Malibuflyer wrote:
Flying through these clouds with an airplane that has the operational limitation not to fly through known and forecast ice is illegal. It might still be perfectly safe but is illegal. Therefore last Sunday you could not do any IFR in IMC flight legally with an airplane that has this operational limitation.
While from an operational and safety standpoint flying with an airplane which is not equipped for ice avoidance or removal into forecast icing of any level needs a lot of precautions and ways out, but I doubt it is actually illegal. Please re-read the applicable definition of known ice as quoted earlier here:
Known icing conditions are conditions where actual ice is observed visually to be on the aircraft by the pilot or identified by on-board sensors.
So neither what Adwice nor what your experience tells you actually is, legally, known ice. It becomes known only if it is actually observed to be on the airplane or is identified by on board sensors.
Everything else is forecast ice. I would add active pireps or reports to the known list, i.e. if your ATIS sais icing reported, I’d qualify that as known ice too. But not Adwice bulletins or anything else.
Otherwise, flying in IMC with non-fiki airplanes would be prohibited for all practical purposes, as icing is omnipresent in European weather throughout the year. Clearly, that is not the case. The main difference between non-fiki planes and others for the lack of a better definition is how long they can operate within ice.
Right here in my area, the main restriction in winter is low stratus, often only a few 100 feet thick. It hardly ever has much ice inside and lots of non-de iced or partially de-iced (hot prop) planes fly IFR through these layers regularly and they are the main reason the bother to do so. In other times, there are icing layers above or just at the cruise level but warmer air below, e.g. in summer, where flying with non-de iced or partially de-iced airplanes is also commonplace as long as there is a clear way out, in my view downwards mostly.
Where non-deiced or partially de-iced airplanes are not adequate is for flying in frontal conditions and there, quite a lot of fiki airplanes are not really adequate neither. In all such cases, evasive action is the most often done thing and rightly so.
As for Adwice, I recall talking to one of the original developers of this product. Green is light icing expected, Yellow is mod ice and Red is severe ice. They are not reports, they are model estimations, so clearly forecast. Light ice is something which according to the FAA definition most airplanes can handle for a short while. Moderate ice needs avoiding action and severe ice is a very bad idea, certified or not. It has occasionally brought down airliners.
So the main difference is how the different airframes can handle ice and how crews need to act on it. Turbo airplanes are clearly in the advantage when it comes to climb out of ice. Normally aspirated airplanes almost always need to avoid ice by descending. The big difference between airplanes with ice protection and those without is the amount of time they can spend to figure out the evasive action or even carry on, depending on the level of icing.
As a reminder:
To fuel the thread starter regarding priority of anti- and deicing means:
I would put prop de-ice way on front regarding capability and improvements.
Indeed, if goal is to “depart” then hot propeller with enough available power behind is good fit if the strategy is to climb then fly above if possible? or descend to fly under if not possible?
You may want to add “Electric propeller” vs “TKS propeller” 
I can tell you that prop TKS is extremely effective. I’ve had it since 2002. In the prop-only version, the 2-3 litre container would last a year or more.
The wing etc TKS is also extremely effective. The gotcha is you get ~1hr (a lot less on an SR22 going on full flow) which means it can’t be used for long enroute sections.
Hot props tend to be found on plates with rubber boots i.e. no TKS anywhere.
Mooney_Driver wrote:
Please re-read the applicable definition of known ice as quoted earlier here:
It has been discussed here before: The relevant operational limits in EASA AFMs are not only referring to “known ice” but to “known and forecast ice”. So if not all of the authors of AFMs (and the EASA as well) are stupid, there needs to be something like “forecast ice”.
In addition to that, with the definition of “known ice” you quote it is useless to talk about “flight into known ice” because you never can “know” according to your definition before you are in.
But let’s do a practical example: My IFR check ride last weekend. Perfectly fine weather with 5/8 clouds between 5000 and 7000ft. We started out through the clouds to FL80 picked up a bit of ice in the climb as expected, flew to destination and again in the descent again had some traces of ice.
Nothing to worry about and as my plane has operational limitation on ice nothing illegal.
We landed at the destination. On the way back we the very similar route and had to go through the very same layers of cloud.
Would you still argue, that this is not “known icing” as technically you can not know if in the same cloud 15 minutes later there is still ice? Really?
Mooney_Driver wrote:
Otherwise, flying in IMC with non-fiki airplanes would be prohibited for all practical purposes, as icing is omnipresent in European weather throughout the year.
That is simply not true: It is omnipresent in winter (and yes, it is exactly my point that therefore you rarely can legally fly IMC in winter with an airplane that is limited to “no flight into known and forecast ice”). I can’t remember last time I picked up ice in the summer half of the year – Icing clouds in summer in Central Europe are typically so high and convective that I avoid flying into them for other reasons.
P.S.: The discussion on legality is quite pointless. As long as nothing happens, nobody will care if it is legal or not. When something happens and ice has been a factor, insurers won’t pay and the pilot is dead anyways.
As long as no CAA (why does German LBA/BFA now come to my mind ?!?) has the great idea that they check the weather forecasts and fine every pilot of whom they think he plans to fly into ice with an unsuitable plane, nothing will happen. And when they do, it is up for a court to decide I a pilot has to “know” that in a cloud at -5C there is ice or not. But until this point: Why care? Nobody will change his behavior anyways.
and yes, it is exactly my point that therefore you rarely can legally fly IMC in winter with an airplane that is limited to “no flight into known and forecast ice”
That is a naïve simplification and out of touch with how aircraft are certified by manufacturers and how they are operated by pilots, if it’s really the case that is true and you are right, why not written as such in AFM? “flight in clouds is prohibited bellow 0C”?
I am sure aircraft manufacturers would turn the whole earth upside down on FAA if such strong legal wording is used in AFM limitation section, however, they can’t take the risk neither to ban/allow as such (limit own liability and retain a product) and most can’t push further to get FIKI certification due to costs, so the wording is left vague on AFM, unless we are talking FIKI !
Operationally, many US aircraft are non FIKI (de-iced or nothing) will happily fly in clouds in winter bellow 0C as you phrase it, it’s all possible and legal as long as WX & PIREP allows it…
Down here, everything is left to pilot and his regulator and who does not love that?
- You can plan as you wish if ice is not reported or forecasted (YOU don’t expect ice)
- You can’t fly in actual ice if AFM prohibit it, you have to avoid (including climbs)
- You can fly in clouds bellow 0C (AFM does not prohibit this)
Why CAA (or EASA) would even bother getting any interest in GA airframe icing accidents? is there any evidences based to apply US FIKI operational regulations as they are in the UK? do we really have that many? I mean like the thousands between Colorado & California? we barely had 3 in UK in the last 70 years (CAA is very serious on engine & carburetor icing, +1000 accident in last 70 years)
I am not sure about how LBA operate or icing accident stats in Germany, so I can’t opine much on how things works
GA regulations have been re-worded recently to be “evidence & risk based” (summarized as you are responsible and don’t crash)
Malibuflyer wrote:
fly IMC
We’re talking about flight in clouds, not flight in IMC. (Yes, I know that I’m nitpicking but there are situations where this distinction really matters and a lot of people confuse the two.)
When something happens and ice has been a factor, insurers won’t pay and the pilot is dead anyways.
Our insurer most definitely would pay. Whether the flight is legal or not is irrelevant except in very specific cases. The insurance company may then go after the pilot, of course, so for an owner-pilot the question may be moot, but not for syndicates, clubs, flight schools etc.
Malibuflyer wrote:
As long as no CAA (why does German LBA/BFA now come to my mind ?!?) has the great idea that they check the weather forecasts and fine every pilot of whom they think he plans to fly into ice with an unsuitable plane, nothing will happen.
It is interesting to hear Air Force cadets, if DUAL IFR in a non-FIKI aircraft, advising unable to enter visible moisture (via climb, or requesting vectors to avoid cloud) when OAT at their level is below +5oC, and I would suggest this is the correct practice for IMC operations in the UK.
In addition to safety risk assessment, you need to appreciate that if you are caught in icing conditions which are beyond the performance of the aircraft, and you request an emergency clearance to leave assigned altitude or controlled airspace via descent, it is likely to result in an MOR. Most ATC will not request that an emergency be declared, with a mandatory MOR, but the risk is there. If it is a regular offender that is requesting lower due to icing, there may be an MOR made in any event. Obviously ATC want you to request what you need, including declaring an emergency, rather than you falling out of the sky.
In winter most MEAs in visible moisture will result in icing.
RobertL18C wrote:
It is interesting to hear Air Force cadets, if DUAL IFR in a non-FIKI aircraft, advising unable to enter visible moisture (via climb, or requesting vectors to avoid cloud) when OAT at their level is below +5oC, and I would suggest this is the correct practice for IMC operations in the UK.In addition to safety risk assessment, you need to appreciate that if you are caught in icing conditions which are beyond the performance of the aircraft, and you request an emergency clearance to leave assigned altitude or controlled airspace via descent, it is likely to result in an MOR. Most ATC will not request that an emergency be declared, with a mandatory MOR, but the risk is there. If it is a regular offender that is requesting lower due to icing, there may be an MOR made in any event. Obviously ATC want you to request what you need, including declaring an emergency, rather than you falling out of the sky.
All very fair points and sound practices for UK IMC flying but they are operational PIC/ATC rules on how to deal with ice? (it’s very important to remind that in busy airspace, you have to take some on your skin: when icing is forested at controlled levels with tight vectors & altitudes, you will need B747 capability, even SET+FIKI may not be enough: I have done it in FIKI SR22 at FL80 and I will never do it again, especially in London TMA, flying VFR/IFR in the OCAS under is 99% safer), on OCAS clouds it’s even easier to avoid ice as it involve PIC flying his own route, level & heading…
MF remarks were on the legalities during planning phase, are Air Force cadets legally grounded anytime clouds are forecasted and temps are bellow +5C? or they can legally depart and tactically avoid as you mentioned?
PS: I think RAF still train and fly in winter clouds (even under 250kts without OAT/TAT spread) otherwise a foreign “FIKI Air Force” from a polar country could easily invade us
Malibuflyer wrote:
I can’t remember last time I picked up ice in the summer half of the year – Icing clouds in summer in Central Europe are typically so high and convective that I avoid flying into them for other reasons.
I suggest you keep a statistic of forecast ice in Europe around the year and see what happenes. With a zero degree level which is practically always in the IFR levels between ground and maybe 15000 ft but for some days, flying IFR in IMC will near always include sectors in which Adwice gives at least green (light ice). According to your mantra, this would mean a no go for anyone not FIKI certified. In practise it is not, and you quote the reason yourself: First of all by far not all forecast areas really produce ice and if so, it often enough is nowhere intense enough to be a real problem. Clearly in winter that is worse, but again, in winter, you’d basically ground the non-fiki fleet which is far from what happens. lots of times, icing forecasts predict icing actually below the usual cruise levels and in a very thin layer of stratus near the ground. Grounding all non-fiki planes for this is simply not happening and there is no reason why it should.
