The Challenger was a shuttle that was launched on January 28, 1986 at 11:38am EST. It had a crew of seven people. They had a planned objective of deploying satellites that were designed to track and observe Halleys comet. There were other mission objectives, one which involved something called, "Teacher in Space Project".

Sharon Christa McAuliffe was a public school teacher, who was trained by NASA, and accompanying the astronauts. It was part of a program NASA started to help educate children about space exploration.

This was to be a historic shuttle launch, and schoolchildren around the nation sat in their classrooms and watched. Unfortunatly, what they saw was a tragedy. Not even 90 seconds after liftoff, the shuttle exploded. All on board were killed.

Where were you when the Space Shuttle Challenger exploded? has become the This question is the "Where were you when Kennedy was shot?", for a generation.

This is a official report off of NASA's webpage about what exactly went wrong with the launch, and caused the explosion.
Just after liftoff at .678 seconds into the flight, photographic data show a strong puff of gray smoke was spurting from the vicinity of the aft field joint on the right Solid Rocket Booster. Computer graphic analysis of film from pad cameras indicated the initial smoke came from the 270 to 310-degree sector of the circumference of the aft field joint of the right Solid Rocket Booster. This area of the solid booster faces the External Tank. The vaporized material streaming from the joint indicated there was not complete sealing action within the joint.

Eight more distinctive puffs of increasingly blacker smoke were recorded between .836 and 2.500 seconds. The smoke appeared to puff upwards from the joint. While each smoke puff was being left behind by the upward flight of the Shuttle, the next fresh puff could be seen near the level of the joint. The multiple smoke puffs in this sequence occurred at about four times per second, approximating the frequency of the structural load dynamics and resultant joint flexing. As the Shuttle increased its upward velocity, it flew past the emerging and expanding smoke puffs. The last smoke was seen above the field joint at 2.733 seconds. The black color and dense composition of the smoke puffs suggest that the grease, joint insulation and rubber O-rings in the joint seal were being burned and eroded by the hot propellant gases.

At approximately 37 seconds, Challenger encountered the first of several high-altitude wind shear conditions, which lasted until about 64 seconds. The wind shear created forces on the vehicle with relatively large fluctuations. These were immediately sensed and countered by the guidance, navigation and control system. The steering system (thrust vector control) of the Solid Rocket Booster responded to all commands and wind shear effects. The wind shear caused the steering system to be more active than on any previous flight.

Both the Shuttle main engines and the solid rockets operated at reduced thrust approaching and passing through the area of maximum dynamic pressure of 720 pounds per square foot. Main engines had been throttled up to 104 percent thrust and the Solid Rocket Boosters were increasing their thrust when the first flickering flame appeared on the right Solid Rocket Booster in the area of the aft field joint. This first very small flame was detected on image enhanced film at 58.788 seconds into the flight. It appeared to originate at about 305 degrees around the booster circumference at or near the aft field joint.

One film frame later from the same camera, the flame was visible without image enhancement. It grew into a continuous, well-defined plume at 59.262 seconds. At about the same time (60 seconds), telemetry showed a pressure differential between the chamber pressures in the right and left boosters. The right booster chamber pressure was lower, confirming the growing leak in the area of the field joint.

As the flame plume increased in size, it was deflected rearward by the aerodynamic slipstream and circumferentially by the protruding structure of the upper ring attaching the booster to the External Tank. These deflections directed the flame plume onto the surface of the External Tank. This sequence of flame spreading is confirmed by analysis of the recovered wreckage. The growing flame also impinged on the strut attaching the Solid Rocket Booster to the External Tank.

The first visual indication that swirling flame from the right Solid Rocket Booster breached the External Tank was at 64.660 seconds when there was an abrupt change in the shape and color of the plume. This indicated that it was mixing with leaking hydrogen from the External Tank. Telemetered changes in the hydrogen tank pressurization confirmed the leak. Within 45 milliseconds of the breach of the External Tank, a bright sustained glow developed on the black-tiled underside of the Challenger between it and the External Tank.

Beginning at about 72 seconds, a series of events occurred extremely rapidly that terminated the flight. Telemetered data indicate a wide variety of flight system actions that support the visual evidence of the photos as the Shuttle struggled futilely against the forces that were destroying it.

At about 72.20 seconds the lower strut linking the Solid Rocket Booster and the External Tank was severed or pulled away from the weakened hydrogen tank permitting the right Solid Rocket Booster to rotate around the upper attachment strut. This rotation is indicated by divergent yaw and pitch rates between the left and right Solid Rocket Boosters.

At 73.124 seconds,. a circumferential white vapor pattern was observed blooming from the side of the External Tank bottom dome. This was the beginning of the structural failure of hydrogen tank that culminated in the entire aft dome dropping away. This released massive amounts of liquid hydrogen from the tank and created a sudden forward thrust of about 2.8 million pounds, pushing the hydrogen tank upward into the intertank structure. At about the same time, the rotating right Solid Rocket Booster impacted the intertank structure and the lower part of the liquid oxygen tank. These structures failed at 73.137 seconds as evidenced by the white vapors appearing in the intertank region.

Within milliseconds there was massive, almost explosive, burning of the hydrogen streaming from the failed tank bottom and liquid oxygen breach in the area of the intertank.

At this point in its trajectory, while traveling at a Mach number of 1.92 at an altitude of 46,000 feet, the Challenger was totally enveloped in the explosive burn. The Challenger's reaction control system ruptured and a hypergolic burn of its propellants occurred as it exited the oxygen-hydrogen flames. The reddish brown colors of the hypergolic fuel burn are visible on the edge of the main fireball. The Orbiter, under severe aerodynamic loads, broke into several large sections which emerged from the fireball. Separate sections that can be identified on film include the main engine/tail section with the engines still burning, one wing of the Orbiter, and the forward fuselage trailing a mass of umbilical lines pulled loose from the payload bay.

The Explosion 73 seconds after liftoff claimed crew and vehicle. Cause of explosion was determined to be an O-ring failure in right SRB. Cold weather was a contributing factor. Launch Weight: 268,829 lbs.
Morton Thiokol made the Solid Rocket Boosters. The problems that caused the disaster were known within the company for some time before the launch. One memo , from Roger Boisjoly on (July 31, 1985) read in part:

"If the same scenorio should occur in a field joint (and it could), then it is a jump ball as to the success or failure of the joint because the secondary O-ring cannot respond to the clevis opening rate and may not be capable of pressurization. The result would be a catastrophe of the highest order--loss of human life."

The night before launch, NASA had a teleconference with Morton Thiokol engineers and executives. The engineers told NASA that it was unsafe to launch in the cold temperature. NASA really wanted to launch. The executives put NASA on hold, and, without the engineers, made a list of reasons why it was safe to launch. When the engineers tried to explain to the executives why it was not safe, they were ignored. The executives then gave NASA the list of reasons that it was safe to launch. They were not questioned.

After the disaster, management at Morton Thiokol harrassed Boisjoly and other engineers for telling the congressional investigation this. Boisjoly sued under various federal and state statutes, and lost.

Sources: http://onlineethics.org/essays/shuttle/bois.html?text
Westlaw.
I was told by Bill Gates that his online handle is Challenger. He frequents a lot of online bridge sites, and that is where he uses it most. He is one of the most watched ametuers in bridge (online at least). Mr. Gates professed to me in our conversation (about many topics) that he is not bad in his own respect, but gets beaten soundly against many professionals.

I had the pleasure of this and several other conversations with him over a period of two years while I worked there as an intern. There is a lot of mystique surrounding the richest man in the world; it was quite an interesting evening.
Challenger
Orbiter OV-099
See also Space Transportation System and space shuttle
This orbiter was destroyed.

Entered service April 4, 1983.
Destroyed January 28, 1986, during its 10th mission.

Flights:
    STS-6    04/04/83
    STS-7    06/18/83
    STS-8    08/30/83
    STS-41B    02/03/84
    STS-41C    04/06/84
    STS-41G    10/05/84
    STS-51B    04/29/85
    STS-51F    07/29/85
    STS-61A    10/30/85
    STS-51L    01/28/86

When Rockwell was granted the contract to build orbiters for the Space Transportation System, two static test articles and two operational orbiters were approved for construction. The second of the two operational shuttle orbiters was Columbia, designated OV-102. The first was Enterprise, OV-101, which had been built for approach and landing tests. The original plan was to convert Enterprise to a fully operational orbiter, thus fulfilling the contract. However, in 1978, a decision was made to not modify OV-101, leaving Columbia the only operational orbiter vehicle. Challenger was built from one of the two static test articles, STA-099. This is the reason for Challenger's unusual designation: OV-099.

Challenger had a special modification in its payload bay which would allow it to carry a Centaur launch vehicle upper stage into orbit. This involved adding extra fuel piping into the bay, since the Centaur upper stage has a liquid-fuel rocket engine, as well as controls in the aft deck to control and monitor the rocket. Discovery has the same modification, but this has since been deemed to risky and there are no plans to use this functionality.

In one of the most tragic accidents in the history of the United States space program, Challenger was lost on January 28, 1986. The vehicle was destroyed, and all seven crew members aboard were lost. More detailed information on the accident can be found in some of the above write-ups. Until the loss of Columbia on February 1, 2003, Challenger was the only United States manned spacecraft to be lost during a mission. (Three astronauts were lost in a fire during a training operation during the Apollo program, but not during an actual mission.)

The rest of the orbiter fleet:
Enterprise * Columbia * Discovery * Atlantis * Endeavour

Actually, I don't think NASA really wanted to launch either. It was our fearless leader, Ronald Reagan, who really wanted to launch then because he felt that another delay would "look bad". I remember seeing on 60 Minutes a NASA engineer who, the night before the launch, had spoken to President Reagan about the effect of the cold on the O-rings (which are precisely what failed). Reagan, of course, insisted that the launch go ahead.

Ultimately, it was our own arrogance and Reagan's ego that caused the explosion of the Challenger and the death of its seven crew members.

The NASA report above glosses over one tiny detail however. The explosion at 73 seconds probably did not kill the crew directly. After the remains of the orbiter were recovered from the ocean it was discovered some of the cabin air cylinders were activated; and the only explanation that anyone has come up with for this discovery is that the cylinders were triggered after the explosion, manually.

The implication is that the cabin was depressurising after the explosion, and that one or more of the astronauts were conscious. However at the altitude the accident occurred, air from a cylinder at the ambient pressure is not sufficient to preserve consciousness for long, pure oxygen might have done so, but these cylinders contained pressurised air. It is perhaps a blessing that they had only compressed air in fact since at that point there was nothing anyone could do; the Orbiter had lost a wing during the explosion and was tracked until impact with the sea at about 200 mph; which would have certainly killed any surviving astronauts.

Still, if that isn't depressing enough, it isn't known how big the leak would have been in Challenger, as the debris disintegrated upon impact, but if the leak was small enough, they could have been alive and conscious right to the end. No records exist of the final moments, as the power for the recording devices onboard were lost during the explosion, and no one knows if they were conscious, but it is thought to be unlikely.

Below is the offical transcript release by NASA and has not been altered in anyway (Save for 1 comment). It can be retrieved at http://www.hq.nasa.gov/office/pao/History/ transcript.html


Editorial Note: This is a transcript of the Challenger operational recorder voice tape. It reveals the comments of Commander Francis R. Scobee, Pilot Michael J. Smith, Mission Specialist 1 Ellison S. Onizuka, and Mission Specialist 2 Judith A. Resnik for the period of T-2:05 prior to launch through approximately T+73 seconds when loss of all data occurred. The operational recorder was automatically activated at T-2:05 and normally runs throughout the mission. During the period of the prelaunch and the launch phase covered by the voice tape, Mission Specialist 3 Ronald E. McNair, Payload Specialist 1 S. Christa McAuliffe, and Payload Specialist 2 Gregory B. Jarvis were seated in the middeck and could monitor all voice activity but did not make any voice reports or comments. This transcript was released following the accident on January 28, 1986. A copy of the document is also available in the NASA Historical Reference Collection, History Office, NASA Headquarters, Washington, DC.

TRANSCRIPT OF THE CHALLENGER CREW COMMENTS FROM THE OPERATIONAL RECORDER

CDR..........Scobee

PLT..........Smith

MS 1.........Onizuka

MS 2.........Resnik

(The references to "NASA" indicate explanatory references NASA provided to the Presidential Commission.)

Time Crew Crew

(Min:Sec).........Position Comment

T-2:05............MS 2..... Would you give that back to me?

T-2:03............MS 2..... Security blanket.

T-2:02............MS 2..... Hmm.

T-1:58............CDR..... Two minutes downstairs; you gotta watch running down there?

(NASA: Two minutes till launch.)

T-1:47............PLT..... OK there goes the lox arm.

(NASA: Liquid oxygen supply arm to ET.)

T-1:46............CDR..... Goes the beanie cap.

(NASA: Liquid oxygen vent cap.)

T-1:44............MS 1..... Doesn't it go the other way?

T-1:42............ Laughter.

T-1:39............MS 1..... Now I see it; I see it.

T-1:39............PLT..... God I hope not Ellison.

T-1:38............MS 1..... I couldn't see it moving; it was behind the center screen.

(NASA: Obstructed view of liquid oxygen supply arm.)

T-1:33. .........MS 2..... Got your harnesses locked?

(NASA: Seat restraints.)

T-1:29............PLT..... What for?

T-1:28............CDR..... I won't lock mine; I might have to reach something.

T-1:24............PLT..... Ooh kaaaay.

T-1:04............MS 1..... Dick's thinking of somebody there.

T-1:03............CDR..... Unhuh.

T-59..............CDR..... One minute downstairs.

(NASA: One minute till launch.)

T-52..............MS 2..... Cabin Pressure is probably going to give us an alarm.

(NASA: Caution and warning alarm. Routine occurrence during prelaunch).

T-50..............CDR..... OK.

T-47..............CDR..... OK there.

T-43..............PLT..... Alarm looks good.

(NASA: Cabin pressure is acceptable.)

T-42..............CDR..... OK.

T-40..............PLT..... Ullage pressures are up.

(NASA: External tank ullage pressure.)

T-34..............PLT..... Right engine helium tank is just a little bit low.

(NASA: SSME supply helium pressure.)

T-32..............CDR..... It was yesterday, too.

T-31..............PLT..... OK.

T-30..............CDR..... Thirty seconds down there.

(NASA: 30 seconds till launch.)

T-25............PLT..... Remember the red button when you make a roll call.

(NASA: Precautionary reminder for communications configuration.)

T-23............CDR..... I won't do that; thanks a lot.

T-15..............CDR..... Fifteen.

(NASA: 15 seconds till launch.)

T-6...............CDR..... There they go guys.

(NASA: SSME Ignition.)

MS 2..... All right.

CDR..... Three at a hundred.

(NASA: SSME thrust level at 100% for all 3 engines.)

T+O...............MS 2..... Aaall riiight.

T+1...............PLT..... Here we go.

(NASA: Vehicle motion.)

T+7...............CDR.............Houston, Challenger roll program.

(NASA: Initiation of vehicle roll program.)

T+11..............PLT..... Go you Mother.

T+14..............MS 1..... LVLH.

(NASA: Reminder for cockpit switch configuration change. Local vertical/local horizontal).

T+15..............MS 2..... (Expletive) hot.

T+16..............CDR..... Ooohh-kaaay.

T+19..............PLT..... Looks like we've got a lotta wind here today.

T+20..............CDR..... Yeah.

T+22..............CDR..... It's a little hard to see out my window here.

T+28..............PLT..... There's ten thousand feet and Mach point five.

(NASA: Altitude and velocity report.)

T+30............ Garble.

T+35..............CDR..... Point nine.

(NASA: Velocity report, 0.9 Mach).

T+40..............PLT..... There's Mach one.

(NASA: Velocity report, 1.0 Mach).

T+41..............CDR..... Going through nineteen thousand.

(NASA: Altitude report, 19,000 ft.)

T+43..............CDR..... OK we're throttling down.

(NASA: Normal SSME thrust reduction during maximum dynamic pressure region.)

T+57..............CDR..... Throttling up.

(NASA: Throttle up to 104% after maximum dynamic pressure.)

T+58..............PLT..... Throttle up.

T+59..............CDR..... Roger.

T+60..............PLT..... Feel that mother go.

T+60............ Woooohoooo.

T+1:02............PLT..... Thirty-five thousand going through one point five

(NASA: Altitude and velocity report, 35,000 ft., 1.5 Mach).

T+1:05............CDR..... Reading four eighty six on mine.

(NASA: Routine airspeed indicator check.)

T+1:07............PLT..... Yep, that's what I've got, too.

T+1:10............CDR..... Roger, go at throttle up.

(NASA: SSME at 104 percent.)

T+1:13............PLT..... Uhoh (Noder's note: Some believe this is NASA being prudent, and the words are really, "Oh shit.").

T+1:13.......................LOSS OF ALL DATA.


Below is the highly controversial "continuation" of the final moments of the Challenger crew. It is highly improbably that this is real, as the operation recorder would have run out of power in 20 seconds after loss of power, being that there is no auxilary power/backup for the recorders. One story states that this transcript came from a discussion between a tabloid report and respected Miami Herald journalist Dennis E. Powell (Nominated by the Herald for his reporting on the Challenger disaster.) asking Dennis what might a crew tape sound like.

Still, this ghostly transcript floats around the Internet, it's validity will never be known, as out of respect for the 7 astronauts, NASA has refused to allow access to the audio tapes (This lead to a Supreme Court case in the New York Times v. National Space and Aeronautics Adminstration). If anything it serves as a haunting reminder of the human fixation with death and tragedy.

The sex of the speaker is indicated by M or F.

T+1:15 (M)....... What happened? What happened? Oh God, no - no!

T+1:17 (F)....... Oh dear God.

T+1:18 (M)....... Turn on your air pack! Turn on your air...

T+1:20 (M)....... Can't breathe... choking...

T+1:21 (M)....... Lift up your visor!

T+1:22 (M/F)....... (Screams.) It's hot. (Sobs.) I can't. Don't tell me...God! Do it...now...

T+1:24 (M)....... I told them...I told them...Dammit! Resnik don't...

T+1:27 (M)....... Take it easy! Move (unintelligible)...

T+1:28 (F)....... Don't let me die like this. Not now. Not here...

T+1:31 (M)....... Your arm... no... I (extended garble, static)

T+1:36 (F)....... I'm...passing...out...

T+1:37 (M).......We're not dead yet.

T+1:40 (M)....... If you ever wanted (unintelligible) me a miracle...(unintelligible)...(screams)

T+1:41 (M)....... She's...she's...(garble)...damn!

T+1:50 (M)....... Can't breathe...

T+1:51 (M/F).......(screams) Jesus Christ! No!

T+1:54 (M)....... She's out.

T+1:55 (M)....... Lucky... (unintelligible).

T+1:56 (M)....... God. The water...we're dead! (screams)

T+2:00 (F)....... Goodbye (sobs)...I love you, I love you...

T+2:03 (M)....... Loosen up...loosen up...

T+2:07 (M)....... It'll just be like a ditch landing...

T+2:09 (M)....... That's right, think positive.

T+2:11 (M)...... Ditch procedure...

T+2:14 (M)....... No way!

T+2:17 (M)....... Give me your hand...

T+2:19 (M)....... You awake in there? I... I...

T+2:29 (M)....... Our Father... (unintelligible)...

T+2:42 (M)....... hallowed be Thy name... (unintelligible).

T+2:58 (M)....... The Lord is my shepherd, I shall...not want. He maketh me to lie down in green pastures... though I walk through the valley of the shadow of death, I will fear no evil... I will dwell in the house...

T+3:15 to end.......None. Static, silence.

Chal"len*ger (?), n.

One who challenges.

 

© Webster 1913.

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