tail ballast antifreeze

If you have any metal parts in the piping, they won't appreciate the salt...

wrote in message
oups.com...

wrote:
I got this from our resident physicist and weather guru:

snip
From NHTSA on methanol in fuels:

"Methanol will attack and corrode certain metals, such as magnesium and
aluminum. Additionally, the corrosion products of aluminum and methanol
will precipitate out of the liquid fuel and clog filters and fuel
injectors. For this reason, it is recommended that metals such as
stainless steel and carbon steel be used in methanol fuel systems and
fuel delivery systems. Methanol will also attack many common
elastomeric materials, like rubber, polyurethane, and most plastics.
Elastomers with high fluorine content and Teflon have been proven to be
compatible with methanol."

... Ethanol is probably safer.
/snip

Thanks Mike!

~ted/2NO
"Jack Daniels for my V2C!"

Food graded PROPYLENE GLYCOL might be a good choice...it is less
effective then the ethylene glycol (very nasty stuff)...15% solution is
good down to 10 deg. F.I just don't know if it will react with
fiberglass....propylene glycol is used in cosmetics, food processing,
hospitals, etc. But also keep in mind that adding a kitchen salt into
fresh water will bring the freezing point down....my 2 cents....

wrote in message
oups.com...
I'm betting there is a really good reason, but why not use automotive
antifreeze? Is it not compatible with composites?

Very bad for the environment.


and you can't drink it if you land out.

Al

Try windshield washer fluid

Does anyone disagree with JS's statement that I do not need tail
ballast antifreeze for flying at -5C for six or seven hours? I can't
imagine six liters of sloshing water freezing at only a few degrees
below. But I don't have practical experience in this area and I don't
want to make a really expensive mistake.

I appreciate all the feedback but I'm specifically asking about (1)
methanol, (2) ethanol and (3) none. I'm familiar with all the other
options from older posts.

Ely in 3 days -- can't wait!

~ted
V2C "2NO"

wrote:
Does anyone disagree with JS's statement that I do not need tail
ballast antifreeze for flying at -5C for six or seven hours? I can't
imagine six liters of sloshing water freezing at only a few degrees
below. But I don't have practical experience in this area and I don't
want to make a really expensive mistake.

I appreciate all the feedback but I'm specifically asking about (1)
methanol, (2) ethanol and (3) none. I'm familiar with all the other
options from older posts.

Ely in 3 days -- can't wait!

I've been flying out of Truckee, Minden, Tonopah, Ely, and Parowan for
15 summers or so, and have numerous ballasted 5+ hour flights in the 15
to 18K foot range. I have never used antifreeze, and never had the tail
ballast freeze. I have never noticed anyone else using antifreeze
during the summer at these sites...

Marc

The German manufacturers would rather have their customers release the =
tail ballast at +2=BAC. I suspect solar radiation is the reason why =
people can keep their water at lower air temperatures without =
immediately being awarded a split tailplane.
So if you have both outside temperatures below 2=BAC and no sunlight ... =
beware!

Francisco De Almeida wrote:
The German manufacturers would rather have their customers release the =
tail ballast at +2=BAC. I suspect solar radiation is the reason why =
people can keep their water at lower air temperatures without =
immediately being awarded a split tailplane.
So if you have both outside temperatures below 2=BAC and no sunlight ... =
beware!

I've been assuming that solar heating is the reason that the tail
ballast doesn't end up freezing during these summer flights. At a few
degrees below 0C in shadow, it should still take something more than an
hour for a few liters of water to freeze to the extent that it would
cause structural damage. Lack of lift and cold toes would cause me to
seek warmer environs long before that point...

I may as well mention another variable: radiant temperature.

Imagine you are attending a spring wave camp in some Nordic country. It =
is a beautiful, cold, clear day without a trace of cloud. The sun gives =
little warmth as its rays are so slanted. In these conditions, even if =
outside air temperature is, let's say, +2=BAC, you are already in risk, =
because the sky vault has a radiant temperature some ten degrees lower =
than the local air temperature, and will be chilling all exposed =
surfaces. This is the same mechanism that causes frost on clear nights. =
Manufacturers have to take into account such worst case scenarios for =
certification purposes.

In a midsummer Arizona day things will be quite different. The blazing =
sun, re-irradiation from cumulus clouds and even from the warm ground, =
will ensure that the mean radiant temperature to which the glider is =
subjected is higher than the air temperature at altitude. Therefore, a =
(few) degrees below zero will still be safe.

Wont the "sloshing around" restrict the ability of the water to freeze solid? More likely to get a frozen slushy effect.
I suggest vodka 20% and red cordial at 20% would be the perfect mix, wont freeze solid, you can see it on the metal bits to hose it off and it wont bother the feilds too much when dumped. Cant wait for first drinks at an outlanding party either!

Bagger








HEY! Only joking!

Francisco De Almeida a écrit :
I may as well mention another variable: radiant temperature.

Imagine you are attending a spring wave camp in some Nordic country. It =
is a beautiful, cold, clear day without a trace of cloud. The sun gives =
little warmth as its rays are so slanted. In these conditions, even if =
outside air temperature is, let's say, +2=BAC, you are already in risk, =
because the sky vault has a radiant temperature some ten degrees lower =
than the local air temperature, and will be chilling all exposed =
surfaces. This is the same mechanism that causes frost on clear nights. =
Manufacturers have to take into account such worst case scenarios for =
certification purposes.

In a midsummer Arizona day things will be quite different. The blazing =
sun, re-irradiation from cumulus clouds and even from the warm ground, =
will ensure that the mean radiant temperature to which the glider is =
subjected is higher than the air temperature at altitude. Therefore, a =
(few) degrees below zero will still be safe.

you're right, but I suspect that thermal inertia is even more important
than radiation. Put 5 liter of water at 30°C in an fiberglass can into a
freezer at -5°C, I suspect it will take hours to freeze. And in flight
you're not always at cloudbase, only the temperature at mean altitude counts

--
Denis

R. Parce que ça rompt le cours normal de la conversation !!!
Q. Pourquoi ne faut-il pas répondre au-dessus de la question ?