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NASA Shuttle Specific Sections => Shuttle History - Pre-RTF => Topic started by: Chris Bergin on 11/30/2005 05:21 PM

Title: Challenger STS-51L
Post by: Chris Bergin on 11/30/2005 05:21 PM
The main thread (edited to remove old dead links, etc) for STS-51L.

Main articles:
http://www.nasaspaceflight.com/?s=51L
Title: Re: Challenger STS-51L
Post by: Space101 on 11/30/2005 08:18 PM
Where was everyone when it happened? I was just a little kid, but I remember the newsflash as it interupted a kids show I was watching.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 11/30/2005 09:55 PM
Quote
Space101 - 30/11/2005  9:18 PM

Where was everyone when it happened? I was just a little kid, but I remember the newsflash as it interupted a kids show I was watching.

I remember it really well, even though I didn't see the launch live.

I was doing a paper round (as a young kid, obviously) and after I got back to the newsagents at the end of the round I heard two people say in the shop, with one saying to the other "Shit! The Space Shuttle's just exploded" (the shop had a radio on all the time and I assume they heard it over that).

I got home five minutes later and my Mum had Channel 4 or ITV on (I know it was ITN News), which was showing the live pictures of the downrange over the Atlantic, with debris splashing into the sea. They then showed a parachute - which the TV commentator was raising false hopes it was one of the crew. Someone must have corrected him as he then said he was told it was a paramedic dropping in.

Anyway, my previous experiences of Shuttles was only from making an airfix model of Columbia with my Dad - a big Apollo fan - a few years before (sadly not flight worthy for long after my younger brother - then a toddler - decided to chew on it).

I was glued to the TV throughout the coverage of the disaster and the next day went to the Library to get some books on the Shuttles. That's when I got hooked and that's actually how it all started for me.
Title: Re: Challenger STS-51L
Post by: Spacely on 11/30/2005 10:00 PM
I saw it live, at home with my mom, as my school started later in the day that week.

It's weird, but before all the current, feverish 'net discussions about NASA's long-term viability and problems with the Shuttle, I remember America being really into the program. The whole 81-86 time was a sort of NASA silver age. Anyway, I saw the "event" live. I don't recall being particularly devastated; just sort of numbed and thinking "this is big." My parents took it pretty hard.

To this day I still have the Challenge toy set that I had gotten sometime around 1984.
Title: Re: Challenger STS-51L
Post by: Flightstar on 11/30/2005 10:14 PM
There was a feeling it was coming. We were under more and more pressure and people were starting to feel like machines. This was 84, 85 and then they were looking to launch around 11 missions in 86. I didn't watch the launch for the first time. I went home the day before as the next day I wasn't in. I didn't have the TV on or the radio on but it wasn't long before a neighbor came over and I knew right away from the look on his face. I remember feeling furious, rather than sad. I don't want to say too much.
Title: Re: Challenger STS-51L
Post by: SRBseparama on 12/01/2005 01:42 AM
I was too young, but I can only imagine how people must have felt at KSC watching. I also think we should never forget and talk about it because in years to come when it becomes safer, those seven people helped make it so.
Title: Re: Challenger STS-51L
Post by: JamesSpaceFlight on 12/01/2005 12:58 PM
I watched all the launches on TV and this was no different. I remember some concerns about the icing on the pad, but as she lifted of the cheer you could hear reassured me. Then the plume, I remember gasping for a second, then she was gone. Terrible. RIP.
Title: Re: Challenger STS-51L
Post by: Dobbins on 12/01/2005 03:55 PM
I was on a US Navy Cruiser at the San Diego Naval Base. We didn't have cable TV service to the ship, all we had was broadcast TV and the networks weren't covering the launch. As soon as word spread I headed over to the Radio equipment room. The Electronics division was in charge of the Ship's entertainment system and had a set in there so we could monitor the system's operation while standing watch. (at least that was our excuse to have a TV in a work space).

My first reaction was shock. Then white hot anger because I was sure the launch had been pushed under unfavorable conditions so President Reagan could brag about the Teacher in Space during his State of the Union address that was scheduled for that night.

Title: Re: Challenger STS-51L
Post by: t walker on 12/01/2005 05:24 PM
Quote
Chris Bergin - 30/11/2005  10:55 PM

I was glued to the TV throughout the coverage of the disaster and the next day went to the Library to get some books on the Shuttles. That's when I got hooked and that's actually how it all started for me.

I wasn't born when Challenger went, but I have a similar story to the above with STS-107. I was interested in space since the late 90s but when I ran downstairs and saw the Columbia news on ceefax I checked through all of the news channels for many days after and looked it up on the internet. It was then I got hooked on Shuttles specificly as a vehicle.
Title: Re: Challenger STS-51L
Post by: Dana on 12/03/2005 09:54 AM
I was in 8th grade. The school was just a little rural junior-high school called Pleasant View, which isn't in operation anymore. It was right across my grandfather's carrot  field from my house. My homeroom teacher was Mr. Beck, who had taught almost every member of my immediate family except my grandparents. He was a really cool teacher-everybody liked him. (I'll always remember the time a substitute teacher sat down at his desk during homeroom and started looking for a stapler, opened the desk drawer, and found a HUGE bag of gummi worms in there.) He had a great sense of humor and he was also the aerospace teacher and a private pilot. He was the one who insisted that our library have books and magazines about airplanes and spaceflight. Having a lifelong fascination with flying and spaceflight even then, I was glad I was in his class.

It was his birthday.

Our class had a birthday party for him in homeroom period that morning. We had cake and cookies and kool-aid. We had a cassette player playing tunes. Everybody was having fun.

After a while, Mr. Beck happened to look out and spot a group of teachers gathered at the door of the principal's office down the hall, and excused himself to go see what was going on. He barely got to the door before some other teacher walked up and knocked on it, and off they went. The party went on.

A few minutes later, he walked in and leaned back on the front of his desk. He called for everyone's attention. "Everybody, I have some bad news, please listen. I was just over watching TV in Mr. Kaiser's office. The Space Shuttle just exploded."

We didn't believe it at first. Pleasant View had 2 7th grade classrooms and 2 8th grade classrooms, a grand total of about 60 or 70 kids, and we all crammed into the library, which was the biggest room where you could plug in a TV. The first thing we saw was footage of pieces splashing into the Atlantic ocean, obviously taken with a powerful zoom lense. It didn't hit home for us until CBS showed the explosion itself. An audible gasp went through us, and we just sat there, staring. I was sitting next to a girl named Melissa Ashby, a 7th-grader who kind of liked me and who I kind of liked back, and she grabbed my hand.

I think we were just barely old enough to really get it. Most of us were 13 or 14, and had the most vague childhood memories of Skylab and ASTP; I can very vauguely remember my uncle Wade carrying me outside one cold night and pointing up at the Moon and telling me there were guys walking on it as we spoke, which in retrospect must have been Apollo 17. But I did remember Skylab, and ASTP, most of us were born in the era of capsules and splashdowns and knew how special and amazing a machine the Shuttle Orbiter was. Just as the kids who grew up in the '60s could follow the Gemini and Apollo missions, we had grown up with the Shuttle. We had been in 2nd or 3rd grade in 1981 when the first mission flew, and my 3rd grade class even had a writing assignment about it, which I still have someplace. The Shuttle was ours.

And it hurt.

I held Melissa's hand for a few minutes until a teacher spotted us and told us to stop, and we watched for about a half hour until the start of the next period. We had to go to the next class, which for me was english. But I didn't last 5 minutes. I became physically ill. I started crying. I just got up and left, put on my heavy blue coat and went home, walking across the field. (We didn't need to lock our doors way out there, at least not back then.) My mom, a single parent, worked for the Veteran's Administration hospital up in Walla Walla, WA, and somebody, probably Mr. Beck now that I think about it, called her. Apparently he didn't tell her anything about why I went home, except something like, "....which I guess is understandable today," thinking she knew. When she called home, I was sitting there in the dark with my big Calico cat, crying. She was pretty mad. "Why did you go home from school?" she wanted to know.

"What do you mean why? Don't you know what happened?"

"No, what?"

Then I told her. And she said, "Oh, honey, I'm sorry." She knew what it would mean to me-I was the only kid in the 8th grade who had his own copy of "The Right Stuff" and all-and just told me to get something to eat and maybe lay down for a while. It really got to me. It was one of those moments that I will always remember where I was, along with September 11th, 2001, and February 2, 2003. I wish my generation could have a memory like these, a date and event that you remember where you were and what you were doing when you heard about it, that was positive, inspiring, like V-J Day or Apollo 11 had been. But by and large, we really don't.

Challenger exploded in the middle of my 8th grade year. I was a junior in high school before we flew in space again.  
Title: Re: Challenger STS-51L
Post by: STS Tony on 12/03/2005 08:46 PM
I was going to go to one of the many launches they had planned for that year. I was really looking forward to it and followed the last few missions before Challenger closely. Could not believe what I was seeing when they showed the launch go wrong. Don't think it sunk in for many days later when they had the memorial service and we saw the familes. Very sad.
Title: Re: Challenger STS-51L
Post by: GregM on 12/04/2005 07:50 AM
I wasn’t a kid when the 51-L accident occurred. Watched it happen with my college roommate on that January morning. Maybe I could add a few personal recollections.

I was an avid spaceflight researcher at that time. In the months leading up to January of 86, myself and others I knew who were following the shuttle program were getting a…  well… a vibe would be the best way to describe it. Although it would be impossible to verbalize, it was essentially a feeling of dread during launches. I think it came down to a vague  sensation that there wasn’t a firm grip on every aspect of the program - that things were moving too fast. I got so bothered by this intangible feeling that by November of 1985, just a few seconds after watching STS-23 leave the pad - I shut off the television.  I could not bear to watch the powered ascent; the sense of dread in me was so strong. I had viewed every other shuttle launch up to that point with great enthusiasm. For whatever reason, my whole demeanor changed in the autumn of ‘85 though. My main fear was not such a sudden catastrophic event as what happened in 51-L however, it  rather was the much feared RTLS abort generated by multiple SSME failures.

When 51-L did break up, I would describe it in one way – surreal. That type of sudden catastrophic failure was generally not considered very much at the time (at least publicly) in launch abort planning. To see a launch failure of that nature happen on a shuttle launch was simply very unexpected. At the time there was in the public the expectation that this sort of  scenario was just not very likely, especially when NASA gave odds of such an occurrence to be something like 4700 to one, or some such thing. In any event, when it did happen, it didn’t seem real at first. My second reaction after about 20 seconds of astonishment was wondering (and hoping) if they had ever attached a recovery parachute package to the crew cabin, which I knew would likely emerge intact from the disintegrating airframe of Challenger, and the fireball engulfing the melee. I had never heard of such a feature, but hoped that maybe I had missed something in my research on the shuttle system. I knew that the ESA was planning to install just such a system in their upcoming shuttle, Hermes. I knew in my heart that it was very unlikely however, as I knew the STS system fairly well.  Of course nobody was rescued from the ocean. The biggest impression that I got from the telephoto television cameras on top of the VAB scanning the Atlantic in vain for survivors was the force of impact that was generated by the larger pieces of debris. Huge splashes could be seen in the water from 20 or 30 miles away from shore.

Initially, nobody would even hazard a guess as to why the accident occurred. The video feed of the launch at the time gave very little evidence of any problem, and NASA was not releasing anything else – in fact pretty much everything had been impounded. About a week after the accident, NASA publicly released a 5 second or so clip of  film taken by a ground tracking camera from a viewpoint directly behind the ascending shuttle stack. They released the film with no comment. The now-legendary tongue of flame emerging from the side of one of  the SRB’s could clearly be seen lapping onto the SRB attach strut and external tank. Things came together pretty fast after that as to what happened in a superficial sense. Talk of heated teleconferences, cold weather, and o-rings would come much later however.

The basics of what happened came down to this publicly known information:

The o-rings that were intended to seat themselves in the SRB field joints with internal SRB ignition pressures did not seat properly because they were too cold and brittle. The air temperature on the eve of launch was well below freezing. Combustion gasses leaked through an improperly sealed field joint. Smoke from burning lubrication grease, o-ring, and SRB fuel can be seen spewing out of the side of the SRB at the field joint seconds after the vehicle left the pad. Challenger was doomed from that moment.

Very quickly, the leak allowed more and more combustion gas to leak out of the side of the SRB. By 30 or 40 seconds after launch, the leak of flame was huge - like a giant blowtorch against the SRB attach strut and the aft of the external tank. This was causing two things to happen: Firstly, the vehicle was trying to rotate because of was what was in essence a new sideways-pointed rocket engine. The Challenger gimbaled her SSME’s hard opposite to counter this new force trying to steer her off course and off attitude. Secondly, the huge tongue of flame lapping against the external tank was greatly increasing pressures inside the hydrogen tank portion of the module.

At the one minute point, several things happened near simultaneously. Firstly, the torched SRB rear attach strut finally broke apart, releasing the rear of the SRB. The rear of the SRB proceeded to rotate outward from the ascending vehicle, while still attached at the front attach point with the external tank. This essentially placed the errant SRB in a configuration to drive itself into the side of the external tank just above the still functioning forward attach point. This is also the intertank separation space between the oxygen and hydrogen tank on the SRB. The SRB proceeded to do just that, and drive itself into the side of the ET. Pilot Mike Smith probably saw this happening when he uttered “uh oh” – the last transmitted words received from Challenger. Because this was the intertank separation location, the SRB simultaneously ruptured both the bottom of the oxygen tank and the top of the hydrogen tank, as it was proceeding to tear the external tank in half. This was not the full story however. Remember that the hydrogen tank is now super pressurized and near the rupturing point due to the bottom portion being heated up by the blowtorch effect of the flame leaking out of the side SRB onto the bottom and side of the external tank. The bottom of the external tank, which is also the bottom of the hydrogen tank, is an inverted dome structure. This dome structure has also been significantly structurally weakened as well, as a result of being torched by the SRB flame leak. Now, the SRB comes crashing through the top of the hydrogen tank. The rear of the hydrogen tank can’t take it any more. The aft dome blows apart due to being structurally weakened, and the stresses from an already over pressurized tank. Now more pressure gets applied due to the SRB driving itself through the top portion of the tank. That’s it.  Superpressurized liquid hydrogen bursts out of the rear of the external tank and ignites, adding an estimated 3 to 4 million pounds of thrust to the vehicle’s intended 6.5 million pound thrust. For a few seconds, Challenger is riding 10 million pounds of thrust. But it does not last long. Nothing in the shuttle stack is designed for those acceleration loads. Everything falls apart under the sudden acceleration stress. The upper half of the external tank is already in shreds due to the errant SRB driving itself through it, but Challenger itself disintegrates  due to acceleration and aerodynamic loading from the sudden 60% increase in thrust and resultant acceleration to the launch stack. The disintrigating ET has its contents of liquid oxygen and hydrogen suddenly released into the atmosphere and ignited. There is a fuel-air ignition of the materials, but it is not really an explosion. The SRB’s ironically enough just fly away on their own, later shut down by range safety.

So, Challenger was not destroyed in an “explosion”, as much as the media claimed at the time (there were incorrect references to the “explosion” being equivalent to a small a atomic bomb at the time of the accident). There was a fuel-air ignition of the contents of the external tank, but “explosion” would be an improper description of the event. Fuel and oxidizer was released into the atmosphere, and then ignited – producing the fireball seen. Challenger herself however was however torn apart due to the stack suddenly accelerating to something over 10 million pounds of thrust. Turbopumps on the Orbiter’s SSMEs were still running at the time the simultaneous events of the external tank’s front end being torn apart by the errant SRB, the back of the external tank bursting open at its rear and adding 4 million pounds of thrust, and the orbiter itself breaking up. Other than the RCS and OMS modules exploding in the nose and aft of Challenger, the remainder of the Orbiter simply broke up due to acceleration as she flew through the fireball produced by the released contents of the external tank. The key to this reality is that the Orbiter was not blasted to bits, as was originally thought, but rather broke up into primary components.

At the time of the accident, it was originally thought and assumed that the orbiter and crew mercifully met their end at the time of the “explosion”. Much later however, it was learned that there was no real explosion. The Orbiter simply broke up under intolerable acceleration stresses as it hurled through the fireball. The crew cabin was released from Challenger’s disintegrating airframe and exited the fireball relatively intact. Public images show the cabin exiting the fireball, trailing wiring and plumbing from the rear lower portion of the cab. This is where the truly disturbing and tragic implications lie: the crew on the flight deck survived the initial event. What happened on the mid-deck is less certain. It is also common knowledge that Judy Resnik started Dick Scobee’s emergency oxygen pack following the event, and yes there was an onboard flight voice recorder. The very horrifying and tragic conclusion is that after the initial event, at least some of the crew knew what was going on to some degree, and likely grasped the gravity of their situation. It was several minutes of hurling violently but silently through the air before they met the Atlantic. What was said and done in that time that is a private matter. For those who care to, I think that you can imagine it in your minds, and that is enough.

A few parting comments: Astronauts and other folks with a technical background understand the risks of spaceflight, especially the launch phase. Nobody wants to die, but the crewmembers understand the risks and accept the odds. Casualties of this occupation are not victims in any conventional sense. Insurance companies do not sell life insurance to test pilots for a good reason. They could have accepted any number of vocations that have a much lower danger factor, but they did not, still knowing the risks of spaceflight. Space travelers who have lost their life in the line of duty are often referred to in popular media as heroes. This is unfair. Everyone who gets into a spacecraft and launches into the heavens is a hero, because they all know thew the risks and knowingly accept them in the cause of opening up the new frontier. We should have the greatest respect for all of them, whether alive or deceased. The important thing is that they assumed the risk knowingly.

Lives will be lost in this endeavor known as spaceflight, but it will be the unlucky ones who will be those who loose their lives in that endeavor – and we should forever honor them – but every space traveler is a hero in some sense, because all of them take the same risk in the first place,
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/04/2005 02:54 PM
Thank you for sharing, Greg. Very sobering. Welcome to the site.
Title: Re: Challenger STS-51L
Post by: SimonShuttle on 12/04/2005 03:59 PM
You can tell on the "post a picture of yourself" thread that many on here are too young to have a clear memory of this at the time of the accident, but I would like to thank everyone for posting their experience. It's really appreciated and helps us all understand the brave people that are invovled with the dangers of space flight.
Title: Re: Challenger STS-51L
Post by: STS Tony on 12/04/2005 04:36 PM
That's an amazing recolation Greg.

To the UK posters, does anyone have any clips of the UK news coverage of the aftermath?
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/04/2005 04:51 PM
I was kindly sent a VHS video of the ITN coverage with Alistair Stewart of the live news coverage, just a few years ago. I believe he was a new lead anchor at the time for ITN (Which is now main news broadcaster for ITV 1, 2, 3 and Channel 4, Channel 5 and ITN News Channel).

He was brilliant, to say there was so little information coming out.

He went on to become ITN's Washington correspondent for a short while before heading to the Gulf to cover Desert Storm.

I'll try and find that video and see if I can record some of it into a format I can add to the video section.
Title: Re: Challenger STS-51L
Post by: UK Shuttle Clan on 12/04/2005 07:02 PM
Alistair Stewart is one of the best broadcaster in the UK. Him, Jon Snow and Sir Trevor McDonald are the top three I'd say. I was too young to remember the events live, and I didn't know he was the guy who got to do the newsflash special in the minutes after the loss of Challenger. I'd be very interested in any clips, to understand the gravity of how it was reported to the UK.

Maybe he would be interested in giving some comments on the events? We've got people involved with the Shuttle, people who remember hearing/seeing the news, so that would be very fitting to have all angles, given we're heading to the 20th anniversary next month.
Title: Re: Challenger STS-51L
Post by: SimonShuttle on 12/05/2005 07:24 AM
I had no idea Alistair Stewart was the guy that broke the news over here. I know this is slightly off topic, but given the terrible way the UK TV networks (mainly BBC) inaccurately report NASA and Shuttle news, it would have been very important that Alistair Stewart reported the disaster as without seeing it I know he'd of the right man to give such bad news. He's one of the best.
Title: Re: Challenger STS-51L
Post by: nethegauner on 12/05/2005 08:50 AM
Boy, this thread definitly brings back some memories ... :(

I was ten years old. It was a Tuesday and every Tuesday, ZDF of Germany aired an half hour of "Tom and Jerry" cartoons in the late afternoon. That was usually followed by a brief round-up of current news. While watching the cartoon, I was practicing EAFB approaches in my parents' living room, where a beige colored blanket doubled for the Mojave desert. My Challenger toy performed quite well that day. Must have been the umpteeth successful landing in a row that afternoon without a single hitch ...

But when "Tom and Jerry" was over, a full news program started. I was surprised. Why did they not just deliver the banner headlines? Why is there a presenter on screen? It was, of course, because of 51-L. My child's mind could not believe it. I looked at my Chalenger toy and just could not believe it. They showed the explosion, portraits of the crew, televised pre-launch events. We have a saying here: im falschen Film sitzen -- I'm watching the wrong movie here ...

That's how I felt.
Title: Re: Challenger STS-51L
Post by: Justin Space on 12/05/2005 12:29 PM
It's amazing how something terrible can touch people in different parts of the world the same way.
Title: Re: Challenger STS-51L
Post by: Orbiter Obvious on 12/06/2005 10:22 PM
I wasn't born, but does anyone know if NASA will do something special for the 20th Anniversary next year?
Title: Re: Challenger STS-51L
Post by: Avron on 12/07/2005 04:36 AM
I remember it well, was in my car listening to the radio.
Was always concerned that there was no way out for the crew, even if the problem was detected prior to the explosion.
I can remember looking at footage of the launch control center, and at the far side of the room was a TV, and on that TV was realtime footage of teh launch and the SRB plume that is clearly visable to anyone who was watching that TV, the rest of the world where watching the TV picture from another (or more standard view), now if someone had noted the plume from the SRB on the TV, there was no abort button to push.. and still is not..

Stolen from the Rogers report:  (what is most amazing is how the vehicle is trying to keep alive, a no win situation)


38:51.870  SSME 104% Command                   51.860  E41M2076D
   38:58.798  First evidence of flame on RH SRM   58.788  E207 Camera
   38:59.010  Reconstructed Max Q (720 psf)       59.000  BET
   38:59.272  Continuous well defined plume
                    on RH SRM                     59.262  E207 Camera
   38:59.763  Flame from RH SRM in +Z direction
              (seen from south side of vehicle)   59.753  E204 Camera
   39:00.014  SRM pressure divergence (RH vs. LH) 60.004  B47P2302
   39:00.248  First evidence of plume deflection,
                intermittent                      60.238  E207 Camera
   39:00.258  First evidence of SRB  plume
              attaching to ET ring frame          60.248  E203 Camera
   39:00.998  First evidence of plume deflection,
               continuous                         60.988  E207 Camera
   39:01.734  Peak roll rate response to wind     61.724  V90R5301C
   39:02.094  Peak TVC response to wind           62.084  B58H1150C
   39:02.414  Peak yaw response to wind           62.404  V90R5341C
   39:02.494  RH outboard elevon actuator hinge
               moment spike                       62.484  V58P0966C
   39:03.934  RH outboard elevon actuator delta
                pressure change                   63.924  V58P0966C
   39:03.974  Start of planned pitch rate
                maneuver                          63.964  V90R5321C
   39:04.670  Change in anomalous plume shape
              (LH2 tank leak near 2058 ring
              frame)                              64.660  E204 Camera
   39:04.715  Bright sustained glow on sides
               of ET                              64.705  E204 Camera
   39:04.947  Start SSME gimbal angle large
                pitch variations                  64.937  V58H1100A
   39:05.174  Beginning of transient motion due
                to changes in aero forces due to
                plume                             65.164  V90R5321C
   39:06.774  Start ET LH2 ullage pressure
               deviations                         66.764  T41P1700C
   39:12.214  Start divergent yaw rates
               (RH vs. LH SRB)                    72.204  V90R2528C
   39:12.294  Start divergent pitch rates
               (RH vs. LH SRB)                    72.284  V90R2525C
   39:12.488  SRB major high-rate actuator
                command                           72.478  V79H2111A
   39:12.507  SSME roll gimball rates 5 deg/sec   72.497  V58H1100A
   39:12.535  Vehicle max +Y lateral
               acceleration (+.227 g)             72.525  V98A1581C
   39:12.574  SRB major high-rate actuator
              motion                              72.564  B58H1151C
   39:12.574  Start of H2 tank pressure decrease
              with 2 flow control valves open     72.564  T41P1700C
   39:12.634  Last state vector downlinked       72.624 Data reduction
   39:12.974  Start of sharp MPS LOX inlet
              pressure drop                       72.964  V41P1330C
   39:13.020  Last full computer frame of TDRS
                 data                            73.010 Data reduction
   39:13.054  Start of sharp MPS LH2 inlet
              pressure drop                       73.044  V41P1100C
   39:13.055  Vehicle max -Y lateral
                accelerarion (-.254 g)            73.045  V98A1581C
   39:13.134  Circumferential white pattern on
              ET aft dome (LH2 tank failure)      73.124  E204 Camera
   39:13.134  RH SRM pressure 19 psi lower
              than LH SRM                         73.124  B47P2302C
   39:13.147  First hint of vapor at intertank    E207 Camera
   39:13.153  All engine systems start responding
              to loss of fuel and LOX inlet
                pressure                          73.143  SSME team
   39:13.172  Sudden cloud along ET between
              intertank and aft dome              73.162  E207 Camera
   39:13.201  Flash between Orbiter & LH2 tank    73.191  E204 Camera
   39:13.221  SSME telemetry data interference
              from 73.211 to 73.303               73.211
   39:13.223  Flash near SRB fwd attach and
               brightening of flash between
               Orbiter and ET                     73.213  E204 Camera
   39:13.292  First indication intense white
              flash at SRB fwd attach point       73.282  E204 Camera
   39:13.337  Greatly increased intensity of
               white flash                        73.327  E204 Camera
   39:13.387  Start RCS jet chamber pressure
                fluctuations                      73.377  V42P1552A
   39:13.393  All engines approaching HPFT
              discharge temp redline limits       73.383  E41Tn010D
   39:13.492  ME-2 HPFT disch. temp Chan. A vote
             for shutdown; 2 strikes on Chan. B   73.482  MEC data
   39:13.492  ME-2 controller last time word
                update                            73.482  MEC data
   39:13.513  ME-3 in shutdown due to HPFT discharge
              temperature redline exceedance      73.503  MEC data
   39:13.513  ME-3 controller last time word
                 update                           73.503  MEC data
   39:13.533  ME-1 in shutdown due to HPFT discharge
              temperature redline exceedance      73.523  Calculation
   39:13.553  ME-1 last telemetered data point    73.543  Calculation
   39:13.628  Last validated Orbiter telemetry
              measurement                         73.618  V46P0120A
   39:13.641  End of last reconstructured data
              frame with valid synchronization
              and frame count                    73.631 Data reduction
   39:14.140  Last radio frequency signal from
                Orbiter                          74.130 Data reduction
   39:14.597  Bright flash in vicinity of Orbiter
                nose                             74.587  E204 Camera
   39:16.447  RH SRB nose cap sep/chute
                deployment                       76.437  E207 Camera
   39:50.260  RH SRB RSS destruct               110.250  E202 Camera
   39:50.262  LH SRB RSS destruct               110.252  E230 Camera

Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/07/2005 03:03 PM
Yes, same with Columbia on the huge efforts, but Challenger was having a lot more work to do with the SSMES, and the SRBs - even the wings at some point. Impossible situation all the same.
Title: Re: Challenger STS-51L
Post by: SimonShuttle on 12/09/2005 12:32 PM
Was there any way they could have just seperated the boosters as soon as it was seen one was becoming critical, then do a RTLS or even ditch?
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/09/2005 12:49 PM
Well while it really all happened too fast, there's not a lot that can be done.

SRB sep would not of solved the problem with the ET being compromised.

Orbiter sep from the ET and SRBs would have flown the orbiter right into the ET or path of the SRB exhaust.

No win situation I'm afraid :(
Title: Re: Challenger STS-51L
Post by: JamesSpaceFlight on 12/09/2005 01:19 PM
I've looked at the speed of the events, BA was a consultant on senario event investigation for any program the UK would undertake. There was nothing that could have been done. She was literally doomed from the second she left the pad.
Title: Re: Challenger STS-51L
Post by: Orbiter Obvious on 12/09/2005 03:23 PM
Very sad. I'm more shocked about the forcing of the launch for Reagan. Is that comfirmed or is it just rumor?
Title: Re: Challenger STS-51L
Post by: Dobbins on 12/09/2005 03:56 PM
Quote
Orbiter Obvious - 9/12/2005  11:23 AM

Very sad. I'm more shocked about the forcing of the launch for Reagan. Is that comfirmed or is it just rumor?

It's a long standing suspicion that could never be confirmed. NASA doesn't like making Presidents unhappy and making Reagan unhappy is something that would have been in the back of many minds in upper management.

Title: Re: Challenger STS-51L
Post by: Super George on 12/09/2005 04:41 PM
Yes, I think it was based on a rumor that the President wanted to include that a Teacher was able to travel into space on the ship he christened (STS-4 Columbia, end of test flights).

Personally I do not think that would mean NASA was forced to launch and Reagan wouldn't of had anything to do with the risk factor given the blow to the program that it ended up being.

Maybe NASA upper management didn't want to delay for the President, to keep him happy as he was the paymaster at the time. Maybe NASA didn't want to ruin their attempt to have that "year of the Shuttle" after just the second flight.

Whatever it was, it highlighted the arrogance of a time where NASA didn't listen to its contractors or itself when told to launch would be a major risk.
Title: Re: Challenger STS-51L
Post by: Avron on 12/09/2005 10:29 PM
Quote
Super George - 9/12/2005  12:41 PM

Yes, I think it was based on a rumor that the President wanted to include that a Teacher was able to travel into space on the ship he christened (STS-4 Columbia, end of test flights).

Personally I do not think that would mean NASA was forced to launch and Reagan wouldn't of had anything to do with the risk factor given the blow to the program that it ended up being.

Maybe NASA upper management didn't want to delay for the President, to keep him happy as he was the paymaster at the time. Maybe NASA didn't want to ruin their attempt to have that "year of the Shuttle" after just the second flight.

Whatever it was, it highlighted the arrogance of a time where NASA didn't listen to its contractors or itself when told to launch would be a major risk.

And clearly violated the launch constraints...   this is not the same as our current foam issue... IMHO, one was NASA ( upper management) and the the other (foam) was and still is on the head of Lockmart or MSFC... but they seem to be covering each other.. Humm
Title: Re: Challenger STS-51L
Post by: psloss on 12/09/2005 11:00 PM
Quote
Super George - 9/12/2005  12:41 PM

Whatever it was, it highlighted the arrogance of a time where NASA didn't listen to its contractors or itself when told to launch would be a major risk.
There was plenty of schedule pressure, particularly the Centaur launches off both pads during essentially the same week.  But there was also hubris in both shuttle disasters.

Challenger and the 51-L crew were the unlucky ones to be flying when that SRM design failed; however, proverbial bullets had already been dodged -- secondary O-ring erosion in both the case-to-case and the case-to-nozzle joints -- and given the increasing flight rate, I think something was going to break in trying to ramp up to the 24 flights per year they were shooting for back then.  (Possibly something besides the booster field joints.)
Title: Re: Challenger STS-51L
Post by: Ben E on 12/09/2005 11:43 PM
Out of curiosity, what were the realistic chances of achieving the mammoth flight rates envisaged in the early 1980s. Admittedly, the 24-flights-per-year idea was ludicrous, but would NASA have been able to manage, say, the 14 flights planned for 1986. Was the Shuttle programme technically capable of doing it or would it have ended up similar to 1985 with 9-10 flights?

Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/10/2005 08:52 AM
14 flights in 1986? Damn - I thought it was 12 and that was pushing it. I know they wanted to call it the year of the Shuttle, but I had no idea it was 14!
Title: Re: Challenger STS-51L
Post by: psloss on 12/10/2005 12:38 PM
At the beginning of the year, I believe they had these "highlights":

* the Comet Halley ASTRO flight (61-E)
(Challenger was "holding up" Pad B, and Halley wasn't going to wait)

* The two interplanetary, shuttle/Centaur flights -- Ulysses and then Galileo (61-F/61-G)
(Atlantis was getting ready to go out to Pad A for Centaur tanking tests)

* The first Vandenberg launch (62-A)
(and possibly 62-B by the end of the year; that schedule was already slipping.  Perhaps someone here who was at KSC back then would know whether Discovery was going to be ready to support the rest of the pad validations, such as the planned FRF.  She was still at KSC on 28 January.)

* The HST deploy mission (61-J)

That's all I can recall mostly off the top of my head.

-- OK, now I'm cheating with Google: there was also the LDEF retrieval mission, too!  Here's the reference:
http://www.astronautix.com/articles/youelled.htm

Philip Sloss
Title: Re: Challenger STS-51L
Post by: anik on 12/10/2005 12:47 PM
Quote
Chris Bergin - 10/12/2005  12:52 PM

14 flights in 1986?
Maybe 15 flights…

1 – January 12* – Columbia (61-C) – Satcom Ku-1, MSL-2;
2 – January 28* – Challenger (51-L) – TDRS-B, Spartan 203;
3 – March 6 – Columbia (61-E) – Astro-1;
4 – May 15 – Challenger (61-F) – Ulysses;
5 – May 21 – Atlantis (61-G) – Galileo;
6 – June 24 – Columbia (61-H) – Skynet 4A, Palapa B3, Westar 6S;
7 – July – Discovery (62-A) – DoD (Teal-Ruby);
8 – July 15 – Challenger (61-M) – EOS 1, TDRS-C;
9 – September 3 – Atlantis (61-K) – EOM-1/2;
10 – September – Columbia (61-N) – DoD (SDS B-1);
11 – September – Challenger (61-I) – Insat 1C;
12 – September – Discovery (62-B) – DoD (Lacrosse 1);
13 – October – Atlantis (61-J) – HST;
14 – November – Columbia (61-L) – MSL 3, Leasat 5, GStar 3;
15 – December – Challenger (71-B) – DoD (DSP F14).
* – actual launch date

I may have mistakes...
Title: Re: Challenger STS-51L
Post by: Ben E on 12/10/2005 01:32 PM
It's also interesting to see how short the turnaround times were for individual orbiters in the pre-51L timeframe. Are there any reasons (technical or otherwise) how NASA achieved these six-week-to-two-month turnaround times in the 'olden days' and never again routinely achieved this post-51L? It surely can't all have been due to cost-cutting and safety compromises.

I think the post-51L record was just under three months for STS-83/94, but that was just because it was the same payload on both missions. Generally, post-51L turnarounds have averaged four to six months.

Any explanations why?
Title: Re: Challenger STS-51L
Post by: anik on 12/10/2005 02:48 PM
According to http://www.astronautix.com/project/sts.htm

1. Atlantis (61-G) should be launched on May 20 (not on May 21);
2. Challenger (61-M) should be launched on July 22 (not on July 15);
3. Atlantis (61-J) should be launched in August (not in October);
4. 61-N should be launched on Discovery (not on Columbia) on September 4;
5. Challenger (61-I) should be launched on September 27;
6. Discovery (62-B) should be launched on September 29;
7. 61-K should be launched on Columbia (not on Atlantis) in October (not on September 3);
8. 61-L should be launched on Atlantis (not on Columbia).

P.S.: Between Challenger (61-F) and Atlantis (61-G) launches were 5 days!
PP.S.: Between Discovery launches from KSC (61-N) and from VAFB (62-B) were 25 days!
Title: Re: Challenger STS-51L
Post by: David AF on 12/10/2005 04:09 PM
That is amazing. If they had only pulled it off the USAF would not have pulled out and we might have a different story now on the cash.
Title: Re: Challenger STS-51L
Post by: Ben E on 12/10/2005 05:58 PM
I was always under the impression that 61N was actually a Columbia mission and have drawn attention to it in my book SPACE SHUTTLE COLUMBIA. A couple of years ago, I spoke to 61N Commander Brewster Shaw, who told me that at the time of the 51L disaster he was expecting to fly a classified DoD mission aboard Columbia in the autumn. The original 61N crew, minus Pilot Mike McCulley and Payload Specialist Frank Casserino, eventually flew Columbia on STS-28.

I very much doubt that, even in the optimistic pre-51L days, a 25-day turnaround would have been possible, let alone a turnaround which also involved flying from coast to coast to launch from different sites.

I think the all-time turnaround record, actually achieved, was about 51 days for Atlantis on the 51J/61B turnaround, in which she landed from her first mission on October 7th 1985 and next launched on November 27th. Correct me if I'm wrong, but I don't think the Shuttle ever beat that.

Title: Re: Challenger STS-51L
Post by: ADC9 on 12/10/2005 07:20 PM
And they shouldn't be looking to beat it. I'd sooner of seen a less overdone schedule because I honestly think it's a reciepe for disaster.
Title: Re: Challenger STS-51L
Post by: James Lowe1 on 12/10/2005 08:58 PM
Quote
anik - 10/12/2005  9:48 AM

P.S.: Between Challenger (61-F) and Atlantis (61-G) launches were 5 days!

So we'd of had TWO orbiters in space at the same time??
Title: Re: Challenger STS-51L
Post by: Mark Max Q on 12/10/2005 11:15 PM
Looks like it. I cannot think of any reason an Orbiter would be up there for less than five days. Wow.
Title: Re: Challenger STS-51L
Post by: Spacely on 12/11/2005 04:19 AM
Does anybody know what the Jupiter ETA was for Galileo had it been launched in '86 with the Centaur stage?
Title: Re: Challenger STS-51L
Post by: Ben E on 12/11/2005 06:15 AM
I think Galileo's Jupiter ETA would have been about two years later in 1988. It was pretty quick compared to IUS.

No, 61F and 61G wouldn't have been in orbit at the same time. I don't think the Mission Control, existing TDRS and tracking capabilities could have handled that. Both missions were scheduled as two-day missions, because the heavy Centaur and Ulysses/Galileo meant that consumables/equipment/supplies/crew number had to kept to a minimum. I wrote to Dave Hilmers about it back in 1991 and he told me that, ordinarily, four days is the shortest duration for a planned Shuttle mission but that these two in particular were shorter because of weight considerations.

Interestingly, they were also destined for the lowest Shuttle orbits of all time - 105 nautical miles, simply because Centaur was so heavy and they needed the SRB/orbiter performance to simply get it up there.

Have a look at my Death Stars article in Features on this site for a bit more info.



Title: Re: Challenger STS-51L
Post by: SimonShuttle on 12/11/2005 11:52 AM
Ah that's interesting. Yikes, nothing like taking up heavy dangerous stuff in your payload!

http://www.nasaspaceflight.com/content/?id=3943
Title: Re: Challenger STS-51L
Post by: psloss on 12/11/2005 12:28 PM
Another "fun" thing about the shuttle/Centaur flights is that they were for a long time planned to use 109% throttles on the main engines (for the heavy payload); I don't know where that stood at the time of the Challenger disaster, but I can imagine that John Young wasn't that confident in the results of the "full power level" ground testing at the time.  I think there were people worried the engines as much as the boosters at the time, perhaps more.
Title: Re: Challenger STS-51L
Post by: Spacely on 12/11/2005 06:27 PM
After reading that article, I'm fairly certain that if Challenger didn't happen, a Centaur-related disaster would have. Let's also not forget that in a universe where the Challenger doesn't explode, all EELV rocket lines would eventually be shut down, and all payloads put on shuttles. With more payloads on more shuttles, and more shuttle flights, it really would have been only a matter of time.

On the other hand...

If that inevitable shuttle disaster didn't end up happening until, say, 1996, instead of 1986, there's a decent chance that 10+ years of 15 shuttle flights a year may have had us a couple new military-only shuttles and a pretty cool Space Station Freedom.

Of course, in that scenario, I have a feeling solar system exploration budgets would have been sliced and diced and we would not have anywhere close to the current Mars program, Cassini, or the robust "Discovery" class missions. It's all so hard to predict!
Title: Re: Challenger STS-51L
Post by: Justin Space on 12/11/2005 06:40 PM
Quote
Spacely - 11/12/2005  7:27 PM

If that inevitable shuttle disaster didn't end up happening until, say, 1996, instead of 1986, there's a decent chance that 10+ years of 15 shuttle flights a year may have had us a couple new military-only shuttles and a pretty cool Space Station Freedom.

Of course, in that scenario, I have a feeling solar system exploration budgets would have been sliced and diced and we would not have anywhere close to the current Mars program, Cassini, or the robust "Discovery" class missions. It's all so hard to predict!

One thing we couldn't of stopped was the cooling of the Cold War.

Heaven's forbid, but if it all kicks off with China - and they go big on space, then I have a feeling that would open up a few options.
Title: Re: Challenger STS-51L
Post by: STS Tony on 12/11/2005 07:56 PM
Also prestige. It would be ironic if after beating the Red Machine of the Soviet Union to the Moon, we then lose to a weaker Russia to Mars.
Title: Re: Challenger STS-51L
Post by: Ben E on 12/11/2005 11:05 PM
Sticking with the Challenger and Vandenberg themes, is there any reason why some military flights HAD to be launched from California? I know they were mostly headed for polar orbits and needed to head south, but what difference would it have made if they'd headed for the poles down the east (KSC) or west (Vandenberg) seaboards?

Picking up on an earlier comment about the inevitability of another disaster, certainly there was a high risk on the 61F and 61G launches. If the Centaur missions had just been Ulysses and Galileo, the odds might have been okay, but I believe Magellan was originally pencilled-in for a Centaur launch in 1988 and so too were a few polar-orbiting and DoD satellites out of Vandenberg. Plus, of course, there was the inherently dangerous Vandenberg site itself, which had already turned up potential problems with its flame trench, soundwaves reflecting off the surrounding mountains and those dodgy-sounding filament-wound SRBs.

I shudder to admit it, but even without 51L, I think a disaster was not far off.
Title: Re: Challenger STS-51L
Post by: DaveS on 12/11/2005 11:22 PM
Quote
Ben E - 12/12/2005  1:05 AM
 but what difference would it have made if they'd headed for the poles down the east (KSC) or west (Vandenberg) seaboards?
Going south from KSC makes the flightpath cross inhabited land masses and if something goes wrong during ascent debris could fall on foreign soil and make the recovery and investigation much harder. Launching south  from Vandenberg avoids this as there's not much inhabited land masses in the flightpath. This why all polar orbit missions no matter if it is on the shuttle or on an conventional ELV launches from Vandenberg.
Title: Re: Challenger STS-51L
Post by: Super George on 12/12/2005 07:43 PM
Have I got this right be thinking a launch from KSC goes to the East, and the Vandenberg Shuttle missions would have gone to the West, as to the South is just rockets?
Title: Re: Challenger STS-51L
Post by: psloss on 12/12/2005 08:25 PM
Perhaps someone here knows of a better reproduction than this, but it's still useful:
http://stsliftoff.com/Documents/newsref/bigimages/launch_sites_8.jpg

(I believe that STS-36 went to 62 degrees inclination from KSC with a dogleg maneuver, I'm assuming after the trajectory cleared populated areas during second stage...)
Title: Re: Challenger STS-51L
Post by: Launch Fan on 12/12/2005 10:59 PM
And Discovery was going to have a new home in California? Reading the story about the Centuar launch, it seems to intimate this?
Title: Re: Challenger STS-51L
Post by: Super George on 12/12/2005 11:24 PM
Quote
psloss - 12/12/2005  3:25 PM

Perhaps someone here knows of a better reproduction than this, but it's still useful:
http://stsliftoff.com/Documents/newsref/bigimages/launch_sites_8.jpg

(I believe that STS-36 went to 62 degrees inclination from KSC with a dogleg maneuver, I'm assuming after the trajectory cleared populated areas during second stage...)

Thank you! Never seen any map like that before. Very cool :)
Title: Re: Challenger STS-51L
Post by: ADC9 on 12/13/2005 12:09 AM
Yes, very nice image. I wasn't actually aware they could launch Westerly?
Title: Re: Challenger STS-51L
Post by: psloss on 12/13/2005 12:53 AM
Quote
Launch Fan - 12/12/2005  6:59 PM

And Discovery was going to have a new home in California? Reading the story about the Centuar launch, it seems to intimate this?
Yes...well, eventually.  If I recall correctly, for the first few Vandenberg missions the Orbiter Maintenance and Checkout Facility (OMCF) at North Vandenberg wasn't ready to fully process the orbiter, so I believe after each of the first few missions Discovery was going to go back to KSC for post-flight servicing and whatever work needed to be done there and then ferried to the OMCF at Vandenberg to finish processing and transport to Slick Six for pad processing.

Philip Sloss
Title: Re: Challenger STS-51L
Post by: GregM on 12/13/2005 04:02 AM
If memory serves me correctly, Discovery was paid for by the DOD. One must remember at the time that this was the Reagan years. The military was riding very high, and had a seemingly limitless hi-tech future (and budget). The cold war was at it’s modern hi-tech peak, not to mention peak tensions. DOD had many of their people installed in key NASA positions , despite the fact that NASA was supposed to be a civilian agency. I believe in fact that the person running the shuttle program at the time was an active-duty Air Force General by the name of Jim Abramson. There were many in the DOD who were still bitter about repeated attempts to form a separate DOD manned spaceflight program in the 60’s ending in cancellation. Two “blue” DOD manned space programs, the Dyna-Soar and MOL were cancelled well into the program’s developments in the 60’s. A “Blue” astronaut corps had been selected and trained (I believe that Abramson was one of those astronauts), launch systems were being developed (based on Titan 3), spacecraft were being developed, launch facilities were being built (slick 6). The programs kept getting cancelled prior to a first flight however.

Now with the shuttle, the DOD was going to get between one quarter and one third of all shuttle flights eventually. The dream of some in the DOD to have a separate manned space program of their own was finally going to happen. To support this effort, there was again  going to be a separate DOD astronaut corps, a dedicated DOD shuttle orbiter, a dedicated DOD shuttle launch, landing, and orbiter processing facility, and a separate DOD mission control room at JSC in Houston. In essence, it was going to be a completely separate DOD  shuttle program operating independently within the existing NASA program. Most of the flights would be polar-orbit flights operating out of VAFB – flying black NSC stuff and SDI stuff (such as Teal Ruby), with occasional blue payloads requiring geosynchronous orbits still launching out of KSC. The DOD poured billions and billions into the “Blue Shuttle” program as it was called at the time. The program was so prestigious that the Secretary of the Air Force, Pete Alderich, was to fly as a crew member on the first or second Vandenburg blue shuttle flight. The Soviet development of Buran was a direct response to the Blue Shuttle program.

As for the Centaur upper stage, the only application that NASA really had for it was for launching the "flagship” interplanetary probes – of which there were very few (maybe 4 in 10 years). Most Centaur flights, had they gone on successfully, would have ultimately been on blue shuttle flights.

Of course with 51-L, it all fell apart. The anti-manned spaceflight faction within the DOD correctly saw the event as the opportunity to get the DOD out of the shuttle business, which it did. There were still serious technical and safety challenges at the VAFB shuttle complex (slick 6) that required rectification prior to a launch, and the Centaur program was always on less than a solid technical footing. The problems may have been eventually solved – but at yet greater cost than the huge outlay already spent by the federal government on the projects.

When the return to flight came in 1988, NASA flew the DOD payloads that were specifically designed for the shuttle out of KSC instead of Vandenburg as originally intended, with some compromises to the payloads designed for polar orbits. With that, the DOD’s expensive flirtation with manned spaceflight ended (at least as far as we know – there may well be black programs today that for all practical purposes are spaceflight programs).

If things had gone differently however, and there was no Challenger mishap, and the Blue Shuttle program got up and running successfully - we would have a VERY different space program today.
Title: Re: Challenger STS-51L
Post by: Rocket Guy on 12/13/2005 04:24 AM
Quote
psloss - 12/12/2005  4:25 PM

Perhaps someone here knows of a better reproduction than this, but it's still useful:
http://stsliftoff.com/Documents/newsref/bigimages/launch_sites_8.jpg

(I believe that STS-36 went to 62 degrees inclination from KSC with a dogleg maneuver, I'm assuming after the trajectory cleared populated areas during second stage...)

I don't know who made that map but it is totally inaccurate. 28 is more southerly than 39. 39 degress goes NE. Second, those SRB impact lines are WAY WAY too far out!
Title: Re: Challenger STS-51L
Post by: Rocket Guy on 12/13/2005 04:27 AM
Quote
ADC9 - 12/12/2005  8:09 PM

Yes, very nice image. I wasn't actually aware they could launch Westerly?

You can launch westerly, but in this case we are referring to sun-sync orbits which are more than 90 degrees (south southwest)...from 91 up to about 105 degrees.

While the Shuttle could not do it, they can launch westerly with the right rocket and small payload. It's all a matter of having enough fuel and thrust to push a payload into orbit with the Earth's rotational speed subtracted instead of added.

Edit: misspelled westerly 'weatherly'

Most polar orbits are retrograde by a few degrees, by the way.
Title: Re: Challenger STS-51L
Post by: Rocket Guy on 12/13/2005 04:28 AM
Quote
(at least as far as we know – there may well be black programs today that for all practical purposes are spaceflight programs).

I'm not sure what this implies :-) There are no secret military man in space programs.
Title: Re: Challenger STS-51L
Post by: psloss on 12/13/2005 01:56 PM
Quote
Ben - 13/12/2005  12:24 AM

I don't know who made that map but it is totally inaccurate. 28 is more southerly than 39. 39 degress goes NE. Second, those SRB impact lines are WAY WAY too far out!
You can get to 39 degrees inclination with different azimuths; so both northeast and southeast would work, though in practice I think 90 degrees is the maximum launch azimuth they'd use for a shuttle launch.  For the launches northeast to 39 degrees inclination, I think the azimuth would be in the 60 degree range...

Regarding the SRB impact lines, I agree, but I was looking for something to illustrate better than text such as:
http://spaceflight.nasa.gov/shuttle/reference/shutref/sts/launch.html

Philip Sloss
Title: Re: Challenger STS-51L
Post by: Rocket Guy on 12/13/2005 04:03 PM
They cannot launched to a 39 degree inc on a southeast azimuth because they will overly the Bahamas.

28 degrees is the 'southernmost' trajectory they launch into, and that launch azimuth is slightly south of east; not sure of the exact numbers. They can launch more than 90 degrees without overlying the Bahamas. Typical Delta 2 launch is about 104-105 degrees. 39 is slightly NE and anything above that is very NE.

On a couple of the DoD missions, by the way, they overflew the Outer Banks.
Title: Re: Challenger STS-51L
Post by: STS Tony on 12/14/2005 12:37 AM
Quote
Ben - 12/12/2005  11:28 PM

I'm not sure what this implies :-) There are no secret military man in space programs.

Damn Ben, I was hoping there was. Now I'm a bit down about the whole thing ;)
Title: Re: Challenger STS-51L
Post by: Rocket Guy on 12/14/2005 02:50 AM
Well there was that Shuttle launch the other day here from an underground silo, but trust me, it's not military.
Title: Re: Challenger STS-51L
Post by: UK Shuttle Clan on 12/28/2005 06:07 PM
One month to go until the 20th anniversary of this disaster. Can't believe it's been 20 years already.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 12/28/2005 10:11 PM
Yep, Jan 28, 1986. I'm looking to see if we can do a few articles based around the anniversary.
Title: Re: Challenger STS-51L
Post by: Super George on 12/28/2005 10:46 PM
I hope so, this has to be marked, not on some Apollo 1, Challenger and Columbia day, which is so wrong last year by NASA I can't even begin to say how much!
Title: Re: Challenger STS-51L
Post by: SimonShuttle on 12/30/2005 06:04 PM
Quote
Super George - 28/12/2005  5:46 PM

I hope so, this has to be marked, not on some Apollo 1, Challenger and Columbia day, which is so wrong last year by NASA I can't even begin to say how much!

I agree, but that was still a very respectful event.
Title: Re: Challenger STS-51L
Post by: James Lowe1 on 12/30/2005 10:02 PM
We're trying to prepare some articles for the anniversary.
Title: Re: Challenger STS-51L
Post by: Justin Space on 01/03/2006 04:21 PM
BBC are going to do something as well, a mate who works there just told me.
Title: Re: Challenger STS-51L
Post by: Jonesy STS on 01/06/2006 10:55 PM
Just been reading that post about the crew. That is awful, really shocking.
Title: Re: Challenger STS-51L
Post by: Hotol on 01/10/2006 02:05 PM
Having watched the Challenger Documentary on BBC2 this all makes sence. This was the first time a TV documentary noted they were likely to be alive and awake on the way down. This thread says more and confirms such a terrible situation for them. RIP.
Title: Re: Challenger STS-51L
Post by: Andy L on 01/12/2006 08:39 PM
20 years seems like a lot less. It does seem like less than that. I hope that doesn't take away the need for rememberance.
Title: Re: Challenger STS-51L
Post by: rsp1202 on 01/12/2006 08:53 PM
Well said.
And January 27 is 39th anniversary of Apollo One fire. Grissom, White, Chaffee.
Title: Re: Challenger STS-51L
Post by: psloss on 01/12/2006 11:23 PM
Quote
Hotol - 10/1/2006  10:05 AM

Having watched the Challenger Documentary on BBC2 this all makes sence. This was the first time a TV documentary noted they were likely to be alive and awake on the way down. This thread says more and confirms such a terrible situation for them. RIP.
NASA has been very reserved about this subject over the years (and I think justifiably so; the same is true with regard to the STS-107 crew); however, they did officially acknowledge that the 51-L crew survived the orbiter breakup that resulted from the explosion of the tank.  The wording is very conservative, but I think many people understood that some of the crew might have been conscious for a long time, and the press conference held to accompany this report by Joe Kerwin was covered on the evening newscasts that day (which happened to be six months to the day of the accident):
http://history.nasa.gov/kerwin.html
Title: Re: Challenger STS-51L
Post by: Orbiter Obvious on 01/13/2006 12:58 AM
Thanks for the link, pretty awful task having to do that investigation.
Title: Re: Challenger STS-51L
Post by: Martin FL on 01/13/2006 02:09 AM
Let's pray the decompression got them before anything else.
Title: Re: Challenger STS-51L
Post by: Avron on 01/13/2006 03:52 AM
The good news, is that we are going back to a LES
Title: Re: Challenger STS-51L
Post by: SimonShuttle on 01/30/2006 09:18 AM
Why did only one booster fail if it was too cold for the o-rings? Did the rings survive on the other SRB?
Title: Re: Challenger STS-51L
Post by: Hotol on 01/30/2006 12:55 PM
Quote
SimonShuttle - 30/1/2006  4:18 AM

Why did only one booster fail if it was too cold for the o-rings? Did the rings survive on the other SRB?

Not a bad question, but I think it was pure luck both didn't blow on the pad.
Title: Re: Challenger STS-51L
Post by: Dobbins on 01/30/2006 01:27 PM
A better question would be why didn't the other 5 joints fail. Each 4 segment SRB has 3 o-ring joints and only 1 of the 6 joints failed. In addition the one that failed did so at a point where the outgassing would strike the ET, a failure at a different point would have directed the flame away from the ET. There was an element of bad luck in addition to the bad design and practices.

Title: Re: Challenger STS-51L
Post by: Jackson on 03/20/2006 09:21 AM
Hi. New to this excellent site. This really moved me, so very sad to hear some of the things we didn't get to hear publically before. RIP.
Title: Re: Challenger STS-51L
Post by: Jamie Young on 03/20/2006 05:15 PM
Welcome to the site. Not a lot can be added to this thread. All very sad.
Title: Re: Challenger STS-51L
Post by: Jackson on 03/20/2006 08:49 PM
Quote
Jamie Young - 20/3/2006  12:15 PM

Welcome to the site. Not a lot can be added to this thread. All very sad.

I agree, but it's also something that needs to be known so as to add respect to the brave astronauts.
Title: Re: Challenger STS-51L
Post by: TheMadCap on 03/23/2006 12:02 AM
I was 14 years old and in Jr. High school at the time.

By that time, it was sort of rare to show shuttle flights on TV, but the Teacher in Space Program was all over the place. I remember being very much aware of the significance of sending a civilian into space.

I remember getting to Art class just after lunch that day, and everyone in class, a few teachers and students from other classes huddled around the television. I remember they just kept showing that replay over and over. Several people, including my Art teacher were openly weeping. I ended up leaving the room to try and make some sort of sense out of it. To go from total elation at seeing Columbia on STS-1 to this was a little more than I could bear. I cannot even begin to imagine the horror of the loved ones in attendance.

I also think it was a complete chance event that she didn't blow up on the pad. Roger Boisjoly has been quoted as saying he breathed a sigh of relief when Challenger got off the ground. I can't recall if they were able to recover any of the pieces from the other booster, I am sure someone here knows. For some reason, I want to say that the aft field joint was most affected by the o-ring problem; I remember hearing that the engineers at Thiokol seemed to focus on that particular section from earlier flights.

I recently saw a special on NGC that suggested a theory (?) about why the leak didn't cause an instant catastrophic event. Film evidence showed that a great deal of the o-ring on the aft field joint vaporized immediately upon ignition, hence the smoke seen right after liftoff. The program I watched implied that residue from the combustion of the solid fuel sealed the breach, allowing the flight to continue, seemingly as normal. But the stresses of Max Q degraded the "pseudo-seal" and allowed the gases to leak out, thus the flame seen in the launch video.

Did anyone see this program, it was called "Challenger: the Untold Story", I believe. Has anyone else heard this explanation for the SRB surviving to 73 seconds?
Title: Re: Challenger STS-51L
Post by: Jim on 03/23/2006 01:42 AM
That is the standard explanation for the breech lasting 73 seconds, but it was actually a wind shear it passed thru
Title: Re: Challenger STS-51L
Post by: Thomas ESA on 03/23/2006 10:18 AM
It was the strongest wind shere ever experienced by a Shuttle too. A terrible coincidence that would be suffered during a launch that simply didn't want it.
Title: Re: Challenger STS-51L
Post by: Hotol on 03/23/2006 12:54 PM
Quote
TheMadCap - 22/3/2006  7:02 PM


Did anyone see this program, it was called "Challenger: the Untold Story", I believe. Has anyone else heard this explanation for the SRB surviving to 73 seconds?

I think it was called something different on UK TV, but we saw that documentary and it was very well produced.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 03/23/2006 04:13 PM
Quote
Hotol - 23/3/2006  1:54 PM

Quote
TheMadCap - 22/3/2006  7:02 PM


Did anyone see this program, it was called "Challenger: the Untold Story", I believe. Has anyone else heard this explanation for the SRB surviving to 73 seconds?

I think it was called something different on UK TV, but we saw that documentary and it was very well produced.

It was this one:

http://forum.nasaspaceflight.com/forums/thread-view.asp?tid=1335&start=1
Title: Re: Challenger STS-51L
Post by: NASA_Twix_JSC on 03/25/2006 03:12 AM
Well the upturn in interest was understandable with the 20th anniversary. I hope it becomes a memorial to the crew, rather than a form of TV fascination with disaster. Thankfully these documentaries were respectfully produced.
Title: Re: Challenger STS-51L
Post by: zappafrank on 03/25/2006 03:23 AM
I'm reading Mike Mullane's book Riding Rockets, and he goes into some detail about Challenger that I've never really read before, its sad, and makes you pretty angry.

Mike flew with Judy Resnik on their first flight, and he later found out that one had some pretty serious SRB burn through as well, yet the astronauts were kept in the dark, and culture was autocratic with John Young heading up the Astronaut corp that no one would ever raise a concern or they thought they would be booted from the program.
Title: Re: Challenger STS-51L
Post by: zappafrank on 03/25/2006 03:33 AM
When Challenger was lost, I was at college, returned home, knowing there was a launch, and caught it as the camera was showing the explosion, but there was no explanation.

I remember thinking that the ship had to be intact and would do an abort landing, and I was looking for the craft.  Of course realizing, but not wanting to that the aerodynamics forced the breakup.


When Columbia was lost, I was in Mexico City, I had followed this mission closely, as I had worked with Rick Husband's brother, who is an airline pilot, and I had talked with him several times on the phone.  I missed when Rick visited our hangar, he met with lots of people and distributed lots of paraphenalia, and I thought his brother was a hell of a good guy.  So, I knew that it would be returning, and I got up early, but it was still an orbit or two to go, so I went to the Pyramids at Teotechuan and climbed them and all that.  I got back, and was walking in the Zocalo and they had newspapers out with the picture of the re-entry, I found that to be rather odd, and only glanced at it, not realizing what it meant.  I got back to the hotel and turned on CNN and watched in horror about what had happened.

I don't want this to happen again, I will sweat bullets for the remaining 18 or so missions.  I want a simple system to get men into space, lets spend the dough once we are up there and get the private market involved.
Title: Re: Challenger STS-51L
Post by: zappafrank on 03/25/2006 03:43 AM
As for the stories about the inflight recorder, I don't believe it, Mullane doesn't believe it.  He noted that they lost all electrical power on breakup, all the helmet mic's went dead, and all the astronauts kept their helmets on with the screen drawn (they do that to stay alive, using their emergency air packs (air, not oxygen).  Even with a recorder going somewhere (would have to be battery pack), you couldn't hear them through their helmets.

Yes, they were alive, they did survive, either Judy or El Onizuka turned on Scobee's air, and Mike Smith activated some of the switches (spring loaded, covered switches that could not have been activated due to the explosion).  Mike and Dick tried to gain control for an abort landing, but they had zero power and they most likely realized that pretty quickly.

Now, could a few of them survived had the ejection system that was on STS 1-4 been on Challenger?  Maybe, but its a good sight better than falling for two and half minutes and impacting the ocean.
Title: Re: Challenger STS-51L
Post by: Jim on 03/25/2006 05:13 AM
Quote
zappafrank - 24/3/2006  10:43 PM Now, could a few of them survived had the ejection system that was on STS 1-4 been on Challenger?  Maybe, but its a good sight better than falling for two and half minutes and impacting the ocean.

Doubt they could have activated them
Title: Re: Challenger STS-51L
Post by: UK Shuttle Clan on 03/25/2006 10:32 AM
I really want to think along those lines, but the guy posting the info on the post-breakup data is, with respect, in a better position to know than Mike Mullane. But it doesn't bare too much thinking about.
Title: Re: Challenger STS-51L
Post by: Ben E on 03/25/2006 07:13 PM
I think it just shows that, no matter how 'safe' the 'safety' upgrades may be, a fairly "inconsequential" quirk or effect or accident can have the most profound consequences. Who'd have thought Challenger would encounter that wind shear? Who'd have thought that piece of foam would hit Columbia's wing in the very place (RCC Panel 8/9 interface) where re-entry temperatures were the fiercest?

I've just been poring over an interview with Don Lind and he says that the STS-51B boosters suffered serious blow-by, too. Think STS-51C's ascent was even hairier, possibly seconds away from disaster, if you believe Roger Boisjoly.
Title: Re: Challenger STS-51L
Post by: Jamie Young on 03/25/2006 08:41 PM
Would Challenger have survived to SRB sep without the wind shear?
Title: Re: Challenger STS-51L
Post by: Ben E on 03/25/2006 09:27 PM
We'll never know.
Title: Re: Challenger STS-51L
Post by: TheMadCap on 03/26/2006 05:02 PM
Quote
Jamie Young - 25/3/2006  3:41 PM

Would Challenger have survived to SRB sep without the wind shear?


Truly, we will never know for sure. IMHO, I think she would have made it. But of course, that would have given both companies managements even more ammunition to dismiss the engineers’ fears. A disaster was inevitable; I think it was just a question of time...
Title: Re: Challenger STS-51L
Post by: zappafrank on 03/26/2006 10:23 PM
The second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.


Too many opportunities for something to go wrong.....
Title: Re: Challenger STS-51L
Post by: Hotol on 04/05/2006 02:38 PM
Quote
zappafrank - 26/3/2006  4:23 PM

The second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.


Too many opportunities for something to go wrong.....

Which launch was this and how was it evaluated before re-entry?
Title: Re: Challenger STS-51L
Post by: Jim on 04/05/2006 02:43 PM
Quote
Hotol - 5/4/2006  9:38 AM
Quote
zappafrank - 26/3/2006  4:23 PMThe second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.Too many opportunities for something to go wrong.....
Which launch was this and how was it evaluated before re-entry?

STS-27
Title: Re: Challenger STS-51L
Post by: psloss on 04/05/2006 02:47 PM
Quote
Hotol - 5/4/2006  10:38 AM

Quote
zappafrank - 26/3/2006  4:23 PM

The second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.


Too many opportunities for something to go wrong.....

Which launch was this and how was it evaluated before re-entry?
That was STS-27R, which was a DOD mission.  From info that came out after STS-107, they had an RMS on that flight and used it to assess some of the damage on-orbit.  (Presumably after the event was seen on the post-launch video/film review.)

I posted this here before, but here's a post-landing picture of the crew at Edwards...you can see some of the damage...
http://science.ksc.nasa.gov/mirrors/images/images/pao/STS27/10063088.jpg

Title: Re: Challenger STS-51L
Post by: psloss on 04/05/2006 02:49 PM
Another shot...weight on wheels...
http://science.ksc.nasa.gov/mirrors/images/images/pao/STS27/10063083.jpg

Title: Re: Challenger STS-51L
Post by: Ben E on 04/05/2006 02:58 PM
Was it just down to luck that STS-27 didn't suffer more serious problems during re-entry? I remember Mullane said later that "hundreds of tiles were gouged or scraped" - but were any actually lost?
Title: Re: Challenger STS-51L
Post by: psloss on 04/05/2006 03:32 PM
Quote
Ben E - 5/4/2006  10:58 AM

Was it just down to luck that STS-27 didn't suffer more serious problems during re-entry? I remember Mullane said later that "hundreds of tiles were gouged or scraped" - but were any actually lost?
Hazarding a guess, I would say they did have good luck that the shrapnel didn't hit something more critical.  And you probably can't see it in the photo, but I recall seeing on the post-flight video survey a large tile missing.  Reference:
http://members.aol.com/WSNTWOYOU/STS27MR.HTM

Quote
Initial postflight inspections of the exterior surface of the Orbiter revealed significant tile damage with 298 damage sites greater than 1 inch in area, and a total of 707 damage sites on the lower surface of the vehicle. The area of major damage was concentrated outboard of a line from the bi-pod attachment to the external tank (ET) liquid oxygen umbilical. One tile was missing on the right side slightly forward of the L-band antenna. Also, there were many damage sites consisting of long narrow streaks with deep gouges. The damage noted is the most severe of any mission yet flown.

I would infer from Astronautix (http://www.astronautix.com/flights/sts27.htm) that they think they were very lucky:
Quote
We have a problem: At T+85 seconds a large piece of debris struck the shuttle. The orbiter took 707 hits, 298 greater than an 2.4 cm in size. One tile was knocked off, but behind it was a thick plate covering the L-band antenna. Otherwise burn-through would have occurred.

Philip Sloss
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 08/28/2007 11:31 PM
Bumped for Jeff...this is the baseline thread. There are others - use the search function, remembering to select, titles, History Section and "all posts".

One example: http://forum.nasaspaceflight.com/search/query.asp?fid=0&action=search&searchforumid=25&keywords=Challenger&mode=1&subjects=1&author=&attachmentmode=0&attachmenttype=&days=1&datemode=3&custom-start=&custom-end=
Title: Re: Challenger STS-51L
Post by: jeff122670 on 08/29/2007 12:21 AM
thanks chris!!  i searched all over (even used the search function).....thanks for helping me out!!!!!!!!!!

Jeff
Title: Re: Challenger STS-51L
Post by: wingod on 08/29/2007 03:18 AM
Quote
Jim - 5/4/2006  9:43 AM

Quote
Hotol - 5/4/2006  9:38 AM
Quote
zappafrank - 26/3/2006  4:23 PMThe second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.Too many opportunities for something to go wrong.....
Which launch was this and how was it evaluated before re-entry?

STS-27

How can that be?  I thought 51L was the equivalent of STS-25 and that the RTF and the Discovery flight was STS 26?
Title: Re: Challenger STS-51L
Post by: Jorge on 08/29/2007 03:35 AM
Quote
wingod - 28/8/2007  10:18 PM

Quote
Jim - 5/4/2006  9:43 AM

Quote
Hotol - 5/4/2006  9:38 AM
Quote
zappafrank - 26/3/2006  4:23 PMThe second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.Too many opportunities for something to go wrong.....
Which launch was this and how was it evaluated before re-entry?

STS-27

How can that be?  I thought 51L was the equivalent of STS-25 and that the RTF and the Discovery flight was STS 26?

Umm... he did say second launch after Challenger...

http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/list_main.html
Title: Re: Challenger STS-51L
Post by: Jorge on 08/29/2007 03:41 AM
Quote
psloss - 5/4/2006  9:47 AM

Quote
Hotol - 5/4/2006  10:38 AM

Quote
zappafrank - 26/3/2006  4:23 PM

The second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.


Too many opportunities for something to go wrong.....

Which launch was this and how was it evaluated before re-entry?
That was STS-27R, which was a DOD mission.  From info that came out after STS-107, they had an RMS on that flight and used it to assess some of the damage on-orbit.  (Presumably after the event was seen on the post-launch video/film review.)

That's correct. The relevant details are in CAIB vol. 1, p. 127.

Quote
When Atlantis was launched on STS-27R on December 2, 1988, the largest debris event up to that time significantly damaged the Orbiter. Post-launch analysis of tracking camera imagery by the Intercenter Photo Working Group identified a large piece of debris that struck the Thermal Protection System tile at approximately 85 seconds into the flight. On Flight Day Two, Mission Control asked the flight crew to inspect Atlantis with a camera mounted on the remote manipulator arm, a robotic device that was not installed on Columbia for STS-107. Mission Commander R.L. “Hoot” Gibson later stated that Atlantis “looked like it had been blasted by a shotgun.”18 Concerned that the Orbiter's Thermal Protection System had been breached, Gibson ordered that the video be transferred to Mission Control so that NASA engineers could evaluate the damage.

When Atlantis landed, engineers were surprised by the extent of the damage. Post-mission inspections deemed it “the most severe of any mission yet flown.”19 The Orbiter had 707 dings, 298 of which were greater than an inch in one dimension. Damage was concentrated outboard of a line right of the bipod attachment to the liquid oxygen umbilical line. Even more worrisome, the debris had knocked off a tile, exposing the Orbiter's skin to the heat of re-entry. Post-flight analysis concluded that structural damage was confined to the exposed cavity left by the missing tile, which happened to be at the location of a thick aluminum plate covering an L-band navigation antenna. Were it not for the thick aluminum plate, Gibson stated during a presentation to the Board that a burn-through may have occurred.
Title: Re: Challenger STS-51L
Post by: wingod on 08/29/2007 03:42 AM
Quote
Jorge - 28/8/2007  10:35 PM

Quote
wingod - 28/8/2007  10:18 PM

Quote
Jim - 5/4/2006  9:43 AM

Quote
Hotol - 5/4/2006  9:38 AM
Quote
zappafrank - 26/3/2006  4:23 PMThe second launch after the Challenger had a piece of the SRB nose cone hit the bottom of the orbiter and rip up a hell of a lot of tiles.Too many opportunities for something to go wrong.....
Which launch was this and how was it evaluated before re-entry?

STS-27

How can that be?  I thought 51L was the equivalent of STS-25 and that the RTF and the Discovery flight was STS 26?

Umm... he did say second launch after Challenger...

http://www.nasa.gov/mission_pages/shuttle/shuttlemissions/list_main.html

Ur right, brain fart on my part, I read it as second flight of Challenger for some darn reason.

Title: Re: Challenger STS-51L
Post by: chksix on 08/29/2007 10:07 PM
I was 19 at the time. I woke up in the morning to prepare for school and heard the horrible and unbelievable news on the radio. The STS program has been a fascination of mine ever since the first concept drawings of the new system were revealed in the press and books about spaceflight. Once STS-1 lifted off I started collecting all newsclips from the daily newspapers of all flights into a binder. I think I still have it at my parents house. Sadly that clipbook ends with Challenger.
Title: Re: Challenger STS-51L
Post by: APG85 on 08/30/2007 12:14 AM
The Challenger accident from a slightly different angle (hopefully not posted previously).  Always sad...

http://www.youtube.com/watch?v=YAzA6k-spnc
Title: Re: Challenger STS-51L
Post by: dwmzmm on 08/30/2007 02:58 AM
I was a restaurant manager at the time, working long hours almost every day (also, due to this, I had basically dropped out of my favorite hobby, model rocketry, beginning in late 1982 - 2003 because I was just too busy working), but I got a call from my mother,
who taught at a school nearby, to tell me Challenger "crashed."  I had to wait until I got off after close (like 11:30 PM) before I could
race home and watch the story/replays on CNN.  But the first feeling I got upon my mom's call was sheer horror, like someone just
blasted my stomach with a sledge hammer.  A few hours later, my brother-in-law called to give me a detailed, play by play account
of what they were showing on TV.  

Having had circumstances change, and being able to get back into model rocketry in later 2003, I'm proud that I was able to join the
Challenger 498 model rocket club based in far west Houston, and serve as NAR Section Advisor.  The club was formed and named in
honor of the Challenger Shuttle & crew in 1988, and I've organized (and will serve as contest director) our first NAR Sanctioned contest,
the Challenger Memorial Regional Meet, next March here in Katy, TX.
Title: Re: Challenger STS-51L
Post by: luke strawwalker on 09/05/2007 05:52 PM
I remember that day like it was yesterday... I had missed school that day to get the cotton fields hipped up (soil worked up) for planting in a few weeks.   I was born and raised on a cotton farm and that was my passion-- farm work.  My Grandad had passed away nearly two years to the day before and so I had to fill his shoes, and back then they weren't NEARLY as strict on missing school as they are now...  I missed a lot.  I still remember driving the tractor that day, quite cool, nice north breeze, but with warm sunshine, just a beautiful clear cool late winter/early spring day near Houston.  I knew the shuttle was going up and hoped to catch some of the news around lunchtime.   I was working about 100 yards out in the field in front of my parent's house when my Dad pulled up in the pickup.  He told me, "the space shuttle just blew up" and I didn't believe it.  I said 'nah, couldn't be' and he said "get in I'll take you to the house (Grandma's house) for lunch".   As we rode down there I kept thinking to myself, 'nah, he must've misunderstood.  He must've seen the SRB's jettison and since they throw that big cloud of smoke out he must've thought it blew up."  My Dad wasn't particularly interested in the space shuttle or anything of that sort but I sure was; it was my favorite thing to watch, read about, and dream about.  It was about a month or so before my 15th birthday, and I was a freshman in high school.  Well, when we went in the house Grandma had the TV on and they were showing the fireball cloud and debris hitting the water, and before long they showed a replay of the launch itself.  I couldn't believe it.  It was just SO sad.  I couldn't help thinking later on that SOMEBODY had screwed up royally.   But at the time I was just pretty numb and didn't know what to think... I popped a tape in the VCR and left it recording the rest of the day, but I could only watch it once... I think it's still in the closet.  

I remember the funeral service and President Reagan speaking, the footage of the families and especially the children of the astronauts.  I remember President Reagan quoting the poem "they have slipped the surly bonds of earth, to touch the face of God" and how moving that was... I had heard that poem before in a documentary about the space program, about Apollo 11 if I remember right, read by Orson Welles I think.

It's burned in my mind too, because my 8th grade history teacher was an old friend of my Dad from Shiner, TX (home of Shiner beer).  They had played football together in high school.  Mr. Reichardt was a GREAT guy, just the nicest guy you'd ever want to meet, and a great teacher, just a big ol' bear of a guy.  I remember reading about the 'teacher in space' thing and suggesting to him that he aught to sign up for that.  He just smiled and said, "Nah, don't think so."  The thought that someone I knew could have been in there was just eerie.  

For Columbia I had just got home from Indiana and taking the wife to see the inlaws.  I had goofed on my mother in law's computer quite a bit while I was up there, since there isn't much else for me to do (since I'm not interested in sewing and geneaology) and I had been showing the neice/nephews some of the NASA sites and stuff on the internet about the space program and stuff, trying to spark a little interest, watching the tracking programs that show where the shuttle and ISS were in orbit in realtime and stuff like that, the 3D tracking program, etc.  We also watched a bit on the news about the mission and saw some of the stuff on the NASA website and I explained things to the kids...

I was just getting up that morning and flipped on the TV news, and they came in with breaking news about the shuttle and nobody really knew what was going on, but when they showed the early pictures from the Dallas affiliates and stuff I just knew.  Half a dozen shooting stars across the sky over north and east Texas.  They cut to the weatherman and he was showing recordings of the weather radar showing the debris path across northeast Texas.   About this time the home videos started showing up on the TV and reports from the 911 calls all across East Texas and then shortly thereafter video from the ground from citizens and the local police/sheriff's and first responders, debris raining down in the streets of Jasper and Hemphill and Palestine TX.  Palestine had TONS of debris all over town.  They showed a house and interviewed a man who had found partial remains of a crew person in his front yard and draped an american flag over them until the authorities could come.  God that hit me like a hammer... still does.   That and the picture of the partially burned helmet someone else found in their front yard, and the mission patch that fluttered down on a roadside.  I thought about Elan Ramon, the first Israeli astronaut and how he died over Palestine, TX, and the sad irony of that.   It was the first shuttle mission I had followed somewhat closely since the original HST servicing mission with Story Musgrave.  I kinda fell into that 'been there done that so what' mentality myself.   It was just a million wonders nobody on the ground got killed by shuttle debris.   I understand that now they have altered the re-entry paths to avoid flying over inhabited areas.   At the time, those of us watching the local news really knew more about what was happenening than mission control did... all they had was 'loss of signal' and the PAO couldn't tell them anything more than that.   Reporters showed NASA workers at JSC running to TV sets to see the video from East Texas and Dallas and pretty quickly deduced that Columbia was gone, but nothing was said until it was past the landing time and it was quite obvious she hadn't landed in Florida and had to be down SOMEWHERE.   Then the pictures of the families and dignitaries waiting at the runway in Florida... broke my heart...

OL JR
Title: Re: Challenger STS-51L
Post by: Peter NASA on 09/05/2007 11:45 PM
Quote
APG85 - 29/8/2007  7:14 PM

The Challenger accident from a slightly different angle (hopefully not posted previously).  Always sad...

http://www.youtube.com/watch?v=YAzA6k-spnc

Doesn't play.
Title: Re: Challenger STS-51L
Post by: ChrisGebhardt on 09/06/2007 12:34 AM
Quote
Peter NASA - 5/9/2007  7:45 PM

Quote
APG85 - 29/8/2007  7:14 PM

The Challenger accident from a slightly different angle (hopefully not posted previously).  Always sad...

http://www.youtube.com/watch?v=YAzA6k-spnc

Doesn't play.

Played fine for me
Title: Re: Challenger STS-51L
Post by: STS Tony on 09/06/2007 10:29 PM
Worked for me too
Title: Re: Challenger STS-51L
Post by: emarkay on 09/08/2007 02:52 PM
Does anyone else have a copy of the "official" video (that has been shown countless times; containing the close up zoom image up to the point where the breakup of the ET begins, then the quick camera switch to the pullback zoom as the vapor cloud forms and the SRB's begin to veer away) that has the few extra frames of the first section, that show the nose section separating, pointing towards the ET, as  nose RCS thrusters fire or ignite?  It was broadcast only on the first day, and apparently only once or twice.  I still have a copy of it, recorded from CBS news that afternoon, on Beta, and have never heard any other comments on this.

My copy is starting to deteriorate, but I did take a "frame by frame" from my television a few years ago, and made an animation of it. I just wanted to see if there was anyone else who knows of this, in case the tape degrades beyond use.

MRK
Title: Re: Challenger STS-51L
Post by: APG85 on 09/10/2007 05:38 PM
Quote
emarkay - 8/9/2007  10:52 AM

Does anyone else have a copy of the "official" video (that has been shown countless times; containing the close up zoom image up to the point where the breakup of the ET begins, then the quick camera switch to the pullback zoom as the vapor cloud forms and the SRB's begin to veer away) that has the few extra frames of the first section, that show the nose section separating, pointing towards the ET, as  nose RCS thrusters fire or ignite?  It was broadcast only on the first day, and apparently only once or twice.  I still have a copy of it, recorded from CBS news that afternoon, on Beta, and have never heard any other comments on this.

My copy is starting to deteriorate, but I did take a "frame by frame" from my television a few years ago, and made an animation of it. I just wanted to see if there was anyone else who knows of this, in case the tape degrades beyond use.

MRK

Is this what you're talking about?

http://www.youtube.com/watch?v=BxeV3GadEcw
Title: Re: Challenger STS-51L
Post by: AstroRJY on 09/10/2007 06:17 PM
Interesting how fuzzy some of those 1980's long-range tracking images are before the clarity of the later flights in the 90's and afterwards.
Title: Re: Challenger STS-51L
Post by: nathan.moeller on 09/10/2007 07:19 PM
Quote
AstroRJY - 10/9/2007  1:17 PM

Interesting how fuzzy some of those 1980's long-range tracking images are before the clarity of the later flights in the 90's and afterwards.

The STS-51J launch was covered with the same camera and it was almost crystal clear.  Not sure what happened in this case.
Title: Re: Challenger STS-51L
Post by: AstroRJY on 09/10/2007 07:47 PM
Quote
nathan.moeller - 10/9/2007  3:19 PM

Quote
AstroRJY - 10/9/2007  1:17 PM

Interesting how fuzzy some of those 1980's long-range tracking images are before the clarity of the later flights in the 90's and afterwards.

The STS-51J launch was covered with the same camera and it was almost crystal clear.  Not sure what happened in this case.

I've seen the 51-J launch and a  few others from that era of the same shot you're thinking of.. what you're thinking of are the DOAMS trackers...this is a different one farther away, more remote, an engineering tracker.

Go to the  Video section Resource Index and scroll down  to the links to the Challenger websites and they have a few other long range cameras of it on there.
Title: Re: Challenger STS-51L
Post by: APG85 on 09/10/2007 08:22 PM
Whats the best book on the Challenger disaster?  Thanks.
Title: Re: Challenger STS-51L
Post by: Naraht on 09/10/2007 08:28 PM
Quote
APG85 - 10/9/2007  9:22 PM
Whats the best book on the Challenger disaster?  Thanks.

Depends what you're looking for. "No Downlink" by Claus Jensen is a good, broadly-focused account for general readers. If you want a more detailed account of the technical and organizational causes of the accident, though, look no further than "The Challenger Launch Decision: Risky Technology, Culture and Deviance at NASA" by Diane Vaughan. It is very densely written, but a brilliant analysis and one which I think would be very difficult to surpass.
Title: Re: Challenger STS-51L
Post by: AstroRJY on 09/10/2007 08:32 PM
I also would put in a good word for "Challenger: The Final Voyage"  by Richard S. Lewis, most likely in your local public library.
Title: Re: Challenger STS-51L
Post by: emarkay on 09/11/2007 01:05 AM
Oh the famous "Out of Focus" Cameras.  I remember AW&ST stills from those.  They also had a video of those out for a while.  But while it does shoe the event inquestion, I haev and saw a video feed, not a film feed.
Title: Re: Challenger STS-51L
Post by: Real Madrid on 09/29/2007 02:44 PM
I have a question : had the crew parachutes during launching or in the shuttle ?
and I have another question: had some crew members were nevertheless still in life after explosion?
Title: Re: Challenger STS-51L
Post by: Jim on 09/29/2007 02:51 PM
No parachutes before 51-L.  Read the accident report about the crew
Title: Re: Challenger STS-51L
Post by: Real Madrid on 10/06/2007 05:52 PM
I have Read that 15 launches were planned before the accident with the challenger  in 1986 thus 1986 was the year of  the space shuttle?
with 2  lunches from  Launch Complex 6  at  Vandenberg Airforce base this missions were STS-1V/62A and STS-82-M. and I know what STS-51-L mean.

5 - the 5th year of the Space Shuttle program, the first year of which was 1981. In the case of STS-51L, the mission was targeted for 1985, the fifth calendar year of the Space Shuttle program,
1 for KSC
L For the 12th Space Shuttle mission manifested by NASA for flight in 1985.

some information founded on http://www.spaceline.org/challenger/challist.html
Title: Re: Challenger STS-51L
Post by: Jim on 10/06/2007 06:03 PM
incorrect and so is the website

5 - the last digit of fiscal year 1985, In the case of STS-51L, the mission was targeted for fiscal 1985,
1 for KSC
L For the 12th Space Shuttle mission manifested by NASA for flight in fiscal year 1985.

The second launch from VAFB was 62-B not STS-82-M.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 10/06/2007 06:15 PM
Quote
Real Madrid - 29/9/2007  3:44 PM

I have a question : had the crew parachutes during launching or in the shuttle ?
and I have another question: had some crew members were nevertheless still in life after explosion?

Take time to read through the thread, as it's all answered.
Title: Re: Challenger STS-51L
Post by: toddbronco2 on 01/22/2010 01:04 AM
Are there still large amounts of Challenger that were never recovered from the ocean, or did they manage to recover a lot.  I don't think that I've ever seen a picture of the Challenger wreckage lain out the way they did with Columbia, so I suppose they didn't bother with that.  Does anybody have a reference showing images of the recovered wreckage?
Title: Re: Challenger STS-51L
Post by: Jorge on 01/22/2010 01:15 AM
Are there still large amounts of Challenger that were never recovered from the ocean, or did they manage to recover a lot.  I don't think that I've ever seen a picture of the Challenger wreckage lain out the way they did with Columbia, so I suppose they didn't bother with that.  Does anybody have a reference showing images of the recovered wreckage?

The recovery concentrated mainly on the SRBs (for accident investigation) and the crew cabin (for return of the crew remains). Most of the rest of the orbiter, and most of the ET, was never recovered.
Title: Re: Challenger STS-51L
Post by: JonSBerndt on 01/22/2010 01:19 AM
Are there still large amounts of Challenger that were never recovered from the ocean, or did they manage to recover a lot.  I don't think that I've ever seen a picture of the Challenger wreckage lain out the way they did with Columbia, so I suppose they didn't bother with that.  Does anybody have a reference showing images of the recovered wreckage?

There are some images of recovered hardware (mostly of SRB debris, as I recall) interspersed within the Rogers Report: http://history.nasa.gov/rogersrep/genindex.htm.

Title: Re: Challenger STS-51L
Post by: toddbronco2 on 01/22/2010 01:20 AM
Are there still large amounts of Challenger that were never recovered from the ocean, or did they manage to recover a lot.  I don't think that I've ever seen a picture of the Challenger wreckage lain out the way they did with Columbia, so I suppose they didn't bother with that.  Does anybody have a reference showing images of the recovered wreckage?

The recovery concentrated mainly on the SRBs (for accident investigation) and the crew cabin (for return of the crew remains). Most of the rest of the orbiter, and most of the ET, was never recovered.

I guess that surprises me after seeing how every tiny scrap of Columbia was carefully bagged and documented.  Yes, I understand that there might not have been much to learn from the wreckage of the orbiter, but still...the watery grave just seems odd and maybe a bit callous to me. 

I guess my original question still remains though, has anybody ever seen images of the recovered pieces of Challenger, the SRB's, or the ET?
Title: Re: Challenger STS-51L
Post by: JonSBerndt on 01/22/2010 01:26 AM
I guess my original question still remains though, has anybody ever seen images of the recovered pieces of Challenger, the SRB's, or the ET?

Our posts crossed paths. See above.
Title: Re: Challenger STS-51L
Post by: comethunter on 01/24/2010 07:06 PM
I became a big fan of shuttle after watching the first launch with amazement and started video taping every launch from STS-3 on (having since transfered to DVD).  I recently watched my CNN coverage of that morning and the launch itself and at the time, I certainly didn't think they would go (and wondering why I had skipped college classes).  I think even Tom Mintier was convinced they wouldn't.  But they did and I knew instantly literally exclaiming, "Oh ****, the **** thing blew up!"  It's tough to reflect on the accident(s) but its very important not to forget.  Hard to believe Challenger is soon to be 24 years.  Peace be with the crew and families.
Title: Re: Challenger STS-51L
Post by: Ray125 on 01/28/2010 09:38 PM
Today is January 28, 2010, it has been 24 years since the Challenger disaster. We will never forget them, nor the last time we saw them, in that morning, as the crew prepared for their journey and waved goodbye and slipped the surly bonds of Earth to touch the face of God. R.I.P.
Title: Re: Challenger STS-51L
Post by: SpaceUSMC on 01/30/2010 02:00 AM
I was kind of sad that nobody in the media seemed to mention the fact yesterday. In fact NASA TV was the only place I saw anything on it.
Title: Re: Challenger STS-51L
Post by: Jorge on 01/30/2010 02:38 AM


My first reaction was shock. Then white hot anger because I was sure the launch had been pushed under unfavorable conditions so President Reagan could brag about the Teacher in Space during his State of the Union address that was scheduled for that night.



Several investigations of this theory - including by democrat politicians and their media allies since the accident - have found absolutely NO evidence whatsoever that the launch was pushed "so President Reagan could brag about the Teacher in Space during his State of the Union address that was scheduled for that night." It's time to give it a rest already and place this theory where it belongs once and for all - with the equally laughable Apollo hoax theories.

That's a very old post you're responding to, but yes, you're right. There is no evidence to support this allegation (I refuse to dignify it with the name "theory").
Title: Re: Challenger STS-51L
Post by: brad2007a on 01/30/2010 02:42 AM


My first reaction was shock. Then white hot anger because I was sure the launch had been pushed under unfavorable conditions so President Reagan could brag about the Teacher in Space during his State of the Union address that was scheduled for that night.



Several investigations of this theory - including by democrat politicians and their media allies since the accident - have found absolutely NO evidence whatsoever that the launch was pushed "so President Reagan could brag about the Teacher in Space during his State of the Union address that was scheduled for that night." It's time to give it a rest already and place this theory where it belongs once and for all - with the equally laughable Apollo hoax theories.

That's a very old post you're responding to, but yes, you're right. There is no evidence to support this allegation (I refuse to dignify it with the name "theory").

I just removed my post after realizing how old the one I was responding to was (should have checked the date on it... :-[)

Anyway, thanks for the backup. Of course you are right.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 01/30/2010 03:28 AM
It's a good point. I was thinking of doing something on the 28th, but it gets to the point where you can overdo something, and how many times do you want to go over this unless you have something drastically new to report? You risk disrespect, and we're shuttle specific, everyone here knows the two dates, you don't need an article from us to remind you.

It's also very close to another shuttle mission, and that does make you think twice as there's an unhealthy amount of death watch media who start to take an interest in shuttle close to a launch.

It's a tough one, but myself and Chris G will have a think.
Title: Re: Challenger STS-51L
Post by: SpaceUSMC on 01/30/2010 04:02 AM
I can see where your coming from on this.
Title: Re: Challenger STS-51L
Post by: Danderman on 02/04/2010 10:01 PM
http://www.youtube.com/watch?v=41jq_5ltkno&feature=player_embedded
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 02/04/2010 10:33 PM
Not a lot you can say to that, is there.
Title: Re: Challenger STS-51L
Post by: Ronsmytheiii on 02/02/2011 12:12 AM
Sorry to bump an old topic, but here is an FBI report on the flight:

http://foia.fbi.gov/filelink.html?file=/shuttle/shuttle1a.pdf
http://foia.fbi.gov/filelink.html?file=/shuttle/shuttle1b.pdf
http://foia.fbi.gov/filelink.html?file=/shuttle/shuttle1c.pdf
Title: Re: Challenger STS-51L
Post by: Spooks on 02/02/2011 02:19 AM
I think we remember what we do from that day, and that's just the way it was meant for it to be.

I have what I saw and felt, and those around did as well, that's all I need or could every want...

Same as I stood alone in North Texas on February 3, 2003.

God's speed. 
Title: Re: Challenger STS-51L
Post by: Mark Dave on 08/15/2011 10:03 PM
Are there any pre launch photos of the Challenger  stack on this flight? Google isn't any help as mostly I find the explosion cloud or just the launch photos.

There is also this NASA  video of the  accident.


http://www.youtube.com/watch?v=lQMuRbCaZ7E
Title: Re: Challenger STS-51L
Post by: dvsmith on 08/16/2011 05:07 PM
Why did only one booster fail if it was too cold for the o-rings? Did the rings survive on the other SRB?

I remember reading somewhere (it may have been Randy Avera's largely execrable book) that the refurbished SRB casings were significantly out-of-round, such that any given segments would not necessarily line-up without mechanical coercion. That, in the author's opinion is what led to the failure of the SRB field joint on 51-L and prior flights.

(Yes, I realize how long ago the original comment was posted.)
Title: Re: Challenger STS-51L
Post by: kevin-rf on 08/16/2011 07:33 PM
Why did only one booster fail if it was too cold for the o-rings? Did the rings survive on the other SRB?

I remember reading somewhere (it may have been Randy Avera's largely execrable book) that the refurbished SRB casings were significantly out-of-round, such that any given segments would not necessarily line-up without mechanical coercion. That, in the author's opinion is what led to the failure of the SRB field joint on 51-L and prior flights.

(Yes, I realize how long ago the original comment was posted.)

I vaguely recall from somewhere, wind direction was part of it. The wind was such that one of the SRB's was down wind and further chilled by the ET than the other SRB.
Title: Re: Challenger STS-51L
Post by: TFGQ on 08/16/2011 08:10 PM
guys

i think we should let all that is unknown be about what happened in respect for the familes and the crew and people that were in the launch control center and mission control that day or where watching it just my thoughts  it's enough i am having nightmares and flash backs about everthing that happened in the program and the near misses

Just my opinion
Title: Re: Challenger STS-51L
Post by: Galactic Penguin SST on 01/28/2013 03:50 PM
In memoriam: Scobee/Smith/Resnik/McNair/Onizuka/Jarvis/McAuliffe/OV-099

I was not born until 7 years after that cold January morning, but it has always been my first taste of the pioneers who sacrificed their lives in the exploration and development of the final frontier. Even before another seven astronauts and one orbiter was lost again.

Hail Challenger
Title: Re: Challenger STS-51L
Post by: rdale on 01/21/2014 02:31 PM
Newly discovered pictures - http://imgur.com/a/6t1HW
Title: Re: Challenger STS-51L
Post by: Mr. Justice on 01/25/2014 02:22 AM
I hope that someone is able to help me with this. I was recently looking at pictures of the Challenger accident. I have never notice it before but there appears to be sort of flame near one main engine or, perhaps, coming from the area near the rcs.

http://www.npr.org/templates/story/story.php?storyId=5175151
Title: Re: Challenger STS-51L
Post by: edkyle99 on 01/25/2014 04:19 AM
I hope that someone is able to help me with this. I was recently looking at pictures of the Challenger accident. I have never notice it before but there appears to be sort of flame near one main engine or, perhaps, coming from the area near the rcs.

http://www.npr.org/templates/story/story.php?storyId=5175151
It might be similar to what is described in the paragraph from the following link.
http://history.nasa.gov/rogersrep/v1ch3.htm
"At 45 seconds into the flight, three bright flashes appeared downstream of the Challenger's right wing. Each flash lasted less than one-thirtieth of' a second. Similar flashes have been seen on other flights. Another appearance of a separate bright spot was diagnosed by film analysis to be a reflection of main engine exhaust on the Orbital Maneuvering System pods located at the upper rear section of the Orbiter. The flashes were unrelated to the later appearance of the flame plume from the right Solid Rocket Booster."

It looks more like a reflection of SRB exhaust in the following photos.
http://history.nasa.gov/rogersrep/v1p26.htm
Keep in mind that some images were "enhanced" by the Rogers Commission investigation team to highlight the SRB leak, which would brighten the reflection.

 - Ed Kyle
Title: Re: Challenger STS-51L
Post by: Mr. Justice on 01/25/2014 03:38 PM
I hope that someone is able to help me with this. I was recently looking at pictures of the Challenger accident. I have never notice it before but there appears to be sort of flame near one main engine or, perhaps, coming from the area near the rcs.

http://www.npr.org/templates/story/story.php?storyId=5175151
It might be similar to what is described in the paragraph from the following link.
http://history.nasa.gov/rogersrep/v1ch3.htm
"At 45 seconds into the flight, three bright flashes appeared downstream of the Challenger's right wing. Each flash lasted less than one-thirtieth of' a second. Similar flashes have been seen on other flights. Another appearance of a separate bright spot was diagnosed by film analysis to be a reflection of main engine exhaust on the Orbital Maneuvering System pods located at the upper rear section of the Orbiter. The flashes were unrelated to the later appearance of the flame plume from the right Solid Rocket Booster."

It looks more like a reflection of SRB exhaust in the following photos.
http://history.nasa.gov/rogersrep/v1p26.htm
Keep in mind that some images were "enhanced" by the Rogers Commission investigation team to highlight the SRB leak, which would brighten the reflection.

 - Ed Kyle

Thanks, I appreciate it.
Title: Re: Challenger STS-51L
Post by: spacecane on 01/26/2014 03:44 AM
I have read the explanation from NASA that the crackle sound heard was the radios trying to find a frequency.  If this was true, why does the sound happen before the breakup of the orbiter?  To me it seems the sound starts as soon as the bottom of the LH2 tank fails and then gets louder when the flash is seen between the ET and the orbiter.

Also, is the recording of the mission control ground loops available anywhere?
Title: Re: Challenger STS-51L
Post by: Jim on 01/26/2014 10:43 AM

Also, is the recording of the mission control ground loops available anywhere?

no
Title: Re: Challenger STS-51L
Post by: Jim on 01/26/2014 10:45 AM
  To me it seems the sound starts as soon as the bottom of the LH2 tank fails and then gets louder when the flash is seen between the ET and the orbiter.

Because interference from all the gases
Title: Re: Challenger STS-51L
Post by: brad2007a on 01/26/2014 06:21 PM

Also, is the recording of the mission control ground loops available anywhere?

no

Actually, if by "mission control ground loops" he means either the Flight Director's loop, or the PAO loop, they are available on YouTube (just search under "Challenger"). If he actually meant to say the "orbiter voice recordings", then the answer is no, of course.
Title: Re: Challenger STS-51L
Post by: spacecane on 01/26/2014 08:09 PM

Also, is the recording of the mission control ground loops available anywhere?

no

Actually, if by "mission control ground loops" he means either the Flight Director's loop, or the PAO loop, they are available on YouTube (just search under "Challenger"). If he actually meant to say the "orbiter voice recordings", then the answer is no, of course.

I meant the Flight Director's loop or similar from mission control.  I was just curious to hear how the controllers handled the recognition of the event.  I'd never want to hear the orbiter voice recordings.  The only thing I've ever been curious about is to know what video frame matches the "uh-oh" in the transcript.
Title: Re: Challenger STS-51L
Post by: brad2007a on 01/27/2014 08:48 PM

Also, is the recording of the mission control ground loops available anywhere?

no

Actually, if by "mission control ground loops" he means either the Flight Director's loop, or the PAO loop, they are available on YouTube (just search under "Challenger"). If he actually meant to say the "orbiter voice recordings", then the answer is no, of course.

I meant the Flight Director's loop or similar from mission control.  I was just curious to hear how the controllers handled the recognition of the event.  I'd never want to hear the orbiter voice recordings.  The only thing I've ever been curious about is to know what video frame matches the "uh-oh" in the transcript.

Oh. Then yes, they are available to be heard - check on YouTube or, if you can get a hold of a copy, the Spacecraft Films "Challenger" DVD set.
Title: Re: Challenger STS-51L
Post by: spacecane on 01/29/2014 01:18 PM
To start this question, I don't believe that the RCS was used during ascent.  My question is theoretical.

IF a scenario such as what happened was envisioned as a possibility, could the RCS have been used to keep the orbiter pointing into the slipstream during the stack breakup (assuming an out of control SRB didn't crash into it)?  Could doing this have allowed the orbiter to stay intact and allowed the crew to perform a controlled ditching and had a chance to survive?
Title: Re: Challenger STS-51L
Post by: Jim on 01/29/2014 01:27 PM

IF a scenario such as what happened was envisioned as a possibility, could the RCS have been used to keep the orbiter pointing into the slipstream during the stack breakup (assuming an out of control SRB didn't crash into it)?  Could doing this have allowed the orbiter to stay intact and allowed the crew to perform a controlled ditching and had a chance to survive?

No, forces were too great.
Title: Re: Challenger STS-51L
Post by: edkyle99 on 01/29/2014 03:13 PM
Re: the crew recordings.  For our younger readers, who might run across some fantastic, false claims on the World Wide Web, a bit of authoritative background is available here:
http://www.nytimes.com/1986/07/29/science/challenger-crew-knew-of-problem-data-now-suggest.html
and here:
http://history.nasa.gov/transcript.html

 - Ed Kyle
Title: Re: Challenger STS-51L
Post by: Ronpur50 on 01/30/2014 04:09 PM
While watching some of the memorial service on my DVDs yesterday, I saw Dick Scobee's son and wondered what ever happened to him.   Although time has seemed to stand still when I watch those images, it has moved on.  He is now Brigadier General Richard Scobee.  Commander Scobee would be 75 this year.  Wow.
Title: Re: Challenger STS-51L
Post by: Hoppytje on 01/31/2014 09:19 AM
Something new I read on the Wikipedia page of Mike Smith:
http://en.wikipedia.org/wiki/Michael_J._Smith_(astronaut)

" It has been claimed that his last words were, "Uh,oh". This is a false claim, based on a confused hearing of an in-studio analyst uttering these words at the time of explosion."

That's new to me. I always thought that "uh, oh", were his last words on the voice recorder.
Title: Re: Challenger STS-51L
Post by: spacecane on 01/31/2014 02:28 PM
Something new I read on the Wikipedia page of Mike Smith:
http://en.wikipedia.org/wiki/Michael_J._Smith_(astronaut)

" It has been claimed that his last words were, "Uh,oh". This is a false claim, based on a confused hearing of an in-studio analyst uttering these words at the time of explosion."

That's new to me. I always thought that "uh, oh", were his last words on the voice recorder.

That Wikipedia entry makes absolutely no sense.  The "uh oh" was part of the official transcript.  First of all, when doing audio analysis, they aren't watching the video.  Second, it's not like they listen once and write a transcript.  They listen over and over and do enhancements to determine what was said.

Also, somebody on the forum once posted that they were involved and actually heard the recording.  If I remember they described it as being not so calm as the transcript makes it sound.  Somebody should correct Wikipedia.
Title: Re: Challenger STS-51L
Post by: Thorny on 01/31/2014 02:35 PM
The "Uh oh" comment as the last words on the Challenger recording is also supported in the new book "Wheels Stop" in a passage where Rick Hauck (I think) admonished one of his crew for saying 'uh oh' during training, telling him to never utter the phrase again.
Title: Re: Challenger STS-51L
Post by: eeergo on 02/26/2014 07:23 AM
Reading through the "what-if" scenarios in this thread and other references, I came up with a slightly different thought experiment that I haven't seen analyzed before.

Suppose the propellant "pseudo-seal" in the SRB joint rupture hadn't formed at all at ignition, or just was too weak to be sustained for the 73 seconds it lasted in reality. From the accident report, it took around 15 seconds from the first flame coming out of the damaged SRB to total ET failure. If the flame had started at ignition, and assuming the plume behavior wasn't too affected by the lower speeds, that would put the ET failure right around the middle of the roll maneuver. Of course, one can imagine a seal that lasted a few seconds but failed soon after. The point is, what would have happened if the stack hadn't blown up in the pad, but the ET failed before it reached high speeds?

It has been argued before that an RTLS abort wouldn't have been possible in any case before SRB jettison, since otherwise they would have impinged on the orbiter/ET causing extensive damage, due to the jettisoning event making them diverge from the stack, which under full power would direct the exhaust directly on it. Or the orbiter would have crashed onto the ET, or both.

However, if they were not jettisoned but *released* in a similar event to the ET failure that happened in 51L, it appears they would swivel forward, converging towards one another and sending the exhaust outwards. Of course, the ET would already not be there for the orbiter to crash into. This would leave the orbiter to "just" deal with the effects of the hydrogen-oxygen detonation, assuming the SRBs managed to rocket out of there without hitting anything else, and assuming the MPS turbopumps would have enough time to stop without causing too much damage to the orbiter's aft (plausible?). In this early failure scenario, lacking the dispersive forces that it encountered at T+75s, and having more propellant left to burn, the detonation would probably have affected the orbiter more severely, but I don't know if this has been studied.

Then, if the detonation was survivable for the orbiter to keep certain maneuverability, it would emerge at around 2500 feet and a speed of 220mph. Would the aerodynamic environment in those conditions prevent breakup? If so, would this situation make it concievable, with luck on their side, to give some margin for a controlled glide to land somewhere in the Cape or ditch non-destructively into the ocean?

Of course, what happened happened, and may those brave souls rest in peace. For better or worse though, accidents like these make you want to know all their technical intricacies.
Title: Re: Challenger STS-51L
Post by: spacecane on 02/27/2014 11:48 AM
Although I'm not an expert, I don't think there is any chance that the Orbiter would have had the aerodynamic authority to maneuver from vertical to horizontal at low speed.  I'm not sure a fighter jet could take off, climb vertically, shut off the engine at 2500 feet and make a horizontal landing.

The only way I can see that there may have been a different outcome for the crew is for something to have happened very close to the ground so that the only issues to deal with were the fire and SRB exhaust and self destruct and not the impact force of the crash.
Title: Re: Challenger STS-51L
Post by: eeergo on 02/28/2014 01:14 AM
Although I'm not an expert, I don't think there is any chance that the Orbiter would have had the aerodynamic authority to maneuver from vertical to horizontal at low speed.  I'm not sure a fighter jet could take off, climb vertically, shut off the engine at 2500 feet and make a horizontal landing.

The only way I can see that there may have been a different outcome for the crew is for something to have happened very close to the ground so that the only issues to deal with were the fire and SRB exhaust and self destruct and not the impact force of the crash.

Residual thrust from the SSMEs should push the tail of the orbiter forward, pitching the nose down. Whether that force could be overcome by the ET deflagration (although most of its contents were pouring down, rather than radially), or if there were any conditions under which it wouldn't lead to an uncontrollable pitch or other non-recoverable situations, is something I don't have a clue about, but probably someone in these forums has a good idea of what could be expectable.

The fighter jet analogy is valuable (for someone who knows what fighter jets can or cannot do, which I don't), but one going straight up and shutting of the engine at 2500ft won't have the same speed as a shuttle lifting off (or the same inertia) - 220mph is about their nominal touchdown speed.

On the other hand, your scenario close to the ground may be survivable if the fire didn't affect the crew cabin too much: the crew cabin free-falling from a height close to the liftoff one would reach ~100km/h, higher speeds could be survivable being well strapped on. But an instantaneous failure is further from what really happened than an relatively small-scale O-ring failure since ignition, IMO.
Title: Re: Challenger STS-51L
Post by: spacecane on 02/28/2014 01:07 PM


Residual thrust from the SSMEs should push the tail of the orbiter forward, pitching the nose down. Whether that force could be overcome by the ET deflagration (although most of its contents were pouring down, rather than radially), or if there were any conditions under which it wouldn't lead to an uncontrollable pitch or other non-recoverable situations, is something I don't have a clue about, but probably someone in these forums has a good idea of what could be expectable.

Since I believe the SSME thrust vector would be pointed towards the CG of the stack I think the residual thrust would flip the orbiter "backwards" into a spin of some sort.  My fighter analogy was more an aerodynamic control speculation.  I don't think there would be enough speed/altitude to be able to aerodynamically control the orbiter starting in a vertical orientation if an event happened at 2500 ft.
Title: Re: Challenger STS-51L
Post by: MikeEndeavor23 on 01/04/2015 02:12 AM

    Interesting thread,

     I found a couple of interesting videos on youtube that might be of interest.  One is Dan Germany's testimony in front of the Space Science Tech Committee.

https://www.youtube.com/watch?v=-49-hDXgpG4

MikeEndeavor23
Title: Re: Challenger STS-51L
Post by: MattMason on 01/14/2015 02:10 PM
This thread must remain ageless.

I was in my third year of college, coming home from class when I overhead a TV in the dorm. I ran into a stranger's room to see. A long-time space enthusiast and familiar with STS design, my first reaction cursed the External Tank, which I thought had ruptured.

Like many others both amateur and professional, the truths behind the STS design and its inherent flaws became reality as the Commission concluded and released their reports. While many changes were made, none of them helped Columbia's later demise, affirming the STS design to many (particularly it's Commission) as inherently experimental.

Getting back to capsule designs such as Orion, Dragon and CST-100 seemed instinctively backward to some, until you also take in the lessons of the past. Space is still a pioneering effort and escape to safety is just as important as getting there.

The thing that always gets me about the Challenger incident stems from my enjoyment of science fiction. As NASA finally readied OV-102 for the STS maiden flight, a decision was made not to refurbish OV-101, Enterprise, the first Orbiter used for the Approach and Landing Tests, deeming it too expensive to refit her.

As we know, OV-101 was originally to be named Constitution but, ostensibly through pressure from fans of the TV show, "Star Trek," President Ford authorized the renaming to the popular fictional starship, although others say it was named after the distinguished 19th Century schooner and World War II carrier.

With Enterprise left for ground tests, cannibalizing of her usable parts and later to be hauled off to a museum, a high-fidelity Orbiter aeroframe and structural test article, STA-099, was refitted to replace Enterprise, as OV-099, Challenger.

The pain and anguish on that day in 1986 might have become greatly magnified were it Enterprise that shattered in the skies that day.
Title: Re: Challenger STS-51L
Post by: jacqmans on 01/21/2016 07:58 AM
January 20, 2016

RELEASE J16-002

Maine Native and NASA Astronaut Honors Space Shuttle Challenger Astronauts

Maine’s newest NASA astronaut, Jessica Meir, will commemorate the 30th anniversary of the final space shuttle Challenger mission at events scheduled for Jan. 27-28, hosted at the Challenger Learning Center of Maine.

Selected in 2013 as part of the 21st astronaut class, Meir recently completed her astronaut candidate training and is now qualified for mission assignment. Meir is serving currently as a spacecraft communicator (CAPCOM) supporting the Mission Control Center in Houston, Texas, and crews onboard the International Space Station. Born and raised in Caribou, Maine, she earned a bachelor’s degree in biology from Brown University, a master’s in space studies from International Space University, and a doctorate in marine biology from Scripps Institution of Oceanography.

“I remember exactly where I was on that day 30 years ago, excitedly watching the launch countdown along with my third-grade classmates in Caribou, Maine,” Meir said.  “The tragic loss of the crew is something we will always remember and carry in our hearts. I know these astronauts would have been proud of the global network of centers created in their memory, dedicated to inspiring students through unique educational experiences.”

The Challenger Learning Center, located in Bangor, Maine, will host middle school students from across the state for a special presentation by Meir at the Collins Center for the Arts, Jan. 27. The student-only event will be followed by an after-school open house at the Challenger center, in collaboration with the Maine Science Festival. Members of the public are welcome to meet Meir and tour the center. Meir also will be the keynote speaker at a special reception for invited guests at the Challenger Center later that evening.

The morning of Jan. 28, local members of the media are invited to register for live interviews with Meir at the Challenger Center. Interested media may schedule an interview by contacting Susan Jonason, the center’s executive director, by email at [email protected]

“The families of the Challenger crew created the Challenger Centers to continue their education mission through space-themed learning and role-playing strategies to help bring students’ classroom studies to life and cultivate skills needed for future success”, Jonason said. “We feel very fortunate to have one of these wonderful centers right here in Bangor.”

For event details and more on the Challenger Learning Center of Maine, visit:

https://www.astronaut.org/

For more information on Meir, visit:

http://www.jsc.nasa.gov/Bios/htmlbios/meir-ju.pdf

Follow her on Twitter: @Astro_Jessica

To learn more about NASA’s education resources, visit:

http://www.nasa.gov/offices/education/programs/national/ercn/home/
Title: Re: Challenger STS-51L
Post by: kking on 01/22/2016 03:11 PM
I just found a live coverage of 51L launch.

https://www.youtube.com/watch?v=eGLCB6Cl-VY

Title: Re: Challenger STS-51L
Post by: joema on 01/24/2016 09:46 PM
National Geographic Channel will be showing a documentary this week about STS-51L. It is titled "Challenger Disaster: Lost Tapes". It apparently uses cinema verite techniques (no narrator, no interviews, no recreations) to factually explain the event using previously unseen archival footage.

http://www.natgeotv.com.au/tv/challenger-disaster-lost-tapes/

http://natgeotv.com/uk/challenger-disaster-lost-tapes/about

Link to trailer: http://tinyurl.com/zgkc7cx
Title: Re: Challenger STS-51L
Post by: Tony Trout on 01/26/2016 05:36 PM
National Geographic Channel will be showing a documentary this week about STS-51L. It is titled "Challenger Disaster: Lost Tapes". It apparently uses cinema verite techniques (no narrator, no interviews, no recreations) to factually explain the event using previously unseen archival footage.

http://www.natgeotv.com.au/tv/challenger-disaster-lost-tapes/

http://natgeotv.com/uk/challenger-disaster-lost-tapes/about

Link to trailer: http://tinyurl.com/zgkc7cx


I saw that last night.  Wasn't really impressed with it.  It just basically showed the time leading up to the launch,the pick of Christa as the first teacher and tried to explain why Challenger exploded - which was because of two factors:  The temperature at launch and the failure of the O-Rings to do their job and seal the insides of the SRBs like they were supposed to. 


Where was everyone when it happened? I was just a little kid, but I remember the newsflash as it interupted a kids show I was watching.


I was home from school for a teacher workday and watched the entire thing.  When the voice came over the loudspeakers at KSC that said, "Obviously, a major malfunction", those words really made me angry because they apparently couldn't tell that the Challenger had blown up at that point.  From past Shuttle missions, they should have known that the huge plume of smoke wasn't just SRBs separating.  It's ironic but as soon as I saw that one ball of fire ignite from the right SRB, I knew there was gonna be a horrific accident.

The late Roger Boisjoly, formerly with Morton-Thiokol, knew that the Challenger shouldn't have launched in that cold air because the O-Rings wouldn't seal properly. 

Were NASA that launch-trigger happy that they didn't care about the safety of the six astronauts and one civilian (Christa McAuliffe) on board the shuttle that day?   >:(  NASA apparently thought, "We've done it before with no problems.  I don't see a problem with launching at these temperatures?"  Boy, were they wrong......:(

I'm just honestly wondering.....

Title: Re: Challenger STS-51L
Post by: LaunchedIn68 on 01/26/2016 11:57 PM


[/quote]
When the voice came over the loudspeakers at KSC that said, "Obviously, a major malfunction", those words really made me angry because they apparently couldn't tell that the Challenger had blown up at that point.  From past Shuttle missions, they should have known that the huge plume of smoke wasn't just SRBs separating. [/quote]

Well no, they couldn't tell that it broke up because they're not looking at the TV first off.  Their eyes are glued to their screens monitoring data, and only knew SOMETHING was wrong when they lost all downlink.  In the video of Rick Hauck at CAPCOM, you see him glance at the TV that was there with an incredulous look on his face.  He's stated that he was looking at his data on the screen, and only because a flash of light on the TV next to him, in his peripheral vision caused him to look over and see the plume.  No one that day in Mission Control expected an explosion.  An engine loss resulting in an RTLS/TAO sure, multitude of alarms or systems going offline yes, any number of scenarios they simulated to react to.  Remember, they weren't privy to the conversation the night before between management and Thiokol.

"Obviously, a major malfunction" yes not the best choice of words but what DO you say at a time like that?

I personally liked the show.  The disaster has been covered and recovered so many times in documentaries and books etc..., that  I know the entire analysis inside and out.  But watching the video clips from those days, brought me back 30 years to that day when I came home as a high school senior, from a half day of school for taking an English midterm exam.  I thought it was well done and was a welcome change.  The details are covered elsewhere.  I would have liked some more on the other crewmembers though.
Title: Re: Challenger STS-51L
Post by: joema on 01/27/2016 02:58 PM
...I saw that last night.  Wasn't really impressed with it.  It just basically showed the time leading up to the launch,the pick of Christa as the first teacher and tried to explain why Challenger exploded - which was because of two factors:  The temperature at launch and the failure of the O-Rings to do their job and seal the insides of the SRBs like they were supposed to....

The documentary was an archival cinema verite piece (no narration, no voiceover) which is a highly constrained format. It is considered more "pure" from a documentary standpoint. I agree it felt limited but that is the nature of this presentation style. Cinema verite expects viewers to simply accept what can be presented in that narrow style, rather than narration, graphics and interviews leading you by the hand to an editorial position.

I am surprised they did not include the available footage and crew dialog from the P3 Orion "Cast Glance" photographic plane which tracked the SRBs.

For anyone interested in deep technical and procedural aspects, by far the most detailed account of the disaster and history of the SRB program is "Truth, Lies, and O-Rings: Inside the Space Shuttle Challenger Disaster", by Allan J. McDonald.

McDonald discusses what happened and implications for engineering ethics in this interview: https://www.youtube.com/watch?v=7_I-WUQvbjM (https://www.youtube.com/watch?v=7_I-WUQvbjM)

While a different incident, the transcript of the Columbia Accident Investigation Board (CAIB) from 4-23-03 is very educational, in particular statements by Robert F. Thompson, the shuttle program manager from inception to first flight. It covers key shuttle development decisions, development costs, planned flight rate, etc (do right-click and save as): https://www.nasa.gov/columbia/caib/PDFS/VOL6/H08.PDF (https://www.nasa.gov/columbia/caib/PDFS/VOL6/H08.PDF) If problems opening this, use top-level link and select "H.8 April 23,2003 Houston,Texas" : https://www.nasa.gov/columbia/caib/html/VOL6.html (https://www.nasa.gov/columbia/caib/html/VOL6.html)
Title: Re: Challenger STS-51L
Post by: Tony Trout on 01/27/2016 06:02 PM
.....at any point during the launch and flight of Challenger that anything was wrong?  Has it ever been published as to what the crew experienced when the accident happened? 

I know that sounds morbid and probably is.....but it's something I've always been curious about.
 

Title: Re: Challenger STS-51L
Post by: Rocket Science on 01/27/2016 06:23 PM
.....at any point during the launch and flight of Challenger that anything was wrong?  Has it ever been published as to what the crew experienced when the accident happened? 

I know that sounds morbid and probably is.....but it's something I've always been curious about.

Difficult reading...
http://www.spacesafetymagazine.com/space-disasters/challenger-disaster/
http://spaceflightnow.com/challenger/timeline/

http://er.jsc.nasa.gov/seh/explode.html
http://www.spaceacts.com/howdied.htm

In case you don't know/remember Dr. Joe Kerwin:

http://www.jsc.nasa.gov/Bios/htmlbios/kerwin-jp.html
Title: Re: Challenger STS-51L
Post by: woods170 on 01/27/2016 06:27 PM
.....at any point during the launch and flight of Challenger that anything was wrong?  Has it ever been published as to what the crew experienced when the accident happened? 

I know that sounds morbid and probably is.....but it's something I've always been curious about.
 



I suggest you read the report of the Rogers commission:

http://history.nasa.gov/rogersrep/genindex.htm
or on this forum as pdf (in the first post): https://forum.nasaspaceflight.com/index.php?topic=8535.0
Title: Re: Challenger STS-51L
Post by: hygoex on 01/28/2016 12:12 AM
Had the windshear not been present, would the accident possibly have been avoided?
Title: Re: Challenger STS-51L
Post by: catdlr on 01/28/2016 06:52 AM
30 years later, Challenger widow tells her story

Article and video

https://www.yahoo.com/katiecouric/30-years-later-challenger-widow-tells-her-story-140818583.html

Quote
“I often say that we were tremendously excited, the whole bunch of us were tremendously excited that we were kind of on this major interstate highway moving toward the heavens,” says June Scobee Rodgers, remembering Jan. 28, 1986, the day her husband, Cmdr. Dick Scobee, boarded the Challenger space shuttle.

“And then this terrible, numbing accident happened,” she says. “And he just kept on going toward heaven. And he left me dangling at the edge of that highway.”
Title: Re: Challenger STS-51L
Post by: Ronpur50 on 01/28/2016 11:34 AM
30 years later, Challenger widow tells her story

Article and video

https://www.yahoo.com/katiecouric/30-years-later-challenger-widow-tells-her-story-140818583.html

Quote
“I often say that we were tremendously excited, the whole bunch of us were tremendously excited that we were kind of on this major interstate highway moving toward the heavens,” says June Scobee Rodgers, remembering Jan. 28, 1986, the day her husband, Cmdr. Dick Scobee, boarded the Challenger space shuttle.

“And then this terrible, numbing accident happened,” she says. “And he just kept on going toward heaven. And he left me dangling at the edge of that highway.”

I watched that, and it was a great tribute.  But I was struck by the realization when I see June Scobee Rodgers, that 30 years have indeed passed.  I always remember her in the video with President Reagon at Houston. 

Dick Scobee would have been 76.  They have stayed young in our minds, while the rest of us have gotten old.  I wish they had gotten old with us.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 01/28/2016 12:48 PM
Chris Gebhardt's article to mark the 30th anniversary:
http://www.nasaspaceflight.com/2016/01/the-challenger-seven-remembered-51l/
Title: Re: Challenger STS-51L
Post by: MattMason on 01/28/2016 01:03 PM
Had the windshear not been present, would the accident possibly have been avoided?

No.

At ignition of the SRBs, the O-ring joint of the key Solid Rocket Booster immediately failed, blowing hot gases through to begin the degradation of the rest of the seals. It temporarily sealed itself for a few seconds before it reopened and became a blowtorch that tore out the bottom of the External Tank. This is shown in both video and stills of a black puff of smoke at the affected area.

In any case, once the SRBs are ignited, there were no abort options for the launch vehicle until SRB separation. From my understanding, an Orbiter attempting to break from the ET while under SRB power would shatter its airframe just as Challenger did on ET detonation.
Title: Re: Challenger STS-51L
Post by: Chris Bergin on 01/28/2016 02:05 PM
Chris Gebhardt's article to mark the 30th anniversary:
http://www.nasaspaceflight.com/2016/01/the-challenger-seven-remembered-51l/

And that's getting a lot of deserved attention. BBC Radio having Chris on very shortly to talk about Challenger.
http://www.bbc.co.uk/radio/watchlive/5live
Title: Re: Challenger STS-51L
Post by: Hog on 01/28/2016 02:27 PM
Had the windshear not been present, would the accident possibly have been avoided?

No.

At ignition of the SRBs, the O-ring joint of the key Solid Rocket Booster immediately failed, blowing hot gases through to begin the degradation of the rest of the seals. It temporarily sealed itself for a few seconds before it reopened and became a blowtorch that tore out the bottom of the External Tank. This is shown in both video and stills of a black puff of smoke at the affected area.

In any case, once the SRBs are ignited, there were no abort options for the launch vehicle until SRB separation. From my understanding, an Orbiter attempting to break from the ET while under SRB power would shatter its airframe just as Challenger did on ET detonation.
It's my understanding that the re sealed failure was broken loose during the largest windshear experienced during STS.  The first puffs of smoke occurred at T+ 0.6 seconds and occurred at the same frequency as residual "twang" motions until T+ 2.7 seconds 
The windshear was encountered at T+ 38 seconds  for approx. 27 seconds.
The plume from the leak was not noticed until T+ 58 seconds,
At T+60 the plume was well defined and was impinging upon the tank.
At T+ 64 the plume changed indicating the Hydrogen leaking
At T+66 seconds, the ET's indicated pressure dropped

That seal held for almost a minute.  Including the time where both the SSME's and the SRB's all throttle down and then throttle back up.  The SRB pressure was increasing from the Max Q throttledown from T+50 seconds through to breakup.
If that reseal did hold, chance are that no one would have known anything was wrong until the ascent film was viewed or until the SRBs were recovered and inspected.

I don't think that the phrase "if the windshear didn't occur, the outcome may have been different" can simply be discounted outright.  Of course that's my personal opinion, and of course we'll never know.

Highest respects to family and friends of all involved.
Title: Re: Challenger STS-51L
Post by: MattMason on 01/28/2016 02:32 PM
Thanks, Hog. There was an earlier flight with a O-ring blowback that did reseal itself and stay resealed, right? Turns out 51-L wasn't as lucky. Thanks for the clarification.
Title: Re: Challenger STS-51L
Post by: MattMason on 01/28/2016 03:28 PM
My thoughts on the incident:

I was attending Indiana University in Bloomington, Indiana, coming back from a class. I overheard a news broadcast as I made my way through a dorm hallway. I knew of the flight, tracking its launch time (and earlier delays) but knew I'd be in class at the time of launch. I had made a silent remembrance of Aoollo 1's 19th anniversary of its accident, 19 years and a day before.

I was quite familiar with the STS components and never liked what I thought was one flimsy component: the external tank. On seeing the explosion, I spat out an expletive, thinking that the ET had popped.

Turns out I was half-right. The ET popped because of the SRB blowtorch that cut a hole in its bottom dome.

That sensation of NASA being able to do little wrong since Apollo 1 disappeared.

The mood of the students and faculty was somber and confused. I found myself explaining some space terminology to those unfamiliar. I would not feel the same sense of mourning, anger, and confusion until September 11, 2001.

The year 1986 kept going with tragedy both worldwide and personal. The Chernobyl accident occurred a few months later in April. And as I was packing up the last of my things from my dorm room in May, I got a call about my father's death.

So if I had to do things over again, we can just skip 1986, personally.

But, but skipping things, we'd never learn and fix mistakes that would've doomed another Orbiter. It would've just happened to some other nice folks.
Title: Re: Challenger STS-51L
Post by: hygoex on 01/28/2016 07:07 PM
In the TV movie Challenger which I just looked at again, during the break in the pre-launch meeting with Thiokol, Cecil Houston got a call from the Coast Guard saying the booster recovery ships were in a "full gale" and headed back to port.  Any truth to this? 
Title: Re: Challenger STS-51L
Post by: ChrisGebhardt on 01/28/2016 07:33 PM
Thanks, Hog. There was an earlier flight with a O-ring blowback that did reseal itself and stay resealed, right?

Not quite. There were a couple of O-ring issues in the early phase of the program, but the one you're thinking of is STS-51C on the Shuttle Discovery.

Taken from one of our article in October 2015:

"During the 24 January 1985 launch of Shuttle Discovery on the STS-51C mission, ambient air temperature at the time of launch was just 53°F.

Post-flight recovery and inspection of the SRBs from STS-51C showed charring to the primary O-rings on both the left and right hand SRBs.

However, it was the burn path penetration through the primary O-ring on the center field joint of the right SRB from STS-51C, coupled with heavy charring on the secondary O-ring (indicating a near burn through event of the field joint), that provided a direct link to a mission one year and four days later."
Title: Re: Challenger STS-51L
Post by: JayJay on 02/01/2016 04:41 PM
Hypothetical question here and I apologize if this has been answered but I've searched and cannot find an answer to this.  I know that the SRBs continued to fire until they were destroyed by the SRO.  It only just occurred to me, what if the burn through had occurred in a "safer" location (ie. away from the ET and shuttle), could the shuttle have made it to SRB SEP?  I know that the shuttle engine gimbals and SRB gimbals had already started reacting to the SRB thrust asymmetry, but at what point would they have not been able to keep control of the stack?
Title: Re: Challenger STS-51L
Post by: Jim on 02/01/2016 04:49 PM
ET detonation.

Disintegration.  It did not blow up.  Once the propellants were released, there was a deflagration and not a detonation.  The ET came part from the hot gas impinging on it and the loads.
Title: Re: Challenger STS-51L
Post by: Jim on 02/01/2016 04:50 PM
In the TV movie Challenger which I just looked at again, during the break in the pre-launch meeting with Thiokol, Cecil Houston got a call from the Coast Guard saying the booster recovery ships were in a "full gale" and headed back to port.  Any truth to this? 

no
Title: Re: Challenger STS-51L
Post by: Jim on 02/01/2016 04:50 PM
Hypothetical question here and I apologize if this has been answered but I've searched and cannot find an answer to this.  I know that the SRBs continued to fire until they were destroyed by the SRO.  It only just occurred to me, what if the burn through had occurred in a "safer" location (ie. away from the ET and shuttle), could the shuttle have made it to SRB SEP?  I know that the shuttle engine gimbals and SRB gimbals had already started reacting to the SRB thrust asymmetry, but at what point would they have not been able to keep control of the stack?

unknown
Title: Re: Challenger STS-51L
Post by: Paul Howard on 08/04/2016 01:29 PM
Any plans to name any of the Orions after the fallen orbiters?
Title: Re: Challenger STS-51L
Post by: Jim on 08/04/2016 01:37 PM
Why? They are Orion.
Title: Re: Challenger STS-51L
Post by: WBY1984 on 08/25/2016 10:37 AM
How did the flames even reach the damaged joint? Isn't there a wall of unburned propellant between the hot combustion gasses and the joint, right up until burnout?
Title: Re: Challenger STS-51L
Post by: Jim on 08/25/2016 11:53 AM
How did the flames even reach the damaged joint? Isn't there a wall of unburned propellant between the hot combustion gasses and the joint, right up until burnout?

Not at the joints. Do a google search on the joint.
Title: Re: Challenger STS-51L
Post by: edkyle99 on 02/07/2017 02:27 AM
I worked STS-51L payload processing and was an eyewitness to the 1986 disaster.  The accident literally changed my life, steering me toward where I am today. 

This photo from ISS, and the story behind it, just floored me when I read it today.  My wife, a middle school teacher, said "wow" when she read the story.  (She usually doesn't say "wow" when I show her something space-related!)

http://www.collectspace.com//news/news-020617a-challenger-soccer-ball-space-station.html

#NASARemembers indeed.

 - Ed Kyle
Title: Re: Challenger STS-51L
Post by: catdlr on 06/24/2017 12:55 AM
STS-51L Challenger - Multi Angle Launch Footage


lunarmodule5
Published on Jun 23, 2017

STS-51L multi-launch angle coverage with audio from ABC Radio

https://www.youtube.com/watch?v=1YFrhpe0I7s?t=001

https://www.youtube.com/watch?v=1YFrhpe0I7s
Title: Re: Challenger STS-51L
Post by: Proponent on 11/01/2017 04:04 PM
During the Senate hearing just concluded on (among others) Rep. Brindenstine's nomination as NASA administrator (https://forum.nasaspaceflight.com/index.php?topic=39678.msg1744705#msg1744705), Sen. Nelson made what I believe to be a garbled reference to the Challenger accident.  Bashing Brindenstine's non-technical background, he said that the last time NASA lost a crew it was under the leadership of a non-technical administrator.  So far, so accurate:  Columbia was lost while accountant Sean O'Keefe was running NASA.  But Nelson then went on to talk about James Beggs, who was NASA administrator in the early and mid-1980s.  Sometime before the loss of Columbia, in what was described as a temporary move, Beggs stepped aside to defend himself against corruption charges related to an early position he had held at a defense contractor (and not only was eventually acquitted but received an apology from the government).

The point is that on the day of Challenger's fatal launch, Beggs was technically the administrator, but William Graham was acting administrator.  Nelson claimed (https://forum.nasaspaceflight.com/index.php?topic=39678.msg1744780#msg1744780) that Beggs, being aware of the low temperatures at the Cape, called NASA and begged it to cancel the launch.  Is that true?

It's odd that Nelson would get his facts wrong on this, since the Challenger accident followed his own Shuttle flight so closely.  I'd have thought the events of the time would be very clear in his mind, especially since his mistake only muddies his claim that non-technical NASA leadership is dangerous.