[meteorite-list] A better link.. Re: Tile Glows

From: MexicoDoug <mexicodoug_at_meteoritecentral.com>
Date: Mon, 27 Jun 2011 12:57:26 -0400
Message-ID: <8CE030265E2EE9F-ED4-89B9_at_webmail-m019.sysops.aol.com>

Wow ! Nice links, James. Still aren't clear what the heat-exposed
surface looks like on a microscopic scale after use, but it certainly
sounds on paper like the tiles are near perfectly resistant/stable. Can
you imagine an artificial bolide made of a sphere of this material?

My favorite size, a basketball sized-sphere of it falling from orbit
would have the following characteristics:

1024 gram mass
59 mph (95 km/h) impact velocity
NOT TOO HOT AND NOT TOO COLD - BUT JUST RIGHT TO TOUCH!
...and apparently no ablation loss!

For comparison, a real inflated basketball, on the other hand would
theoretically be:

650 gram initial mass
47 mph (75 km/h) impact velocity, theoretically: if it could withstand
the atmospheric passage
but you'd end up with an exploded smelly burnt cinder instead that you
wouldn't reallyb want to touch ;-)
...if not complete ablation loss!

This stuff is only 57% heavier than the bulk density of an inflated
basketball! Space Hoops, anyone ... what possibilities!

Best wishes
Doug




-----Original Message-----
From: James Beauchamp <falcon99 at sbcglobal.net>
To: cdtucson at cox.net; meteoritemike at gmail.com; John at Cabassi.net;
rickmont at earthlink.net; MexicoDoug <mexicodoug at aim.com>
Cc: Meteorite-list at meteoritecentral.com
Sent: Mon, Jun 27, 2011 7:58 am
Subject: A better link.. Re: [meteorite-list] Tile Glows




http://science.ksc.nasa.gov/shuttle/technology/sts-newsref/sts_sys.html


The?HRSI?tiles are made of a low-density, high-purity silica
99.8-percent amorphous fiber (fibers derived from common sand, 1 to 2
mils thick) insulation that is made rigid by ceramic bonding. Because
90 percent of the tile is void and the remaining 10 percent is
material, the tile weighs approximately 9 pounds per cubic foot. A
slurry containing fibers mixed with water is frame-cast to form soft,
porous blocks to which a collodial silica binder solution is added.
When it is sintered, a rigid block is produced that is cut into
quarters and then machined to the precise dimensions required for
individual tiles.
HRSI tiles vary in thickness from 1 inch to 5 inches. The variable
thickness is determined by the heat load encountered during?entry.
Generally, the?HRSI?tiles are thicker at the forward areas of
the?orbiter?and thinner toward the?aft?end. Except for closeout areas,
theHRSI?tiles are nominally 6- by 6-inch squares. The?HRSI?tiles vary
in sizes and shapes in the closeout areas on the?orbiter.
The?HRSI?tiles withstand on-orbit cold soak conditions, repeated
heating and cooling thermal shock and extreme acoustic environments
(165 decibels) at launch.
For example, an?HRSI?tile taken from a 2,300 F oven can be immersed in
cold water without damage. Surface heat dissipates so quickly that an
uncoated tile can be held by its edges with an ungloved hand seconds
after removal from the oven while its interior still glows red.
The?HRSI?tiles are coated on the top and sides with a mixture of
powdered tetrasilicide and borosilicate glass with a liquid carrier.
This material is sprayed on the tile to coating thicknesses of 16 to 18
mils. The coated tiles then are placed in an oven and heated to a
temperature of 2,300 F. This results in a black, waterproof glossy
coating that has a surface emittance of 0.85 and a solar absorptance of
about 0.85. After the ceramic coating heating process, the remaining
silica fibers are treated with a silicon resin to provide bulk
waterproofing.
Note that the tiles cannot withstand airframe load deformation;
therefore, stress isolation is necessary between the tiles and
the?orbiter?structure. This isolation is provided by a strain isolation
pad. SIPs isolate the tiles from the orbiter's structural deflections,
expansions and acoustic excitation, thereby preventing stress failure
in the tiles. The SIPs are thermal isolators made of Nomex felt
material supplied in thicknesses of 0.090, 0.115 or 0.160 inch. SIPs
are bonded to the tiles, and the SIP and tile assembly is bonded to
the?orbiterstructure by an RTV process.
Nomex felt is a basic aramid fiber. The fibers are 2 deniers in
fineness, 3 inches long and crimped. They are loaded into a carding
machine that untangles the clumps of fibers and combs them to make a
tenuous mass of lengthwise-oriented, relatively parallel fibers called
a web. The cross-lapped web is fed into a loom, where it is lightly
needled into a batt. Generally, two such batts are placed face-to-face
and needled together to form felt. The felt then is subjected to a
multineedle pass process until the desired strength is reached. The
needled felt is calendered to stabilize at a thickness of 0.16 inch to
0.40 inch by passing through heated rollers at selected pressures. The
calendered material is heat-set at approximately 500 F to thermally
stabilize the felt.
The RTV silicon adhesive is applied to the?orbiter?surface in a layer
approximately 0.008 inch thick. The very thin bond line reduces weight
and minimizes the thermal expansion at temperatures of 500 F
during?entry?and temperatures below minus 170 F?on orbit. The tile/SIP
bond is cured at room temperature under pressure applied by vacuum bags.
Since the tiles thermally expand or contract very little compared to
the?orbiter?structure, it is necessary to leave gaps of 25 to 65 mils
between them to prevent tile-to-tile contact. Nomex felt material
insulation is required in the bottom of the gap between tiles. It is
referred to as a filler bar. The material, supplied in thicknesses
corresponding to the SIPs', is cut into strips 0.75 inch wide and is
bonded to the structure. The filler bar is waterproof and
temperature-resistant up to approximately 800 F, topside exposure.
SIP introduces stress concentrations at the needled fiber bundles. This
results in localized failure in the tile just above the RTV bond line.
To solve this problem, the inner surface of the tile is densified to
distribute the load more uniformly. The densification process was
developed from a Ludox ammonia-stabilized binder. When mixed with
silica slip particles, it becomes a cement. When mixed with water, it
dries to a finished hard surface. A silica-tetraboride coloring agent
is mixed with the compound for penetration identification. Several
coats of the pigmented Ludox slip slurry are brush-painted on the
SIP/tile bond interface and allowed to air-dry for 24 hours. A heat
treatment and other processing are done before installation. The
densification coating penetrates the tile to a depth of 0.125 inch, and
the strength and stiffness of the tile and SIP system are increased by
a factor of two.
There are two different densities of?HRSI?tiles. The first weighs 22
pounds per cubic foot and is used in all areas around the nose and main
landing gears, nose cap interface,?wing?leading edge, RCC/HRSI
interface, external tank/orbiter umbilical doors, vent doors
andvertical stabilizer?leading edge. The remaining areas use tiles that
weigh 9 pounds per cubic foot.

--- On Sun, 6/26/11, MexicoDoug <mexicodoug at aim.com> wrote:


From: MexicoDoug <mexicodoug at aim.com>
Subject: Re: [meteorite-list] Tile Glows
To: falcon99 at sbcglobal.net, cdtucson at cox.net, meteoritemike at gmail.com,
John at Cabassi.net, rickmont at earthlink.net
Cc: Meteorite-list at meteoritecentral.com
Date: Sunday, June 26, 2011, 11:36 PM


Richard, James, very cool ... and especially being a witness of history
in the making for you guys ...

Does anyone know if these tiles show any signs of fusion (Is there
evidence of a fusion crust in this material or is is so structurally
pure and aerodynamically designed that a tile in proper service never
reaches a temperature for that to occur) as they wear out, or how
exactly material disappears as they wear out in old age (vs. a defect)?

Best wishes
Doug


-----Original Message-----
From: James Beauchamp <falcon99 at sbcglobal.net>
To: cdtucson at cox.net; 'Michael Gilmer' <meteoritemike at gmail.com>;
'MexicoDoug' <mexicodoug at aim.com>; John.L.Cabassi <John at Cabassi.net>;
Richard Montgomery <rickmont at earthlink.net>
Cc: Meteorite-list at meteoritecentral.com
Sent: Mon, Jun 27, 2011 12:00 am
Subject: Re: [meteorite-list] Tile Glows




Yes, I remember the demonstration repeated many times on broadcast TV
prior to the first launch. ?About ten seconds after it was orange, he
reached over and picked it up.



--- On Sun, 6/26/11, Richard Montgomery <rickmont at earthlink.net> wrote:


From: Richard Montgomery <rickmont at earthlink.net>
Subject: [meteorite-list] Tile Glows
To: cdtucson at cox.net, "'Michael Gilmer'" <meteoritemike at gmail.com>,
"'MexicoDoug'" <mexicodoug at aim.com>, "John.L.Cabassi" <John at Cabassi.net>
Cc: Meteorite-list at meteoritecentral.com
Date: Sunday, June 26, 2011, 10:50 PM


Long before the first Shuttle mission, I recall being somewhere at a
party
where some fella pulled out of his back-pack what he called a
Heat-Tile...and proceeded to give a demonstration:? he literally held
the
tile in his hand and fired it with an acetylene torch.? The torch-side
glowed red-hot and he still held it in his hand.

Then the Space Shuttle.

Back then (1978-maybe80???)

I mention this because I witnessed it in private hands before anyone
"publically" knew of the technology....shedding some light upon 'widely
gurded secrets.'

Back then I was into frisbee freestyle and remembering my undergraduate
degree was sort of important....wasn't taking many notes.

Pondering "before-factors" and more,
Richard Montgomery




----- Original Message -----
From: <cdtucson at cox.net>
To: "'Michael Gilmer'" <meteoritemike at gmail.com>; "'MexicoDoug'"
<mexicodoug at aim.com>; "John.L.Cabassi" <John at Cabassi.net>
Cc: <Meteorite-list at meteoritecentral.com>
Sent: Sunday, June 26, 2011 9:50 AM
Subject: Re: [meteorite-list] Moon Dust


> Blaine Reed had an actual shuttle tile in his room at the Gem show. I
> don't recall the price.
> This was a real actual tile with numbers on it indicating where it
went on
> the shuttle not just the material used to make real tiles as
indicated on
> this web site.
> Blaine's was significantly more expensive because it was real but, I
don't
> think it was flown in space.
> I was able to hold it. It weighs almost nothing. It feels like you
are
> holding chalk, NOT ceramic tile.
> Carl
>
> Meteoritemax
> .
> --
>
>
>
>
>
> "Democracy is two wolves and a lamb voting on what to have for
dinner.
> Liberty is a well-armed lamb contesting the vote".
>
>
>
>
>
>
>
>
>
> ---- "John.L.Cabassi" <John at Cabassi.net> wrote:
>> http://www.thespaceshop.com/shuttilin.html
>>
>> -----Original Message-----
>> From: meteorite-list-bounces at meteoritecentral.com
>> [mailto:meteorite-list-bounces at meteoritecentral.com] On Behalf Of
>> Michael Gilmer
>> Sent: Sunday, June 26, 2011 8:20 AM
>> To: MexicoDoug
>> Cc: Meteorite-list at meteoritecentral.com
>> Subject: Re: [meteorite-list] Moon Dust
>>
>>
>> Hi Doug and List,
>>
>> Doug - it is great to see you posting again.? I have missed your
>> insights.? :)
>>
>> They are selling heat tiles from the shuttles at KSC?? I didn't know
>> that, and I want one!
>>
>> I've been meaning to acquire some more space-related items - aerogel,
>> heat shield tiles, etc.
>>
>> Do they have a website where I can order the tiles, or do I need to
>> visit the gift shop in person?
>>
>> Best regards,
>>
>> MikeG
>>
>> PS - is there somewhere online to buy the Russian tiles also?
>>
>> --
>>
------------------------------------------------------------------------
>> ---------
>> Galactic Stone & Ironworks - Meteorites & Amber (Michael Gilmer)
>>
>> Website - http://www.galactic-stone.com
>> Facebook - http://tinyurl.com/42h79my
>> News Feed - http://www.galactic-stone.com/rss/126516
>> Twitter - http://twitter.com/galacticstone
>> EOM -
http://www.encyclopedia-of-meteorites.com/collection.aspx?id=1564
>>
------------------------------------------------------------------------
>> ---------
>>
>> On 6/25/11, MexicoDoug <mexicodoug at aim.com> wrote:
>> > JG wrote to MG:
>> > "What law are you talking about?"
>> >
>> > Ditto! A fact-supported discussion would be so much nicer.
>> >
>> > It is my understanding that when Apollo lost its funding, oodles of
>> > relics entered the private domain and there wasn't much ado about
it -
>>
>> > rather, a tacit acceptance and a party atmosphere pervaded in the
wake
>>
>> > of Moonphoria and non had any scientific value at the time. Where
are
>> > the retroactive vigorous sting operations hunting down these
national
>> > treasures? I am sure the same "laws", whatever they might be, cover
>> > them.
>> >
>> > Post-facto contrived rules are a violation which seems to date to
the
>> > Magna Carta and any remotely civilized society. All material
loaned or
>>
>> > provided in exchange for analyses to be done which is covered by
>> > modern agreements (as Jeff alludes to) has a clear paper trail, but
>> > there are the nonsensical cases like tape on the Hasselblad
magazines
>> > demonstrate how ludicrous things can become for reasons foreign to
>> > science and domestic to collectors willingness to pay. I take my
place
>>
>> > behind the line of those who have already pointed this out.
>> >
>> > Moon specimens that were incidental and innocuous gifts of
>> > questionable or no value at the time seem to have taken a special
>> > place. But, there are other exceptions as well. As I peruse the
aisles
>>
>> > of the gift shop at KSC I am tempted to buy a Space Shuttle heat
tile.
>>
>> > Yet NASA has allegedly gone on record saying that it will not
dispose
>> > of them by sale to the public (reason: we could be liable for
>> > unintended harm they might cause). Rumor has it that the Soviet
Buran
>> > tiles are more interesting to collect and Russia has no such hang
ups
>> > over them, so I'll hold out for one of them. If I had an American
one
>> > it would not be satisfying in present company. I couldn't freely
share
>>
>> > it with my international friends without risking being thrown in
jail
>> > for providing sensitive military secrets to other nations... at
least
>> > that is the rumor on how it was for a long time ...
>> >
>> > There is a clear demonstration of double standard and a
willingness to
>>
>> > invent retroactive laws, which should be prohibited
constitutionally,
>> > but the American system separates the judicial and that makes
>> > legislation from the bench a convenient option in cases like this.
How
>>
>> > frustrating for Mr. Rosen, the guy who bought the gifted moon rock
>> > from a Honduran official for a large sum of money. The government
>> > simply snatched it from him and it was not because the Hondurans
filed
>>
>> > a claim. If he had been compensated for his recovery of the
specimen
>> > it would be different in my view. But the way it went down, there
is
>> > reason to be wary of the court's freeloading and arbitrary mindset
in
>> > these cases. It is quite removed from science and boils down to
>> > politics and setting cruel and unusual precedents at the expense of
>> > citizens for prior shoddy control practices. Mr. Rosen, the owner
at
>> > the time of the Moon rock was never charged with any criminal
activity
>> > - they just took the rock plaque and left him to brood. If they
could
>> > have charged him I sort of think they would have given the zest to
>> > make examples out of people. But they got what they wanted - a
>> > precedent of no-ownership when before there was none to my
knowledge.
>> >
>> > I would point out that this nonsensical legal gymnastic that seems
to
>> > have developed ought to be applied to each and every scientist in
the
>> > United States that is on any payroll or grant for a project who
>> > supposedly buys specimens in his free time. How different is such
>> > piggybacking from the microgram residues on a piece of tape out of
a
>> > camera? How did Dr. King amass that huge personal collection on
many
>> > field trips to places such as, aw, forget it. Not worth going
into, it
>>
>> > would be more counterproductive than good to go there.
>> >
>> > Best wishes
>> > Doug
>> >
>> >
>> >
>> >
>> >
>> > -----Original Message-----
>> > From: Jeff Grossman <jngrossman at gmail.com>
>> > To: meteorite-list at meteoritecentral.com
>> > Sent: Sat, Jun 25, 2011 8:34 pm
>> > Subject: Re: [meteorite-list] Moon Dust
>> >
>> >
>> > What law are you talking about?
>> >
>> > On 6/25/2011 7:55 PM, Michael Gilmer wrote:
>> >> Hi Jeff and List,
>> >>
>> >> What strikes me here is that NASA has 842 pounds of lunar material
>> > and
>> >> they are apparently bent out shape over a few milligrams of dust
>> >> clinging to a piece of scotch tape. It's absolutely silly and it
>> >> speaks of skewed priorities.
>> >>
>> >> It was mentioned to me in private email by a respected list member
>> >> that the NASA samples in question were not addressed by the law
until
>>
>> >> 1972. If that is true, then it seems to me that any sample removed
>> >> legally prior to that date would be "grand-fathered in" as legal.
>> >>
>> >> A relevant example would be trinitite. Trinitite removed before
the
>> >> law specifically addressed it is legal. However, going to the site
>> >> now and removing trinitite is illegal. Another example would be
>> >> Canyon Diablo iron meteorites - those CD meteorites removed before
>> > the
>> >> "prohibition" are legal. Those removed today are illegal because
one
>> >> must trespass to get them. The devil is in the details - how does
one
>>
>> >> distinguish a legal Diablo meteorite from an illegal one? And how
>> >> would one determine a legal piece of dusty tape from an illegal
one?
>> >>
>> >> ATTENTION GOVERNMENT - STOP PISSING AWAY OUR TAX MONEY CHASING
AFTER
>> >> DUSTY TAPE! Instead, here are some suggestions for using our tax
>> >> money - build homes for the homeless, feed the hungry, offer
medical
>> >> care to the sick, create jobs for the unemployed, fund the
sciences,
>> >> or any number of things that are more important than dusty tape.
>> >>
>> >> Best regards,
>> >>
>> >> MikeG
>> >>
>> >
>> > ______________________________________________
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Received on Mon 27 Jun 2011 12:57:26 PM PDT