1800 Gallons of De-icing fluid...

"Montblack" wrote

Wow, $2.2 million ....@ $11/gallon.

Hmm? Large folding 'portable hangar' vehicle. Maybe two.

I wonder if anyone has ever considered a rig that has a series of jet
engines (about a dozen -maximum- ought to do it) that come in around the
plane and shoot their hot exhausts on the wings and the rest of the plane,
and heat the ice up to melt it away?

It could be regulated, temperature wise, by using a venture effect to draw
cool air in to the stream. I would think that a few minutes ought to melt
the whole thing, and be ready for the next one in a few more minutes. You
would not have to melt all of the ice, since the alluminum should heat up
under the ice, then the fast hot air would blow the loose ice away! Hard to
melt portions could get a quick shot of afterburner, when necessary. g

The cost of run out engines would make it affordable, and the fuel should
not cost but a few hundred dollars per plane, and part of that offset by the
fact that the deicing fluid also costs money to heat up.

Shoot a little fluid onto it after it has melted off, to protect it against
the fresh ice still coming down, (when necessary) then off they go.

What do you all think? I'll bet NASCAR has some track dryers that we could
"borrow" to test the idea, then we go into production, and start
distributing them in time for next winter. Should make us millionaires, if
you want to partner up on the idea!
--
Jim in NC

I wonder if anyone has ever considered a rig that has a series of jet
engines (about a dozen -maximum- ought to do it) that come in around the
plane and shoot their hot exhausts on the wings and the rest of the plane,
and heat the ice up to melt it away?

Good idea.

Didn't the Air Force used to use jet engines alongside runways to clear
fog, back in the '60s?
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

"Mxsmanic" wrote in message
...
Jay Honeck writes:

And, since this isn't being done at a major airport (which would have
deicing stations to catch all that stuff), there is no recycling of
that fluid. It just goes away...all $3600+ worth of it.

What does deicing fluid contain?


Which manufacturer?

I wonder if anyone has ever considered a rig that has a series of jet
engines (about a dozen -maximum- ought to do it) that come in around the
plane and shoot their hot exhausts on the wings and the rest of the plane,
and heat the ice up to melt it away?

I'd say hot water is a more efficient way to heat the airplane, and
heating water is probably a more efficient use of fuel. The de-ice (I
think) is more to keep the ice off afterwards. The hot water does most
of the work.

Jose
--
He who laughs, lasts.
for Email, make the obvious change in the address.

Good idea.

I almost gotta ask, if it is such a good idea, why is it not being used?
There must be something wrong with the idea of a fundamental, or practical
level.

I wonder if the exhaust residue is the problem, being corrosive, or
something. I know the oil burned on older carriers was a problem for
aircraft corrosion, but they were in that stuff all of the time.

Didn't the Air Force used to use jet engines alongside runways to clear
fog, back in the '60s?

I think with limited success.
--
Jim in NC

In a previous article, "Morgans" said:
I wonder if anyone has ever considered a rig that has a series of jet
engines (about a dozen -maximum- ought to do it) that come in around the
plane and shoot their hot exhausts on the wings and the rest of the plane,
and heat the ice up to melt it away?

8 or 9 years ago there was a large structure on the commercial ramp at ROC
that was an experimental infared de-icing system - basically they pulled
it into this hangar and blasted radiant heat at it. It seemed like a
great idea to me, but evidently it was considered too slow or something
like that.

--
Paul Tomblin http://blog.xcski.com/
"SPARC" is "CRAPS" backwards --Rob Pike

Morgans wrote:
There must be something wrong with the idea of a fundamental, or
practical level.

One thing I can think of: Say you've got a jet engine sitting there on
the ground. You hook up a tank of Jet-A, put the throttle at idle, and
pull the starter rope. Once it starts, you open up the throttle a
little. What happens?

I'm not sure how much of a problem this would be, but there might be a
concern with the deicing jet engines sucking something up and causing
FOD to the aircraft being deiced.

I think that if you had your heart set on using warm air to deice a
plane, and you had a pile of Jet-A, your best bet would probably end up
looking like a big oil-fired forced-air furnace. It has an air-air heat
exchanger inside so only "clean" air (no combustion gases) get directed
at the aircraft. It needs a little electricity for the blowers and
maybe the ignition - no problem at a big airport, or for portable use,
put some of the Jet-A into a diesel engine-generator set.

The idea here is that a jet engine is designed to turn fuel into thrust,
and doing that creates some "waste" heat and noise. If all you're
really after is the heat, use a machine that's optimized for turning
fuel into heat.

Out of curiosity, I did a quick estimate of how much energy it might
take to de-ice a plane. http://www.airliners.net/info/stats.main?id=100
says that the wing area of a 747-400 is 541.2 m^2. I modeled the
fuselage as a simple cylinder of 5.5 m diameter by 68.6 m long, and
disregarded the tail entirely. I assumed that it has a quarter inch
(6 mm) of ice all over everything, and that the ice is at -10 C.

Ice on fuselage: 5.5 m * 3.14159 * 68.6 m * 0.006 m = 7.11 m^3
Ice on wings: 2 * 541.2 m^2 * 0.006 m = 6.49 m^3
Total ice: 7.11 m^3 + 6.49 m^3 = 13.6 m^3

1 m^3 is 1000 L and if those 1000 L are full of water, that's 1000 kg.
So we have 13600 kg or 30,000 lb (!) of ice.

According to the Bosch "Automotive Handbook", the specific heat of ice
is apparently 2.09 kJ/(kg * K), so to take those 13600 kg of ice from
-10 C to 0 C needs

13600 kg * 10 K * 2.09 kJ/(kg * K) = 284000 kJ = 284 MJ

The heat of fusion is 332 kJ/kg, so to melt the ice at 0 C into water at
0 C needs:

13600 kg * 332 kJ/kg = 4520000 kJ = 4520 MJ = 4.520 GJ (Great Scott!)

Total energy: 284 MJ + 4520 MJ = 4800 MJ

The specific calorific value of diesel fuel is 42.5 MJ/kg. (Other
common fuels are pretty close: regular gas 42.7, premium gas, avgas,
and kerosene 43.5.) So, if we could burn diesel fuel, recover 100%
of the energy in it, and put all that energy into melting ice, we'd
need

4800 MJ * 1 kg/42.5 MJ = 113 kg of diesel.

That's 113 kg * 1 L/0.835 kg = 135 L of diesel or

135 L * 1 gal/3.785 L = 35.7 gal of diesel.

At current Tulsa retail prices, that's about $81 worth.

Alternatively, we could get the heat from electricity:

4800 MJ * 1 kWh/3.6 MJ = 1330 kWh electricity

At eight cents a kWh, that's about $107 worth. Of course, this doesn't
take into account how the electricity was generated.

Matt Roberds

wrote in


That's 113 kg * 1 L/0.835 kg = 135 L of diesel or

135 L * 1 gal/3.785 L = 35.7 gal of diesel.

At current Tulsa retail prices, that's about $81 worth.

Sounds a lot cheaper than deicing fluid.

Jet engines are used as track dryers at race tracks, because they are a
ready made machine to burn a lot of fuel, and make a lot of heat and exhaust
velocity. Both are good for deicing.

I still think it is an idea that should be looked at more closely.

With several mounted on a rig, they could do a whole large jet in a few
minutes, compared to the many minutes now required, with little negative
impact to the ecology.
--
Jim in NC

"Jay Honeck" wrote in message oups.com...
: My A&P mechanic works a day job, in addition to doing small-plane
: maintenance. He is in charge of local maintenance on DC-9s that fly
: for a major freight hauler.
:
.............................
: If you ever wondered why it costs so much to ship a box of chocolates
: cross-country, now you know...
:
: ;-)
: --
: Jay Honeck
: Iowa City, IA
: Pathfinder N56993
: www.AlexisParkInn.com
: "Your Aviation Destination"
:

They were talking about installing one of these at Kalamazoo:
http://www.radiantenergycorp.com/dow...ekBrochure.pdf

More he
http://www.airporttech.tc.faa.gov/safety/infrared.asp
http://www.infra-red.com/icecat.php

http://www.infra-red.com/icecat.php

Neat idea. I wonder about how skilled the boom operator must be to
avoid smashing that thing into the aircraft, though.

I think that's one main advantage of deicing spray -- it doesn't take
any real skill to do it. This is always a good thing when you're
talking about an essentially undesirable job.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"