetings with fuel cell engineering personnel from around the country.) Finally, at 10:00 AM he leads a meeting to discuss the anomalies that have occurred during the flight. Here it is decided which anomalies need to be investigated/fixed by KSC and which ones are elevated to the status of "flight problems." More special meetings are called when made necessary by mission events. While the lead MER Manager is away in these meetings, the Assistant MER Manager runs the MER. As you can see, mornings are usually very busy for the first shift MER Manager and Assistant MER Manager. Usually around 11:00 AM the MER Manager gets back on console and can review all that has happened while he was in morning meetings. Then he starts preparing for the handover to second shift. I am the lead MER Manager for STS-94. According to my calculations this will be my 30th mission to be a MER Manager and the 11th to be lead MER Manager. Today is Friday, June 27, 1997. Assuming we remain on schedule to launch STS-94 on Tuesday, July 1 at 1:37 PM CDT, my assistant Pat Oliver and I will begin MER console support Monday morning at 8:00AM (we try to start support prior to L-24 hours). I plan to write a journal entry as often as I can during the mission to give you an inside view of the mission and what goes on with the Orbiter. Some of my narrative may get technical, but I'll try to keep it in English as much as possible. Along the way you'll learn more about how the MER much as possible. Along the way you'll learn more about how the MER operates. STS-94 LAUNCH FROM THE CONSOLE IN THE MISSION EVALUATION ROOM
Stokes McMillan http://quest.arc.nasa.gov/space/team/mcmillan.html July 1, l997 I arrived on the MER Manager console at 5 AM to find everything in good shape. The External Tank was in the early stages of being loaded with liquid oxygen and hydrogen and there were no signs of leakage. All three fuel cells were up and running and looking totally normal. This was a relief since the last time Columbia flew, STS-83, its fuel cell #2 had started out looking different. Its operating parameters were within launch limits, however, so we launched. This fuel cell began degrading soon after we reached orbit. It had to eventually be shut down, causing the early termination of STS-83. So it was good to see STS-94's fuel cells starting out on the right track. The concern for the day's launch attempt was predicted to be weather. Summertime at KSC often brings afternoon thunderstorms, and the winds were predicted to be in a condition conducive to thunderstorm development. They were supposed to get worse later in the afternoon. Because of this, NASA management had decided on Monday to advance the launch by 47 minutes from 1:37 CDT to 12:50 CDT. As the countdown proceeded, the Orbiter stayed clean. The MER engineers were working no problems with Columbia. As predicted, however, the weather degraded. At sunup the sky was mostly clear blue. By midmorning KSC time there were plentiful white, puffy cumulus clouds, and these were producing rain and lightning in areas. All eyes were on the radar display of KSC. The thunderstorms seemed to be forming mostly west of KSC and moving southwesterly. Hope! Then a camera on the roof of KSC's huge Vertical Assembly Building (VAB) looking at launch pad 39A and Columbia three miles away showed a huge rainstorm between the two. Time marched on and the weather stayed iffy. We got to the planned 10 minute hold at T-20 minutes. I polled the MER engineers looking for a go to come out of the T-20 minute hold. No problems. I passed this on to my boss who was in the firing room at KSC. We picked up the count until the planned 10 minute hold at T-9 minutes. Once in the hold I again polled the engineers and got a favorable response to continue the count and passed this to KSC. Meanwhile, stray thunderstorms in the area caused an additional 12 minutes of hold time until the weather guys (called Weather) could give a go to continue. We picked up the count at T-9 minutes. With three or so minutes to go, Weather spotted a small shower within our 20 mile limit of the pad. It was southwest of the pad and quickly moving southeast, away from Columbia and the landing strip that would be necessary should we abort the flight right after liftoff. Continue the count. Columbia lifted off at 1:02 PM CDT on a very clean ascent to orbit. We had two minor anomalies during ascent. A water spray boiler which is supposed to keep the lubrication oil to the auxiliary power unit #3 (which supplies hydraulic power to Columbia) less than 275 deg. F let the oil get to 281 deg.F before it kicked in. This will have no effect on the mission. Also, a steam vent duct temperature dropped to 175 deg. F where it should have stayed above 190 deg. F. Again, this will have no effect on the flight. Two very minor glitches. I'm constantly amazed that such an incredibly complicated machine can fly from the ground to earth orbit in a little over 8 minutes and not have more go wrong. And this is a machine on its 23rd flight in over 16 years. And it last flew less than three months ago. There's no doubt that those folks at KSC are the world's best at preparing and launching space vehicles. There's a flagpole on top of JSC's building 30 which houses the MER and MCC. Only the U.S. flag flies there, and it only flies when there's a shuttle in space. It's flying now. STATUS OF STS-94
Below we'll provide some details about launch and the post launch activities surrounding the STS-94 flight. Detailed daily reports about Columbia's processing can be found at the NASA Shuttle Status web site at http://www-pao.ksc.nasa.gov/kscpao/status/status.htm Also, we'll share the status of the STS-94 mission as it unfolds. This material comes directly from the Shuttle Web site at http://shuttle.nasa.gov Columbia lifted off from Pad 39A on Tuesday, July 1 at 2:02 p.m. EDT on a reflight of the Microgravity Science Laboratory mission. NASA managers decided Monday to move up the launch time by 47 minutes to avoid expected afternoon thunderstorms. The launch was delayed by about 12 minutes for forecasters to assess a rain storm located 20 nautical miles from KSC's Shuttle Landing Facility. Despite discouraging forecasts on Monday, weather conditions were favorable at the time of launch. The solid rocket booster retrieval ships, Freedom and Liberty, arrived at Hangar AF Wednesday, day 2 at about 1:30 and 2:30 p.m. respectively. All booster elements were recovered and rinsing activities are in work today (Thursday, July 3). Initial inspections will begin on Monday morning. The astronauts on board the space shuttle Columbia remain on course with their 16-day agenda of microgravity science research, using the Spacelab module riding in the payload bay and the 33 experiments of the Microgravity Science Laboratory payload as a test bed for procedures and hardware planned for use on the International Space Station. One advantage of having a second chance at this flight was that, after looking at the postflight information from STS-83, they were able to redesign the first experiment, changing some of the parameters, so the results of the first run on STS-94 are much better than from either of the runs on STS-83. One of the challenges of this flight is the coordination required when the crew operates in two teams around the clock. As you follow the reports online, you can see that there is a blue team and a red team, and a great deal of care must be taken as one team turns over responsibility to the other, making sure all the information gets communicated across to the other crew about the continuing experiments.
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