- Chronologie de l'accident de la navette spatiale Challenger
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La chronologie de la mission STS-51-L est la chronologie détaillée des événements depuis l'allumage des moteurs principaux de challengers jusqu'à la destruction des deux propulseurs d'appoint à poudre, et comprend une transcription des conversations de l'équipage à partir de l'enregistreur de voix (Cockpit Voice Recorder) à bord de l'Orbiteur.
STS-51-L était le vingt-cinquième vol du programme navette spatiale, marqué par le premier vol civil à bord de la navette spatiale. La mission utilisait la navette spatiale Challenger, qui a décollé de l'aire de lancement 39B du Centre spatial Kennedy, en Floride en 1986. La mission s'est terminée en catastrophe, par la destruction de Challenger 73 secondes après le décollage en raison de la défaillance d'un joint torique sur le propulseur d'appoint à poudre de droite de Challenger, ce qui a conduit à la désintégration rapide de la navette en raison de l'écrasante pression aérodynamique resultante. Les sept membres de l'équipage ont été tués peu de temps après l'éclatement du véhicule.Légende
Voici la légende des acronymes utilisés :
- APU - Auxilixary Power Unit, générateur auxiliaire
- ET - External Tank, le réservoir externe
- GPC - General Purpose Computer, ordinateur principal
- HPFT - High Pressure Fuel Turbopump, pompe à carburant hautement pressurisée
- LH2 - Liquid Hydrogen, hydrogène liquide
- LO2 ou LOX - Liquid Oxygen, oxygène liquide
- MEC - Main Engine Controller, contrôleur du moteur principal
- PIC - Pyrotechnics Initiator Controller, contrôleur de la pyrotechnie
- psf - Pounds per square foot, pounds par pied au carré
- psi - Pounds per square inch, pounds par inch au carré
- RCS - Reaction Control System, système de contrôle
- CVR - Cockpit Voice Recorder, enregistreur de l'habitacle de la navette
- MET - Mission Elapsed Time, temps en secondes depuis le décollage
Chronologie
Temps (UTC) (heure:minute:seconde) Mission Elapsed Time (MET) (en secondes) Évènement Source 16:37:53.444 -6.566 Commande d'ignition du SSME-3. GPC 16:37:53.564 -6.446 Commande d'ignition du SSME-2. GPC 16:37:53.684 -6.326 Commande d'ignition du SSME-1. GPC 16:37:54 -6 CDR: "There they go guys!" MS2: "All right!" CDR: "Three at a hundred."
CVR 16:38:00 0 MS2 "Aall riight!" CVR 16:38:00.010 0.000 Commande d'ignition du SRB. GPC 16:38:00.018 0.008 Holddown Post 2 PIC firing. Appareil photographique E8 16:38:00.260 0.250 First continuous vertical motion. Appareil photographique E9 The O-rings in the right-hand SRB field joint fail. 16:38:00.688 0.678 First confirmed puff of smoke appears above SRB/ET attachment ring field joint on right-hand SRB. Appareil photographique E60 16:38:00.846 0.836 Eight puffs of smoke appear above field joint, lasting from t+0.836 to t+2.5 seconds MET. Appareil photographique E63 16:38:01 1 PLT "Here we go." CVR 16:38:02.743 2.733 Dernière preuve de fumée provenant du joint. Appareil photographique CZR-1 A solid-fuel 'plug' seals the gap formed by the O-ring 'blow-by'. 16:38:03.385 3.375 Dernière preuve de fumée. Appareil photographique E60 16:38:04.349 4.339 SSMEs throttled up to 104% E41M2076D 16:38:05.684 5.674 Right-hand SRB pressure 11.8 psi above normal. B47P2302C 16:38:07 7 CDR: "Houston, Challenger - Roll program." CVR 16:38:07.734 7.724 Roll program initiated. V90R5301C 16:38:11 11 PLT: "Go you Mother!" CVR 16:38:14 14 MS1: "LVLH" CVR 16:38:15 15 MS2: "(Expletive) hot!" CVR 16:38:16 16 CDR: "Ooohh-kaaay." CVR 16:38:19 19 PLT: "Looks like we've got a lotta wind here today." CVR 16:38:19.869 19.859 SSMEs throttled back to 94% E41M2076D 16:38:20 20 CDR: "Yeah." CVR 16:38:21.134 21.124 Roll program completed. VP0R5301C 16:38:22 22 CDR: "It's a little hard to see out my window here." CVR 16:38:28 28 PLT: "There's ten thousand feet and Mach point five." CVR 16:38:30 30 [Garble] CVR 16:38:35 35 CDR: "Point nine." CVR 16:38:35.389 35.379 SSMEs throttled back to 65% E41M2076D 16:38:37.000 36.990 Roll and Yaw Attitude Response to wind shear (36.990 to 62.990 sec). V95H352nC The solid fuel 'plug' is dislodged. 16:38:40 40 PLT: "There's Mach one." CVR 16:38:41 41 CDR: "Going through nineteen thousand." CVR 16:38:43 43 CDR: "OK, we're throttling down." CVR 16:38:51.870 51.860 SSMEs throttled up to 104% E41M2076D 16:38:57 57 CDR: "Throttling up." CVR 16:38:58 58 PLT: "Throttle up." CVR 16:38:58.798 58.788 First evidence of flame on right-hand SRB. Appareil photographique E207 16:38:59 59 CDR: "Roger." CVR 16:38:59.010 59.000 Reconstructed Max Q (720 psf) Best estimated trajectory 16:38:59.272 59.262 Continuous well defined plume of flame on right-hand SRB. Appareil photographique E207 16:38:59.763 59.753 Flame from right-hand SRB in downwards direction (seen from south side of vehicle). Appareil photographique E204 16:38:60 60 PLT: "Feel that mother go!" "Woooohoooo!"
CVR 16:39:00.014 60.238 Pressures in right- and left-hand SRBs begin to diverge. B47P2302 16:39:00.248 60.238 First evidence of intermittent plume deflection. Appareil photographique E207 16:39:00.258 60.248 First evidence of SRB plume attaching to ET ring frame. Appareil photographique E203 16:39:00.998 60.988 First evidence of continuous plume deflection. Appareil photographique E207 16:39:01.734 61.724 Peak roll rate in response to wind shear. V90R5301C 16:39:02 62 PLT: "Thirty-five thousand going through one point five." CVR 16:39:02.094 62.084 Peak TVC response to wind shear. B58H1150C 16:39:02.414 62.404 Peak yaw response to wind shear. V90R5341C 16:39:02.494 62.484 Right-hand outboard elevon actuator hinge moment spike. V58P0966C 16:39:03.934 63.924 RH outboard elevon actuator delta pressure change. V58P0966C 16:39:03.974 63.964 Start of planned pitch rate manoeuvre. V90R5321C The plume of flame burns through the LH2 tank in the ET. 16:39:04.670 64.660 Change in anomalous plume shape (LH2 tank leak near 2058 ring frame). Appareil photographique E204 16:39:04.715 64.705 Bright sustained glow on sides of ET Appareil photographique E204 16:39:04.947 64.937 Start SSME gimbal angle large pitch variations V58H1100A 16:39:05 65 CDR: "Reading four eighty six on mine." CVR 16:39:05.174 65.164 Beginning of transient motion due to changes in aero forces due to plume. V90R5321C 16:39:06.774 66.764 Start ET LH2 ullage pressure deviations. T41P1700C 16:39:07 67 PLT: "Yep, that's what I've got, too." CVR 16:39:10 70 CDR: "Roger, go at throttle up." (Last transmission on air-to-ground voice loop). CVR The flame burns through the lower attachment strut on the right-hand SRB, causing the SRB to move away from the ET. 16:39:12.214 72.204 Left- and right-hand SRB yaw rates begin to diverge. V90R2528C 16:39:12.294 72.284 Left- and right-hand SRB pitch rates begin to diverge. V90R2525C 16:39:12.488 72.478 SRB major high-rate actuator command. V79H2111A 16:39:12.507 72.497 SSME roll gimball rates 5 deg/sec. V58H1100A 16:39:12.535 72.525 Vehicle max +Y lateral acceleration (+.227 g). V98A1581C 16:39:12.574 72.564 SRB major high-rate actuator motion. B58H1151C 16:39:12.574 72.564 Start of H2 tank pressure decrease with 2 flow control valves open. T41P1700C 16:39:12.634 72.624 Last state vector downlinked. Data reduction 16:39:12.974 72.964 Start of sharp MPS LOX inlet pressure drop. V41P1330C 16:39:13 73 PLT: "Uh-oh..." CVR 16:39:13.020 73.010 Last full computer frame of TDRS data. Data reduction 16:39:13.054 73.044 Start of sharp MPS LH2 inlet pressure drop. V41P1100C 16:39:13.055 73.045 Vehicle max -Y lateral accelerarion (-.254 g). V98A1581C Challenger begins to disintegrate. 16:39:13.134 73.124 Circumferential white pattern on ET aft dome (LH2 tank failure). The bottom of the ET is open and liquid hydrogen spills. Appareil photographique E204 16:39:13.134 73.124 Right-hand SRB pressure 19 psi lower than left-hand SRB B47P2302C 16:39:13.147 73.137 First hint of vapour at intertank. Appareil photographique E207 16:39:13.153 73.143 All engine systems start responding to loss of fuel and LOX inlet pressure. SSME team 16:39:13.172 73.162 Sudden cloud along ET between intertank and aft dome. The right booster slams into the ET just as the LH2 tank is thrust into the oxygen tank. Appareil photographique E207 16:39:13.201 73.191 Flash between Orbiter & LH2 tank. Appareil photographique E204 16:39:13.221 73.211 SSME telemetry data interference from 73.211 to 73.303. Data reduction 16:39:13.223 73.213 Flash near SRB forward attachment strut and brightening of flash between Orbiter and ET Appareil photographique E204 16:39:13.292 73.282 First indication intense white flash at SRB fwd attach point. Appareil photographique E204 16:39:13.337 73.327 Greatly increased intensity of white flash. Appareil photographique E204 16:39:13.387 73.377 Start of RCS jet chamber pressure fluctuations. V42P1552A 16:39:13.393 73.383 All engines approaching HPFT discharge temp redline limits. E41Tn010D 16:39:13.492 73.482 ME-2 HPFT discharge temperature. Channel A votes for shutdown; 2 strikes on Channel B. MEC data 16:39:13.492 73.482 SSME-2 controller last time word update. MEC data 16:39:13.513 73.503 SSME-3 in shutdown due to HPFT discharge temperature redline exceedance. MEC data 16:39:13.513 73.503 SSME-3 controller last time word update. MEC data 16:39:13.533 73.523 SSME-1 in shutdown due to HPFT discharge temperature redline exceedance. Calculation 16:39:13.553 73.543 SSME-1 last telemetered data point. Calculation 16:39:13.628 73.618 Last validated Orbiter telemetry measurement. V46P0120A 16:39:13.641 73.631 End of last reconstructured data frame with valid synchronization and frame count. Data reduction 16:39:14.140 74.130 Last radio frequency signal from Orbiter Data reduction Loss of downlink - Challenger is lost. 16:39:14.597 74.587 Bright flash in vicinity of Orbiter nose. Appareil photographique E204 16:39:16.447 76.437 Right-hand SRB nose cap separation & parachute deployment. Appareil photographique E207 16:39:50.260 110.250 Destruction of right-hand SRB via Range Safety System. E202 Camera. 16:39:50.262 110.252 Destruction of left-hand SRB via Range Safety System. Appareil photographique E230 Notes et références
- (en) Cet article est partiellement ou en totalité issu de l’article de Wikipédia en anglais intitulé « STS-51-L Mission timeline » (voir la liste des auteurs)
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