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You Said:
'Have you established when and where this insulation is foamed on? I.e., does the fact that the tank was shipped to NASA in 2000 actually establish that the foam had been sitting on it all this time?"

Good Question. It is my understanding it is applied at the manufacturing facility in Louisiana. I have come across nothing that conflicts with that.

Regards,
Joe

Next question (since nobody else seems to be peppering you with questions):

Can you create a table starting with STS-86 (first mission where the new "environmentally friendly" foam was used) which shows: 1) tank class (LWT/SLWT), 2) foam type (old/new), 3) degree of tile damage (e.g. STS-87 & STS 107 "severe" (at least presumed so for STS-107)/"moderate"/"negligible"), and 4) possible other contributing factors to moderate or severe tile damage (e.g. STS-87 was first mission to perform the "roll to heads up" maneuver). I'm interested in how many missions have had the combination of new foam and old LWT tank.

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.

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?