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PART 1: Teacher mentors wanted HELP FROM OTHER TEACHERS
Often, teachers who are new to using an interactive online project like Shuttle Team Online may be a bit confused about how to best use the resources. In the past, we've found that talking with other successful teachers can be a big help. So we would like to make a page which lists willing teacher mentors. Then STO newbies will be encouraged to contact these individuals through email for help with classroom integration. Our past experience shows that no one mentor will be inundated with requests, and they'll always have the option of replying with "I'm too busy, please write to another mentor." As an example of the page we are shooting for, see http://quest.arc.nasa.gov/mars/news/mentors.html So now we need a list of willing mentors. If you have had past success in using Shuttle Team Online with students, please consider becoming a Shuttle Team Online mentor. Please send the following information to marc@quest.arc.nasa.gov - your name - preferred email - grade and subject taught - any specialties (i.e., CU-SeeMe, imaging, work with only one computer for the class, etc) Thanks so much in advance for your help. [Greg is a mechanical systems engineer at the Kennedy Space Center for the group that is responsible for the shuttle's external tank, solid rocket boosters, main engine and thermal protection system.] INSPECTIONS BEFORE LAUNCH AND FILM ANALYSIS AFTER
Greg Katnik http://quest.arc.nasa.gov/space/team/katnik.html July 25, l997 Shortly before launch, we transition from mechanical systems engineering to an operational mode. At this point, the vehicle sits on the pad and launch is getting closer. We are doing many inspections. Almost every day we are walking the vehicle down, from top to bottom, and looking at every square inch. No detail is too small to check. There is a lot of work going on and people moving around. Weather also affects us; we have thunderstorms in the area and many lightning strikes. Because there's so much happening it is necessary to run many inspections and check everything continuously. We then move to the fueling process. We start out in the launch control center. We have console positions; my particular console has access to about forty camera views of the Shuttle. I can call up as many camera views as I want and look at anything. It's like a surveillance kind of duty. Other groups have very specific focus. For example, the people that are working auxiliary power units on the orbiter have telemetry coming in on the power units and perhaps one camera that "sees" them from the outside. They're very focused only on that subsystem. Whereas our group is responsible for the entire vehicle-- we can see the whole Shuttle; scan and move the cameras around; and look at parts that catch our attention or places that we know might have a problem. We watch the fueling process and for ice build-up, which is a very critical concern because it can shake loose during ascent and damage tiles on the Orbiter. The tiles must not be damaged during launch in order to protect the Orbiter during re-entry at the end of the mission. Being in Florida, ice is a weird thing to think about. We have 94 degree weather in the summer and think, "Why is ice even a problem?" Ice can be a problem because hydrogen, with a temperature of -423 degrees Fahrenheit, and liquid oxygen, with a temperature of -297 degrees Fahrenheit, are onboard. In some cases, the Shuttle is like a glass of iced tea sitting in the summer air. The fuel is so cold, it causes water vapor in the air to condense as water on the Shuttle. Therefore, the vehicle becomes wet. If it gets cold enough, this water can then freeze. That's the source of ice on the vehicle. So why are we concerned about this ice attached to a Shuttle at liftoff? If you've ever ridden in a car on the highway and stuck your hand out of an open window while it was raining, you know the rain drops hit hard and can sting. Pieces of ice would be even worse. Ice hitting the Shuttle is like buckshot and can cause a lot of damage. We have to be very careful about how much ice forms and where it forms. So we're watching all of these things, reporting to the rest of the launch team about what we're seeing, and determining what may be a problem and what to do about it. We finally reach a point at which the vehicle is fully fueled and ready to go. I then take a team of seven engineers out to the launch pad and conduct a two hour inch-by-inch inspection from top to bottom, looking at everything on the Shuttle. This inspection is similar to an airliner leaving the gate at an airport where you see the flight engineer or pilot walking around the aircraft and checking everything. At this time, the astronauts are busy having breakfast and getting in their suits. After all of the inspections done over the previous weeks, you might wonder why we have another one, and what is different about it. What's different is that the cryogenic liquids have been loaded on to the Shuttle. The fuel is incredibly cold and causes the vehicle to contract. The External Tank actually shrinks 6 inches when we fill it. That's something remarkable. As an example, take someone living in a northern state like Minnesota where the winter nights can be really cold, like -20 degrees Fahrenheit. What would happen if your car had shrunk 1/2 inch during the night? Doors would probably not open, the pistons wouldn't move, the engine would not start, and the car would probably be virtually useless. The External Tank was designed for this shrinkage. Nevertheless, it's very remarkable for material to shrink that much. The metal "screams" when it shrinks -- it's that cold. So we look for cracks in the metal that may allow fuel to leak out, insulation that's debonded from the metal skin, or anything that could prevent a safe flight as a result of the tanking process. Finally, all the inspections and last minute checks are complete. The crew is on board and we're ready for launch. My team leaves the launch pad and goes back to the launch control center to finish the countdown and launch the Shuttle. After the launch, we are still not done. We go back out to the launch pad to see if there's any damage to the facility, or if the shuttle dropped anything, like a broken tile. In the early days of the shuttle program, there were a couple of incidents in which the vehicle, with the vibration of the engines starting and lifting off, caused tiles to break loose and fall on to the pad. I'm glad to say that has not happened again in a very long time. But if it does, recovering the tiles allows us to read the computer numbers on the them and determine exactly where they originated. We can conduct a thermal assessment to determine if the orbiter could re-enter the Earth's atmosphere safely with or without the missing tiles. So it's very crucial to find any flight hardware that has fallen off right after launch, identify where it came from, and make an assessment. We never know when something is going to happen, so we need to check for this every time. We also look for damage on the launch pad itself--maybe one of the swing arms didn't separate cleanly, or one of the pyrotechnic devices didn't release properly, and the Shuttle may be carrying damage into orbit that we need to know about. So this inspection right after liftoff takes between 2 and 3 hours. By that time, the videotapes from all the shuttle cameras are ready for us to review. We go into a viewing room and look at forty videos for another 2 hours. Reviewing the videos is critical because everything is happening so fast when a Shuttle lifts off, the human eye cannot follow everything. We can run the videotapes in slow motion, freeze-frame, and even backward. The intent is to go through all the videos, frame by frame, to make sure everything operated properly and the Shuttle reached orbit safely and without damage. Or, if we detected a problem, what happened and why--how much can we find out about it just from looking at these videos? We're also pulling telemetry and other data sources into the analysis so that we have a complete story on what might have happened. As an example of this, during the STS-42 mission, we were watching the videos and saw a white object flash past the aft area of the Shuttle. It looked rather big--we knew it wasn't a small piece of ice. We started investigating further and eventually discovered that a carrier panel on the side of the OMS pod had broken off and fallen aft. Once we determined what it was and exactly where it originated from using the photographic data, we were able to perform a thermal assessment and determine that the orbiter could re-enter the Earth's atmosphere without endangering the crew or the spacecraft. We didn't recover the carrier panel because it landed in the ocean. But when the shuttle returned, we examined the fasteners on the OMS pod - how they were installed and what their condition was - and were able to determine what exactly had failed and why. The problem was corrected so another carrier panel falling off would never happen again. The next day, we start getting launch films. We probably have close to 70 film cameras on the launch pad. These are designed to supplement the videos. Video has an advantage in that it can be reviewed almost immediately. But video is slow, and anything that happens really fast does not have good definition on video. So we have high speed cameras all around the pad, which give us a 360 degree view of the vehicle. These are the same types of cameras that can freeze a bullet traveling through an apple. The cameras are focused on a specific part of the launch pad -- a swing arm disconnecting or a pyrotechnic bolt releasing the booster from the pad. We have cameras at the pad perimeter, which can show the entire vehicle clearing the tower. And we have long range trackers that follow the shuttle until we can't see it anymore. We will spend the next three days looking at the films, frame by frame and in slow motion, adding much more detail and resolution to what we already observed in the videos. We have high powered computer digitizers to do in-depth film analysis and enhancing. When the ships recover the boosters in the ocean, we inspect them very thoroughly for any kind of damage, and if there is, we try to understand what happened and if it was a threat to the Orbiter or future flights. During the mission, we continue to follow the operations on-orbit and help out if anything occurs that requires engineering assessment. Finally, we stand on the runway and wait for the shuttle to land. After wheel stop, we start a detailed inspection of the Orbiter. We look for any tile damage from ascent or impacts or cracks in the windows, improper firing of the thrusters, determine if any tile damage occurred from micrometeorites or space debris in orbit, examine insulation on the main engines, and check the tires and brakes for wear and tear. We need to inspect a Shuttle that just landed very thoroughly because the next Shuttle is probably already on the launch pad and close to its launch date. So we need to understand everything that may have happened on the flight that just occurred before we can allow the next one to launch. In summary, we start with a lot of engineering, then go into an operational mode, and then finish a mission as film analysts. Those are the three main jobs that we have in this group. [Editor's note: Tracy works in Experiment Integration, where he gets experiment hardware ready for launch. He installs the hardware and then test all the power, video, cooling, and data interfaces. All this testing helps makes sure that the experiment will work successfully once the mission begins.] A CAMERA'S EYE VIEW FROM THE SHUTTLE
Tracy Gill http://quest.arc.nasa.gov/space/team/gill.html August 22, l997 Standing outside my office building, the Operations and Checkout (O&C) building, I watched the shuttle Columbia launch mission STS-94 from KSC Launch Pad 39A on Tuesday afternoon, July 1. Usually that would signal the end of the work of most KSC personnel for a shuttle mission. However, for five of my co-workers and me from Experiment Integration, our work had a long way to go - seventeen days, in fact, of around-the- clock science operations. We all immediately headed for Orlando International Airport to fly to Huntsville, Alabama, home of the Marshall Space Flight Center (MSFC), where the payload science operations were being controlled while the mission was in flight. All of the engineers, scientists, and mission managers for the experiments on board the Microgravity Science Laboratory (MSL) were there to instruct and to consult with the astronaut crew while the experiments were being performed. We had worked with these people for the last year and a half on STS-83 and STS-94, and we were going to MSFC to assist them with the knowledge we gained while integrating and testing the MSL experiment hardware during pre-launch processing. My five co-workers each worked one shift of around-the-clock monitoring with a specific experiment team. However, my duties were not dedicated to one team. Instead, my mission was to help troubleshoot any problems that occurred with the Spacelab carrier or experiment systems. This was the sixth mission that I had traveled to MSFC to support on-orbit, so I had a lot of experience in working with experiment teams to resolve problems using alternate methods of operations and the tools in the shuttle's In-Flight Maintenance (IFM) Tool Kit. With any luck, I don't have much to do for the whole mission. That makes the time pass pretty slowly for me each day, but I would rather all the experiments work perfectly than have to troubleshoot problems with everything. For this mission, the former was almost the case. We only had a few problems to resolve, and here is the story of the most significant one. The Electromagnetic Containerless Processing Facility (TEMPUS), a German Space Agency-provided experiment facility, has two camera positions that could view the metal samples they were melting and studying inside their furnace. At first, both cameras were working normally, but after only a few hours of operation, the top-view camera became intermittent and then quit altogether. We put together a troubleshooting plan over the course of several days to try some easy fixes, such as powering things off and back on to see if they were being affected by other hardware, and then resetting the cameras to see if that would fix the problem. Another thing we tried was looking at the camera output on the on-board monitor instead of through the satellite downlink to see if it was operating properly in the on-board environment. But none of these things helped. In order to continue with their other science operations, the TEMPUS team rearranged their activities so that all the operations that needed the top-view camera would occur in the second half of the mission. That gave us a few more days to put together a plan for a more invasive troubleshooting plan that would need to get approved by personnel at MSFC, as well as Shuttle Mission Control at the Johnson Space Center. We believed that there may have been a problem involving the sync signal that was being provided to the top-view camera. A sync signal is required for a camera to operate, and a sync signal can be provided externally, in this case by Spacelab, or internally, by the camera itself. I came up with a scheme to access a couple of cables in a fairly convenient location where we could switch the sync signal to the top-view camera with the sync signal that was going to the properly operating front view camera. When we finally got the astronaut crew to do this procedure on-board, we could tell that the problem was related to the camera and not the external sync signal. The second part of my plan was to plug in some jumper wires that would bypass the external sync and allow the camera to operate on internal sync. Lo and behold, it worked. All this effort told us that the electronics that process external sync in that top view camera had degraded. The only disadvantage of operating the camera this way was a small line that ran through the video image because it was no longer on the same sync as the rest of the Spacelab video system, but it was infinitely better to have this small annoyance than no picture at all. The TEMPUS team was elated, and they went on to complete all of their planned activities. When you successfully work your way through a problem, it sure feels good. But when you work your way through a problem with a team of people including international scientists and engineers during a shuttle mission, it feels really great. At the conclusion of STS-94, my five co-workers and I all went back to KSC where we have already started work on the next and probably final Spacelab mission, STS-90, the Neurolab mission, which is scheduled for launch in April of 1998. That one will be focused on life sciences instead of microgravity science. Back to work...see ya. STATUS OF COLUMBIA PROCESSING
Below and in the future, we'll provide some details about the post flight work being done after STS-94 and the subsequent processing of Columbia as it gets ready to fly again as STS-87. These reports will contain jargon and unfamiliar terms; our intent is not to confuse you, but to provide a glimpse at all the steps involved. 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 Since the last updates-sto message, work to install the strut pyrotechnic device for Columbia's nose landing gear was completed. The Shuttle's drag chute was installed and structural leak checks are in work. Installation of the remote manipulator system was concluded. Inspections of the sector seals on the rudder speed brake are underway. Weight saving modifications to the orbiter's elevons continue. Fuel cell monitoring modifications are under way in an effort to improve crew accessibility to voltage readings. Modifications in the crew module were completed; work is now underway in the orbiter's midbody. Final draining of the Shuttle's oxidizer cross-feed line and a leak check are complete. A damaged section of the line has been removed and is undergoing failure analysis. A replacement section of line is was fabricated and installed. Window polishing is ongoing and Columbia's window No. 7 is slated for replacement. Preparations began for installation of Shuttle main engines No. 1 and No. 2. Main engine No. 3 is slated for installation in late September. STS-87 SCHEDULED OPERATIONAL MILESTONES (dates are target only): Shuttle main engine installation begins (Sept. 8)
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