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NASA has set up this FTP site here for the public to use to upload photos, videos and documentary commentary of found debris. It may be the first use of the Net to assist in disaster evidence collection on such a massive scale. REMEMBER not to touch anything. And FORGET about trying to profit from this tragedy. February 4th, 2003 | One comment - (Comments are closed)
 I really don’t want to add anything to this statement by the families. If it doesn’t bring a tear to your eye, you have no soul. February 4th, 2003 | Comments are closed
Since Doug Jones uttered the name Henry Spencer in a recent comment, I decided to ring Henry and compare notes. A very interesting 15 minutes pooling our various bits of hearsay and rumour… Henry thinks a heat induced tireburst in the wing is one possible scenario. As we know (think Concorde) such events can be extremely violent and cause air frame damage. For my part, I note the best place to run the hydraulic loops from the APU’s is right through a section of rear fuselage and wing root where the news have been pointing to as places where the temperature rises were seen shortly before loss of communication. Neither of us knows exactly how the hydraulic lines run and how far apart their independant paths are. However the lines all have to come together at the actuators for the ailerons (or elevons since they can provide both functions I believe). Loss of the hydraulic loops would cause instant and violent loss of control, but I would expect at least a small amount of data showing the lines popping before the control loss occurs. I am not privy to any such data. Henry’s suggestion on the tire gives us a very sudden air frame damaging event, but unless it causes immediate catastrophic structural failure, I can’t see it happening without the crew knowing a few seconds in advance something was terribly wrong. I would expect clear signatures of either in telemetry. I guess we all have to say “we don’t know”, and we are at a disadvantage without access to the actual telemetry and time sequence. Which is of course what teams of engineers at NASA are most likely doing right now. Also, Henry reports from his sources that there is uncertainty that remains of all 7 have been found yet. They announced one way and then back tracked apparently. No one has found the significant heavy structures of the shuttle: the SSME’s or major portions of the crew pressure vessel. Something the size of a compact car is said to have gone down into a reservoir but it has not been found and no one knows what it was. The fact that remains have been found tells us the pressure vessel must have been split open. It is likely these items travelled the farthest. They could be deep into Louisiana or perhaps into the Gulf of Mexico. If the latter, there is the risk they will not be found for a very long time. Hopefully Henry will drop by and add his tuppence (Canadian) to these random jotting about our brief brainstorm. MORE: A 6-7ft long piece of the cabin has been found. Added to the evidence that astronaut remains have been found, I think it is safe to say the pressure vessel and contents were shredded pretty thoroughly. The good news is, more of it is likely to be found around Nacogdoches rather than further down range. There is still no word of the three SSME’s. STILL MORE The Indendant claims bits will still be turning up in ten years. Ten years hell: centuries more like. Not to mention the few odd bits that will make it into fossil layers to be dug up a hundred million years hence. We are talking about hundreds of thousands of shuttle bits spread over half of East Texas and potentially spread from California to Louisiana and the Gulf of Mexico. They’ll be lucky to even find all the big parts this side of 2100! AND MORE They have now found the nosecone February 3rd, 2003 | 9 comments - (Comments are closed)
Fox News today reported information given out by Shuttle program manager Ron Dittemore I find quite useful:
If you put this together with other information, the picture starts falling together. An amateur astronomer in California saw an orange trail before the shuttle crossed the US Pacific coast. This roughly matches up in time with the sensor data and I believe what this man saw was the ionization trail of material being burned off the port wing. I am unable to state what material it was, but perhaps someone who did more than barely pass Qualitative can suggest. I can only think of Potassium (K) and Sodium (Na) of course those would be likely constituents of the tiles (I think – I have not dug into literature to refresh my memory on the tile ceramic). I out right do not remember the colour of ionized Aluminum; there are many other possibilities as well, such as hydrazine or hydraulic leaks. But his description of “an L shape” makes me think of a tile or tiles unbonding and disintegrating into powder as they smash against the pitched up wing, and then being ionized into a burst of glowing plasma… followed by a steady erosion of surrounding tiles in the 3000F+ slipstream. A spectrogram would have been wonderful for the investigation team. His photos may well show the beginning of the end, the initiation of an unzipping of tiles. NOTE: The DOD sometimes uses the re-entering shuttle as a sensor test target for space defense systems. It is possible NASA is already getting such information. I have seen unclassified photos of a shuttle re-entry taken by experimental DOD optical systems. Such might exist this time as well. I have absolutely no way of knowing. This is pure (but “educated”) speculation on my part. STILL MORE: Doug Jones from XCOR may also have seen tiles disintegrating if I am right. He posted a comment here on Saturday:
February 3rd, 2003 | 3 comments - (Comments are closed)
Peggy Noonan hit the right tone. I think she understands the dream. And Buzz… I did to:
February 3rd, 2003 | 6 comments - (Comments are closed)
The Washington Post reports that remains of all seven crew members have been found. This will make it easier on the families. I hope they all get a missing man flyover. February 3rd, 2003 | 6 comments - (Comments are closed)
I’ve now seen more (but still sketchy) details on the telemetry timeline in the port wing. There is enough there for me to suggest another possible scenario. The first problem detected was a temperature rise in the port hydraulics. All the flight surfaces on the shuttle are controlled by hydraulics. Pressure is supplied by the APU’s; control is supplied by actuators controlled by the shuttle computers (GPC’s). There are 5 GPC’s. If I remember the architecture correctly, each controls a seperate hydraulic loop. If a GPC fails and tries to ram an aileron full down, the other 4 override it. This is not handled in electronics, it is handled in the hydraulics themselves. The pressure from 4 actuators pushed by hydraulics one way over rides the one going the other way. So long as no more than two GPC’s fail unsafe, control is still possible. Let’s posit a heat induced hydraulic failure in the port wing. The temperature rise is a common mode failure which overrides the redundancy. I do not know if they have any additional failsafe to return and lock the position of the aileron at a neutral position. However even if they did we can see a potential problem. The shuttle was in the second of two banks in an S curve the shuttle follows for bleeding off energy. Just at the time communication was lost. If the shuttle has just been commanded to roll and lost all hydraulics when put under the pressure by the actuators, we have the shuttle going into a roll that will go faster and faster. It seems likely (to me) we’d lose the aileron very quickly, followed by breakup within seconds. Even on level flight, I could imagine serious problems from complete loss of use of control surfaces on the port side. I doubt the fly by wire system could deal with something that extreme. I doubt you can fly a brick that way. Period. CORRECTION: After chatting with another knowledgeable friend and doing a bit of checking I found I was in error about the number of loops. There were 4 loops in the Enterprise drop test article; they apparently cut this down to three independant loops for the first flying article. February 2nd, 2003 | One comment - (Comments are closed)
I’ve noted a few interesting items as I’ve read through coverage this AM.
I think I will be calling it a night very soon as it has now passed 3am here in Belfast and I am starting to hear my mattress’ siren call; “come to me”. ONE MORE THING: If you can’t sleep and need reading material, you might find it interesting to relive the past. I believe all the discussions about the Challenger accident will be found in this 2.5 megabyte tar.gz file. Right click and download, Look for January 28th, 1986 and start reading from there. You might even recognize a few names. February 2nd, 2003 | 6 comments - (Comments are closed)
Fox News has a number of anecdotes from people who have reported on debris. The report includes some knowledge on the effects of spaceflight disasters I would rather have lived out my life without knowing. February 2nd, 2003 | 6 comments - (Comments are closed)
I’d have waited awhile, but the TV mediots are already trying to place the events of today into A Grand Context. They are speaking in sweeping generalization and grand predictions of Its Effect On America, The End Of The Space Station… and so forth. Yes there will be some effects, but primarily this is a human tragedy. We’ve lost some brave people and many of us empathize with the great vision and are saddened by the loss. But it is not going to cause any Earth shattering changes. It is not going to scar the national psyche. It is just a family funeral of loved ones in which we are all part of the extended family; those of us in the space community feel it perhaps more deeply than most but not nearly so much as their co-workers in Houston and Cape Canaveral or their families. With all of that said, I can now plunge into the punditry. The shuttles are going to be grounded for anything from months to a year. This will cause an enormous impact on the ISS scheduling. Completion will be thrown back by years. It is not only the loss of time while the fleet is grounded; it is the loss of capacity. Columbia was not much use for ISS missions and so it was useful for other non-ISS missions. Now those missions will have to be cut or serviced by the remaining fleet. That means a lengthening of the ISS completion time line. This can be somewhat ameliorated by giving the Russians a bundle of money to handle most of the supply trips. We can’t abandon the ISS for a long period of time. It must be reboosted at regular intervals because the vast solar arrays give it a lot of drag. There is a small amount of gas even at that altitude. Enough to slowly bring it down. So there is no real option of abandoning it for a couple years. You can’t. You also can’t risk bringing something that big into re-entry in one piece; and you can’t disassemble it without shuttle support. So NASA must get the fleet flying again. President Bush has already said we will not abandon space. In the community, we all knew that. It’s simply too important now. There will almost certainly be a push for a replacement vehicle. The shuttle is, after all, a 1975 base level of technology. It’s been upgraded and retro fitted, but even the newest shuttle, the Endeavour, is nearing 15 years old. The problems are budgetary and the inability of the “old aerospace” to perform on anything like a reasonable time and budget. I had actually much hoped NASA would work with the existing shuttles until the end of the decade, long enough to let the start up companies move in and revolutionize the field. NASA will go to Boeing or Lockmart for a replacement. They are not going to talk to XCor or Armadillo or any of the other companies who will develop the true space ships. What is my guess? I will suggest we’ll see a half hearted program for a shuttle replacement initiated. It will run over budget or be stillborn like every other such program in the last 15 years. The ISS schedule will stretch out to a completion date of 2010, almost 30 years after Ronald Reagan called for a space station to be completed in 10 years. An X-Prize space ship will fly suborbital this year or next year and there will be private tourists on private suborbital flights by 2006 and orbital by 2010. NASA will then buy one for crew turnaround. The Russians will get a big capital infusion to turn out more Soyez and Protons. The world will keep turning and the sky will stay firmly in place. February 1st, 2003 | 11 comments - (Comments are closed)
Time for a belated tea (I’ve been running on nuts and candybars all day) and the late news is on in a half hour. I’ll be back then with whatever new info I have. The main thing on my mind now is: “where did the crew compartment come down? Did it burn up and break up during re-entry or hit mostly intact? It’s a pretty sturdy bit of structure and about the only chance they’ll have for… well, humans don’t do so well in a re-entry plasma. Later. LATER: Networks seem to be far behind the blogosphere curve. Only thing new is that some partial remains have been found. They also suggested loss of a one of the control surfaces. While that would indeed cause loss of control and breakup, I see no reason for it to occur; and besides which, that port-side tire telemetry tells me a different story. So I’m still standing by my first scenario. ONE MORE THING: One of the TV shots clearly showed one of the re-entry engines from the back of one of the OHMS pods (those bumps in the back by the tail). So much of the debris came down more quickly than I thought, and that probably means it came down in much smaller pieces than I expected. I also am wondering what portion came down in the smoking field they showed. Nothing there was identifiable from the helicopter overview. February 1st, 2003 | 3 comments - (Comments are closed)
I’ve thought of one other scenario to add to my initial list. Since the Shuttle was a spacehab mission, the payload is likely to have been well forward. If the payload tie downs to the longerons were to have broken during the reentry, the payload would have slammed into the back and the payload doors. The vehicle would then break up as in the other scenarios. I rate this idea as extremely unlikely but worth tossing out for the sake of completeness. February 1st, 2003 | 14 comments - (Comments are closed)
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