Michoud External Tanks May Hold Clue About Columbia Accident

Nasa, Michoud ^ | 2/4/2003 | Joseph Ranos

[XBob]

16 - "For what it is worth, I estimate that the BLOCK of ICE, clearly visible as white BEFORE it struck the left wing,"

Seems like this should be pretty easy to determine, ice or insulation (it sure looked like ice to me) by simple spectrographic analysis of the colors.

[XBob]

Excellent, and hard work Sonar5. Thankyou very much. You dug out and organized and quantified some very good info, and that is very hard to do with all the variables. 107 lashes with a wet noodle for each of your detractors.

23 - When I worked at KSC 88-91, the ET's came from the factory, by barge and were foamed at the factory.

Minor repairs for damage were done at KSC.

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Guys, Now, for some observations/points which may help or hinder, but please add to your already brimming thinking caps.

1. Sometime earlier this morning, in a daze between awake and dreaming, I thought I heard a spokesman (from somewhere, where I don't know) say that this tank had different insulation, which had a different gas component, and because of that, the gas expanded when losing atmospheric pressure, causing the foam cells to explode, like popcorn.

2. Sonar5, now this got me to thinking, and combined with your point about ages of the tanks, caused me to think about another serious shuttle problem we had during those years, and that was all the trouble we had water proofing the tiles on the shuttle, so they were protected from the rain/moisture.

3. KSC is located on the ocean, and NORMAL humidity is 95%, or higher. Moisture/humidity permeates everything, it's normal. The external tanks are stored in the Verticle Assembly Building, which is air conditioned, but each time one of the giant 500 foot tall doors is opened, it loses air conditioning. In fact, the humidity inside the building gets so great that it has been known to rain, inside the building. (no joke - guiness book of records I believe).

4. I have no idea if it has anything to do with the problem, but I would assume that gradually, even the driest of foam coatings would be permeated with moisture, just sitting there in storage. And then coupled with the humidity, there may be an aging/deterioration factor.

5. I pose the question - is there a relationship, between the time the tank sits in storage and the propensity of the insulation to perhaps make like popcorn and peel off?

[Atchafalaya]

It was also calculated that the speed of the foam impacting the shuttle was 61 mph (remember it was going as fast as everything else when it broke off); not at some hypervelocity as some would imply.

[GovernmentShrinker]

Do you think there may be a link between long storage time of the tank and propensity of the foam to break off at launch?

[Atchafalaya]

Dittmore said that the lwt used was one of two in the inventory on site at Canerveral.

[Al B.]

Dittmore said that the lwt used was one of two in the inventory on site at Canerveral.

For the record, I also heard him say that. He clearly said it was a LWT.

[GovernmentShrinker]

Yes, ET-94 hasn't flown yet (maybe it never will).

[jackbill]

Frankly, I gave up reading about a third of the way through. NASA said, two or more days ago, that the ET was the second to last LWT in their inventory. The SLWTs have been used for Shuttles going to the ISS, since it's orbit is higher than non-ISS Shuttle missions.

Secondly, this morning's NY Times hinted that the problem of peeling insulation from the ET started when - in order to be environmentally friendly - NASA stopped using freon in the production of the insulation.

[SirAllen]

Well, then we agree to disagree.

The facts are that it would take at least a month at the very earliest to get another shuttle up there - and that would be putting that shuttle at great risk. Soyuz was also out of the question. The fact remains that if Commander Husband was faced with a 100% certainty of death by remaining in orbit, and an unknown certainty of reentry, reentry would still have been the only choice. They may have remained in orbit 4 more days until their life support started running low, and then gave reentry a try but either way their death warrants were signed 81 seconds into the launch.

Sure, they would have gotten to say goodbye and we would have had a world wide drama and horror played out over multiple days that would have been much more painful. I don't know, if I was faced with the choice of knowing 4 days before I die that I was going to die, or not know, I'd choose not know. Also I think you assume too much that the families would like to have had that extra time. Again, if it was me I wouldn't have wanted that extra time. I couldn't handle the drama and emotion, it'd just make the inevitable worse.

[tubebender]

It would probaby not have broken your windshield, but might have cracked it and would have blown into thousands of fragments and dust.IMHO

If it wouldn't have broken a windshield how did it damage the tiles?

[GovernmentShrinker]

Those tiles are incredibly fragile.

[Ravenstar]

Apollo 13 Did not have a heat shield problem. We could have delayed maybe 5 days before they ran out of consumables, oxygen for example, they could not have changed orbital plane and gone to station because they did not have sufficient engine or fuel to do so. The beginning, I have not and wont read all of it right now, theory or suppositions until you get to your Apollo 13 comment is factual and well grounded and you allow for things to change in light of new facts. Keep going and you will get there.

Ravenstar

[Ravenstar]

You are correct on this point SirAllen at this time this is the case.

Ravenstar

[Cold Heat]

If it wouldn't have broken a windshield how did it damage the tiles?

That is what NASA is wondering about. They believed, as do I that the damage should not have been so severe to total the shuttle. It has landed safely before with over 300 damaged tiles.

Some fluke of nature or as yet unknown sequence of events occurred, or the object did something while it was behind the wing that we could not see.

[XBob]

5-"I'm sorry, but stating that you have spent "all morning" researching this topic (given its complexities) doesn't exactly inspire confidence.

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Well, Sonar5 certainly inspires a lot more than just confidence, especially when compared to a John from Manhattan.

[XBob]

Wow, thanks for clearing everything up. Can you create a winning strategy for the upcoming war...and perhaps design a fuel-cell vehicle before you leave work today?

No hollywood red, that would take Sonar5 at least a day for each of those problems.

Ever consider going into public relations? you give such fantastic compliments.

[Sonar5]

Two days Max, is all I need for those problems. ;-)

But I'm busy right now,

Regards,
Joe

[Libertina]

Sonar you have really worked diligently on researching this... I am reading and trying to digest it now.

[aquawrench]

"when that foam is combined with a flight velocity between speeds of MACH two to MACH four, it becomes a projectile with incredible damage potential."

Are you saying that when the foam came off, it was moving at zero mph? There had to be ice involved to mar the tiles so badly.

[Sonar5]

Hi,

Keep your eye on the ball here.

The debris was the cause, the tile damage was the effect.

Eliminate the cause (debris), no more tile problems. I still feel the tiles and the Shuttle are sound.

My concerns are the External Tanks.

If you saw any of the demonstrations with the tiles, you can do damage with a fingernail.

I mentioned a double-hull theory yesterday on another board. But what if it was, and then the insulation was sprayed on the inner hull, leaving the outer hull only weldelite, (The Alloy). If the Inner hull is very thin, this might be a solution. The ET right now is only a half inch thick.

It's just a thought, so feel free to bash me on its merits. And yes, of course weight is a consideration, but so should be lives.

Regards,
Joe