Freezing rain: What do the airline pilots do?

"Peter R." writes:
Christopher Brian Colohan wrote:

first, it means that the planes
will fly through the freezing levels quickly (and up higher where it
is too cold for ice accumulation), so they don't pick up much ice.

Thanks, Chris. Regarding the above, that may be true for departing
aircraft, but what about aircraft on approach to a busy airport? It is
certainly probable that these aircraft may be vectored around at lower
altitudes for many minutes at slower speeds. I would imagine that if this
occurs in heavy freezing rain this could be a real problem, no?

(speaking from a complete lack of experience...) I also imagine that
this could be a problem, and I would guess that the solution is "don't
do that". If a plane is picking up ice, the solution is to leave the
icing conditions -- either climb or descend. I'm sure ATC would allow
a plane to do this if a request was made.

Chris

On the ground, freezing rain does to an airplane just what
it does to your car. The entire airplane is clobbered.
Doors won't open or close properly. Flaps, ailerons and
spoilers may be frozen in position.

Before take-off, airlines spray boiling hot water on the
airplane (180° or so) to remove the snow and ice, then they
switch to a heated mixture of water and anti-freeze to keep
any ice from accumulating on the airplane during the time it
takes to taxi and take-off. As rain/snow fall on the plane
and melt, the antifreeze solution become diluted and the
water will begin to freeze in hinges and such.

The FAA parts 121 and 135 do not allow take-off in certain
extreme icing conditions, but pilots have the authority to
NOT GO even when the regulation might allow.

In-flight, the aircraft anti-and de-icing systems will
handle typical icing encounters, but severe icing is defined
as ice that build TOO FAST for even the equipment to handle.

see
http://ecfr.gpoaccess.gov/cgi/t/text...1.21&idno= 14
and
http://ecfr.gpoaccess.gov/cgi/t/text...1.14&idno=1 4



"Christopher Brian Colohan" wrote in
message .. .
| "Peter R." writes:
| Christopher Brian Colohan wrote:
|
| first, it means that the planes
| will fly through the freezing levels quickly (and up
higher where it
| is too cold for ice accumulation), so they don't pick
up much ice.
|
| Thanks, Chris. Regarding the above, that may be true
for departing
| aircraft, but what about aircraft on approach to a busy
airport? It is
| certainly probable that these aircraft may be vectored
around at lower
| altitudes for many minutes at slower speeds. I would
imagine that if this
| occurs in heavy freezing rain this could be a real
problem, no?
|
| (speaking from a complete lack of experience...) I also
imagine that
| this could be a problem, and I would guess that the
solution is "don't
| do that". If a plane is picking up ice, the solution is
to leave the
| icing conditions -- either climb or descend. I'm sure ATC
would allow
| a plane to do this if a request was made.
|
| Chris

Jim Macklin wrote: brevity snip

Before take-off, airlines spray boiling hot water on the
airplane (180° or so) to remove the snow and ice, then they
switch to a heated mixture of water and anti-freeze to keep
any ice from accumulating on the airplane during the time it
takes to taxi and take-off. As rain/snow fall on the plane
and melt, the antifreeze solution become diluted and the
water will begin to freeze in hinges and such.

Light frost on the aircraft prompted our pilot in SLC to de-ice.
One plane ahead of us: total delay ~45 minutes.

http://i16.tinypic.com/4gr9p8n.jpg
http://i10.tinypic.com/2rcu9sh.jpg
-----

- gpsman

SLC and frost, who would have thunk it?

Frost can be polished smooth, but a gallon or two of alcohol
spray does a good job on light aircraft as long as there is
no precip falling and the sun is out. Airports stock
alcohol for windshield and prop deicing on aircraft. Don't
use the stuff they sell at the auto stores for car
windshields, it will probably damage the plastic windows on
your plane.

The best cure,aside from a trip to Florida, is a heated
hanger. Roll the plane in under the IR heaters, and
pre-flight while the frost disappears. Cold weather
pre-flights are often rushed and incomplete because of the
cold.

If you have to do it outside in -20 wind-chill, dress
properly, hypothermia can make the take-off dangerous since
your mind won't be work at 100%.




"gpsman" wrote in message
oups.com...

Jim Macklin wrote: brevity snip

Before take-off, airlines spray boiling hot water on the
airplane (180° or so) to remove the snow and ice, then
they
switch to a heated mixture of water and anti-freeze to
keep
any ice from accumulating on the airplane during the time
it
takes to taxi and take-off. As rain/snow fall on the
plane
and melt, the antifreeze solution become diluted and the
water will begin to freeze in hinges and such.

Light frost on the aircraft prompted our pilot in SLC to
de-ice.
One plane ahead of us: total delay ~45 minutes.

http://i16.tinypic.com/4gr9p8n.jpg
http://i10.tinypic.com/2rcu9sh.jpg
-----

- gpsman

Jim Macklin wrote:

The FAA parts 121 and 135 do not allow take-off in certain
extreme icing conditions, but pilots have the authority to
NOT GO even when the regulation might allow.

The Canadian MOT doesn't allow takeoff with any ice. Some, however,
have forgotten that:

http://aviation-safety.net/database/...0117-0&lang=en

FAA requires ice removal for all take-offs, but depending on
what the weather conditions are, take-off may or may not be
allowed. Light snow, drizzle can be controlled by
application of anti-icing fluids after de-icing. But heavy
rain, whether freezing or not will wash the anti-icing
fluids away and allow to form.


"cavedweller" wrote in message
oups.com...
|
| Jim Macklin wrote:
|
| The FAA parts 121 and 135 do not allow take-off in
certain
| extreme icing conditions, but pilots have the authority
to
| NOT GO even when the regulation might allow.
|
| The Canadian MOT doesn't allow takeoff with any ice.
Some, however,
| have forgotten that:
|
|
http://aviation-safety.net/database/...0117-0&lang=en
|

Jim Macklin wrote:
FAA requires ice removal for all take-offs,

The Pelee accident came to mind because of the similarity with recent
weather in the Detroit/Windsor area with the condtions at the time of
that accident in 2004 and the almost matching dates.