FIKI

youngflyer

Well-Known Member
Just trying to understand the FAA's definition of flight of know icing for my checkride. My understanding is that the FAA does not specify anything governing part 91 flights in the FAR/AIM, but has released interpretations basically saying that if there are clouds forecasting along your route and at your filed altitude, the temperature is forecast to be below freezing, and you fly anyway, you are subject to enforcement? This is assuming a non FIKI equipped aircraft. Could someone validate this or correct me?
 
Just trying to understand the FAA's definition of flight of know icing for my checkride. My understanding is that the FAA does not specify anything governing part 91 flights in the FAR/AIM, but has released interpretations basically saying that if there are clouds forecasting along your route and at your filed altitude, the temperature is forecast to be below freezing, and you fly anyway, you are subject to enforcement? This is assuming a non FIKI equipped aircraft. Could someone validate this or correct me?

Good luck, there's one interpretation, but its not a very good one in my opinion. The feds really really really need to come up with a definition, the current ambiguity is dangerous in my opinion.
 
In a recent LOI, the FAA has acknowledged that it takes more than just visible moisture and freezing temperatures to make "known icing." Beyond that, they have not set a formal definition, nor does it seem they ever will.

The current philosophy says that it is the pilot's discretion as to what is "known icing," which makes sense because without an accident, it's almost impossible for the FAA to actually enforce any of it (which would explain why there is no reg about it). Bands of the right size supercooled droplets to produce icing are marginally predictable at best. The newest NOAA tools (CIP, FIP) combined with infrared satellite imagery, and any Airmets should, in most cases, enable you to make a reliable go or no go decision.

I would assume that in cases of blatant or obvious disregard, you'd get slapped with "careless and reckless."

Now to dig up that LOI...
 
http://download.aopa.org/epilot/2009/090126icing.pdf

Apparently, I was off by a bit. Known icing is when you look at your wing and there's ice on it. The letter, however, goes on to say what I did in my first post.

The feds really really really need to come up with a definition, the current ambiguity is dangerous in my opinion.

Like I said, not so sure man. Icing is too ambiguous to regulate, as the LOI discusses.

I compare it (with students) to FM radio static. If you're driving through mountains or tunnels, you'll probably get some. Where and when exactly, nobody is sure, it depends on a few things. How long it will last, again, no concrete clues. Will we still hear New Kids on the Block, or will it be all static? Tough to tell. How can we get out of it? Go to where we know it can't be. Where is that? Etc, etc...
 
The confusion with known icing being, "flight into visible moisture below freezing," is due to an old definition. Sometime in 2005 if I remember correctly, this definition was released. I remember because it screwed up my flight experience in IFR winter conditions out of Nashua NH. That has recently been changed as previous posters mentioned.

I believe, but cannot quote a source, that known icing, aside from seeing it on your wing, is where it is reported to be. By this I am referring to pilot reports. Again, I am not sure if this is the case, but I am pretty sure I saw something like this in a previous AC.
 
I did some more digging. You can just disregard the previous post as I cannot verify all of the information. Instead, go to AC 91-74A on icing.

They define Known Icing as:

Known, Observed, or Detected Ice Accretion. Actual ice that is observed visually to be on the aircraft by the flight crew or identified by onboard sensors.

Do know that the term 'known ice' and 'known icing conditions are considered separate terms. An AOPA article on icing says this:

The letter to AOPA went on to say: “Most flight manuals and other related documents use the term ‘known icing conditions’ rather than ‘known ice,’ a similar concept that has a different regulatory effect. ‘Known ice’ involves the situation where ice formation is actually detected or observed. ‘Known icing conditions’ involve instead circumstances where a reasonable pilot would expect a substantial likelihood of ice formation on the aircraft based upon all information available to that pilot.”


Again in AC 91-74A the FAA talks about planning your flight with regards to icing conditions. You can find this near the bottom in Appendix 2 Page 2:

d. Aircraft Not Certificated for Flight in Icing Conditions.

(1) Aircraft certificated since the mid-1970s that are not certificated for flight in icing conditions will have a limitation in the AFM or POH and possibly a placard on the aircraft stating that flight into “known icing conditions” is prohibited. “Known icing conditions,” as defined in the AIM, are conditions in which ice is observed or detected in flight, by your aircraft or another aircraft, or an airport. Such limitations are binding under § 91.9, Civil aircraft flight manual, marking, and placard requirements, and this regulation takes precedence over §§ 91.527 and 135.227. However, if a pilot of such an airplane were to takeoff and fly in area in which icing is forecast (e.g., AIRMET Zulu), it is expected the pilot will through preflight planning and in-flight execution:

(a) First attempt to avoid areas of “potential icing conditions”, which are areas of visible moisture such as clouds at temperatures below freezing;

(b) Ifthatisnotpractical,attempttoavoidareasofforecasticingbyalltools available (e.g., AIRMETs, SIGMETs, CIP and FIP); and
immediately.

(c) If icing is encountered, declare an emergency and exit the conditions

NOTE: Failure to follow the section above may result in enforcement action under § 91.103, Preflight action, or § 91.13, Careless or reckless operation, depending on the circumstances and the actions a reasonable pilot will take. Pilot should remember, these airplanes were not tested for inadvertent encounters and since most icing conditions consist of small drops and low LWC, should not assume their airplane can tolerate all icing conditions after one successful encounter.

(2) Aircraft certificated prior to the mid-1970s that are not certificated for flight in icing conditions may not have any prohibitions stated in the AFM or POH. If not, they are not covered by either § 91.527 or § 91.9. However, given that information on the dangers of aircraft icing has been widely disseminated for many years, certain actions, such as taking off with wings coated with ice, could be interpreted as prohibited under § 91.13.
 
http://download.aopa.org/epilot/2009/090126icing.pdf

Apparently, I was off by a bit. Known icing is when you look at your wing and there's ice on it. The letter, however, goes on to say what I did in my first post.



Like I said, not so sure man. Icing is too ambiguous to regulate, as the LOI discusses.

I compare it (with students) to FM radio static. If you're driving through mountains or tunnels, you'll probably get some. Where and when exactly, nobody is sure, it depends on a few things. How long it will last, again, no concrete clues. Will we still hear New Kids on the Block, or will it be all static? Tough to tell. How can we get out of it? Go to where we know it can't be. Where is that? Etc, etc...


The whole "known icing" debate got turned on its ear with the FAA/AOPA exchange. The LOI is (deliberately) vague -- they give pilots enough slack in the rope to hang themselves. It seems that you have to have a plan IF you encounter it and be able to support it with facts (wx briefing data). I have no idea if this has been tested, yet.

Five things I always consider with icing: 1) Hearing a Baron getting vectored around asking for lower, and lower, and lower -- he just kept loading up; 2) This accident; 3) Picking up rime at -30C (10 below the bottom of the normal range -- "Well look at that..."); 4) Listening to a Mooney land at FULL power and, when it touched down, watching a thick sheet of clear ice slide off the airframe and shatter on the runway; 5) "Ice is not nice."

You just never know. Prior planning prevents pi$$ poor performance.

I have used this flight path tool in the past. It's good for finding an altitude and route for avoiding the icing area.
 
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