What I find is that most ascents are really very well defined in where the cloud base is and where the cloud tops are.
Occasionally one gets two well defined layers, with a big gap between where again the temp-dp spread is big and obvious. I would be wary of this for any enroute purpose however (the layers in layered cloud can go up and down) unless the upper layer is obviously very high up say FL300, but then it is probably cirrus which, being ice crystals, probably won’t show up on the ascent anyway because the probe measures only the temp and the humidity. However tops at say 8k and the base of the next layer at say 20k is good for a short flight.
I will never “buy” the lack of an icing forecast as meaning anything useful, because – as I know – you can get a layer of what is conventionally called “low level cloud” which, if it lies in the 0C to -7C or so band and is 2k-3k thick, and really full of water, will ice you up comprehensively in the climb.
Ref that cloud where I picked up 35mm or so, I had earlier climbed right up through it, +1000fpm, and picked up about 5-10mm “only”. That was OK for the TB20 and would be OK for many old fashioned (but reasonably powerful) types, but, reading the anecdotal reports, might be a real problem for an SR22 or a DA42. The later substantial accumulation followed a bit of flight in sunshine in which sublimation cleaned it all off and a descent back into it, having got the surface OAT from the ATIS.
So the name of the game is always to climb up rapidly, and with ~300HP you can do that pretty well. Obviously avoiding IMC altogether is the best way 
Flying over the icing cold North Sea in winter time at night with risk of picking up some ice
We just returned Thursday evening from a flying trip to Bergen en Oslo. It was one of these trips of me together with my wife. We love doing trips like this. Just a few days away and venturing out. In Bergen we went to this great seafood restaurant on a small island off the Norwegian coast. We were taken there by a jet boat with some other restaurant guests and brought back to Bergen late in the evening by the same boat. In Oslo we went to a Norwegian Opera in the famous Opera house. Total trip was last Tuesday with a departure from Rotterdam and straight flight to Bergen of almost 4 hours, a short trip of 1 hour and 15 minutes (with a tailwind of 93 knots!) from Bergen to Oslo and finally with a return flight Thursday evening of 2,5 hours from Oslo to Rotterdam. The why of doing this trip is in the adventure, the activities we did.
Planned route Rotterdam to Bergen
We initially planned a route as straight over water to our destination as possible. We were wearing survival suits, each equipped with its own PLB, had a life raft ready to grab and hopefully a good engine. I had read a book on survival at sea just the weeks before.
The weather on departure from Rotterdam would be fine as you can see from the side view picture of the route weather. However, we would be approaching some frontal weather on reaching the Norwegian coastline. FL180 might not be sufficient to remain on top, but from my personal estimate of the weather I decided to go for it with a good alternate more inland and away from the frontal weather in case it was needed.
Here you see us in our survival suits.
Actual filed route
Just before departure last Tuesday afternoon, we filed a route that was just a little bit closer to the coast line. The reason was not the water below but “worry” about the radio reception on open sea if we were some distance away from the mainland. The idea of being out of radio contact while flying over sea and even for a part of the trip at night was not something I preferred. In actual flight we got a straight to our destination at Helgoland and were in radio contact with controllers at all times.
Frontal weather at Bergen on arrival
The frontal weather was there as expected. We were able to stay on top until the coast line, then were able to fly in between cloud layers until finally decending into Bergen cutting through the weather. The outside temperature was in the freezing range between zero and -20 degrees Celsius while in the descend, but we did not pick up any ice at all. The weather at Bergen was at the IFR minima for the cat 1 ILS approach, but went fine with lots of fuel reserve left and an alternate to divert to if needed. On the way there I checked the latest weather through a SAT link.
Trip from Bergen to Oslo
On the outbound flight from Bergen, the weather was again pretty IFR in Bergen with a cloud ceiling of 300 feet. The chart underneath the route showed (not depicted) better weather once away from Bergen with the clouds even disappearing while approaching Oslo. There was a Sigmet out for severe turbulence from FL130 and upwards, so we decided to climb through the mud and to fly enroute at the lowest altitude available when on top. This was at FL90 in uncontrolled airspace, but far away from the FL130 altitude. We did have a tailwind here of 93 knots!
Picking up ice
On the way to FL90 we picked up some ice, but later on had a great view of the Hadangervidda Highlands below us and a nice view of Oslo on arrival at Oslo Gardermoen airport and a great Opera and visit of the city. The flight back to Rotterdam was Thursday night and took just 2,5 hours. The flight was in total darkness with no visible moon out there and over open sea with almost clear weather from departure from Oslo to a thin cloud layer over The Netherlands: actually exactly as predicted in the vertical profile chart together with the Skew-T diagram and the infrared cloud top temp charts.
To fly over water or through potential ice clouds or not
So down to the issue of flying over water, potentially through clouds below freezing temps with the risk of picking up some ice or flying at night. I do it, but understand that others won’t. I believe we all have our own personal amount of risk we are prepared to take. This has to do more with the type of person we are. For me, I prepare, but accept the risks involved and then enjoy the trip. Others would never even consider flying out with the above risks involved. In the end, I believe it is a personal thing and my considerations will not work for someone else.
Hi Sjoerd,
that is some “top end” GA flying in our favourite birds! Way to go!
Great report….I guess Kjeller doesn’t have any (published) instrument approaches and I think you can only get fuel with a Statoil fob….but it is waaay cheaper and closer to Oslo….flying around Norway still ranks at the top of my flying experiences!
AQ
I thought about Kjeller, but opted for Gardermoen as destination as we would also be departing at night. Below 2 tons there is no mandatory handling, even though we took the handling this time to ease the filling up with AVGAS through the aeroclub gas station there.
On the way to FL90 we picked up some ice
I guess SR22 pilots might be interested in knowing how much ice you think can be picked up and the aircraft remains controllable, and what impact on the airspeed there is.
OTOH you may have full TKS which is a different situation altogether.
I used to think weather forecasts meant anything with regard to icing but now I think they mean very little – apart from forecasting major features like fronts, troughs, etc which obviously bring along the usual hazards.
The standard procedure for me is to keep away from frontal weather – apart from possibly overflying a “weak” front when enroute – and then one’s ice collection potential is going to be mainly in stratus cloud, in the departure/arrival segments, and I don’t think anybody can forecast anything useful there as far as liquid content goes. Temperatures aloft… yes. Those are normally fairly accurate.
A lot of pilots fly through fronts and I think it’s only a matter of time before they get bitten – unless they do it at low levels in the summer and below the 0C level in which case they should never crash provided they slow down below Va 
One front is not the same as another one. You can get a pretty good idea of how strong the front will be, if it is a warm, cold or occlusion front. Then there is always the option to turn around. There is a good DVD/download you can buy at Sportys in the US on flying in frontal weather. I am not flying through all frontal weather, but it isn’t that special if I do.
I think that our personality/character plays an important role in what we do or not. Take e.g. Dani Johnson’s GEMS programme where she distinguishes between 4 different character traits: sapphire, ruby, perl and emeralds. Sapphires are motived by fun, Ruby by winning (and money), Perls want to change the world and save the environment and Emeralds are the facts and figures types. There are lots of different/other programs like that of Dani Johnson, but I happen to know this one. My view is that we all respond quite different to the same challenge and that a lot of it goes back to our personal character of who we are. I am motivated by a challenge and by nature have no problem in taking risks in life, while others with another personality by nature will respond completely different.
Hi Sjoerd,
I wouldn’t dare to do it at night – but that’s a great flight. Very cool!
Hey Peter,
I guess SR22 pilots might be interested in knowing how much ice you think can be picked up and the aircraft remains controllable
you can have my SR22 for that test, as long as I don’t have to go :-) It’s very well insured! Just remember, it’s that RED handle on top!
Interesting discussion.
In light icing I find that I get a very swift loss of about 5/10 kt, which I’m guessing is loss of prop efficency. Then I’ll get a much slower loss of speed as drag builds up on the airframe. I have a 2m diameter prop so would estimate that the prop blade mid-span speed at 2000rpm would be about 300kts. So kinetic heating + centrifugal effect seems to give some icing protection to the prop when only a few degrees below freezing.
Personally I’m in favour of experimentation under controlled conditions with airframe icing. If there is going to be a surprise I’d rather get it with lots of warm VMC below cloud than the alternative. At least you will know what to avoid in the future. Where there is no other guidance you need to be your own test pilot.
Another issue not mentioned is that icing in convective cloud is often associated with lots of turbulence. Trying to climb with an iced-up airframe in turbulence is dangerous, it would be very easy to stall even with an IAS well above stalling speed. I’d usually go for a descent under those conditions, its much easier to keep the speed up.
