FAR 91.157 Operating in icing conditions

Ron Natalie wrote:
"Matthew S. Whiting" wrote in message ...

It's illegal for him to operate IFR period.

Really? Even if you don't fly in the clouds?


If he is in a case where that reg applies to him, yes. The rules don't
say "in clouds" they say Instrument Flight Rules.



If the forecast icing isn't all the way to the ground, why isn't it
legal to file and fly below the clouds and the altitudes with forecast
or known icing?


Matt

We have an *authorized procedure* out here in the Pacific Northwest,
developed by the FSDO Aviation Safety Manager and the folks at the TRACON,
specifically for use when icing conditions are forecast. It is called "Radar
Vectors for Ice" and involves vectors to climb away from the Cascades until
high enough to be well above the freezing level or in the clear. Obviously,
since this procedure was developed by the FAA and published in the Safety
Program newsletter every year at this time, a forecast of icing conditions
is not, in and of itself, a bar to flight.

There is a CYA caveat, of course, that nothing in the procedure should be
taken as encouragment to take off into icing conditions.

Bob Gardner

"Teacherjh" wrote in message
...

For us little guys, ANY ICE AT ALL is forbidden. (unless the aircraft
is
certified for known ice, which very few spam cans are).


Forbidden by what?


The laws of physics, ultimately. The FARs before that (though I can't
find a
specific rule, it would certainly be classified as "careless and reckless"
if
it led to an incident - it might be in the certification rules for
aircraft,
same as aerobatic stuff and equipment required.) The FAA has made it
clear
that unless the aircraft is certificated for known ice, you can't even
legally
enter forecast ice.

Now, to open another can of worms, the FAA has produced an excellent video
on
icing (which they show at various safety seminars) in which they take the
viewer through several flight scenarios. Well worth watching several
times.

However, I take a bit of an issue with one thing - the "unprotected"
(non-de-iced) airplane pilot is flying in the clouds in non-icing
conditions,
towards a front that contains ice (there is ice above). On takeoff the
weather
briefing indicated that the front would not be an issue, but the weather
moved
in faster. Temperatures go down, and he gets ice. Now what?

IN subsequent discussion, one possibility is to climb and get on top of
the
overcast, and it would be reasonable if the destination were clear.
(mabye
also in other situations). This would be legal (he's already in ice and
trying
to get out). However, if he were not YET in ice, it would be illegal
(deliberately entering icing conditions). Seems to me that at that point,
(he's in non-icing conditions, non-icing is behind him, temps going down ,
his
destination ahead of him, and ice ahead of him) continuing would be
illegal,
but the FAA guy didn't have the opinion that continuing would constitute
"deliberately entering ice..." and it's all a matter of bablance.

Well, yes but...

Jose

--
(for Email, make the obvious changes in my address)

Bob Gardner wrote:

We have an *authorized procedure* out here in the Pacific Northwest,
developed by the FSDO Aviation Safety Manager and the folks at the TRACON,
specifically for use when icing conditions are forecast. It is called "Radar
Vectors for Ice" and involves vectors to climb away from the Cascades until
high enough to be well above the freezing level or in the clear. Obviously,
since this procedure was developed by the FAA and published in the Safety
Program newsletter every year at this time, a forecast of icing conditions
is not, in and of itself, a bar to flight.

Of course not -- airspace is three-dimensional. I don't cancel a flight
planned for 4000 ft in the summer because there's icing forecast from 15,000
to 20,000 ft. I wonder if there is anyone in this group who is seriously
arguing that I should cancel such a flight.


All the best,


David

"Matthew S. Whiting" wrote in message ...


If the forecast icing isn't all the way to the ground, why isn't it
legal to file and fly below the clouds and the altitudes with forecast
or known icing?

Don't ask me, I didn't write the regulation. Presumably because they have not
put in procedures into the IFR rules to handle, IFR but remain clear of IMC.
They presume that if you are operating IFR you are prepared to enter IMC at any
time.

Obviously, since this procedure was developed by the FAA and
published in the Safety Program newsletter every year at this time, a
forecast of icing conditions is not, in and of itself, a bar to
flight.


Hmmmm...You're saying that the Safety Program newsletter trumps the
FARs?

I believe you're referring to FAR 91.13, which is Careless OR Reckless
Operation, not careless AND reckless. I own the aircraft and fly it solo,
how does flying it into known icing conditions endanger the life or property
of another?


You are right - careless OR reckless. No matter. It's not legal. It's
usually not smart.

If you have an aircraft that is not certificated for flight into known icing
(say, a typical spam can), even if it is older than the regs, doing so puts it
at the very real risk of acquiring ice on the airframe. An iced up airplane
does not fly very well. It is less stable, has less lift, more drag, less
power (as the prop and intake get iced), and more weight. Your instruments will
be less reliable, and may fail (i.e. the static port gets iced) If the tail
ices up faster than the wing, you can get into a tail stall, which feels simlar
to a wing stall but whose recovery is the opposite.

What's more, unlike say for turbulence, cloud, or an unusual attitude, exiting
the icing conditions does not fix things. The ice that you have picked up
doesn't just "go away" right away, especially if it's still cold out.
Sublimation is very slow, and you have to get into fairly warm temps to melt
the stuff. You can't count on that.

One of the big problems occurs on landing iced up... the trim (if it still
works) and configuration changes may destabilize the aircraft even if it seemed
to be flying "just fine" before.

Further, once you're in it, you might not be able to get out. It might be that
conditions are closing all over. So, you might not end up with "just a peek"
but rather, a whole lot of dunk.

Certification for known ice includes more than just boots. There's a whole lot
of redundancy involved, and significant excess power needed in the powerplant
to overcome the effects of ice.

This is part of the reason why it's not safe. It endangers people and property
below you, far more than simply flying. Because of this, the FAA would
consider it careless. It would also consider it reckless. The FAA has already
said that "forecast" icing conditions count as "known" icing conditions, even
in the face of pireps to the contrary.

Jose

--
(for Email, make the obvious changes in my address)

It's illegal for him to operate IFR period.

Really? Even if you don't fly in the clouds?

If he is in a case where that reg applies to him, yes. The rules don't
say "in clouds" they say Instrument Flight Rules.

I think that all the icing forecasts I've seen say ICGICIP (icing in clouds
and in precipitation), so if you stay out of the clouds and precip there's no
forecast icing.

Barry

There is not one word in Part 91 relating to "known icing" other than
91.527, which applies to large and turboprop aircraft. The closest you can
come is 91.9, so there is nothing to "trump" because the POH wording is not
consistent between manufacturers or models (and, as some have pointed out,
some POHs say nothing about icing).

The west slopes of the Cascades are notorious for icing..the Concorde was
sent out here for icing certification. If you can climb (or descend) over
the flatlands to the west of Seattle, you can miss the icing zone. The
newsletter simply tells pilots that when ATC turns them east on departure,
cleared to some altitude that will take them into the ice, they do not have
to accept the clearance...nor need they descend into the clouds on the west
side simply because a controller clears them to a lower altitude.

Bob Gardner

"Greg Esres" wrote in message
...
Obviously, since this procedure was developed by the FAA and
published in the Safety Program newsletter every year at this time, a
forecast of icing conditions is not, in and of itself, a bar to
flight.


Hmmmm...You're saying that the Safety Program newsletter trumps the
FARs?

"Steven P. McNicoll" wrote in message
.net...

"Teacherjh" wrote in message
...

This applies to large and turbine powered aircraft.

For us little guys, ANY ICE AT ALL is forbidden. (unless the aircraft
is
certified for known ice, which very few spam cans are).


Forbidden by what?

The closest you can come is 91.9, so there is nothing to "trump"
because the POH wording is not consistent between manufacturers or
models (and, as some have pointed out, some POHs say nothing about
icing).

But some do, and the wording inconsistency doesn't seem relevent when
the meaning is clear. My Seneca says "Not approved for known icing",
and I don't think that ATC procedures can therefore make it legal.

And there is always 91.13 (Careless or Reckless) for the FAA to fall
back on.