Peter wrote:
I hope to be installing the full TKS system this winter
I never thought the various weather sites offered any more certainty than the SIG Wx, as far as CBs and moderate+ icing are concerned. They give spurious precision because they show a much higher resolution, though.
I would argue that 90% of the time the sites (mostly plotting GFS data) don’t tell you anything which is not obvious from looking at the MSLP for 10 seconds…
What the IR etc sites do tell you is the actual conditions as to e.g. cloud tops, convection, lightning etc. and that will indicate whether the flight can be done as VMC on top which is always the best way by far.
What system did you settle on?
For the TB20 there is only one system: the TKS from CAV Aerospace. There is a thread somewhere here. Obviously I will post a report, as it goes along, because it will be installed by my A&P/IA and myself. I did look for people who have done it before, and found a couple (Air Touring did several) but none could be organised for various reasons. The TB20 installation is very neat in the way all the stuff goes into the unused void under the luggage compartment floor.
Even being equiped with de-icing by TKS, I plan to avoid icing. The weather information nowadays is realy good to build a picture of the situation. I like the forecast of the german DFS in combination with the picture delivered by the autorouter. As you can see in the picture of today you can identify where the most icy layer is. That helps a lot when you are getting ice in flight to decide to climb or to decent.
Also the ADL inflight weather helps because with the IR depiction and the perception radar, the decent or climb or turn back decision will be easier.
In flight when building up ice I inform ATC immediately to get a level change. In my experience you will get a immediate response. They are also interested to get you out there.
Flying at night in IMC around the freezing level, I always activate TKS in the anti-ice mode. Additionaly I switch on the TKS light to have the wing visible.
And one last thing: if you have to cross a front, doing it in a right angle will put you earlier out of the dangerous aera, than following the frontline. So crossing and behind the front going back to the original direction might be often the better choice instead of heading forward and staying in the “shit” all the time.
I was looking at the new TBM 930 specs and this brand new 3.9mill USD beauty still “only” have the usual pneumatic de-icing boots.
Why is that? I know there has been accidents involving TBMs and ice….
Michael_J wrote:
Why is that?
Because a single propeller-turbine does not provide enough bleed air for heated wings. Many light and even some medium sized business jets as well as regional turboprop-airliners do not have engines which produce sufficient bleed-air for anti- and/or de-icing and either come with boots or TKS. There are some electrical systems which either require huge amounts of current or are still in a kind of unproven experimental state.
There is absolutely nothing wrong with de-ice boots. A reliable and decades-long proven system. And a lot cheaper to install and maintain than every other means of providing anti-/de- icing capability.
And no: I will not discuss on any public forum how de-ice boots are to be operated. Come fly with me and I’ll show you…
Speaking of boots, Ernest Gann (Fate is the Hunter) describes a near death experience (one of his many) where boots bridged right over and continued to cycle underneath the ice bridge.
Socata’s position is that this is not possible. Other positions are that “modern” boots don’t suffer from this. Is that true?
I am not sure if this is off topic. This seems like a very general icing thread, so anything goes 
I was going to merge some of our many icing threads (found with a search on “icing”) but decided not to because they are often usefully specific, before getting off topic…
Peter wrote:
Socata’s position is that this is not possible. Other positions are that “modern” boots don’t suffer from this. Is that true?
I have no idea. Personally, I would classify this bridging (which I have never seen myself) as “severe icing” which by definition is an amount of icing which the installed system is unable to cope with. I guess the shape of the wing and the speed at which the air flows over the wing has a lot of influence on this bridging phenomenon. I have flown a lot on Cessna 421s in all weather. I have operated the de-ice boots on this aircraft on very few occasions because obviously that wing does not tend to accumulate ice in the first place. On the Seneca I have seen it a lot more, but the boots were always able to break the ice which was then carried away by the slipstream. The “art” of operating the boots is to pick the right moment to turn them on. Not enough ice and it will be flexible enough to keep sticking to the boots, too much and it will not break. The usual value of 1/4 inch or 5mm found in some flight manuals and text books has so far worked fine for me.
Our aircraft is equipped with alcohol prop-de-ice and boots on the wing. The certification is so old that it is approved for flight in light icing conditions, which would not have been put in an AFM in the last 30 years. From an experimental learning point of view, this puts me in a position where I can sit in some icing conditions with the prop de-ice on and watch as the ice builds, though I would only do that in the knowledge that I have an alternative plan.
Icing is very variable, and the biggest problem is that the same situation (to the eye) can offer anything from zero icing to “oh my god” icing. That said, in stratiform cloud, I find that it’s usually quite easy to find a level at which icing is minimal. Last week, I climbed from 90 to 100 on the outbound to avoid some nuisance icing. On the way home, I descended through an icing layer that was about 3000 ft thick (80 down to 50) at the top of some stratocu. It would have been unpleasant in the cruise, but at 1000 fpm down with known warm air below, it was routine. I would avoid Cu above the freezing level like the plague.
I reckon a reasonable dispatch rate is possible in flatland from late March to late November. In the winter, the alternative-plan aspect can prove difficult to arrange, and, because of the potential for ice, I plan and execute many fewer flights. In the mountains, all bets are off.
I would also offer the EGAST leaflet on in-flight icing
This NTSB Safety Alert is posted in one of trainign facility in Poland, never mind it’s EASA.
http://www.ntsb.gov/safety/safety-alerts/Documents/SA_014.pdf
loco wrote:
Looking back, the ice wasn’t actually that bad and there was no speed degradation. Still, it was one of scariest moments in my life.
It takes very little ice on the DA40 to screw up your climb performance and you quickly lose 5-10 KIAS in level cruise. The one I fly is equipped with a NA IO360. With the TDI you would have more power than me at FL100, but still. Without any deice equipment I would not fly (in clouds) anywhere near an area where moderate icing is forecast, especially with the 0-isotherm as low as 2000’. That can quickly ruin your day.
