Integ Time Line Team - REV 15 

BASELINE

3/10/2003 8 

PM Integ Time Line Team - REV 15 BASELINE 3/10/2003 8 PM

Note: Rev 15 BASELINE corrects typo's, adds S-Band comm drop out data, & adds new debris 

observations & jet firings nearest the debris observations.

Note: Rev 15 BASELINE corrects typo's, adds S-Band comm drop out data, & adds new debris observations & jet firings nearest the debris 

observations.

Rev 15 was been baselined by the OVE Working Group Team as of 3/10/03.

Rev 15 was been baselined by the OVE Working Group Team as of 

3/10/03.

Measurement

Seq Sum GMT Milestone Entry Event Remarks MSID / ID Seq GMT MSID Heater Bk Location ID Sample Rate Bit Value Range

Temp Rise Rates / Additional 

Comments

No. No. GMT Day 32 No. GMT Day 32 ID X Y Z Hz (R/256)

1 1 13:10:39 TIG-5 APU 2 Start - Low Press 1 13:10:39

2 2 13:15:30 TIG OMS TIG 2 13:15:30

3 3 13:18:08 OMS End of Burn 3 13:18:08

4 13:26:09 FRCS Dump Start 4 13:26:09

5 13:27:12 FRCS Dump Complete 5 13:27:12

6 4 13:31:25 EI-13 APU 1 Start - Low Press 6 13:31:25

7 5 13:31:29 APU 3 Start - Low Press 7 13:31:29

8 13:31:57 APU 1 Norm Press 8 13:31:57

9 13:31:59 APU 2 Norm Press 9 13:31:59

10 13:32:01 APU 3 Norm Press 10 13:32:01

11 13:32:29 SSME Engine Stow sequence start Sequence was completed with closure of 

TVC Iso Vlv 1 at 13:33:30 GMT.

11 13:32:29

12 13:39:09 EI-5 (304 PRO) Mach 24.40 V90Q8001C 12 13:39:09 V90Q8001C nn nn nn nn nn nn

13 13:39:11 Speedbrake close & Rudder cmded to zero 13 13:39:11

14 6 13:44:09 EI Entry Interface (400,000 Ft) Mach 24.57 14 13:44:09

15 13:46:48 Qbar 0.5 psf Mach 24.66 15 13:46:48

16 13:47:52 Qbar 2.0 psf Elevon, BF active Mach 24.66 16 13:47:52

17 deleted 17 deleted

17.5 13:49:07 ISELECT = 2 Closed-Loop Guidance 17.5 13:49:07

18 13:49:16 Qbar 10 psf Roll Jets Deactivated Mach 24.57 18 13:49:16

19 deleted 19 deleted

20 6.3 13:49:32 Initial Roll Mach 24.51 V90H1044C 20 13:49:32 V90H1044C nn nn nn nn nn nn

20.3 6.5 13:50:00 / 43 Five events of unexpected Return link comm 

drop-out.

Event 1 - 13:50:00 (1 sec); Event 2 - 13:50:04 

/ 06; Event 3 - 13:50:16/22: Event 4 -

13:50:25/28; Event 5 - 13:50:42 (1 sec)

On upper left aft antenna (TDRS 171/W). 

S-Band comm drop-outs considered out-offamily based on comparison with previous 

102 flight data at 39 degrees, into KSC, 

descending node and similar look angles to 

TDRS.

20.3 13:50:00 / 43

20.5 13:50:30 1st Entry 

Heating 

Indication

Nominal Rise in Center Line Bond Temp (1) 

due to Entry Heating

Aft fuselage center bottom bond line V09T1702A 20.5 13:50:30 V09T1702A 1140 -108 309 1 1.46 -75 / 

+300

21 7 13:50:53 Start of Peak 

Heating

Determined by analysis 21 13:50:53

21.5 7.3 13:51:19 / 

13:52:49

Remote sensors indicate off-nominal external 

event - earliest known event

Note: L2L jet firing at 13:51:45.38 / 

51.45.62. L3L jet firing at 13:51:45.36 / 

41.45.60. R2R/R3R jet firings between 

13:52:08 / 52:15 during data loss (firings 

determined by inj temp). R2R/R3R jet 

firings between 13:52:24 / 52:32 during 

data loss (firing determined by inj temps). 

(RCS data taken from Atlas analysis and 

plotted data).

21.5 13:51:19 / 13:52:49

22 7.35 13:51:46 Inertial sideslip angle (Beta) goes and stays 

Negative until LOS

While the magnitude of the observed Beta 

is not outside the flight history (41G & 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.

V90H2249C 22 13:51:46 V90H2249C nn nn nn nn nn nn

22.5 7.4 13:52:05 First clear indication of off-nominal aero 

increments

Delta yawing moment coefficient only (as 

compared to nominal aero). Derived by 

analysis.

22.5 13:52:05

22.6 7.45 13:52:09 / 15 Unexpected Return link comm drop-out 

(Event 6)

On upper left aft antenna (TDRS 171/W). 

S-Band comm drop-out considered out-offamily based on previous flt data (same 

remarks as seq # 20.3 above).

22.6 13:52:09 / 15

23 deleted 23 deleted

23.3 13:52:15 2nd Entry 

Heating 

Indication

Nominal Rise in Center Line Bond Temps (2) 

due to Entry Heating

Mid Fus Lower "Mid" Skin Temp

Mid Fus Bottom Center Bond Line Temp 

X1214

V34T1110A

V34T1112A

23.3 13:52:15 V34T1110A

V34T1112A

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

23.5 7.5 13:52:17 Approx Vehicle 

Ground 

Location:

39.0 N / -129.2 

W

Altitude 236,800 ft / Mach 23.6 - Over the 

Pacific Ocean, approx 300 miles West of 

California Coastline

Approx vehicle position when first offnominal data was seen; Data source: STS107 GPS Trajectory Data23.5 13:52:17
24 8 13:52:17 LMG Brake Line Temp D - On wheel well inbd 

sidewall (aft of sw vlvs) - Start of off nominal 

trend

Initiation of temp rise - off nominal based 

on rise rate comparison with flight 

experience.

V58T1703A 24 13:52:17 V58T1703A 1183 -108 312 1 1.46 -75/+300

24.3 7.45 13:52:25 / 31 Two events of unexpected Return link comm 

drop-out

Event 7 - 13:52:25/26; Event 8 - 13:52:29/31

On upper left aft antenna (TDRS 171/W). 

S-Band comm drop-out considered out-offamily based on previous flt data (same 

remarks as seq # 20.3 above).

24.3 13:52:25 / 31

24.5 deleted 24.5 deleted

24.7 deleted 24.7 deleted

24.8 8.5 13:52:32 Supply H2O dump Nozzle temps A/B show 

temporary increase in temp rise rate (15 

second duration of high rise rate).

High rise rate is bounded by data loss. 

Increase in rise rate not observed on 

previous flights. GMT shown indicates start 

of initial rise duration. Reference event seq 

no. 26.6 for termination of event.

V62T0440A

V62T0439A

24.8 13:52:32 V62T0440A

V62T0439A

24.9 8.5 13:52:32 Vacuum vent temp shows temporary increase 

in temp rise rate (23 second duration of high 

rise rate).

High rise rate is bounded by data loss. 

Increase in rise rate not observed on 

previous flights. GMT shown indicates start 

of initial rise duration. Reference event seq 

no. 26.65 for termination of event.

V62T0551A 24.9 13:52:32 V62T0551A

25 8 13:52:41 LMG Brake Line Temp A - On strut facing 

MLG door - start of off nominal trend

Initiation of temp rise - off nominal based 

on rise rate comparison with flight 

experience.

V58T1700A 25 13:52:41 V58T1700A 1116 -140.4 282.8 1 1.46 -75/+300

25.5 deleted 25.5 deleted

26 8 13:52:41 Left Main Gear Brake Line Temp C - Start of 

off nominal trend

Unusual Temp Rise V58T1702A 26 13:52:41 V58T1702A 1140 -108 309 1 1.46 -75/+300

26.5 deleted 26.5 deleted

26.6 8.5 13:52:47 Supply H2O dump Nozzle temps A/B return to 

typical rise rates.

High rise rate is bounded by data loss. 

GMT shown indicates end of initial rise 

duration. Temp took additional 48 seconds 

to return to nominal temp rise (53:35 

GMT).

V62T0440A

V62T0439A

26.6 13:52:47 V62T0440A

V62T0439A

26.63 7.45 13:52:49 / 55 Unexpected Return link comm drop-out 

(Comm event 9)

On upper left aft antenna (TDRS 171/W). 

S-Band comm drop-out considered out-offamily based on previous flt data (same 

remarks as seq # 20.3 above).

26.63 13:52:49 / 55

26.65 8.5 13:52:55 Vacuum vent temp returns to typical rise rate. High rise rate is bounded by data loss. 

GMT shown indicates end of initial rise 

duration. Temp took additional 40 seconds 

to returns to nominal temp rise (53:35 

GMT).

V62T0551A 26.65 13:52:55 V62T0551A

26.7 13:52:56 Left INBD Elevon Lower Skin Temp - Start of 

off nominal trend

Temp trending down V09T1006A 26.7 13:52:56

27 10 13:52:59 Left INBD Elevon Lower Skin Temp - OSL V09T1006A 27 13:52:59 V09T1006A nn nn nn 1 2.54 -

200/+450

27.2 10.5 13:53:01 First clear indication of off-nominal rolling 

moment increment

Start of steady (-) growth in roll moment, 

derived by analysis

n/a 27.2 13:53:01

27.5 13:53:02 Hyd Syst 1LH INBD Elevon Actr Ret Ln Temp 

- start of off nominal trend

Hyd Syst 3 LOE Ret LN Temp - start of off 

nominal trend

Temp trending down

Temp trending down

V58T0157A

V58T0394A

27.5 13:53:02 V58T0157A

V58T0394A

1350

nn

-219

nn

118

nn

1

1

1.46

nn

-75/+300

nn

28 11 13:53:10 Hyd Syst 3 LOE Ret LN Temp - OSL OSL was preceded by Nominal Temp rise V58T0394A 28 13:53:10 V58T0394A 1368 -368 nn 1 1.46 -75/+300

29 11 13:53:11 Hyd Syst 1LH INBD Elevon Actr Ret Ln Temp 

- OSL

OSL was preceded by Nominal Temp rise V58T0157A 29 13:53:11 V58T0157A 1350 -219 118 1 1.46 -75/+300

29.3 11.1 13:53:24 Alpha 

Modulation

Angle of attack modulation active V90H0803C 29.3 13:53:24 V90H0803C nn nn nn nn nn nn

29.5 11.2 13:53:26 Approx Veh Grd 

Location:

38.7 N / -123.5 

W

Altitude 231600 ft / Mach 23.0 - Crossing the 

California Coastline

Data source: STS-107 GPS Trajectory 

Data

29.5 13:53:26

30 11 13:53:31 / 

53:34

Hyd Syst 1 LOE Return Line Temp - OSL OSL was preceded by Nom Temp rise plus 

data loss 3 sec's prior to event

V58T0193A 30 13:53:31 / 53:34 V58T0193A 1377 -367 436 1 1.46 -75/+300

30.2 11.3 13:53:32 / 34 Unexpected Return link comm drop-out 

(Comm event 10)

On upper left aft antenna (TDRS 171/W). 

S-Band comm drop-out considered out-offamily based on previous flt data (same 

remarks as seq # 20.3 above).

30.2 13:53:32 / 34

30.3 13:53:34 / 

55:57

3rd Entry 

Heating 

Indication

Nominal Rise in Center Line Bond Temps (3) 

due to Entry Heating

13:53:34 - V09T1016A (Mid Fus Bot Port 

BL T X 620);

13:54:00 - V09T1022A (Mid Fus Bot Port 

BL T X 777);

13:55:57 - V09T1624A (Fwd Fus Lwr Skin 

Bot CL T)

V09T1016A

V09T1022A

V09T1624A

30.3 13:53:34 / 55:57 V09T1016A

V09T1022A

V09T1624A

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

nn

30.5 13:53:34 Hyd Sys 2 LIE Return Ln Temp - Start of Off 

Nominal Trend

Temp trending down V58T0257A 30.5 13:53:34 V58T0257A nn nn nn nn nn nn

31 11 13:53:36 Hyd Sys 2 LIE Return Ln Temp - OSL V58T0257A 31 13:53:36 V58T0257A 1348 -219 116 1 1.46 -75/+300

31.5 deleted 31.5 deleted

31.7 deleted 31.7 deleted

32 deleted 32 deleted
32.1 11.5 13:53:44 / 48 Debris #1 

- First report of debris observed 

leaving the Orbiter

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0064

EOC2-4-

0056

32.1 13:53:44 / 48

32.3 11.5 13:53:46 / 50 Debris #2 - Second report of debris observed 

leaving the Orbiter

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0064

EOC2-4-

0056

32.3 13:53:46 / 50

32.5 13:53:46 LMG Brake Line Temp A - On strut facing 

MLG door - Start of off nominal trend (temp 

rise rate change)

Temp rise rate change from 1.4 F/min to 

5.5 F/min and increasing to LOS

V58T1700A 32.5 13:53:46 V58T1700A 1116-140.4 282.81 1.46-75/+300

32.7 11.5 13:53:54 / 58 Debris #3 - Third report of debris observed 

leaving the Orbiter. Event followed by 

momentary brightening of plasma trail.

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

Debris:

EOC2-4-

0056, 0026

Trail:

EOC2-4-

0064, 0056

32.7 13:53:54 / 58

32.8 11.5 13:54:00 / 04 Debris #4 - Fourth report of debris observed 

leaving the Orbiter

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0056

EOC2-4-

0026

32.8 13:54:00 / 04

32.9 11.5 13:54:07 / 11 Debris #5 - Fifth report of debris observed 

leaving the Orbiter

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0056

EOC2-4-

0026

32.9 13:54:07 / 11

33 13 13:54:10 LMG Brake Line Temp B - Start of off nominal 

trend

Temp Increase V58T1701A 33 13:54:10 V58T1701A 1116-139.6 282.81 1.46-75/+300

33.5 11.3 13:54:14 / 22 Unexpected Return link comm drop-out 

(Comm event 11)

On upper left aft antenna (TDRS 171/W). S-Band comm drop-out considered out-of

-

family based on previous flt data (same 

remarks as seq # 20.3 above).

33.5 13:54:14 / 22

34 14 13:54:20 Start of slow aileron trim change GMT is approximate (13:54:20 +/- 10 

seconds)

V90H1500C 34 13:54:20 V90H1500C nn nn nn nn nn nn

34.5 14 13:54:20 Reversal in growth trend of derived roll 

moment coefficient

Observed moment changed from a 

negative slope to positive slope. Derived 

by analysis.

n/a 34.5 13:54:20

35 15 13:54:22M-FUS LT BL Temp at x1215 - start of off 

nominal trend (increased rise rate)

Unusual Temp Rise (Rise rate higher than 

STS-109 & 87). Rise rate increased from 1 

F/min (typical) to 7.6 F/min.

V34T1106A 35 13:54:22 V34T1106A 1215 nn nn1 nn nn

35.2 15 13:54:22 LH Aft Fus Sidewall Temp at x1410 - start of 

off nominal trend (increased rise rate)

Unusual Temp Rise (Rise rate higher than 

STS-109 & 87). Rise rate increased from 

2.7 F/min (typical) to 5.5 F/min.

V09T1724A 35.2 13:54:22 V09T1724A 1410 nn nn nn nn nn

35.5 13 13:54:24 Sys 3 Left Main Gear Strut Actuator Temp -

start of off nominal trend

Unusual Temp Rise V58T0405A 35.5 13:54:24 V58T0405A 1183-115 3151 1.46-75/+300

35.7 13:54:25 Approx Veh Grd 

Location:

38.3 N / -119.0 

W

Altitude 227400 ft / Mach 22.5 - Crossing the 

California / Nevada State Line

Data source: STS-107 GPS Trajectory 

Data

35.7 13:54:25

35.8 13:54:26S-Band switched from upper left aft antenna 

to upper right aft antenna

TDRS 171/W 35.8 13:54:26

36 deleted 36 deleted

36.5 15.3 13:54:33.3 / 

33.9

Flash #1 - Orbiter envelope suddenly 

brightened (duration 0.3 sec), leaving 

noticeably luminescent signature in plasma 

trail

Note: R3R and R2R 0.24 sec jet firings 

occurred at 13:54:33.52 / 33.76 and 

13:54:33.54 / 33.78 respectively (ref: RCS 

Atlas analysis and plots).

EOC2-4-

0026

EOC2-4-

0034

EOC2-4-

0009B

36.5 13:54:33.3 / 33.9

36.6 15.3 13:54:35 / 37 Debris #6 - Very bright debris seen leaving 

the Orbiter

Seen just aft of Orbiter envelope. Also, 

reference RCS jet firing note in item # 36.5 

above. Debris events 6 and 14 are visually 

the biggest, brightest events and therefore 

may indicate the most significant changes 

to the Orbiter of the western debris events.

EOC2-4-

0026

EOC2-4-

0009B

EOC2-4-

0030

36.6 13:54:35 / 37

37 deleted 37 deleted

37.5 deleted 37.5 deleted

37.7 13:54:53 MLG LH Outbd Wheel Temp - start of off 

nominal trend

2 bit flips up (ref #56.5 when temp starts to 

trend down)

V51T0574A 37.7 13:54:53 V51T0574A 1074-115 nn1 0.98-75/+300

37.75 15.35 13:55:04 / 10 Debris #7 - Seventh report of debris observed 

leaving the Orbiter

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0030

37.75 13:55:04 / 10

37.8 13 13:55:12 Sys 3 LMG Brake Sw Vlv Ret Line Temp 

(FWD) - start of off nominal trend

Temp Increase V58T0842A 37.8 13:55:12 V58T0842A 1156-110 3141 1.46-75/+300

38 deleted 38 deleted

39 deleted 39 deleted

40 13:55:21 Drag 11 fps2 Drag Measurement Incorporation Mach 21.nn 40 13:55:21
40.1 15.35 13:55:21 / 27 Debris #8 - Eighth report of debris observed 

leaving the Orbiter. Event was followed by 

momentary brightening of plasma trail.

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

Debris: 

EOC2-4-

0030; trail: 

EOC2-4-

0005, 0017, 

0021, 0028, 

and 0030

40.1 13:55:21 / 27

40.2 15.35 13:55:25 / 29 Debris #9 - Ninth report of debris observed 

leaving the Orbiter. Event was followed by 

multiple secondary plasma trails.

Seen just aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0030, 0050

40.2 13:55:25 / 29

40.3 15.35 13:55:26 / 30 Debris #10 - Tenth report of debris observed 

leaving the Orbiter

Seen well aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0005

40.3 13:55:26 / 30

40.4 15.4 13:55:30 Remote sensors indicate off-nominal external 

event

GMT is approximate. 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 (ref Atlas data and plots).

40.4 13:55:30

40.5 13:55:32 Approx Veh Grd 

Location:

37.4 N / -114.1 

W

Altitude 223400 ft / Mach 21.8 - Crossing the 

Nevada / Utah State Line

Data source: STS-107 GPS Trajectory 

Data

40.5 13:55:32

40.6 13:55:33 / 35 Return link comm drop-out (Comm event 12) First comm drop out after switched to 

upper right aft antenna (TDRS 171/W). 

While uncommon to have a drop out at this 

point, inconclusive if drop-out is off-nominal 

based on previous flt data.

40.6 13:55:33 / 35

41 deleted 41 deleted

41.5 15.45 13:55:36 / 42 Debris #11 - Eleventh report of debris 

observed leaving the Orbiter

Seen well aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0050

41.5 13:55:36 / 42

42 15.5 13:55:41 Mid Fus Port (Left) Sill Longn Temp at x1215 -

start of off nominal trend

Unusually high temp rise with respect to 

STS-87 & 109. Went to 2.6 F/min from 0 

F/min.

V34T1118A 42 13:55:41 V34T1118A nn nn nn nn nn nn

42.3 15.45 13:55:45 / 49 Debris #12 - Twelfth report of debris observed 

leaving the Orbiter. Event was preceded and 

followed by secondary plasma trails.

Seen aft of Orbiter envelope. No evidence 

of RCS jet firings (ref Atlas data and plots).

EOC2-4-

0028, 0050

42.3 13:55:45 / 49

42.5 13:55:55 Approx Veh Grd 

Location:

37.0 N / -112.4 

W

Altitude 222100 ft / Mach 21.5 - Crossing the 

Utah / Arizona State Line

Data source: STS-107 GPS Trajectory 

Data

42.5 13:55:55

42.7 15.45 13:55:55 / 59 Debris #13 - Thirteenth report of debris 

observed leaving the Orbiter. Event was 

followed by momentary brightening of plasma 

trail adjacent to debris.

Seen well aft of Orbiter envelope. No 

evidence of RCS jet firings (ref Atlas data 

and plots).

EOC2-4-

0005, 0017, 

0021

42.7 13:55:55 / 59

42.8 15.45 13:55:58 / 

56:00

Debris #14 - Very bright debris observed 

leaving the Orbiter.

Seen just aft of Orbiter envelope. Debris 

events 6 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 (ref Atlas data and plots).

EOC2-4-

0005, 0017, 

0021, 0028, 

0030

42.8 13:55:58 / 56:00

42.9 13:56:00 / 03 Return link comm drop-out (Comm event 13) On upper right aft antenna (TDRS 171/W). 

While uncommon to have a drop out at this 

point, inconclusive if drop-out is off-nominal 

based on previous flt data.

42.9 13:56:00 / 03

43 13:56:02 Qbar 40 psf Aft RCS Pitch Jets Deactivated 43 13:56:02

44 16 13:56:03 Left Lower Wing Skin Temp - start of off 

nominal trend

Temp reading trending down (potential 

sensor/wire damage)

V09T1002A 44 13:56:03 V09T1002A 1280.1 240 LWR 1 2.54 -

200/+450

44.2 15.45 13:56:09 / 13 Debris #15 - Fifteenth report of debris 

observed leaving the Orbiter.

Seen just aft of Orbiter envelope. Nearest 

jet firings: R2R jet firing at 032:13:56:17.30 

/ 56:17.54 for 0.24 seconds, & R3R jet 

firing at 032:13:56:17.28 / 56:17.52 for 0.24 

seconds. (Ref: RCS Atlas data analysis 

and plots).

EOC2-4-

0017

44.2 13:56:09 / 13

44.5 16.5 13:56:16 Hyd Sys 1 LMG UpLK Actr Unlk Ln Temp -

Temp rise rate change

Temp rise rate change from 0.7 F/min 

(nominal) to 3.9F/min and increasing to 

LOS

V58T0125A 44.5 13:56:16 V58T0125A 1159 -124 315 1 1.46 -75/+300

44.6 16.5 13:56:17 Sys 3 LMG Brake Sw Vlv Ret Line Temp 

(FWD) - Temp rise rate change

Temp rise rate change from 1.5 F/min to 

8.8 F/min (stayed at this rate to LOS)

V58T0842A 44.6 13:56:17 V58T0842A 1156 -110 314 1 1.46 -75/+300

44.7 16.5 13:56:20 LMG Brake Line Temp C - Temp rise rate 

change

Temp rise rate change from 1.3 F/min to 

9.9 F/min (stayed at this rate to LOS)

V58T1702A 44.7 13:56:20 V58T1702A 1140 -108 309 1 1.46 -75/+300
44.8 16.5 13:56:22 LMG Brake Line Temp B 

- Temp rise rate 

change

Temp rise rate change from 2.1 F/min to 

9.1 F/min increasing to LOS

V58T1701A 44.8 13:56:22 V58T1701A 1116-139.6 282.81 1.46-75/+300

45 16 13:56:24 Left Upper Wing Skin Temp - start of off 

nominal trend

Temp reading trending down (potential 

sensor/wire damage)

V09T1024A 45 13:56:24 V09T1024A 1280.1 240 UPR1 2.54-

200/+450

46 16.55 13:56:30 1st Roll Reversal Initiation Mach 21.13 V90H1044C 46 13:56:30 V90H1044C nn nn nn nn nn nn

46.5 13:56:45 Approx Veh Grd 

Location:

36.1 N / -109.0 

W

Altitude 219000 ft / Mach 20.9 - Crossing the 

Arizona / New Mexico State Line

Data source: STS-107 GPS Trajectory 

Data

46.5 13:56:45

46.7 16.5 13:56:53 Sys 3 Left Main Gear Strut Actuator Temp -

Temp rise rate change

Temp rise rate change from 1.7 F/min to 

12.9 F/min (stayed at this rate to LOS)

V58T0405A 46.7 13:56:53 V58T0405A 1183-115 3151 1.46-75/+300

47 16.55 13:56:55 Roll Reversal #1 1st Roll Reversal Complete Mach 20.76 V90H1044C 47 13:56:55 V90H1044C nn nn nn nn nn nn

47.5 13:56:55 / 57 Return link comm drop-out (Comm event 14) On upper right aft antenna (TDRS 171/W). 

While uncommon to have a drop out at this 

point, inconclusive if drop-out is off-nominal 

based on previous flt data.

47.5 13:56:55 / 57

Note: No further comm drop-out events are 

listed in the timeline thru LOS, since they 

are not considered out-of-family at this 

time.

48 13:56:58 IMU Velocity Increase Reflects accelerations imparted during roll 

reversal. Same signature observed on 

STS-109. Nominal event.

48 13:56:58

49 13:57:nn Bodyflap deflection up 3 degrees Matches nominal aero simulation V90H6410C 49 13:57:nn V57HxxxxC nn nn nn nn nn nn

49.5 deleted 49.5 deleted

49.55 16.8 13:57:19 / 29 Debris # 16 - Very faint debris observed 

leaving just aft of Orbiter (occurred over NM)

Observations by personnel from the 

Starfire Optical Range (Kirtland Air Force 

Base, NM).

Note: nearest jet firings: L2L jet firing at 

032:13:56:54.71 / 57:01.12 & 

032:13:57:46.35 / 57:53.12 & L3L jet firing 

at 032:13:56:54.66 / 57:01.07 & 

032:13:57:46.33 / 57:53.10 (all 4 occurred 

during data dropouts & were determined 

based on injector temps alone). Also, R2R 

at 032:13:57:43.94 / 57:44.42 & R3R at 

032:13:57:43.92 / 57:44.40 for 0.48 secs 

ea. (Ref Atlas data analysis and plots.)

EOC2-4-

0148-2

49.55 13:57:19 / 29

49.6 16.9 13:57:19 MLG LH Outbd Tire Pressure 1 - start of off 

nominal trend

Bit flip up - off nominal thru comparison 

with previous flights

V51P0570A 49.6 13:57:19 V51P0570A 1074-160 nn1 0.67 230 / 401

49.7 16.9 13:57:24 MLG LH Outbd Tire Pressure 2 - start of off 

nominal trend

Bit flip up - off nominal thru comparison 

with previous flights

V51P0572A 49.7 13:57:24 V51P0572A 1074-160 nn1 0.67 230 / 401

50 17 13:57:28 Left Lower Wing Skin Temp - OSL V09T1002A 50 13:57:28 V09T1002A 1280.1 240 LWR1 2.54-

200/+450

51 deleted Rationale for deletion: Originally indicated as "Start of 

Roll trim in elevons". Inserted independently early in 

the investigation, but is better defined by sequence 

no. 54. "Roll trim" is better indicated with aileron trim.

51 deleted

52 17 13:57:43 Left Upper Wing Skin Temp - OSL V09T1024A 52 13:57:43 V09T1024A 1280.1 240 UPR1 2.54-

200/+450

53 19 13:57:54 Sys 2 LH Brake Switching Vlv Return Temp 

(AFT) - start of off nominal trend

Temp increase V58T0841A 53 13:57:54 V58T0841A 1173-107 3131 1.46-75/+300

53.5 16.8 13:57:53.7 / 

55.7

Flare 1: Asymmetrical brightening of Orbiter 

shape observed (occurred over NM)

Observations by personnel from the 

Starfire Optical Range (Kirtland Air Force 

Base, NM).

Note: nearest jet firings: Same as seq no. 

49.55 plus L2L at 032:13:58:00.50 / 01.46 

& L3L at 032:13:58:00.48 / 01.44 (in both 

cases there was no start up data, but good 

tail off/shutdown) - 0.96 sec pulse each. 

Also, R2R at 032:13:58:03.18 / 09.16 & 

R3R at 032:13:58:03.18 / 09.16 - (in both 

cases firings occurred during data dropouts 

and were determined by injector temps). 

(Ref Atlas analysis and plots.)

EOC2-4-

0148-4

53.5 13:57:53.7 / 55.7

53.7 16.8 13:57:59.5 / 

58:01.5

Flare 2: Asymmetrical brightening of Orbiter 

shape observed (occurred over NM)

Observations by personnel from the 

Starfire Optical Range (Kirtland Air Force 

Base, NM).

Note: same jet firing information as for 

event seq no.s 49.55 & 53.5. (Ref Atlas 

analysis and plots.)

EOC2-4-

0148-4

53.7 13:57:59.5 / 58:01.5

54 20 13:58:03 Start of "sharp" aileron trim increase Mach 19.79; GMT is approximate 

(13:58:03+/-10 seconds)

V90H1500C 54 13:58:03 V90H1500C nn nn nn nn nn nn

54.3 20.5 13:58:09 Increase in derived rolling and yawing 

moment increments

Sustantial increase in observed growth rate 

of both roll and yaw moment increments. 

Derived by analysis.

n/a 54.3 13:58:09

54.5 22.5 13:58:16 LMG Brake Line Temp D - Temp rise rate 

change

Temp rise rate change from 0.9 F/min to 

11.7 F/min (stayed at this rate to LOS)

V58T1703A 54.5 13:58:16 V58T1703A 1183-108 3121 1.46-75/+300

55 deleted 55 deleted

55.5 13:58:20 Approx Veh Grd 

Location:

34.2 N / -103.1 

W

Altitude 209800 ft / Mach 19.5 - Crossing the 

New Mexico / Texas State Line

Data source: STS-107 GPS Trajectory 

Data

55.5 13:58:20
56 deleted 56 deleted

57 23 13:58:32 MLG LH Outbd Tire Pressure 1 - pressure 

trending down (to OSL)

Trending to OSL following 7 sec LOS 

(initiation time not exact) - ref #60

V51P0570A 57 13:58:32 V51P0570A 1074-160 nn1 0.67 230 / 401

58 23 13:58:32 MLG LH Inbd Tire Pressure 1 - pressure 

trending down (to OSL)

Trending to OSL following 7 sec LOS 

(initiation time not exact) - ref #64

V51P0571A 58 13:58:32 V51P0571A 1074-115 nn1 0.67 230 / 401

58.5 13:58:32 MLG LH Outbd Wheel Temp - temperature 

trending down (to OSL)

Trending to OSL following 7 sec LOS 

(initiation time not exact) - ref #62

V51T0574A 58.5 13:58:32 V51T0574A 1074-160 nn1 0.67 230 / 401

58.7 13:58:32 / 

59:22

Sys 2 LH Brake Switching Vlv Return Temp 

(AFT) - temp rise rate change

Temp rise rate change from 2.5 F/min to 

40.0 F/min until 13:59:22 (temp peak) - ref 

#70.5

V58T0841A 58.7 13:58:32 / 59:22 V58T0841A

59 13:58:36 MLG LH Inbd Wheel Temp - start of 

temperature trending down (to OSL)

Start of trend to OSL - ref #66 V51T0575A 59 13:58:36 V51T0575A 1074-115 nn1 0.98-75 / 

+175

60 23 13:58:38 MLG LH Outbd Tire Pressure 1 - OSL V51P0570A 60 13:58:38 V51P0570A 1074-160 nn1 0.67 230 / 401

61 deleted Rationale for deletion: Moved to seq no. 63.5 after 

further data review.

61 deleted

62 25 13:58:39 MLG LH Outbd Wheel Temp - OSL V51T0574A 62 13:58:39 V51T0574A 1074-115 nn1 0.98-75 / 

+175

63 23 13:58:39 MLG LH Outbd Tire Pressure 2 - start of 

pressure trending down (to OSL)

Start of trend to OSL - ref #68 V51P0572A 63 13:58:39 V51P0572A 1074-160 nn1 0.67 230 / 401

63.5 25.5 13:58:40 BFS Fault Msg (4) - Tire Pressures - First 

Message

32/13:58:39.94 - SM0 Tire P LOB

32/13:58:41.84 - SM0 Tire P LIB

32/13:58:49.54 - SM0 Tire P LIB

32/13:58:56.26 - SM0 Tire P LOB

63.5 13:58:40

64 23 13:58:40 MLG LH Inbd Tire Pressure 1 - OSL V51P0571A 64 13:58:40 V51P0571A 1074-115 nn1 0.67 230 / 401

65 13:58:41 MLG LH Inbd Tire Pressure 2 - start of off 

nominal trend

Press rose ~3.5 psia in 2 sec's V51P0573A 65 13:58:41 V51P0573A nn nn nn1 0.67 230 / 401

65.5 23 13:58:43 MLG LH Inbd Tire Pressure 2 - start of 

pressure trending down

V51P0573A 65.5 13:58:43 V51P0573A nn nn nn 0.67 230 / 401

66 25 13:58:48 MLG LH Inbd Wheel Temp - OSL V51T0575A 66 13:58:48 V51T0575A nn nn nn1 0.67 230 / 401

67 23 13:58:48 MLG Inbd Tire Pressure 2 - OSL V51P0573A 67 13:58:48 V51P0573A nn nn nn1 0.67 230 / 401

68 23 13:58:54 MLG LH Outbd Tire Pressure 2 - OSL V51P0572A 68 13:58:54 V51P0572A 1074-160 nn1 0.67 230 / 401

69 26 13:58:56 BFS Fault Msg (4) - Tire Pressures - Last 

Message

69 13:58:56

70 27 13:59:06 Left Main Gear Downlocked Indication -

Transferred ON

Uplock indicated no change V51X0125E 70 13:59:06 V51X0125E 1189-135 nn1 n/a 0 / 1

70.3 27.5 13:59:23 Loss of MCC real-time data to the 

workstations in the FCR and MER

70.3 13:59:23

70.5 13:59:22 Sys 2 LH Brake Switching Vlv Return Temp 

(AFT) - start of sharp downward temperature 

trend

Temp trending down until loss of signal -

ref #81

V58T0841A 70.5 13:59:22 V58T0841A 1173-107 3131 1.46-75/+300

71 28 13:59:30.66 Start of R2R yaw firing Last pulse before LOS (stayed on to end of 

first 5-sec period of recon data at 

032/13:59:37.4 GMT)

V79X2634X 71 13:59:30.66 V79X2634X nn nn nn nn n/a 0 / 1

72 28 13:59:30.68 Start of R3R yaw firing Last pulse before LOS (stayed on to end of 

first 5-sec period of recon data at 

032/13:59:37.4 GMT)

V79X2638X 72 13:59:30.68 V79X2638X nn nn nn nn n/a 0 / 1

73 29 13:59:31 Observed elevons deflection at LOS Left: -8.11 deg (up); Right: -1.15 deg (up) V90H7505C

V90H7555C

73 13:59:31

73.1 29.3 13:59:31.400 FCS Channel 4 Aerosurface position 

measurements start trending towards their 

null values

Indicates worsening failure of transducer 

excitation via a wiring short conditions

V57H0253A

(5 Hz)

73.1 13:59:31.400

73.2 29.3 13:59:31.478 All FCS Channel 4 Bypass valves close 

(indicating bypassed)

Leading indicator of ASA fail (high-rate 

data)

V58P0915A 73.2 13:59:31.478

73.3 29.3 13:59:31.7 Speedbrake channel 4 OI position 

measurement indicated successively 19, 20, 

24 degrees over last three samples prior to 

LOS (should be closed / 0o).

Speedbrake was commanded to 

"overclose" (-10 degrees), position 

measurements for Channels 1 thru 3 were 

0 degrees. Secondary delta pressure on 

Ch 4 went to zero, which indicates that the 

channel was bypassed. This is real data 

and the ASAs were responding 

appropriately.

V57H0253A

(5 Hz)

73.3 13:59:31.7 V57H0253A nn nn nn5 nn nn

73.5 29.5 13:59:32 Observed aileron trim at LOS Trim: -2.3 deg (V96H2045C - V90H1500C) 73.5 13:59:32

74 13:59:32M-FUS LT BL Temp at x1215 - LOS LOS V34T1106A 74 13:59:32 V34T1106A 1215 nn nn1 nn nn

74.5 13:59:32 LH Aft Fus Sidewall Temp at x1410 - LOS LOS V09T1724A 74.5 13:59:32 V09T1724A 1410 nn nn nn nn nn

75 13:59:32 LMG Brake Line Temp A - LOS LOS at 172.2 F V58T1700A 75 13:59:32 V58T1700A 1116-140.4 282.81 1.46-75/+300

76 13:59:32 LMG Brake Line Temp B - LOS LOS at 154.2 F V58T1701A 76 13:59:32 V58T1701A 1116-139.6 282.81 1.46-75/+300

77 13:59:32 LMG Brake Line Temp C - LOS LOS at 104.8 F V58T1702A 77 13:59:32 V58T1702A 1140-108 3091 1.46-75/+300

78 13:59:32 LMG Brake Line Temp D - LOS LOS at 88.3 F V58T1703A 78 13:59:32 V58T1703A 1183-108 3121 1.46-75/+300

79 13:59:32 Left Main Gear Strut Actuator Temp - LOS LOS at 76.3 F V58T0405A 79 13:59:32 V58T0405A 1183-115 3151 1.46-75/+300

80 13:59:32 Hyd Sys 1 LMG Uplk Actr Unlk Ln Temp -

LOS

LOS at 52.2 F V58T0125A 80 13:59:32 V58T0125A 1159-124 3151 1.46-75/+300

81 13:59:32 Sys 2 LH Brake Sw Vlv Return Temp (AFT) -

LOS

LOS at 62.8 F V58T0841A 81 13:59:32 V58T0841A 1173-107 3131 1.46-75/+300

82 13:59:32 Sys 3 LMG Brake Sw Vlv Return Line Temp 

(FWD) - LOS

LOS at 67.3 F V58T0842A 82 13:59:32 V58T0842A 1156-110 3141 1.46-75/+300
82.7 32.5 31:59:32 Approx Veh Grd 

Location:

32.9 N / -99.0 W

Altitude ~200700 ft / Mach ~18.1 - Near 

Dallas TX

Approximate Vehicle Ground Location at 

Loss of Signal based on GMT; Data 

source: STS-107 GPS Trajectory Data

82.7 31:59:32

82.8 29.3 13:59:32.130 FCS Channel 4 fail flags raised (1 Hz) on all 

aerosurface actuators

Lagging indicator of ASA position 

measurement discrepancy

V79X3263X

V79X3268X

V79X3273X

V79X3278X

V79X3334X

V79X3339X

82.8 13:59:32.130

83 33 13:59:32.136 LOS

(Loss of Signal)

Last valid downlink frame accepted by ODRC 

- OI / BFS / PASS

(This time has been referred to as "LOS" 

thoughout the investigation.)

Start of reconstructed data

Upper Right Aft (URA) Quad Antenna was 

selected by BFS antenna management 

S/W to communicate with TDRS-W. The 

pointing angle to TDRS-W was off the Orb 

tail at -65 degs and trending further into 

blockage. Prev experience / eng calcs 

predict probable loss of comm at elevation 

angles greater than -60 degrees. Loss of 

comm at this GMT is therefore considered 

nominal.

83 13:59:32.136

84 29.3 13:59:32.195 ASA 4 RPC A&C Trip Indication Lagging indicator of ASA transducer 

excitation short condition

V79X4210E

V76X4211E

84 13:59:32.195

85 deleted Rationale for deletion: moved to 85.6 after further 

data review.

85 deleted

85.5 29.3 13:59:32.598 Left Outboard bypass valve reopens. A force 

fight between channels 1/2/3 and channel 4 

begins, resulting in a difference of up to 0.5 

degrees observed between the left outboard 

and inboard elevons

Indicates a short in bypass valve has 

grown sufficient to drop below voltage 

threshold of valve; RPC B is current 

limiting.

V58P0865A 85.5 13:59:32.598

85.6 29.3 13:59:33.680 BFS Fault Message annunciation (1) - FCS 

CH 4

TDRS-E Data. Error is detected by 

ATVC/ASA hardware when sensed delta 

pressure across actuator exceeds a limit 

indicating the FCS channel is no longer 

driving the actuator. FCS CH 4 failure will 

annunicate for any of the following: LIB / 

LOB / RIB / ROB elevon actutor 4, rudder 

actuator 4, speedbrake actuator 4, SSME 

1/2/3 P/Y Actuator D, & L/R SRB R/T 

actuator D.

85.6 13:59:33.680

86 29.3 13:59:33.863 PASS Fault Message annunciation (1) - FCS 

CH 4

TDRS-E Data 86 13:59:33.863

87 13:59:33.976 Master Alarm noted. D&C analysis is continuing to determine 

cause of alarm.

87 13:59:33.976

88 29.3 13:59:34.518 Left Outboard force fight ends, driver currents 

go to zero.

(RPC B trip indication).

Leading indicator of RPC B trip / ASA 

power down. I.e., indicates opening of all 

bypass valves (due to RPC B trip removing 

power) on ASA 4. Force fight goes away 

since actuators are already at the last 

commanded position (so channel 4 has no 

hyd load on the servo asking for position 

change).

V58P0865A 88 13:59:34.518

89 29.3 13:59:34.561 Speedbrake force fight begins (continues to 

LOS)

Indicates opening of all bypass valves (due 

to RPC B trip removing power) on ASA 4. 

Since the speedbrake is at zero but is 

being commanded to "over-close" position 

(-10) this results in a force fight between 

channels 1,2,3 and channel 4.

V57P0260A

V57P0261A

V57P0262A

89 13:59:34.561
90 35 13:59:35/36 Sideslip on vehicle changes sign. The event occurred between the two times 

listed. Just prior to initial LOS the 

magnitude of the negative Sideslip started 

to decrease and between 59:34 and 59:37 

sideslip grew from -.6 to +.8 deg. With this 

change, the normal roll and yaw moments 

on the vehicle would change sign. 

Aerodynamic forces due to sideslip are 

now reinforcing aerodynamic asymmetry.

90 13:59:35/36

91 36 13:59:36 Growth in Bank attitude error Up until this time the flight control had been 

able to maintain the Bank error around 5 

deg. Aerojet DAP drops left wing to 

compensate for increasing aerodymanic 

moments, creating a bank attitude error.

91 13:59:36

92 37 13:59:36.8 Aerojet DAP Requests Third Right Yaw RCS 

Jet (R4R)

This additional jet is required to counteract 

the increasing aerodynamic moments on 

the vehicle. The RCS jet fired, as expected 

and stayed on to end of first 5-sec period 

of recon data at 032/13:59:37.4 GMT.

92 13:59:36.8

93 38 13:59:37.3 Aerojet DAP Requests Fourth Right Yaw RCS 

Jet (R1R)

This additional jet is required to counteract 

the increasing aerodynamic moments on 

the vehicle. The RCS jet fired, as expected 

and stayed on to end of first 5-sec period 

of recon data at 032/13:59:37.4 GMT.

93 13:59:37.3

94 39 13:59:37.n Last aileron data The aileron position is now approx -5.2 deg 

with approx -2.5 deg of aileron trim. The 

rate of change of aileron trim had reached 

the maximum allowed by the flight control 

system.

94 13:59:37.n

95 40 13:59:37.396 End of 5 second 

period of 

reconstructed 

data

End of first 5-seconds of the 32-second period 

of post-LOS data. Start of approximately 25 

seconds of no data available

GMT derived by MER data personnel 95 13:59:37.396

96 41 13:59:46.347 PASS Fault Message annunciation - ROLL 

REF

Message retrieved from "fault message 

buffer" received between 14:00:04 and 

14:00:05. The ROLL REF message is 

triggered when Roll command req'd to fly 

reference profiile falls below 37 degs. 

Message generation less than 10 secs (5 

guidance cycles) after start of 4 yaw jets 

firing suggests rapid change in Lift to Drag 

ratio.

96 13:59:46.347

Note: BFS does not have this message in 

the Fault message stack. It is likely that 

BFS annunciated this message during the 

25 second gap of no data, but that if it was 

annunciated it was pushed out of the 

downlist stack by additional fault messages 

(at least 5) annunciated during the gap.

97 41 13:59:52.114 PASS Fault Message annunciation - L RCS 

LEAK

Data located in PASS fault message 

buffer. Data is potentially error prone.

97 13:59:52.114

98 41 14:00:01.540* BFS Fault Message annunciation - L RCS 

LEAK

Data located in BFS fault message buffer. 

Data is potentially error prone.

*Time info corrupted.

98 14:00:01.540*

99 41 14:00:01.900* BFS Fault Message annunciation - L RCS 

LEAK

Data located in BFS fault message buffer. 

Data is potentially error prone.

*Time info corrupted.

99 14:00:01.900*
100 42 14:00:02/06 Debris A observed leaving the Orbiter - Large 

debris seen falling away from the Orbiter 

envelope.

EOC2-4-

0024

EOC2-4-

0018

EOC2-4-

0118

100 14:00:02/06

101 43 14:00:02.654 PASS Fault Message annunciation - L RCS 

LJET

Data is potentially error prone. 101 14:00:02.654

102 44 14:00:02.660 Beginning of 2 

second period of 

reconstructed 

data

Start of last 2-seconds of the 32 second 

period of post-LOS data.

GMT derived by MER data personnel. 102 14:00:02.660

CAUTION: Data from this period is suspect because multiple bit errors were evident in 

this reconstructed data. Many of the parameters were 1 Hz data and therefore only one 

data sample was available. Where possible, high rate data and/or corroborating data were 

used to draw subsystem performance conclusions. However, some of the conclusions 

drawn below may be in error or misinterpreted.

During this final 2 second period of reconstructed data, the data indicates the following 

systems were nominal: APUs were running and WSB cooling was evident (although 

potentially overcooling). MPS integrity was still evident. Fuel cells were generating power 

and the PRSD tanks/lines were intact. Comm and navaids systems in the forward 

fuselage were performing nominally. RSB, Body Flap, main engine, and right wing temps 

appeared active. With the exception of an apparent FES shutdown, ECLSS performance 

was nominal.

During this final 2 second period of reconstructed data, the data indicates the following 

systems were off-nominal: All three Hyd systems were lost (zero pressure/zero rsvr qty's). 

The left inbd/outbd elevon actuator temps were either OSL or no data exists. WSB's 

appeared to be overcooling APU lube oil. The FES appeared to have shutdown. Majority 

of left OMS pod sensors were either OSH or OSL or no data exists. Multiple BFS and 

PASS fault message annunciations for left pod hardware were found in the buffer. 

Elevated temps at bottom bondline centerline skin forward and aft of the wheel wells and 

at the port side structure over left wing were observed. EPDC shows general upward shift 

in Main Bus amps and downward shift in Main Bus volts. AC3 phase A inverter appeared 

disconnected from the AC Buss.

GNC data suggests vehicle was in an uncommanded attitude and was exhibiting 

uncontrolled rates. Yaw rate was at the sensor maximum of 20 deg/sec. The flight control 

mode was in AUTO. (Note that all Nav-derived parameters (e.g., alpha) are suspect due 

to high rates corrupting the IMU state.)

Based on the nominal and off-nominal system performance described above, it appears 

that the fwd/mid/aft fuselage, right wing, and right pod were still intact.

103 45 14:00:03.470* BFS Fault Message annunciation - L OMS TK 

P

Data located in BFS fault message buffer 

after acquisition of data. Data is potentially 

error prone. *Time info corrupted.

Note: Error is annunciated when left OMS 

oxidizer tank ullage pressure (V43P4221C) 

or fuel tank ullage pressure (V43P4321C) 

is out of limits high or low. Oxidizer limits -

High: 288 psi; Low 234 psi; Fuel limits -

High: 288 psi; Low: 234 psi.

103 14:00:03.470*

103.5 45 14:00:0n.nnn BFS Fault Message annunciation - Indeterminant103.5 14:00:0n.nnn

104 45 14:00:0n.nnn* BFS Fault Message annunciation - SM1 AC 

VOLTS

Occurred after L OMS TK P message. 

Data is potentially error prone. *Time info 

corrupted.

Note: Error message indicates that AC Bus 

3 phase A, B, or C voltage (V76V1700A, 

V75V1701A, V76V1702A) is out of limits 

high or low. Low limit for all 3 parameters is 

108VAC; High limit is 123VAC.

104 14:00:0n.nnn*

105 45 14:00:03.637 PASS Fault Message annunciation - L RCS 

PVT

Data is potentially error prone. 105 14:00:03.637
106 46 14:00:03.637 PASS Fault Message annunciation - DAP 

DNMODE RHC

The software process which logs the PASS 

message runs every 1.92 seconds, so 

event could have occurred as early as 

14:00:01.717 GMT. The fault message was 

corroborated by an initialization flag for the 

aerojet DAP roll stick function. However, 

during the 2 sec period, available vehicle 

data indicates RHC was in detent & DAP 

was in AUTO. Data is potentially error 

prone.

106 14:00:03.637

Note: BFS downlist bits indicating CSS 

mode are initialized to "ON" for entry 

because BFS does not have an "Auto" 

mode, is always CSS, and will drive the 

eyebrow panel lights ON if engaged. These 

bits are always on in BFS through all of 

OPS 3 until touchdown.

107 47 14:00:04.826 End of 2 second 

period of 

reconstructed 

data

Last identifiable OI Downlink frame GMT derived by MER data personnel. Last 

recognizable Downlist frame (BFS & 

PASS) was approx 60 ms earlier.

107 14:00:04.826

108 48 14:00:17/21 Debris B observed leaving the Orbiter Time is for debris first seen well aft of 

Orbiter envelope.

EOC2-4-

0024

EOC2-4-

0118

108 14:00:17/21

109 48 14:00:18/22 Debris C observed leaving the Orbiter Time is for debris first seen well aft of 

Orbiter envelope.

EOC2-4-

0024

EOC2-4-

0118

109 14:00:18/22

110 49 14:00:21/25 Vehicle Main Body break-up Onset of vehicle main body break-up EOC2-4-

0024

EOC2-4-

0018

EOC2-4-

0118

110 14:00:21/25

111 50 14:00:53 End of Peak 

Heating

Determined by analysis 111 14:00:53

= Expected/Nominal performance or 

event nn = data still needed = Expected/Nominal performance or event nn = data still needed