08:56:49 a.m. - 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 Albuquerque, 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.
08:56:53 a.m. - System 3 left main gear strut actuator temperature sees increase from 1.7 F/min to 12.9 F/min; remains constant through LOS. H=218,839; Mach: 20.80 UPDATE
08:56:55 a.m. - First roll reversal complete. H=218,817; Mach: 20.76
08:56:58 a.m. - Inertial measurement unit (IMU) velocity increase; considered a normal signature due to accelerations imparted by roll reversal. H=218,784; Mach: 20.74 UPDATE
08:57:00 a.m. - Body flap deflected upward 3 degrees; considered nominal. NEW
08:57:11 a.m. - 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 degrees to the left."
08:57:19 a.m. - Main landing gear left outboard tire pressure 1 begins an off-nominal trend (bit flip up). H=217,757; Mach: 20.45 (+35.385-106.785)
08:57:24 a.m. - Main landing gear left outboard tire pressure 2 begins an off-nominal trend (bit flip up). H=217,315; Mach: 20.38 (+35.290-106.481)
08:57:25 a.m. - MCC-FLIGHT: "GNC, FLIGHT."
MCC-GNC: "FLIGHT, GNC."
MCC-FLIGHT: "Everything look good to you, control and rates and everything is nominal, right?"
08:57:28 a.m. - Left lower wing skin temperature drops off-scale low (sensor failure). H=216,845; Mach: 20.31 (+35.215-106.239)
08:57:35 a.m. - MCC-GNC: "Control's 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."
08:57:43 a.m. - Left upper wing skin temperature sensor drops off-scale low. H=215,020; Mach: 20.09
08:57:45 a.m. - MCC-FLIGHT: "OK. And MMACS, FLIGHT?"
MCC-MMACS: "FLIGHT, MMACS."
MCC-FLIGHT: "All other indications for your hydraulic system indications are good."
08:57:53 a.m. - MCC-MMACS: "They're all good. We've had good quantities all the way across."
MCC-FLIGHT: "And the other temps are normal?"
MCC-MMACS: "The other temps are normal, yes sir."
08:57:54 a.m. - System 2 left brake switch valve return temperature (aft) begins seeing an off-nominal temperature increase. H=213,270; mach: 19.91
08:57:59 a.m. - MCC-FLIGHT: "And when you say you lost these, are you saying that they went to zero..."
MCC-MMACS: "All four of them are off-scale low."
MCC-FLIGHT: "... or off-scale low."
MCC-MMACS: "And they were all staggered. They were, like I said, within several seconds of each other."
MCC-FLIGHT: "OK."
08:58:03 a.m. - Start of "sharp" elevon trim increase to counteract increasing aerodynamic drag (timing +/- 10 seconds). H=212,007; Mach: 19.79 UPDATE
08:58:09 a.m. - Substantial increase in calculated rolling and yawing moments. NEW
08:58:16 a.m. - Left main gear brake line temperature sensor D sees a rise rate change from 0.9 F/min to 11.7 F/min (not increasing) to LOS. H=210,304; Mach: 19.55 (+34.287-103.293)
08:58:20 a.m. - Columbia crosses the New Mexico-Texas state line. H=209,000; Mach: 19.5 (+34.2-103.1) NEW
08:58:32 a.m. - Main landing gear left outboard/inboard tire pressure 1 sensors see pressure trending down to off-scale low; main landing gear left outboard wheel temperature begins trending down to off-scale low (timing not exact; follows 7-second loss of signal) UPDATE
08:58:32-22 a.m. - System 2 left brake switching valve return temperature (aft) sees rise from 2.5 F/min to 40 F/min until peak at 8:59:22 a.m. H=208,380; Mach: 19.28 (+33.980-102.325) UPDATE
08:58:36 a.m. - Main landing gear inboard wheel temperature begins trending down to off-scale low. H =207,918; Mach: 19.21 (+33.908-102.099)
08:58:36 a.m. - MCC-Commentator: "Columbia continuing toward Florida, now approaching the New Mexico-Texas border. Altitude 40 miles..."
08:58:38 a.m. - Main landing gear outboard tire pressure 1 sensor drops off-scale low.
08:58:39 a.m. - Main landing gear left outboard wheel temperature goes off-scale low; main landing gear left outboard tire pressure 2 sensor begins trending down to off-scale low. (+33.873-101.987) UPDATE
08:58:40 a.m. - Columbia's backup flight system (BFS) computer displays four tire pressure fault messages on a cockpit display. UPDATE
08:58:40 a.m. - Main landing gear inboard tire pressure 1 sensor drops off-scale low. H=207,370; Mach: 19.13 (+33.837-101.875)
08:58:41 a.m. - Main landing gear left inboard tire pressure 2 sensor stars off-nominal increase, rising about 3.5 psia in 2 seconds. H=207,132; Mach: 19.09
08:58:43 a.m. - Main landing gear inboard tire pressure 2 begins trending down.
08:58:44 a.m. - MCC-FDO: "FLIGHT, FDO."
08:58:48 a.m. - STS-CDR: "And, uh, Hou(ston)..."
08:58:48 a.m. - Main landing gear left inboard wheel temperature and main landing gear inboard tire pressure 2 sensors drop off-scale low. H=206,403; Mach: 18.99
08:58:51 a.m. - MCC-Commentator: "... speed 13,200 miles per hour. Range to touchdown 1,400 miles. The shuttle in a left bank with the wings banked about 57 degrees to horizontal."
08:58:54 a.m. - Main landing gear left outboard tire pressure 2 sensor drops off-scale low. H=205,553; Mach: 18.86
08:58:56 a.m. - Backup flight system computer displays tire pressure fault message (final message). H=205,311; Mach: 18.83 (+33.541-100.931)
08:59:06 a.m. - MCC-FLIGHT: "FDO, FLIGHT."
MCC-FDO: "Uh, we have the balloon. It is being run through DDS (data display system) right now."
08:59:06 a.m. - Left main gear downlocked indication - transferred ON - uplock indicates no change. H=204,336; Mach: 18.86 (+33.370-100.384)
08:59:15 a.m. - MCC-MMACS: "FLIGHT, MMACS."
MCC-FLIGHT: "Go."
08:59:18 a.m. - MCC-MMACS: "We just lost tire pressure on the left outboard and left inboard, both tires."
08:59:22 a.m. - System 2 left brake switching valve return temperature sensor (aft) begins a sharp downward trend to off-scale low.
08:59:23 a.m. - Loss of realtime data in mission control workstations. NEW
08:59:24 a.m. - MCC-CAPCOM: "And Columbia, Houston, we see your tire pressure...
MCC-FLIGHT: "Copy..."
MCC-CAPCOM: "...messages and we did not..."
MCC-FLIGHT: "Is it instrumentation, MMACS? Gotta be..."
MCC-CAPCOM: "...copy your last."
08:59:30.66 a.m. - Start of R2R, R3R yaw jet firing; both jets on at loss of signal to assist elevons in counteracting the increasing aerodynamic drag. H=200,767; Mach: 18.16 (+32.956-99.041)
08:59:30 a.m. - MCC-MMACS: "FLIGHT, MMACS, those are...
08:59:31 a.m. - Maximum observed elevon deflections; Left: -8.11 degrees up; Right: -1.15 degrees up
08:59:31.4 a.m. - Flight control system channel 4 aerosurface position measurements start trending toward their null values. This indicates worsening failures and wiring shorts. NEW
08:59:31.478 a.m. - All flight control system channel 4 bypass valves close (indicate bypass). This is an indication of ASA high-rate data failure. NEW
08:59:31.7 a.m. - Speedbrake channel 4 OI position measurement indicates 19, 20 and 24 degrees open over last three samples prior to loss of signal. Speedbrake should be closed at 0 degrees. No change seen in actuator motion. Signature considered nominal response to bypass valve closing (see above).
08:59:32 a.m. - Maximum observed elevon trim (-2.3 degrees); loss of signal for left mid fuselage bondline temperature sensor at x1215; left aft fuselage sidewall temperature at x1410; left main gear brake line temperatures (A: 172.2 F; B: 154.2 F; C: 104.8 F; D: 88.3 F); left main gear strut actuator temperature (76.3 F); hydraulic system 1 left main gear uplock actuator unlock line temperature (52.2 F); System 2 left brake switch valve return temperature (aft, 62.8 F); system 3 left main gear brake switch valve return line temperature (67.3 F)
08:59:32 a.m. - Columbia is approaching Dallas, Texas. H=200,700; Mach: 18.1 (+32.9-99.0) NEW
08:59:32 a.m. - STS-CDR: "Roger, uh buh (CUTOFF)" (Editor's note: Phonetically, sounded like first syllable of "before" or possibly "both;" he may have been responding to the BFS fault messages for both left-side main landing gear tires) UPDATE
MCC-MMACS: "...also off-scale low."
08:59:32.130 a.m. - Flight control system channel 4 fail flags raised on all aerosurface actuators. NEW
08:59:32.136 a.m. - Last valid data frame accepted by ODRC - OI/BFS/PASS. The backup flight system computer selected the upper right aft quad antenna to communicate with TDRS-West. The pointing angle was off the shuttle's tail at -65 degrees and trending further into blockage; previous experience shows a probable loss of communications at angles greater than -60 degrees. Therefore, the loss of communications experienced here is consider normal and not the result of any failure or attitude change by the orbiter. NEW
08:59:32.195 a.m. - ASA 4 remote power controller and A&C trip indication due to electrical short. NEW
08:59:33.56 a.m. - Backup flight system fault message (1): Flight control system Channel 4 (TDRS-East data). NEW
08:59:33.598 a.m. - Left outboard bypass valve reopens. A "force fight" between channels 1/2/3/4 begins, resulting in a difference of up to 0.5 degrees between left outboard and inboard elevons; indicates a short in the bypass valve. NEW
08:59:33.863 a.m. - PASS flight computers annunciate a fault (1): Flight control system channel 4 (TDRS-East data). NEW
08:59:33.976 a.m. - Master alarm sounds in the cockpit; cause as yet unknown. NEW
08:59:34.518 a.m. - Left outboard "force fight" ends; driver currents go to zero, indicating remote power controller B has tripped; all bypass valves would open. NEW
08:59:34.561 a.m. - Speedbrake force fight begins and continues to LOS; indicates opening of all bypass valves due to RPC B trip. Speedbrake is already at zero. NEW
08:59:35-36 a.m. - Vehicle sideslip changes sign. Just prior to initial LOS at 8:59:32.136, the magnitude of Columbia's negative sideslip start to decrease; Between 8:59:34 and 8:59:37, sideslip grew from -.6 to +.8 degrees. Aerodynamic forces due to sideslip are now reinforcing the drag caused by problems with the left wing. NEW
08:59:36 a.m. - Bank attitude error begins growing. Up until this moment, the flight control system had been able to maintain a bank angle error around 5 degrees by dropping left wing. NEW
08:59:36.8 a.m. - Aerojet DAP (digital autopilot) commands a third RCS jet - R4R - to fire to counteract increasing aerodynamic forces pulling vehicle to the left (yaw down relative to Earth); R4R fires and remains on through 8:59:37.396 a.m. when data is lost for 25 seconds. NEW
08:59:37.3 a.m. - Aerojet DAP orders R1R to begin firing; stays on through LOS at 8:59:37.396 a.m. NEW
08:59:37 a.m. - Last aileron data; rate of change had reached maximum allowed by flight control system. NEW
08:59:37.396 a.m. - Loss of data for 25 seconds. Additional data in this 25-second gap is recovered in computer buffers during a final two second burst of telemetry. NEW
08:59:46.347 a.m. - PASS flight computers generate a "roll reference" fault message. This message is recovered during final two seconds of telemetry in a computer buffer. The timing of this message - 10 seconds after four aft jets began firing - indicates rapid change in lift-to-drag ratio. NEW
08:59:49 a.m. - STATIC.
08:59:52.114 a.m. - PASS fault message: Left RCS leak (data suspect). NEW
08:59:58 a.m. - MCC-INCO: "FLIGHT, INCO."
MCC-FLIGHT: "Go."
MCC-INCO: "Just taking a few hits here. We're right up on top of the tail. Not too bad."
09:00:01.540 a.m. - BFS fault message: Left RCS leak (data suspect). NEW
09:00:01.9 a.m. - BFS fault message: Left RCS leak (timing data suspect). NEW
09:00:02-06 a.m. - Debris A - large piece - seen leaving the orbiter and falling away. NEW
09:00:02.654 a.m. - BFS fault message: Left RCS LJet (data suspect). NEW
09:00:02.660 a.m. - Telemetry resumes for approximately two seconds after a 25-second drop out. Data from this final burst is suspect because of multiple bit errors. Only one data sample was available for many measurements. As a result, some of the following conclusions may be in error. NEW
09:00:0X.XXX a.m. - BFS fault message: SM1 AC VOLTS (exact timing unknown; data suspect). NEW
09:00:03.637 a.m. - PASS fault message: Left RCS PVT (data suspect). NEW
09:00:03.637 a.m. - PASS fault message: Digital autopilot downmode rotational hand controller. Because of software timing issues, this event could have occurred as early as 9:00:01.717 a.m. Data indicates astronaut activation of rotational hand controller (RHC in detent), presumably to take over manual control. But the digital autopilot remained in AUTO through final loss of signal. NEW
09:00:04.826 a.m. - Last downlink frame. NEW
09:00:17-21 a.m. - Debris B observed leaving the orbiter. NEW
09:00:18 a.m. - MCC-FLIGHT: "MMACS, FLIGHT."
09:00:18-22 a.m. - Debris C observed well aft of orbiter. NEW
09:00:21-25 a.m. - Onset of vehicle main body breakup. NEW
MCC-MMACS: "FLIGHT, MMACS."
MCC-FLIGHT: "And there's no commonality between all these tire pressure instrumentations and the hydraulic return instrumentations."
09:00:27 a.m. - MCC-MMACS: "No sir, there's not. We've also lost the nose gear down talkback and the right main gear down talkback."
MCC-FLIGHT: "Nose gear and right main gear down talkbacks?"
MCC-MMACS: "Yes sir."
09:00:30 a.m. - Time-stamped video from Apache helicopters flying near Fort Hood, Texas, shows multiple contrails.
09:00:51 a.m. - MCC-EECOM: "And FLIGHT, EECOM."
MCC-FLIGHT: "EECOM."
MCC-EECOM: "I've got four temperature sensors on the bond line data that are off-scale low."
09:00:53 a.m. - End of peak heating region. NEW
09:01:16 a.m. - MCC-Commentator: "Columbia out of communications at present with mission control as it continues its course toward Florida..."
09:01:29 a.m. - MCC-INCO: "FLIGHT, INCO, I didn't expect, uh, this bad of a hit on comm."
09:01:38 a.m. - MCC-FLIGHT: "GC, how far are we from UHF? Is that two-minute clock good?"
MCC-UNKNOWN: "Affirmative, FLIGHT."
09:02:00 a.m. - MCC-GNC: "FLIGHT, GNC."
MCC-FLIGHT: "Go."
MCC-GNC: "If we have any reason to suspect any sort of controllability issue, I would keep the control cards handy on page four-dash-13."
MCC-FLIGHT: "Copy."
09:02:21 a.m. - MCC-Commentator: "Fourteen minutes to touchdown for Columbia at the Kennedy Space Center. Flight controllers are continuing to stand by to regain communications with the spacecraft..."
09:02:29 a.m. - MCC-FLIGHT: "INCO, we were rolled left last data we had and you were expecting a little bit of ratty comm, but not this long?"
09:02:37 a.m. - MCC-INCO: "That's correct, FLIGHT. I expected it to be a little intermittent. And this is pretty solid right here."
MCC-FLIGHT: "No onboard system config changes right before we lost data?"
MCC-INCO: "That is correct, flight. All looked good."
MCC-FLIGHT: "Still on string two and everything looked good?"
MCC-INCO: "String two looking good."
09:03:03 a.m. - MCC-GC: "Two minutes to MILA."
09:03:12 a.m. - MCC-CAPCOM: "Columbia, Houston, comm check."
09:03:23 a.m. - MCC-FDO: "FLIGHT, FDO."
MCC-FLIGHT: "Go."
MCC-FDO: "Close-end aim point with the one-hour balloon shows us touching down at 1,496, 1,500 feet down the runway. Our crosswind right now is on the left, from the left on the three-three end."
09:03:40 a.m. - MCC-CAPCOM: "Columbia, Houston, UHF comm check."
09:03:45 a.m. - MCC-Commentator: "CAPCOM Charlie Hobaugh calling Columbia on a UHF frequency as it approaches the Merritt Island tracking station range in Florida. Twelve-and-a-half minutes to touchdown, according to clocks in mission control." (listeners hear unease in the voice inflection)
09:03:46 a.m. - MCC-FDO: "FLIGHT, I'd like to stay where we're at."
MCC-FLIGHT: "I copy."
09:03:53 a.m. - MCC-MMACS: "FLIGHT, MMACS."
MCC-FLIGHT: "MMACS?"
MCC-MMACS: "On the tire pressures, we did see them go erratic for a little bit before they went away, so I do believe it's instrumentation."
MCC-FLIGHT: "OK."
09:04:05 a.m. - MCC-CAPCOM: "Columbia, Houston, UHF comm check."
09:04:35 a.m. - MCC-FDO: "FLIGHT, FDO."
MCC-FLIGHT: "Go."
MCC-MALE VOICE: "I know this data's a little late, the one-hour balloon protects us for winds...
09:04:41 a.m. - MCC-CAPCOM: "Columbia, Houston, UHF comm check."
MCC-FDO: "...I think we're in a smaller wind persistence case than that. In other words, we shouldn't expect as big of a change. I'm comfortable with 1,500 feet down the runway."
09:04:54 a.m. - MCC-Commentator: "Flight controllers are standing by for Columbia to move within communications range of the Merritt Island tracking station in Florida to regain communications with Columbia."
09:04:57 a.m. - MCC-GC: "Flight, GC."
MCC-FLIGHT: "Go."
MCC-GC: "MILA not reporting any RF at this time."
MCC-INCO: "FLIGHT, INCO, SPC just should have taken us to STDN low."
MCC-FLIGHT: "OK."
09:05:13 a.m. - MCC-FLIGHT: "FDO, when are you expecting tracking?"
MCC-FDO: "One minute ago, FLIGHT."
09:05:21 a.m. - MCC-Commentator: "Also, flight controllers standing by for tracking data of Columbia that's also received through the Merritt Island tracking station."
09:05:26 a.m. - MCC-CAPCOM: "Columbia, Houston, UHF comm check."
09:05:51 a.m. - MCC-Commentator: "Ten and a half minutes to anticipated touchdown for Columbia." (voice inflection signals uncertainty)
09:06:29 a.m. - MCC-GC: "And FLIGHT, GC, no C-band yet."
MCC-FLIGHT: "Copy."
09:06:56 a.m. - MCC-Commentator: "Flight controllers are still standing by for C-band tracking data from the Merritt Island tracking station of Columbia and UHF communications."
09:07:08 a.m. - MCC-CAPCOM: "Columbia, Houston, UHF comm check."
09:07:22 a.m. - MCC-INCO: "FLIGHT, INCO."
MCC-FLIGHT: "Go."
MCC-INCO: "I could swap strings in the blind."
09:07:36 a.m. - MCC-FLIGHT: "OK, command us over."
MCC-INCO: "In work, FLIGHT."
09:08:07 a.m. - MCC-Commentator: "Eight minutes on the touchdown clock for Columbia, flight controllers continuing to stand by to regain communications with the spacecraft."
09:08:25 a.m. - MCC-INCO: "FLIGHT, INCO, I've commanded string one in the blind."
MCC-FLIGHT: "INCO?"
MCC-INCO: "I've commanded string one in the blind, FLIGHT."
MCC-FLIGHT: "Copy."
09:08:34 a.m. - MCC-Commentator: "Flight controllers standing by for communications through the Merritt Island tracking station, a ground tracking site in Florida."
09:09:27 a.m. - MCC-GC: "And FLIGHT, GC."
MCC-FLIGHT: "Go."
MCC-GC: "MILA's taking one of their antennas off into a search mode."
MCC-FLIGHT: "Copy. FDO, FLIGHT?"
MCC-FDO: "Go ahead, FLIGHT."
MCC-FLIGHT: "Did we get, have we gotten any tracking data?"
MCC-FDO: "We got a blip of tracking data, it was a bad data point, FLIGHT. We do not believe that was the orbiter. We're entering a search pattern with our C-bands at this time. We do not have any valid data at this time."
09:09:29 a.m. - Projected time Columbia's velocity would have dropped to Mach 2.5 had this been a normal approach.
09:09:55 a.m. - MCC-FLIGHT: "OK. Any other trackers that we can go to?"
MCC-FDO: "Let me start talking, FLIGHT, to my navigator."
09:10:07 a.m. - MCC-Commentator: "This is mission control, Houston. Flight controllers are continuing to seek tracking data of Columbia. Touchdown clocks countdown to six minutes to touchdown for the anticipated shutdown, touchdown of Columbia at the Kennedy Space Center runway. Tracking data is being sought through the Merritt Island tracking station located near the Kennedy Space Center in Florida."
09:10:35 a.m. - MCC-Commentator: "Communications with Columbia were lost at about 8 a.m. Central time, about 10 minutes ago."
09:11:38 a.m. - Projected time Columbia's velocity would have dropped below the speed of sound had this been a normal approach.
09:12:34 a.m. - MCC-Commentator: "This is mission control, Houston. Flight controllers are continuing to stand by for communications from Columbia. The last communications with the spacecraft occurred about 8 a.m. Central time as it was above central Texas. Currently seeking communications or tracking data from the spacecraft through C-band radar and ground tracking sites located at the Merritt Island tracking station in Florida."
09:12:39 a.m. - Projected time Columbia would have been banking on the heading alignment cylinder to line up on runway 33 had this been a normal approach.
09:12:40 a.m. - (time approximate) Mission operations representative Phil Engelauf, sitting directly behind Cain, gets a call informing him that video shot by a Dallas TV station shows multiple contrails along Columbia's path. This is the first notification of vehicle breakup in mission control. Engelauf informs astronaut Ellen Ochoa, sitting to his right, and then Cain. The flight director pauses a moment, digesting the news, and then turns back to the flight control team to declare a contingency. NEW
09:12:55 a.m. - MCC-FLIGHT: "GC, FLIGHT. GC, FLIGHT."'
MCC-GC: "FLIGHT, GC."
MCC-FLIGHT: "Lock the doors."
MCC-GC: "Copy."
09:13:17 a.m. - MCC-FLIGHT: "FDO, do you have any tracking?"
MCC-FDO: "No sir."
09:13:43 a.m. - MCC-MOD: "FLIGHT, MOD, on the flight loop."
09:13:51 a.m. - MCC-FDO: "FLIGHT, FDO."
MCC-FLIGHT: "Go."
MCC-FDO: "My C-bands have not acquired anything. We are only in track, uh, acquiring false locks at this time."
09:14:11 a.m. - MCC-FLIGHT: "I copy, FDO."
09:14:26 a.m. - MCC-Commentator: "This is mission control, Houston. Flight controllers continue to seek tracking or communications with Columbia through Merritt Island tracking station. Last communications with Columbia was at 8 a.m. Central time, approximately above Texas as it approached the Kennedy Space Center for its landing. Flight director Leroy Cain is now instructing controllers to get out their contingency procedures and begin to follow those."
09:14:29 a.m. - MCC-FLIGHT: "OK, all flight controllers on the flight loop, we need to kick off the FCOH (Flight Control Operations Handbook) contingency plan procedure, FCOH checklist page 2.8-5."
09:14:52 a.m. - MCC-FLIGHT: "FDO, FLIGHT. ... FDO, FLIGHT."
MCC-FDO: "Go ahead."
MCC-FLIGHT: "Do you have any information or reports from Space Command?"
09:15:04 a.m. - MCC-Commentator: "Flight dynamics officer reports no tracking data from the C-band radar at the Merritt Island tracking station has been reported of any objects."
09:15:50 a.m. - Columbia's scheduled touchdown time on runway 33 at the Kennedy Space Center.
09:17:57 a.m. - MCC-FLIGHT "OK, all flight controllers, on page 9, of the FCOH procedure you need to make sure you step through the actions required in step 20, that's for your workstation logs, display printouts, there's a whole list of data collection items we need to make sure we log through."
09:18:20 a.m. - MCC-Commentator: "This is mission control, Houston. Flight director Leroy Cain is instructing controllers to follow contingency procedures. The last communications with the shuttle Columbia during its descent from orbit were at about 8 a.m. Central time as it was descending through the atmosphere..."
09:18:36 a.m. - MCC-FLIGHT: "And GC, FLIGHT?"
MCC-GC: "FLIGHT, GC."
MCC-FDO: "FDO, FLIGHT
MCC-FLIGHT: "We need to take the equivalent of a command server TSU (Trajectory Server Upgrade) checkpoint..."'
MCC-FDO: "Yes sir."
MCC-GC: "Copy."
MCC-FLIGHT: "We don't have the old DSC (Dynamic Standby Computer) checkpoint but we have the equivalent capability that we need to do."
MCC-GC: "We'll get that done."
09:18:40 a.m. - MCC-Commentator: "...at an altitude of about 207,000 feet en route to the Kennedy Space Center in Florida and a touchdown that was anticipated to occur about two-and-a-half minutes ago. Flight controllers received no further communications with the spacecraft after about 8 a.m. Central time and no further tracking data from the spacecraft was gained from C-band tracking radar at the Merritt Island tracking station in Florida."
09:18:58 a.m. - MCC-FLIGHT: "GC, FLIGHT."
MCC-GC: "FLIGHT, GC."'
MCC-FLIGHT: "You understand how to do the end-of-file log tapes we need...
MCC-GC: "Yes sir."
MCC-FLIGHT: "...in the checklist? OK."
09:19:14 a.m. - MCC-Commentator: "Contingency procedures in effect in mission control require all operators to conserve all their data and logbooks and notes that have been taken, that being instructed by flight director Leroy Cain for controllers to begin following those steps and secure all information."
09:19:34 a.m. - MCC-FLIGHT: "And folks, listen up again on the flight loop. No phone calls off site outside of this room, our discussions are on these loops, the recorded DVIS (digital voice integrated system) loops only, no data, no phone calls, no transmissions anywhere, into or out."
MCC-GC: "FLIGHT, GC."
MCC-FLIGHT: "GC."
MCC-GC: "We have no way of disabling the black phones."
MCC-FLIGHT: "I understand."
09:20:10 a.m. - MCC-Commentator: "Again, flight director Leroy Cain has declared a contingency. Flight controllers here in mission control are securing all their information, notes and data gathered from the spacecraft. The last communications with Columbia at 8 a.m. Central time as it was descending toward Florida for its landing. At that time, about 207,000 feet above central Texas traveling approximately 12,500 miles per hour, 1,192 miles from its touchdown at Kennedy Space Center. Since 8 a.m., no communications were received with Columbia and no tracking data received through the Merritt Island tracking station, those efforts made. The flight dynamics officer reports no objects tracked through that tracking data."
Thanks for the up-to-date timeline