Re: PAL ramp photos

On Sat, 13 Aug 2005 02:00:13 +0000, Craig Fink wrote:

> On Fri, 12 Aug 2005 18:47:49 -0700, snidely wrote:
>
>> You might check nasawatch.com or the Washington Post for comments by
>> June Malone, a spokeswoman for NASA's Marshall Space Flight Center in
>> Huntsville, Ala.
>>
>>
> http://www.washingtonpost.com/wp-dyn/content/article/2005/08/09/AR2005080901394.html
>
> <quote>
>
> June Malone, a spokeswoman for NASA's Marshall Space Flight Center in
> Huntsville, Ala., which manages the external tank, said she could not
> speak about investigators' findings but confirmed that workers at the
> Michoud plant at one point performed an abrading procedure "in the
> general vicinity" of the eventual failure. The aim was to smooth out a
> divot in the tank's foam, which is extremely heat-resistant but easily
> gouged.
>
> <end quote>
>
> Thanks.
>
> Hummm.
>
> Abrading procedure sounds like some sort of shallow surface repair.
>
> I still wonder if there may have been some deeper repair (or
> manufacturing process) that produced the perpendicular failure line?

Another name for an abrading procedure might be called a fairing
procedure. If the PAL ramp is faired (sanded flat) twice at different
times, any high spots during the second fairing procedure would show up as
"light" spots in the oxidation layer of the foam. If the PAL ramp was
faired properly the first time, high spots during the second fairing
procedure might indicate debonding below.

http://t2www.nasa.r3h.net/images/content/110206main_1119-ET-121__5808_3072x2048.jpg

Starting from (1) "light colored" forward intertank access repair, is the
(2) "light colored" divot repair spot and then (3) "slightly" discolored
debris origin site.

Makes me wonder what caused the divot at (2)? And, did it break or debond
the PAL ramp at (3)?

Just speculating.

When fairing a boat hull, sometimes they paint the hull (white primer)
then dust the hull with another paint (maybe red). They sand
the hull with a long flat board to remove the red paint. High spots
get sanded more, and low spots show up as red. Fairing compound is added
to the low spots. Then, they do it all again. After doing this a few times
the hull is really flat and fair.

--
Craig Fink
Courtesy E-Mail Welcome @ WeBeGood@xxxxxxxxx
.

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