h a l f b a k e r yWe have a low common denominator: 2
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Salty wing
Sodium Chloride spray for aircraft wings | |
This would be a solution of thick brine and a temporary
fixative. One would spray it onto the wing before flight to
help prevent wing icing.
Edit: If you're worried
about corrosion
just mix zinc with the salt.
Salt corrodes naked Aluminum
http://www.boatingm...alt-water-corrosion
Aluminum can seemingly dissolve away in salt water when in the presence of other metals. [popbottle, Dec 20 2013]
Generally Recognized as Safe ?
http://en.wikipedia...ki/Propylene_glycol
Would you drink Propylene_glycol on a dare? Nor would I. [popbottle, Dec 20 2013]
Cicadas make "pan" calls
http://biology.clc....ncarter/recipes.htm
just short of a mayday [lurch, Dec 23 2013]
Irrefutable proof
http://t2.gstatic.c...2NHpPGTv4d07XCfrLUw
" … a bowl of petunias, and a rather surprised-looking whale …" [8th of 7, Dec 26 2013]
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Annotation:
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See Link. Your wings never have any ice, but one day they just fall off the plane ? |
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There are many alternative solutions already being sprayed for this purpose. Chlorides and Aluminum/Aluminium = Bad News. |
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What everyone else said. [-] |
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I just spent some time looking up some properties of
"aluminum chloride". When dissolved in water the
freezing point of the water is lowered (much like is
true with ordinary salt-water). Since the chlorides
here are already attached to aluminum, perhaps they
won't eat the metal? |
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Yes, it will. The anion doesn't matter, it's the
chloride cation in solution that does the
damage. |
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It's true, and it's sad, because the chemical cocktail that is
used to de-ice the aluminium skin of airplanes (highly
diluted propylene glycol with a "handful of additives", as I
once heard it described by an Air Force spokesperson) is
slightly nasty shit
that runs off the tarmac into streams and ground water, or
even worse leeches into aquifers and ends up in the
drinking water of the low-income neighborhoods you find
around airports. |
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//leeches into aquifers // that's the last thing you
want - those fuckers'll eat you alive given the
chance. |
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//One would spray it onto the wing before flight to
help prevent wing icing.// |
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How would this help? At 500mph, how much is going
to stay on the wing? And of that which does, how
much is going to be there after flying through a
cloud? |
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//Would you drink Propylene_glycol on a dare? Nor
would I.// |
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//The anion doesn't matter, it's the chloride cation
in solution that does the damage.// |
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The cation does matter to some extent. If it's a metal
less electropositive than aluminium (e.g. copper) the
corrosion will be faster; if it's mercury you're
screwed. |
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Correct. The initial explanation was
deliberately simplified; introducing a table of
electrode potentials would not necessarily be
helpful for those who do not understand
electrochemical processes, and unnecessary
for those that do. |
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I propose that a sugar solution be used. It will
lower freezing point of water like any solute. It will
stay on the wings because its hella sticky and also
bright pink. If it leeches into aquifers the tiny
critters there will burst into hyperactive
rejoicingment. |
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// just mix zinc with the salt // may be a little unwise- It's lower in the electrochemical series than is aluminium. |
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Beef dripping, as fat seems to insulate whales. |
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Elephant dripping - suitable for jumbo jets ? |
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//Would you drink Propylene_glycol on a dare?// |
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On a dare, no. On a bet? Probably yes. How much
glycol and how much money? |
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Remember, everything's toxic in sufficient
quantities, but the quantities for PG are fairly high. |
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Hey, I'm first in line, [MechE] - see above. |
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Also, isn't the antidote for the resulting formaldehyde or whatever poisoning, ethanol? OR is that ethylene glycol, not propylene glycol. |
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I dunno, better drink some ethanol just in case. |
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Incidentally, a team in Oslo may have just made
this redundant. They were looking at migratory
cicadas, which travel in huge numbers from
Norway to southern Spain. In so doing, they have
to cross at least one mountain range; they also
maintain a high altitude to avoid predation by
birds. |
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This means that they are routinely exposed to
conditions in which aircraft wings would be at risk
of icing, yet the cicadas never ice up. |
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The Oslo team built several camera-equipped
drones which flew alongside the cicadas, recording
high-resolution, high-speed video. It turns out
that ice does
begin to form on the cicada's wings, but their
surface texture is such that they repel ice better
than any known material. The growing ice crystals
therefore just slip off before they can get large
enough to impede flight. |
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They are now working on a paint which will mimic
this texture, to prevent icing on aircraft wings.
(And yes, they lost three of their drones due to
icing.) |
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//cicadas never ice up// The fact that one never
hears cicadas calling in a mayday to air traffic control
should not, I think, be considered definitive. |
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Absence of evidence does not constitute evidence of absence. |
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Maybe they do call, but their chirps are mistaken for static, or interference ? |
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Perhaps they just make "pan" calls, knowing that even if the stall, they can easily just land and wait for the ice to melt. |
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I saw that, but you said yes to a dare. I'm the one
who saw how to monetize the opportunity. |
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[8th] In conditions where the drones were heavily
iced, the cicadas were iceless - they didn't observe
any icelessnessless cicadas. |
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//In conditions where the drones were heavily iced |
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Not too much marzipan please. |
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//They are now working on a paint which will mimic this texture// |
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Currently, this product/texture has bugs in it. |
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Ah - I'd heard it was a slug of magnesium. |
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//Typically its a magnesium coated goat bolted to the
outside of the structure. |
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Put a magnesium coated baby goat on each wing, for
redundancy, just kid-ding. |
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Anyway, my money is still on blubber*. I mean when did
you last hear of a whale icing over at 35,000 ft? |
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*Which does sound unhygenic, thinking about it. |
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// when did you last hear of a whale icing
over at 35,000 ft? // |
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Just after the Heart of Gold arrived in orbit
around Magrathea, with Zaphod, Trillian,
Ford and Arthur on board. |
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There is no record of the bowl of petunias
icing up though, which suggests a further
avenue of enquiry. |
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Purely apocryphal...show me the photos and I might
believe. |
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Bun for falling whales and cicada recipes. |
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Er, that's a painting. Until you can at least produce the
original sketch, I'm sticking to my guns. |
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Of course, nobody guessed that it falling whales from
Area 52 that brought down the twin towers, all that plane
malarkey was just the cover up.... |
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It's not even a very good painting. A sperm whale is
about, what, 50ft long? In which case the bowl of
petunias is about 3ft in diameter, which is
improbable. |
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// the bowl of petunias is about 3ft in
diameter, which is improbable // |
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Oh wonderful, another conspiracy theorist.
Why can't you just accept that a bowl of
petunias can be "quite big" ? Yes, yes, Elvis is
dead, the moon landings really happened, the
twin towers were brought down by aircraft
hijacked by arab terrorists … what next -
there ain't no Sanity Clause ? |
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Petunias display what is known as "quorum sensing
root inhibition". This means that, if a plant grows
beyond a certain (quite small) size, the roots start
to produce a compound which inhibits other plants,
and also the petunia itself. The purpose is to create
a clear patch around the plant. (The parent plant
sends out runners, which may root outside this zone
of inhibition). |
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Thus, a 3ft bowl of petunias is unlikely. |
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You'll be claiming there were no petunias
growing on the Grassy Knoll next … |
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There may have been, but only in small clumps. Had
the clumps been of unlimited size, it would have
been the petuniaey knoll, wouldn't it? |
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And technically it wasn't a knoll. |
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Oh god, next it's going to be the Four Mile Island accident conspiracy theory all over again. |
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Hmm, give the Borg his dues, most oil paintings have yet to be retro-fitted with the disclaimer "Objects depicted on this canvas may be smaller than they appear". |
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The bowl might be only 2ft across due to optical distortion in the canvas. Possibly if we knew the curvature of the threads, a more accurate estimate might be derived? |
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Have none of you taken an oil painting class? The
orientation and concentration of the source lighting makes
it obvious that the bowl of petunias is a foreground object,
while the sperm whale is quite a bit further back. Without
a horizon or a third, fixed object, it is quite impossible to
determine the exact positions of the objects, but
comparing the petunia blossoms to the width of the bowl
I'm putting the bowl's diameter at no less than 18" and no
more than 26". |
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I have. My tutor made one overarching impression
on me - if he said it once, he said it a thousand
times: "Bowls of petunias are always placed at the
same distance as whales in compositions." |
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M'lud, was your tutor by any chance a Russian exile
named Pyotr who wore a beige eyepatch and was half-mad
from ingesting the lead in the dentures made for him by
the one-handed orthodontist at the Rayskiyotdykh Gulag? |
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Good lord! You knew Monocular Pyotr?! His
methods were unconventional, as you know, but
then so was his capacity for Tia Maria. |
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He tought me for, oh, about six or seven years. It
was only at the end of that period that I
discovered he was blind in his right eye, which (in
retrospect) makes it odd that he wore the patch
on his left one. |
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He never talked about his time in the Gulag,
except when he was awake. He had fond
memories of a beverage/brush-cleaner which they
used to make by fermenting and distilling pine
needles. |
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I wonder what old Pyotr is up to now. Probably a
couple of litres a day, if I extrapolate. |
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You may be glad to learn that our mutual friend is currently
enjoying a faculty position here at the Heathen Institute
for Inadvisably Applied Science & Chronological
Malfeasance as our Professor Emeritus of Classical Art
Misinterpretation. His daily intake has indeed increased,
and his fondness for sampling questionable substances left
in
open containers has led to him spending a lot of time in the
east wing of the Fowler Building. |
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Glad Pyotr has landed on his feet (though I expect
he'll rectify that situation soon). |
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Next time you trip over him, please pass on my best
wishes and remind him that he still has my third
under-pantrymaid. |
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Yes, he keeps her in a jar in his office. |
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Oh dear. Oh very very dear. |
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