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Timeline of Events as of 3/18/03

Jan 16, 2003

09:39am CST

• Columbia lifts off on the STS-107 mission. At T+~80 seconds a large fragment of what it believed to be External Tank insulation and/or  Condensational Ice apparently detaches and falls from the External Tank. This will not noticed until a routine frame by frame analysis of videos taken during the launch performed the next day.

09:49am CST

• The shuttle is safely in orbit and the crew begins to unpack gear.

11:30am CST

• The crew opens Columbia's payload doors and exposes SPACEHAB, a pressurized laboratory module that contains 59 of the 80 scientific experiments to be conducted during the mission. Also on board: a special pallet of cryogenic fuel tanks to provide Columbia and its experiments sufficient electrical power for the duration of the flight.
   
• The seven astronauts were divided into two teams — Red and Blue — so experiments could be run around the clock during the entire 16-day mission in space.

Jan 17, 2003

• NASA engineers standard frame-by-frame analysis of the launch footage notice the incident. An engineering team is assembled to examine the strike and determine possible threats to Columbia.

04:39am CST

• The Red Team, consisting of mission commander Rick Husband, mission specialists Kalpana Chawla and Laurel Clark and payload specialist Ramon, are woken by Mission Control. Atmosphere experiments measuring the sun's energy, the Earth's ozone layer and dust in the Mediterranean Sea begin.

06:39pm CST

• The Blue Team, consisting of shuttle pilot Willie McCool, mission specialist Dave Brown and payload commander Mike Anderson, are awakened and take over for the Red Team.

Jan 18, 2003

04:39am CST

• The Red Team wakes up and starts on the day's work. In addition to atmosphere research, the crew begins life science studies, including one studying calcium loss in bones during space flight.

02:00pm CST

• Red Team members take a break and conduct interviews with Earth-based news reporters. Israeli astronaut Ramon says he views the mission as an "opening for great science for our nation."

05:39pm CST

• Blue Team members are roused from their sleep to take over the second shift. In addition to continuing Red Team's work, members will begin experiments examining soot formation, lean combustion and fire suppression in the Combustion Module, or chamber.

Jan 19, 2003

• Both Red and Blue teams continue their research, mainly related to material science.
   
• TV cameras capture Ramon working in the shuttle's Combustion Module. He reports that the experiment facilities aboard Columbia were operating perfectly.
   
• During the evening shift, one of two systems designed to collect and distribute water produced from condensation buildup caused by the operation of the cooling system in the SPACEHAB Research Module springs a leak and is shut down. The secondary unit takes over and operates normally.

Jan 20, 2003

• Engineers report to a "debris assessment team."

01:15pm CST

• Flight controllers on the ground notice a minor electrical spike in the second unit that took over cooling duties in the SPACEHAB module. Engineers work a plan out with the crew to reconfigure a valve to flow cool air from the shuttle to maintain the lab's temperature.
   
• Flight engineers continue to monitor the development and don't expect the glitch to affect the science experiments. All other systems are reportedly operating normally.

Jan 21, 2003

• Ramon speaks with Israeli Prime Minister Ariel Sharon and other dignitaries in Jerusalem. He captures never-before-photographed lightning phenomena, known as "sprites" and "elves," in the extreme upper atmosphere.
   
• For other experiments, commander Husband steers Columbia with its on-board rockets to aim payload bay-mounted instruments to study ozone in the upper atmosphere and another experiment that studies the solar constant.

03:39pm CST

• The Blue Team awakes to "The Wedding Song" by Paul Stookey, uplinked from Mission Control especially for shuttle pilot McCool.
   
• The SPACEHAB's dehumidifiers remain off due to problems and flight engineers continue to seek other cooling options.

Jan 22, 2003

• Engineers finish analysis and submit reports. Computer models predict that worst-case scenarios would not have done damage "sufficient to cause a catastrophic event nor (affect) the flying qualities of the vehicle."
   
• The Columbia crew members beam down video views of the insects, spiders, fish, bees and silkworms that are part of the biology experiments designed by students in six countries.

03:09pm CST

• At the request of astronaut Anderson's children, Mission Control wakes the Blue Team by playing "Kahuna Matata" by the musical group Baja Men.
   
• Mission Control reports cooling and humidity control of the Spacehab module is being effectively managed through minor adjustments.

Jan 23, 2003

• Final engineering reports submitted. First set of follow-up reports submitted to mission managers.
   
• Both teams continue their research work, including further experiments on the nature of fire in space.
   
• Commander Husband, leader of the Red Team, and pilot McCool, leader of the Blue Team, adjust Columbia's attitude relative to the Earth to support the different requirements of experiments.
   
• In the afternoon, Blue Team's wake-up call is "Burning Down the House" by the Talking Heads.

Jan 24, 2003

05:00am CST

• The Red Team conducts experiments involving flame balls as well as human physiology experiments.
   
• In an astro-culture experiment, the last of six samples of essential oils from rose and rice flowers are harvested. Eventually, results from the experiment could lead to in new perfume fragrances.

02:30pm CST

• The Blue Team wakes to "Hotel California," performed by members of McCool's family. They conduct experiments to study how sandy soil full of water behaves under pressure.

Jan 25, 2003

01:00am CST

• After their shift ends, Blue Team crew members conduct interviews with reporters from BET, WTKR-TV in Norfolk, Va., and KNSD-TV in San Diego, CA.

11:30am CST

• Video, narrated by Ramon, is sent to Mission Control showing various experiment operations conducted by both Red and Blue teams. Commander Husband maneuvers Columbia as required for any scientific activities.
  
  Mission specialist Clark completes experiments dealing with bone cells in microgravity and also continues work on the Bioreactor Demonstration System, which is growing prostate cancer tissues to learn how the cancer spreads into  bones and aid in the development of future treatment methods.

02:39 p.m. ET

• Blue Team is awakened to the sounds of "I Say a Little Prayer for You" sung by Dionne Warwick. The song was played for Anderson at his wife's request.

Jan 26, 2003

• The crew sends digital video of the Middle East with breathtaking views of Israel, the Red Sea and the Sinai Peninsula. The video also contained scenes of life and work on orbit involving the seven astronauts. Columbia's systems continue to function perfectly as the shuttle orbits at an altitude of about 180 statute miles.
   
• The Red Team conducts more experiments involving the study of flames in space in a the Combustion Module in the Spacehab.
   
• The crew monitors a lab module containing a half-dozen student-developed experiments ranging from the study of Australian spiders to the analysis of space flight's effects on carpenter bees from Liechtenstein. In the module, fish hatch in an aquatic facility and a silk moth emerges from its cocoon.
   
• More investigations are conducted into the effect of dust storms on the atmosphere with multispectral cameras in Columbia's cargo bay.

Jan 27, 2003

• Final set of follow-up reports submitted to mission managers.

11:30am CST

• The Red Team — Husband, Chawla, Clark and Ramon — take time out from microgravity experimentation to chat with the three astronauts aboard the International Space Station. The space station was some 240 miles above southern Russia while the shuttle was over northern Brazil.

02:39pm CST

• The Blue Team wakes up to the sounds of "Slow Boat to Rio" by Earl Klugh. After a half a day of rest, they resume research activities concentrating on the Mediterranean Israeli Dust Experiment, which the day before captured its first observations of dust over the Atlantic.
  
  Astronauts complete the Structures of Flame Balls experiment, which looked at ways of improving engine combustion efficiency. A total of 55 flame balls are ignited, including the weakest and leanest flames ever burned. The longest-lived flame burned in space for 81 minutes, part of a total burn time for all flames of 6 ¼ hours.

Jan 28, 2003

• An internal NASA Mission Evaluation report gave an engineering team's analysis of the range of possible damage due to foam impact on the wing. The report gave several possible damage assessments, with the worst case indicating "possible localized structural damage, but no burn through, and no safety issue.
   
• The Red Team enjoys some time off from experiments in the morning. Clark retrieves samples associated with the Bioreactor Demonstration System, which has grown a bone and prostate cancer tumor tissue sample as large as a golf ball - the largest grown in space to date.

2:00pm CST

• Chawla and Husband send video of the MIST experiment equipment and a leaky combustion chamber to engineers at Mission Control. The chamber provides control, containment, diagnostics and communications for fire-related experiments and worked flawlessly in two previous combustion experiments, but failed its initial leak checks when MIST was installed a day earlier.

2:39pm CST

• The Blue Team, or evening shift, wakes up to the Beach Boys singing "I Get Around." They later resume tests of their breathing, hearts and muscle associated with Advanced Respiratory Monitoring System.

4:00pm CST

• Chawla finishes repairs and reports back to Mission Control good leak checks to the combustion chamber.

Jan 29, 2003

2:39pm CST

• Blue Team members Anderson, McCool and Brown wake up to the sounds of John Lennon's "Imagine."
   
• McCool and Ramon remark how from their vantage point in space, Earth has no boundaries. "The world looks marvelous from up here, so peaceful, so wonderful and so fragile," Ramon said. Both crew members express. in English and Hebrew, their hopes for peace in the world.
   
• "The science we're doing here is great and it's fantastic," says Anderson. "It's leading edge."
   
• The astronauts take a break from their round-the-clock work and conduct a traditional in-orbit news conference to answer questions from reporters on Earth.

Jan 30, 2003

• Command Husband examines the floor of Spacehab module for water from a balky air-conditioner. He reports to Mission Control that he didn't find any moisture, which could endanger the module during its scheduled Saturday landing, but he covers several holes as a precaution.
   
• Commander Husband and flight engineer Chawla take turns at simulated shuttle landings using an on-board computer-based training system called PILOT. Pilot McCool, the Blue Team leader, practices the landings overnight.
   
• Most of the mission's 80 scientific experiments have been concluded. The crew wraps up the last of the studies, including MIST, an experiment to study how mist of water instead of dangerous Halon gas may be used to put out fires.

Jan 31, 2003

• Husband, McCool and Chawla activate one of the shuttle's three auxiliary power units and begin a standard pre-landing test and inspection of Columbia's flight control surfaces. Everything appears to be normal.
   
• The flight crew test-fires Columbia's on-board "reaction control jets" - the chemical rockets that will slow the shuttle and maneuver the spacecraft out of orbit for landing on 2/1/03.
   
• Israeli astronaut Ramon completes some final experiments, including studying electrical activity in thunderstorms.
   
• The crew stows away gear and deactivates experiments in preparation for the next day's landing attempts. The first "window" of opportunity would occur at 7:15am CST.

Feb 1, 2003

07:08:12am CST

• CAPCOM: “You are go for burn.”

07:08:22am CST

• Columbia (CDR Rick Husband): “OK, we copy a go for the burn right now.”

07:10:39am CST

• [APU-2 startup.]

07:12:34am CST

• [Acquisition of signal by NASA's TDRS-West communications satellite.]

07:15:30am CST

• [Deorbit ignition. Change in velocity: 176 mph; Burn duration: two minutes and 38 seconds. Location (latitude/longitude in minutes:seconds): 33:35 S/98:10 E; altitude: 175.95 statute miles. Velocity: 17,319.7 mph.]

07:18:08am CST

• [Deorbit burn is completed. For the next 26 minutes or so, Columbia continues on a free fall descent toward the discernible atmosphere.]

07:26:09am CST

• [Forward reaction control system propellant dump begins.]

07:27:12am CST

• [FRCS dump complete.]

07:31:25am CST

• [APU-1 startup. Entry interface minus 13 minutes.]

07:31:27am CST

• [This is the start point of the MCC Flight Loop Audio file posted on InsideKSC.com. It is noted here as a reference point for researchers using this section of the FAQ in comparison with the actual audio file.]

07:31:29am CST

• [APU-3 startup.]

07:31:57am CST

• [APU-1 at normal operating pressure.]

07:31:59am CST

• [APU-2 at normal operating pressure.]

07:32:01am CST

• [APU-3 at normal operating pressure.]

07:32:29am CST

• [Shuttle main engine stow sequence begins.]

07:32:31am CST

• Columbia: "Houston, here comes SSME HYD Repress."

07:32:34am CST

• Flight: "MMACS & GNC, you ready?"

07:32:36am CST

• MMACS: "Flight, we're ready."

07:32:37am CST

• GNC: "GNC is Go."

07:32:43am CST

• Columbia: "Copy no deltas."

["No deltas" means the crew understands that there are no further changes to the procedure they are about to perform.]

07:34am CST

• [Approximate start of ICOM videotape shot inside of crew cabin]

07:34:15am CST

• Flight: "FDO, Flight."

07:34:17am CST

• FDO: "Go ahead, Flight"

07:34:18am CST

• Flight: "Did we get another balloon launched?"

[This is referring to a weather balloon launched from KSC. It gathers data about wind speed, air density, and temperature as it rises.]

07:34:19am CST

• FDO: "Yes sir. It's going to be a ten minute delay, basically, in receipt of the data here. That's our estimate."

07:34:24am CST

• Flight: "What's our new time to get the data. time to get, time for me to have a DDS in my hand?"

[DDS (Descent Design System) is a program that evaluates the environment using balloon data to help FDO determine if there are any density shears, which end of the runway to use, how far down the runway they'll touch down, etc.]

07:34:32am CST

• FDO: "It, uh, we'll call it ten til, Flight, local here, another 15 minutes."

07:34:41am CST

• Flight: "OK."

07:34:42am CST

• FDO : "Um, all of this data will be in, if, assuming it goes to, uh, the correct altitude of 10K, we'll, we'll definitely have this before 10, Mach 10, Flight."

07:34:52am CST

• Flight: "OK."

07:34:54am CST

• CAPCOM: "Richard, can you do anything with the balloon that was lost for the 6000 below data?"

07:34:58am CST

• FDO: "They're working that. There might be a data gap but, uh, that might make our data a little suspect."

07:35:05am CST

• Flight: "We won't throw it away, it's just not complete."

07:35:09am CST

• MMACS: "Flight, MMACS."

07:35:11am CST

• Flight: "Go."

07:35:12am CST

• MMACS: "Good SSME HYD repress, and HYD fluid thermal conditioning is not required."

[The crew has completed the SSME Hydraulic Repress procedure. The SSME hydraulic lines are re-pressurized so that the engine nozzles can "parked" after landing in a "rain-drain" position that prevents rainwater from collecting in them - it's a standard action on every entry.]

[Hydraulic Fluid Thermal Conditioning is optional at MCC's call, based on a number of factors including whether or not the crew did the FCS Checkout the previous day. It's usually not required.]

07:35:15am CST

• Flight: "Thank you."

07:35:20am CST

• Unk: "Ok."

07:35:36am CST

• CAPCOM: "Columbia, Houston. the HYD fluid thermal conditioning will not be required today. We'll meet you on the cards."

["The cards" refers to the Entry Maneuvers Cue Card. After they transition to Major Mode 304, the crew doesn't work procedures from  the checklist (book), they use stuff that's printed on a cue card velcroed to the forward panels.]

07:35:46am CST

• Columbia: "Copy Houston. HYD Fluid thermal conditioning not required, and we copy going to the cards."

07:35:53am CST

• CAPCOM: "And Rick, don't want to lead you astray, and don't forget about the stuff on page 3-44."

07:36:04am CST

• Columbia: "Right we're checking that. We've got the flight controller power on. We're working through the rest of it as well. Thanks."

07:36:08am CST

• CAPCOM: "Sounds good."

07:36:12am CST

• GNC: "Flight, GNC. We see good controller config on 3-44. There were a couple of items that hadn't been completed yet prior to MM304,  including the Flight Controller Power switches as called out on page 3-44. They're still a few minutes away from getting there, so it's just a reminder that's the last step."

07:36:25am CST

• Flight: "GNC I missed your last call, I'm sorry. Go ahead."

07:36:27am CST

• GNC: "I'm just saying we see a good controller config on page 3-44."

07:36:35am CST

• Flight: "OK, thank you."

07:36:36am CST

• Flight: "Folks, I'm going to the entry maneuvers cue cards."

07:36:45am CST

• GNC: "Flight, GNC - they accidentally downmoded to inertial. They're back in auto now."

[Either the PLT or CDR accidentally bumped the stick, which the flight control system interprets as the crew taking manual control from the autopilot. The FCS downmodes from Auto to Inertial. The crew saw that they did this, and went back to Auto.]

07:36:50am CST

• GNC: "Flight, GNC - they accidentally downmoded to inertial. They're back in auto now."

07:37:38am CST

• GNC: "Flight, GNC."

07:37:40am CST

• Flight: "Go ahead."

07:37:41am CST

• GNC: "We'd like another ITEM 27. They, uh, got a few degrees out of attitude here."

["ITEM 27" on the crew's display has the autopilot maneuver back to the appropriate attitude. Since they were in manual for a bit, they got slightly out of attitude. Executing ITEM 27 maneuvers them back.]

07:37:44am CST

• Flight: "OK we saw `em get back to auto, Scorch, we'd like to 27."

["Scorch" is CAPCOM Charlie Hobaugh's nickname.]

07:37:52am CST

• CAPCOM: "Columbia, Houston for Rick. We'll take another ITEM 27, please."

07:38:06am CST

• Columbia: "And thanks for that Houston, we'll give you ITEM 27. We bumped the stick earlier."

07:38:11am CST

• CAPCOM: "Not a problem, Rick."

07:38:33am CST

• GNC: "Flight, GNC - they have a nice EI-5 attitude at this time."

["They have a nice EI-5 attitude" means that they're coming up on 5 minutes until Entry Interface (EI). The shuttle would be pitched up at 40 degrees.]

07:38:36am CST

• Flight: "Good job, thanks."

07:39:09am CST

• [Entry interface minus five minutes (OPS-304 PRO).]

07:39:11am CST

• Speedbrake close; rudder commanded to zero degrees.

07:39:17am CST

• Columbia: "OK and Houston, we'll get the 304 at 5 minutes."
  
  ["The 304" is the transition to Major Mode 304, which is the entry flight software. Prior to this, they were in the Major Mode 303 (Deorbit burn/coast) part of software.]

07:39:21am CST

• DPS: "We're go."

07:39:22am CST

• Unk: "Go ahead."

07:39:23am CST

•   Flight: "We are ready."

[DPS telling Flight that she's ready for the crew to transition the software to the new mode.]

07:39:25am CST

• CAPCOM: "Rick, we're ready for ops 304."

07:39:36am CST

• DPS: "OPS 304."
  
  [DPS has now seen the crew enter the command into the computer, which they do by typing "[OPS] 304 [PRO]" on the computer keyboard.]

07:41:35am CST

• STS-Tape: CDR Rick Husband: "Two minutes to entry interface."

07:41:39am CST

• <Mike keyed>

07:41:43am CST

• STS-Tape: Laurel Clark: "I know about the line cable, Willie, I didn't understand your question. You don't want the camera back, right?"

07:41:51am CST

• STS-Tape: Pilot William "Willie" McCool: "I do not want the camera back. "
   
• STS-Tape: Husband: "He's got one mounted in his HUD already."
   
• STS-Tape: Clark: "OK. Yep, yep, yep. Yep, Replug."

[Note that some of the chatter on the videotape happens in rapid succession. Individual times will be noted for each statement where applicable.]

07:41:54am CST

• MCC-Commentator: "This is Mission Control, Houston. Columbia's altitude is now 90 miles above the Pacific Ocean to the north of the Hawaiian islands, about two minutes away from entering the Earth's atmosphere. All activities continuing to go smoothly en-route toward a touchdown at the Kennedy Space Center at 8:16am CST time."

07:41:58am CST

• STS-Tape: McCool: "Replug, that's all you've gotta do."

07:42:08am CST

• STS-Tape: McCool: "When do we start moving our head around, Rick? When we start getting a little bit of Gs?"
   
• STS-Tape: Husband: "A little bit of Gs, yeah."

07:42:29am CST

• STS-Tape: Clark (operating a video camera): "KC, can you look at the camera a second? Look at me."

07:42:35am CST

• STS-Tape: Flight engineer Kalpana Chawla: "Me?"
   
• STS-Tape: Clark: " Yep. Yeah. What KC?"

07:42:37am CST

• MCC-Commentator: "Columbia is currently targeted toward runway three-three at the Kennedy Space Center, the runway selection continues to be discussed here in Mission Control, however. But for its approach to runway three-three, Columbia will perform a right overhead turn to align with the runway of about 214°s around the heading alignment cylinder, an imaginary cylinder created by the microwave landing system for the shuttle that assists in guiding it for its final approach." 

07:42:38am CST

• STS-Tape: Chawla: "Oh, I just turn towards you, I see what you have there."
   
• STS-Tape: Clark: "Yeah." (laughter)
   
• STS-Tape: Chawla: "OK, Laurel."

07:42:51am CST

• STS-Tape: McCool: "Trash bag, KC, if you've got any."
   
• STS-Tape: Chawla: "We are gray taping, you can just give it to us."

07:42:57am CST

• STS-Tape: McCool: "That's six and a half bags."
   
• STS-Tape: Chawla: "OK, I'm going to have to give this to Laurel when she is done."

07:43:05am CST

• STS-Tape: Chawla: "I'm going to gray tape it behind, I mean (garble) tape it behind the seat, I think this is light enough that it will stay."

07:43:18am CST

• STS-Tape: McCool: "Laurel, you see lots of jets firing."
   
• STS-Tape: Clark: "I'm getting the jets firing, I'm trying to see if I can get an overhead window view yet."

07:43:25am CST

• STS-Tape: Husband: "OK. That's all I can do is three and a half bags out of four. So that'll work. If I can pass that back to you?"

07:43:32am CST

• STS-Tape: Chawla: "Rick, if you could wait just one second, I want to get to my gloves before Gs build, I don't want to get..."
   
• STS-Tape: Husband: "Certainly."
   
• STS-Tape: Chawla: "...two up."
   
• STS-Tape: Husband: "Certainly."

07:43:40am CST

• STS-Tape: Chawla: "Here comes (garble)."

07:43:42am CST

• STS-Tape: Husband: "OK. We're just past EI."
   
• STS-Tape: Clark: "Ok."
   
• STS-Tape: Chawla: "I have both gloves."

07:43:47am CST

• STS-Tape: Clark: "Is that jets firing on the DAP, I guess."
   
• STS-Tape: Chawla: "And Rick, I'll take your bag. And float it aft gently, I've got it."

07:43:58am CST

• STS-Tape: McCool: "That might be some plasma now."
   
• STS-Tape: Clark: "Think so, already?"
   
• STS-Tape: McCool: "Yeah, the jets are not firing right now."
   
• STS-Tape: Clark: "All right, it was quite a (garble), actually."
   
• STS-Tape: McCool: "We see it out the front, also."
   
• STS-Tape: Husband: "That's some plasma."

07:44:09am CST

• [Entry interface: The shuttle falls into the discernible atmosphere at an altitude of 400,000 feet above the Pacific Ocean (Location: 30:47 N/167:37 W); velocity: 16,774.2 mph; range to touchdown: 5,113 statute miles.]
   
• STS-Tape: Clark: "Copy, and there's some good stuff outside. I'm filming overhead right now."
   
• STS-Tape: McCool: "It's kind of dull."
   
• STS-Tape: Husband: "Oh, it'll be obvious when the time comes."

07:44:18am CST

• STS-Tape: Clark: "Well, Willy, I guess I could give you the camera to put out the front window."
   
• STS-Tape: Husband: "Here, let's, uh, no, let's don't do that."
   
• STS-Tape: Clark: "OK."
   
• STS-Tape: Husband: "Let's just, uh, let's go ahead and make sure you check your suit pressure integrity, too."
   
• STS-Tape: Clark: "All right."

07:44:51am CST

• STS-Tape: Husband: "And comm check on intercom. Put the, uh, visors down. CDR."
   
• STS-Tape: McCool: "PLT."
   
• STS-Tape: Clark: "PS1. (then laughing to correct herself) MS1."
   
• STS-Tape: Chawla: "I don't have my gloves on yet. MS2."
   
• STS-Tape: Husband: "All right, good enough."

07:45:09am CST

• STS-Tape: Clark: "And we're going to leave visors down, though."
   
• STS-Tape: Husband: "Oh, no. I'm just saying just check your suit's..."
   
• STS-Tape: Clark: "OK."
   
• STS-Tape: Husband: ".. pressure."
   
• STS-Tape: Clark: "And then I'm going to go back off. Yeah."
   
• STS-Tape: Husband: "Yeah."

07:45:20am CST

• MCC-Commentator: "Columbia's altitude now 71 statute miles as it enters Earth's atmosphere above the Pacific Ocean en route to the Kennedy Space Center, its speed 17,000 miles per hour."

07:45:20am CST

• STS-Tape: Husband: "That's good enough for (garbled), I'm going to check one other thing."

07:45:32am CST

• STS-Tape: McCool: "Starting to glow a little bit more now, Laurel."
   
• STS-Tape: Husband: "Yeah... OK, all that's worked."

07:45:44am CST

• MCC-Commentator: "Columbia with wings level and nose angled up at about 40° to control heating as it descends into the atmosphere. It's altitude now 68 miles. As Columbia descends into the atmosphere and approaches the continental United States it'll perform the first in a series of four banks it performs as it approaches the Kennedy Space Center. That first bank to the right, then back to the left, then back to the right and then a final bank to the left as it approaches Kennedy and the Shuttle Landing Facility runway. Those designed to dissipate speed for the shuttle as it descends into the atmosphere toward landing."

07:45:49am CST

• STS-Tape: Husband: "It's noisy in there, isn't it?"

07:45:52am CST

• STS-Tape: McCool: "Do see it over my shoulder now, Laurel?"
   
• STS-Tape: Clark: "I was filming, it doesn't show up nearly as much as the back."

07:45:58am CST

• STS-Tape: McCool: "It's going pretty good, now. Ilan, it's really neat, just a bright orange yellow out over the nose, all around the nose."

07:46:09am CST

• FDO: "Flight, FDO."

07:46:10am CST

• STS-Tape: Husband: "Wait until you start seeing the swirl patterns out your left and right windows."
   
• STS-Tape: McCool: "Wow."
   
• STS-Tape: Husband: "Looks like a blast furnace."

07:46:22am CST

• Flight: "Okay, FDO, go ahead."

07:46:25am CST

• FDO: "Um, this dataset is a spliced dataset. This is my backroom's attempt to, uh, get us some data off that first balloon that was broken, and it shows us eleven hundred and sixty feet past the aim point. And we're waiting for our re-released balloon which was just released a few minutes ago."

[This is a prediction that the shuttle will touch down 1160 feet from the end of the runway.]

07:46:30am CST

• MCC-Commentator: "Just under 30 minutes to touchdown for Columbia now, altitude 64 miles."

07:46:31am CST

• STS-Tape: Husband: "Let's see here... look at that."
   
• STS-Tape: McCool: "Yep, we're getting some gees."
   
• STS-Tape: Husband: "Yeah."
   
• STS-Tape: McCool: "I let go of a card, and it falls."

07:46:39am CST

• STS-Tape: McCool: "I got a bit flip here on the accel now."
   
• STS-Tape: Husband: "Yep. Alright, we're at, uh, hundredth of a G."

07:46:45am CST

• Flight: "OK, now, you, we lost the balloon at 6000 feet and did we get it back at some point? Or when you say "it spliced it together" I mean, I don't wanna, I don't know whether I should."

07:46:48am CST

• [Qbar equals 0.5 pounds per square foot.]

07:46:51am CST

• STS-Tape: McCool: "This is amazing, it's really getting, uh, fairly bright out there."

07:46:55am CST

• FDO: "We did not, we did not get any data beneath 6K, I mean, above 6K, excuse me. And we spliced, basically, a previous data set on top of this one to give us a estimate."

[Due to a problem with the first weather balloon, they're launching a second one. In the meantime, they're taking the best data they have (combining the results from two balloons) to get a "best estimate" of the situation.]

07:46:56am CST

• STS-Tape: Husband: "Yep. Yeah, you definitely don't want to be outside now."

07:47:01am CST

• STS-Tape: Chawla: "What, like we did before?"
   
• STS-Tape: (laughter)

07:47:03am CST

• STS-Tape: McCool: "How's it look out the back, Laurel?"
   
• STS-Tape: Husband (responding to Chawla): "Good point."
   
• STS-Tape: Clark: "Uh..."

07:47:09am CST

• Flight: "Now let's see. from where we're releasing the balloons to, which way, are they going out over the water with the wind direction, um, from the surface on up to about 10,000 feet the direction is roughly out of the west, isn't it?"
   
• STS-Tape: Clark(?): "Willie, I can see you in your mirror."
   
• STS-Tape: McCool: "Not yet?"

07:47:14am CST

• STS-Tape: Clark: "Not, not, yeah, now I can."
   
• STS-Tape: McCool: "Now I can see your camera."
   
• STS-Tape: Husband: "OK." 
  
  [Husband is speaking with a tonal emphasis that is interpreted as "ok kids, enough goofing around back there!"]

07:47:19am CST

• STS-Tape: Clark: "Stop playing."

07:47:20am CST

• STS-Tape: Chawla: "I see 22-10. 10-52 is what we were looking for, for..."
   
• STS-Tape: Husband: "OK. 10-16, right? I've got 16 written here."

07:47:25am CST

• FDO: "Yes Flight, they, they are going out the water, out over the water. I would concur with that. We are."

07:47:30am CST

• Flight: "We start out with them far enough away from where our HAC really is, and then they're going the wrong way."

[The Heading Alignment Cylinder (HAC) is an imaginary cylinder that describes the course the shuttle flies as it approaches the runway for landing.]

07:47:32am CST

• STS-Tape: McCool: "Yeah, 22 10 16."
   
• STS-Tape: Chawla: "Yeah, 22 10 16, that's correct. Sorry."

[At this point, the intact portion of ICOM videotape ends. Towards the end of this segment, the video was showing signs of degradation. According to NASA, nothing beyond this point was able to be recovered]

07:47:34am CST

• FDO: "I would concur. We are seeing, we are definitely seeing some spatial differences here from the STA and this morning - I would concur with that."

07:47:41am CST

• Flight: "I Agree, and the STA the last dive here, and we're not going to have him do anymore, um, was 1941 with CLOSE."

["CLOSE" is shorthand for the Close-in aimpoint on the runway. STA refers to the Shuttle Training Aircraft, which is used to evaluate landing conditions by landing on the planned runway.]

07:47:50am CST

• MCC-Commentator: "Columbia's course toward Florida will take it across the continental United States, crossing the California coast above the San Francisco bay area and continuing across Sacramento, California, providing a spectacular view for persons in that area of Columbia's descent through the atmosphere. That observation of the shuttle would begin about 5:51am CST Pacific standard time and continue for about four minutes, until about 5:55am CST Pacific time, with the shuttle at an elevation of about 78°."

07:47:51am CST

• FDO: "Um."

07:47:52am CST

• [QBAR=2.0 psf, Elevons & Body Flap Active. Altitude=288,932', Mach=24.67]

07:47:53am CST

• Flight: "He normalized at 1941 with CLOSE. Did I get that right?"

07:47:57am CST

• FDO: "X corrected I heard was 1784. (pause) The X corrected normalized."

["X" represents the distance down the runway that the shuttle will touch down.]

07:48:07am CST

• Flight: "Yup, we're talking about the normalized."

07:48:10am CST

• FDO: "I think the STA performs a correction on top of the normalization to account for. um."

07:48:17am CST

• Flight: "Yeah, you're talking XCN. I was just saying the normalized is 1941."

07:48:19am CST

• FDO: "Yes, Sir."

07:48:19am CST

• MCC-Commentator: "It'll be visible as well through much of the United States' southwest above southern Nevada and northern Arizona and central New Mexico as it continues its descent through the atmosphere, trailing a plasma trail left as it heats the atmosphere around it during its descent."

07:48:19am CST

• FDO: "Yes, Sir."

07:48:22am CST

• Flight: "OK, we got the last balloon data to come yet before we make our decision."

07:48:27am CST

• FDO: "Yes, sir."

07:48:42am CST

• MCC-Commentator: "Columbia's altitude now 54 miles as it continues to descend into the atmosphere, wings level, nose angled up 40 degrees to control heating. Columbia's traveling about 17,000 miles per hour."

07:49:07am CST

• [Closed Loop Guidance Initiate. Altitude=259,978', Mach=24.58.]

07:49:16 a.m. (NEW)

• [Roll jets deactivated. Qbar equals 10 pounds per square foot.]

07:49:26am CST

• [Right roll begins; velocity: 16,706 mph]

07:49:32 a.m. (NEW)

• [Initial roll. Mach 24.51.]

07:49:36am CST

• Guidance: "CLG init."

07:49:39am CST

• Flight: "Copy."

07:50:00am CST

• Guidance: "Rolling right."
  
  [Up to this point, the orbiter has been following what is essentially a pre-planned trajectory through the upper atmosphere. Closed-loop Guidance Init (CLG Init) means that the flight control system will begin actively adjusting the orbiter's path in reaction to external conditions.]

07:50:03am CST

• MCC-Commentator: "Columbia's altitude 48 statute miles as it begins the first in a series of four banks to dissipate speed as it descends into the atmosphere, banking to the right now, a steep bank of 60° and approaching the west coast of the United States. Columbia's speed 16,620 miles per hour, range to touchdown at the Kennedy Space Center runway 3,450 statute miles."

07:50:03am CST

• {Columbia?} {garbled - "D=11", "C11", or ".level"}

07:50:19am CST

• <Mike keyed>

07:50:24am CST

• Guidance: "Flight, Guidance."

[Guidance never repeated his call, so whatever he was looking at must have turned out OK.]

07:50:37am CST

• <Mike keyed>

07:50:53am CST

• [Start of Peak Heating Region. Altitude=243,048', Mach=24.12.]

07:50:56am CST

• MCC-Commentator: "Columbia in almost an 80° bank to the right to dissipate speed, the first of four banks it performs as it approaches Florida to slow down as it descends. Altitude now 47 miles or about 248,000 feet. The shuttle's speed is 16,400 miles per hour."

07:51:00am CST

• [All systems appear to be functioning normally. Up to this point, there have been no indications of anything amiss as Columbia plunges through the atmosphere.]

07:51:02am CST

• <Mike keyed>

07:51:19am CST

• [NASA’s Timeline Rev 14 says “Remote sensors indicate off-nominal external event - earliest known event” but does not say specifically what the off-nominal event was.]
   
• [Based on the STS-107 Accident Investigation Master Timeline (Baselined), Revision 14, dated 02/27/03 6:00 pm CST, this is the first indication that anything abnormal is happening to the orbiter. Over the next eight minutes or so, telemetry will indicate a series of sensor failures and elevated temperatures in Columbia's left main landing gear wheel well and along the left side of the fuselage above the left wing.]
   
• [It's important to note that the temperature rises in the various systems were seen only in retrospect, looking at the data in hindsight with the knowledge that something was going to happen. While abnormal, the temperatures by themselves were not cause for alarm, and in fact did not trip any alarms.]

07:51:26am CST

• MCC-Commentator: "Aboard the shuttle on the flight deck are shuttle commander Rick Husband and pilot Willie McCool, flight engineer Kalpana Chawla and mission specialist Laurel Clark. On the lower deck of the shuttle for entry are payload commander Mike Anderson, mission specialist David Brown and payload specialist, from the Israel space agency, Ilan Ramon."

07:51:45am CST

• [RCS jets L2L and L3L (on the left side of the orbiter) fire.]

07:51:46am CST

• [Inertial sideslip angle (Beta) goes and stays Negative until LOS. While the magnitude of the observed Beta is not outside the flight history (similarly seen on STS-41G & STS-42), the almost linear negative ramp prior to the first roll reversal is not consistent with other flights reviewed.  This is consistent with a negative rolling and yawing torque on the vehicle.]

07:52:05am CST

• [Delta yawing moment coefficient only (as compared to nominal aero).  Derived by analysis. This is the first clear indication of off-nominal aero increments.]

07:52:06am CST

• MCC-Commentator: "Columbia approaching the Coast of California now, it is predicted to cross the coast and be visible in the San Francisco area about 5:51am CST time, uh, Pacific standard time rather, and pass almost directly overhead of Sacramento, California. It actually crosses the California coast just to the north of the San Francisco area."

07:52:08am CST

• [RCS jets R2R and R3R fire between now and 07:52:15. Exact time unknown due to typical entry data dropouts.]

07:52:17am CST

• [Left Main Gear (LMG) Brake Line Temp D (located on wheel well inboard sidewall aft of the switching valves) off-nominal rise at 2 deg/min. Sensor location: Near the rear of the main landing gear wheel well directly under the fuselage.  Altitude=236,791', Mach=23.58. Columbia is now over the Pacific Ocean, approx 300 miles West of California coastline.]

07:52:24am CST

• [RCS jets R2R and R3R fire between now and 07:52:32. Exact time unknown due to typical entry data dropouts.]

07:52:29am CST

• <Mike keyed>

07:52:32am CST

• [Supply H2O Dump Nozzle Temps A & B show temporary increase in rise rate for 15 sec, then return to normal rise rate. Similarly, the Vacuum Vent Nozzle Temp also shows a temporary increase in rise rate, lasting 23 seconds. Unknown if these are significant, but they were not observed on previous flights.]

07:52:35am CST

• <Mike keyed>

07:52:41am CST

• [Left Main Gear Brake Line Temp A start of off-nominal rise at 6 deg/min. Sensor location: Mid section of the landing gear wheel well, on the strut near the wheels, facing the door. Sensor A is about a half inch from Sensor B. Altitude=234,928', Mach=23.40. ]
   

• [Left Main Gear Brake Line Temp C Start of off-nominal rise at 5 deg/min. Sensor location: Mid to rear section of the landing gear wheel well, at the top of the strut, in front of Sensor D.]

07:52:47am CST

• [Supply water dump nozzle temperature sensors A and B return to normal rise rate.]

07:52:48am CST

• <Mike keyed>

07:52:48am CST

• [Left Main Gear brake line temperature C sensor sees a 5°/min increase. Sensor location: Toward rear of the landing gear wheel well in front of temp sensor D. ]

07:52:53am CST

• MCC-Commentator: "Columbia is on target for runway three-three at the Kennedy Space Center Shuttle Landing Facility runway."

07:52:55am CST

• Vacuum vent temperature sensor returns to normal rise rate.

07:52:56am CST

• [Left Inboard Elevon Lower Skin Temperature sensor start of off-nominal trend downwards.]

07:52:59am CST

• [Left Inboard Elevon Lower Skin Temperature sensor goes off scale low (OSL). Sensor location: In the middle of the lower side of the left inboard elevon. Sensor cable routing adjacent to left side of the main landing gear wheel well. Altitude=233,618', Mach=23.25.]
  
  [When a sensor goes from being normal to OSL in a step function, one of two things has occurred: either something happened to prevent the signal from getting from the sensor to the computer via the databus (this happens from time to time, and is typically caused by a wire break somewhere along the way), or a signal conditioner has failed (this converts the voltage as output by the sensor into a usable parameter like temperature or pressure). However, both of these parameters don't have any signal conditioner  in common so there wasn't a single event that caused both sensors to fail.]
  
  The OSL failures occur amidst a 20-30° (11-17° C) rise in the left hand bondline and strut temperatures over a five-minute period near the left wheel well of the orbiter. Note that data lines for the sensors that record these measurements are all routed through the left landing gear wheel well.]

07:53:00am CST

• [Columbia continues to fly over California, at an altitude of about 220,000' (67 km) traveling 21 times the speed of sound.]
  
  MCC-Commentator: "The subject of runway selection has been discussed in Mission Control, it continues to be discussed some, but in the meanwhile at present the original targeting for Columbia is toward runway three-three..."

07:53:01am CST

• [Start of steady negative growth in roll moment, derived by analysis. This is the first clear indication of off-nominal rolling moment increment.]

7:53:02am CST

• [Hydraulic 1 Left Inboard Elevon Actuator Return Line Temp - Start of Off-Nominal Trend - Temp Trending Down. Altitude=233,457', Mach=23.23.]
  
  [Hydraulic 3 Left Outboard Elevon Return Line Temp - Start of Off-nominal Trend - Temp Trending Down. Sensor location: Outboard tip of the left wing, just in front of the outboard elevon.]
  
  [This sensor measures the temperature of the hydraulic fluid used to move the elevon. Sensor cable routing adjacent to left side of main landing gear wheel well. Temperatures trending downwards is thought to be evidence of damage to the wires carrying the signal, not an actual temperature drop.]

07:53:10am CST

• [Hydraulic 3 Left Outboard Elevon Actuator Return Line Temp goes OSL. Altitude=232,864', Mach=23.17]
  
  MCC-Commentator: "... and as it approaches runway three-three, it will perform a right overhead 212° turn to align with that runway around the heading alignment cylinder, an imaginary cylinder created by the microwave scan beam landing system at the shuttle runway that assists in the shuttle's guidance toward its final approach to the runway."

07:53:11am CST

• [Hydraulic 1 Left Inboard Elevon Actuator Return Line Temp goes OSL. Sensor location: Just in front of the inboard elevon. Sensor cable routing adjacent to left side of main landing gear wheel well. Altitude=232,793; Mach: 23.16 .]

07:53:24am CST

• [Angle of attack modulation active.]

07:53:26am CST

• [Columbia crosses the coast of California, directly over the town of Gualala. Altitude=231,600', Mach=23.0.]

07:53:30am CST

• MCC-Commentator: "Shuttle's altitude now 45 miles, speed 15,800 miles per hour, continuing in a right bank with wings angles 70°, the first of four banks it performs to dissipate speed as it approaches landing."

07:53:31am CST

• [Hydraulic 1 Left Outboard Elevon Actuator Return Line Temp goes OSL. Sensor location: Outboard tip of the left wing, just in front of the outboard elevon. This sensor measures the temperature of the hydraulic fluid used to move the elevon. Sensor cable routing adjacent to left side of main landing gear wheel well. Altitude=231.304', Mach=23.0.]

07:53:34am CST

• [Hydraulic 2 Left Inboard Elevon Actuator Return Line Temp goes OSL. Sensor location: Just in front of the inboard elevon. Sensor cable routing adjacent to left side of main landing gear wheel well. Altitude=230,915; Mach 22.95.]
   
• [Third indication of re-entry heating with nominal rise in three center line bond temperature sensors (mid fuselage bottom port bondline temps x620, x777 and forward fuselage lower skin bottom center line).]

07:53:44am CST

• MCC-Commentator: "Columbia crossing the California coast, again, just to the north of the San Francisco area. It's course will take it across Sacramento, California."

[Debris #1 - First report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. No evidence of RCS jet firings. Location of observer not specified. Columbia is north of Winters, CA, west of Sacramento, at an altitude of 230,348 ft, traveling Mach 22.88.]

07:53:45am CST

• [Debris #2 - Second report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. No evidence of RCS jet firings.  Location of observer not specified.]

07:53:46am CST

• [Left Main Gear Brake Line Temp A - Start of off-nominal Trend - Temp Rise Rate change from 1.4 F/min to 5 F/min and increasing to loss of signal. Altitude=230,203', Mach=22.86.]

07:53:52am CST

• [Columbia passes directly overhead downtown Sacramento.]

07:53:54am CST

• [Debris #3 - Third report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. Event is followed by a momentary brightening of the plasma trail. No evidence of RCS jet firings. Location of observer not specified. Altitude=229,621', Mach=22.79.]

07:54:00am CST

• [Debris #4 - Fourth report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. No evidence of RCS jet firings.  Location of observer not specified. Altitude=229,113; Mach: 22.73.]

07:54:07am CST

• [Debris #5 - Fifth report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. No evidence of RCS jet firings.  Location of observer not specified. Altitude=228,817', Mach=22.69.]
   

• [Amateur video taken from atop Mt. Hamilton, CA, appears to show separation of small objects from Columbia, seen just aft of the orbiter envelope. It is unknown at this time which of the first five events this video corresponds with.]

07:54:10am CST

• [Left Main Gear brake line temperature B sensor sees unusual 6°/min rise. Sensor location: Middle of landing gear door wheel well. Altitude=228,460', Mach=22.64.]

07:54:20am CST

• [Start of slow aileron trim change - time is approximate +/- 10 sec]

07:54:22am CST

• [Mid Fuselage Left Bond Line Temp at X1215 off-nominal rise at 7.6 deg F/min; normal is 1 deg F/min. Sensor location: On the left side of the fuselage above the wing just behind the landing gear wheel well. Altitude=227,560', Mach=22.52.]
  
  [This reading is unusual because it is above the wing. By comparison, on the right-hand side of the vehicle, in the same location but opposite on the right-hand side showed a nominal 15° F (8° C) rise over the same period of time. Additional telemetry showed that just inside the fuselage, in the payload bay, the cryo tank temperatures were nominal.]
  
  [Aft Fuselage Sidewall Temp at x1410 off-nominal rise at 5.5 deg F/min; normal is 2.7 deg F/min]
  
  MMACS: "Flight, MMACS."

07:54:24am CST

• [Left Main Gear Strut Actuator Temp off-nominal rise at 7 deg/min. Sensor location: Middle of wheel well, near the back wall of the box. Altitude=227,437', Mach=22.51.]

07:54:25am CST

•   Flight: "Go ahead, MMACS."
   
• [Columbia crosses the California/Nevada border east of Bridgeport, CA, northeast of Yosemite National Park. Altitude=227,400' at Mach: 22.5]

07:54:26am CST

• MMACS: "FYI, I've just lost four separate, uh, temperature transducers on the left side of the vehicle, hydraulic return temperatures. Two of them on system 1, and 1 on each of systems 2 and 3."
  
  [MMACS saw the four hydraulic sensors go Off Scale Low (OSL). After the first two, he would be discussing it with his back room and with INCO's back room, trying to figure out if there was any commonality between them. Then 20 seconds later two more went out in quick succession and MMACS quickly called Flight.]

  [Columbia crosses the California/Nevada border east of Bridgeport, CA, northeast of Yosemite National Park.]

07:54:33am CST

• [Columbia is 226,894 ft above the desert in western Nevada, northwest of the town of Basalt, flying at Mach 22.43]

[Flash #1 - Jay Lawson, a volunteer at the Fleischmann Planetarium at the University of Nevada, Reno, videotapes something breaking loose from Columbia, creating a second contrail and slowly falling behind the orbiter. On the video, the shuttle approaches from the right toward the image of the planet Venus, shining in the background center-screen. A flare arises from the shuttle, brightening the orbiter’s envelope for 0.3 seconds, and the craft starts to leave a trail behind it, just before it passes in front of Venus. This flare corresponds exactly with RCS jets R2R and R3R firings.]

[Lawson's video is now online in Quicktime format at the following locations:

For dial-up connections

http://www.rgj.com//news/files/2003/02/01/21411.mov

For broadband connections

http://www.rgj.com//news/files/2003/02/01/21413.mov

Note that you will need either the Quicktime player or a browser plugin to view these clips.]

07:54:35am CST

• [Debris #6 - Very bright debris observed leaving the orbiter, seen just aft of the orbiter envelope. Location of observer not specified. Altitude=226,748', Mach=22.41.]

  [Debris events 6 and 14 (coming up at 07:55:58) are visually the biggest, brightest events and therefore may indicate the most significant changes to the Orbiter of the western debris events.]

07:54:42am CST

• Flight: "Four HYD return temps?"

07:54:45m CST

• MMACS: "To the left outboard and left inboard elevons."

07:54:49am CST

• Flight: "OK, is there anything common to `em. DSC or MDM or anything. You mean you're telling me you lost them all at
  exactly the same time?"
  
  [A Dedicated Signal Conditioner (DSC) takes the voltage reading from a sensor and converts it into a usable format like temperature, pressure, or flow rate. If the DSC is lost, the parameter will show off-scale low with an "L" next to the reading on the displays in both MCC and Columbia. A Multiplexer-Demultiplexer (MDM) is involved with sending the data to the computers and the downlink. If the MDM is lost, the parameter will show up as Missing with an "M" next to the last valid data on the displays.]

07:54:53am CST

• [Main Landing GearLeft Outboard Wheel Temp - start of off-nominal trend. Altitude=225,610', Mach=22.22.]

07:54:55am CST

• MMACS: "No, not exactly. they were within probably 4 and 5 seconds of each other. The first two went down within a second of each other, then a 20 second pause, then two more in 5 seconds after that."

07:54:59am CST

• Flight: "OK. where are those, where is that instrumentation located?"

07:55:04am CST

• [Debris #7 - Seventh report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. No evidence of RCS jet firings. Location of observer not specified.]

07:55:05am CST

• MMACS: "They're, all four of them are located in the aft part of the left wing, right in front of the elevons, elevon actuators, and there is no commonality."

07:55:12am CST

• [System 3 Left Mail Landing Gear Brake Switching Valve Return Line Temp (FWD) - start of Off- nominal Trend - Temp Increase of 5° per minute. Sensor location: Right side wall of landing gear wheel well, toward rear of box. Altitude=224,546', Mach=22.02.]
   

• [Debris #8 - Eighth report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. Event was followed by momentary brightening of plasma trail. No evidence of RCS jet firings. Location of observer not specified.]

07:55:16am CST

• Flight: "No commonality."

  [While this is going on, MMACS' back room (call sign MECH) is probably talking to INCO's back room (call sign INST) to see if they know anything about these instrumentation problems. MECH would call MMACS and report that there was nothing in common]

07:55:21am CST

• [Drag = 11 fps^2; drag measurement incorporation. Altitude=224,002', Mach: 21.92]

07:55:25am CST

• [Debris #9 - Ninth report of debris observed leaving the Orbiter, seen just aft of the orbiter envelope. Event was followed by multiple secondary plasma trails. No evidence of RCS jet firings. Location of observer not specified.]

07:55:26am CST

• [Debris #10 - Tenth report of debris observed leaving the Orbiter, seen well aft of the orbiter envelope. No evidence of RCS jet firings. Location of observer: Ivins, UT.]

07:55:30am CST

• [GMT approximate. Remote sensors indicate off-nominal external event. Preliminary match to debris shedding seen in video from Ivins, UT (Debris #10).  Strong confidence that this is an off-nominal event.  No evidence of RCS jet firings.]
   

• [Other observers photograph Debris #10.]

07:55:32am CST

• [Columbia crosses the Nevada/Utah border southwest of the Dixie National Forest  Altitude=223,400', Mach: 21.8.]

07:55:34am CST

• MCC-Commentator: "Columbia continuing in a right bank, the wings angled 43°, speed 15,000 miles per hour, altitude 43 miles, 2,090 miles to touchdown at the Kennedy Space Center targeted for runway three-three at Kennedy at present. Crossing the continental United States, now crossing above southern Nevada to the north of Las Vegas."

07:55:36am CST

• Debris #11 - Eleventh report of debris observed leaving the orbiter, seen well aft of the orbiter envelope. No evidence of RCS jet firings. Location of observer not specified.] 

07:55:41am CST

• [Mid Fuselage Port (left) Sill Longeron Temp at x1215 - start of off-nominal trend - from 0 deg F/min to 2.6 deg F/min]

07:55:45am CST

• [Debris #12 - Twelfth report of debris observed leaving the orbiter, seen well aft of the orbiter envelope. No evidence of RCS jet firings. Location of observer not specified.]
   

• [Amateur video taken from Wupatki National Monument, 25 mi north of Flagstaff, AZ, reportedly shows separation of debris. According to one calculation, at that time the Columbia was North-Northwest of Flagstaff, just north of the Utah border, ~40 miles over the small town of Kanab, UT. The orbiter was over Kanab at 07:55:53am.]
   

• [Debris #13 - Thirteenth report of debris observed leaving the orbiter, seen well aft of the orbiter envelope. Event was followed by momentary brightening of plasma trail adjacent to debris. No evidence of RCS jet firings. Location of observer not specified.]

07:55:49am CST

• [Columbia moves into “orbital sunrise”, moving from the Earth’s shadow into the sunlight, just north of the Utah/Arizona border.]

07:55:52am CST

• <Mike keyed>

07:55:53am CST

• <Mike keyed>

07:55:55am CST

• [Columbia crosses the Utah/Arizona border, east of a line connecting the border towns of Kanab, UT and Fredonia, AZ. Altitude=222,100', Mach: 21.5]

07:55:58am CST

• Flight: "MMACS, tell me again which systems they're for?"
   

• [Debris #14 – Very bright debris observed leaving the orbiter, seen just aft of the orbiter envelope. Seen just aft of Orbiter envelope.  Debris events 6 (at 07:54:35) and 14 are visually the biggest, brightest events and therefore may indicate the most significant changes to the Orbiter of the western debris events. No evidence of RCS jet firings. Location of observer not specified.]

07:56:01am CST

• MMACS: "It's all three hydraulic systems. It's, two of them are to the left outboard elevon, and two of them are to the left inboard."

07:56:02am CST

• [Aerodynamic pressure (Qbar) = 40 psf; Aft RCS Pitch jets deactivated. This is normal. Altitude=221,670; Mach: 21.45.]

07:56:03am CST

• [Left Lower Wing Skin Temp - start of off-nominal trend - temp reading trending down. Potential sensor/wire damage? Altitude=221,612', Mach: 21.44]

07:56:09am CST

• [Debris #15 - Fifteenth report of debris observed leaving the orbiter, seen just aft of the orbiter envelope. Closest RCS jet firings are 8 seconds after this event. Location of observer not specified.]

07:56:10am CST

• Flight: "OK, I got ya."

07:54:16am CST

• [Left main landing gear uplock actuator unlock line temperature sensor sees a rise of 4° per minute. Sensor location: Right side rear of landing gear wheel well.]

• [Hydraulic 1 Left Main Gear Uplock Actuator Unlock Line Temp - Temp rise rate change from 0.7 deg F/min (normal) to 3.9 deg F/min and increasing to LOS. Altitude=220,778', Mach: 21.28.]

07:56:17am CST

• Guidance: "Flight, Guidance. We're processing drag with good residual."

  [This is a routine call. When the shuttle's deceleration reaches 11 ft/sec^2, its computer systems begin calculating the outside air density and comparing it with a standard atmospheric table to estimate altitude. The difference (residual) between this altitude and the value being used by the navigation system is, in this case, good (small enough). The software is doing its job, and the Guidance flight controller doesn't see anything wrong yet.]
   

• [System 3 Left Main Gear Brake Switching Valve Return Line temp (FWD) - Temp Rise rate change from 1.5 deg F/min to 8.8 deg F/min. Altitude=220,778', Mach: 21.28.]

07:56:19am CST

• Flight: "Copy, thank you."

07:56:20am CST

• [Left Main Gear Brake Line Temp C - Temp Rise Rate Change from 1.3 deg F/min to 9.9 deg F/min Altitude=220,488', Mach: 21.23.]

07:56:22am CST

• [Left Main Gear Brake Line Temp B - Temp Rise Rate Change from 2.1 deg F/min to 9.1 deg F/min, increasing to LOS. Altitude=220,374', Mach: 21.21.]

07:56:24am CST

• [Left Upper Wing Skin Temp - Start of Off-nominal Trend - Temp reading trending down (possible sensor/wire damage). Sensor location: Middle of wing, upper and lower surfaces. Sensor cable routing adjacent to left side of main landing gear wheel well.]  

07:56:30am CST

• [1st Roll reversal Initiation, 63 degrees. Columbia is traveling at Altitude=219,820', Mach=21.13] 

07:56:35am CST

• GC: "Flight, GC."

07:56:36am CST

• [Left main landing gear uplock actuator unlock line temperature sensor sees a rise of 4° per minute. Sensor location: Right side rear of landing gear wheel well.]

07:56:37am CST

• Flight: "Go."

07:56:38am CST

• GC: "Your Air-to-Grounds are enabled for the landing count."

07:56:40am CST

• Flight: "Thank you."

07:56:45am CST

• [Columbia crosses the Arizona/New Mexico border, east of a line connecting the border towns of Milkwater, AZ and Crystal, NM. Altitude=219,000', Mach=20.9.]

07:56:46am CST

• MCC-Commentator: "Columbia's course continuing across Arizona and the Arizona and New Mexico border near the four corners area of the United States. Its course will take it almost directly above Alberquerque, New Mexico, it's altitude now 225,000 feet or 42 miles, speed 14,300 miles per hour, 1,785 miles to touchdown at the Kennedy Space Center. 07:56:53am CST."

[System 3 Left Main Gear Strut Actuator Temp - Temp Rise Rate Change from 1.7 deg F/min to 12.9 deg F/min]

07:56:53am CST

• [System 3 Left Main Gear Strut Actuator Temp - Temp Rise Rate Change from 1.7 degF/min to 12.9 degF/min. The temperature stayed at this rate until LOS. Altitude=218,839', Mach=20.80.]

07:56:55am CST

• [1st Roll Reversal Complete. Altitude=218,817', Mach=20.76.]

07:56:58am CST

• [IMU Velocity Increase]. Reflects accelerations imparted during roll reversal.  Same signature observed on STS-109.  Nominal event. Altitude=218,784', Mach=20.74.]

07:57:06am CST

• MCC-Commentator: "It's banking now back to the left, the second in a series of four banks that dissipate speed of the spacecraft as it becomes an aircraft and descends into the atmosphere toward Florida. Wings angled about 75° to the left."

07:57:19am CST

• [Left Main Landing Gear Outboard Tire Pressure 1 - Start of Off-nominal Trend upwards. Altitude=217,757', Mach=20.45.]

07:57:24am CST

• [Left Main Landing Gear Outboard Tire Pressure 2 - Start of Off-nominal Trend upwards. Altitude=217,315', Mach=20.38.]

• Flight: "GNC, Flight."

07:57:25am CST

• GNC: "Flight, GNC."

07:57:28am CST

• Flight: "Everything look good to you? Control and rates and everything is nominal, right?"

• [Left Lower Wing Skin Temp Off Scale Low. Altitude=216,845', Mach=20.31.]

07:57:32am CST

• GNC: "Control has been stable through the rolls that we've done so far Flight, we have good trims, I don't see anything out of the ordinary."

[They are probably picking up some drag, but it's apparently not big enough to call Flight about, probably towards the high end of what they've seen before but still within experience. Any structural damage has not started affecting guidance.]

07:57:41am CST