Since getting my FAA IR last month I’ve been flying IFR within Germany on trips that were between 1:30 and 45 minutes and at FL60 – FL80 in a normally aspirated SR22. My very, very limited real world experience spans just 8 flights. And now I’m wondering about the need to file and fly high that I’ve read about so often.
4 of the 8 flights have been 80% in IMC and I staid at least slightly below the freezing level. Going higher on those IMC flights would have meant to climb to FL120 or even more with an increase in total travel time and likely to climb through subzero clouds.
It happens to be that my destinations have been VFR-only airfields with just one exception. It is very likely that I won’t be able to land there in VMC on a day with a lot of weather activity. German ATC seems to be perfectly happy with me flying IFR at “just FL60 – FL80”. I realize that I’m basically doing En-Route IFR. :-)
The aircraft I’m using has onboard satellite weather via the ADL device. I’m thinking that with that I should be able to go around too heavy precipitation thus avoiding the bad clouds while in IMC.
Based on my little experience so far I’m questioning the need for a turbo. I don’t have to cross the alps frequently and when I do I probably want to see the mountains to enjoy the view. When there is a lot of weather activity, there is probably also a lot of icing. With a turbo I can climb very well all the way to the top but on a 45 minutes flight I would go up through ice and down through ice, which is probably not a good idea, as it essentially means to fly in ice the whole flight. If I accept that even a FIKI TKS is just there to get me out of icing, then I were misusing it.
What am I missing?
I fly FL080-090 all the time because my engine is happiest at these levels. Sometimes weather forces me higher, but then I need my oxygen bottle.
The “need” to fly high is due to
In Europe, it is very common for cloudbases to be 2000-3000ft and tops say 6000ft. In the UK that puts you straight into Class A in most places. How bad it is elsewhere depends on where…
On better days you can get higher cloudbases and tops FL100-120, hence a need to fly higher. You don’t want to fly inside clouds if you can avoid it, because of turbulence, icing, and it is very tiring unless you have an autopilot. Generally, any time of the year in Europe, you can expect icing conditions at FL080-100 so you really do not want to be in IMC.
If you fly below clouds, you can find the terrain rising and/or the cloudbase lowering, and then you have a problem. Just climbing may not work if the terrain rises rapidly (unless you have an F16, and even that won’t do it in some places). So flying VMC on top is much more sensible. You can see what is ahead and you can avoid hazardous wx visually.
In some places (France and probably Germany) it is easy to fly c. FL070 on Eurocontrol routings but generally it doesn’t work well. It starts to work OK at FL100-120. For example to cross the Frankfurt area you need FL130 or so, otherwise you get a huge dogleg.
The longer the trip, the harder it is to reliably forecast wx along the route, which is another reason for VMC on top. In IMC, you could fly into a big convective monster which has just formed out of nowhere.
Flight on Eurocontrol routings is a wonderful way to fly distances. You get ATC working for you, and you get a low-stress flight with an implicit clearance all the way.
In terms of MPG, non-turbo piston aircraft tend to level off around FL080 so no great need to go much higher for that reason.
In some places (France and probably Germany) it is easy to fly c. FL070 on Eurocontrol routings but generally it doesn’t work well. It starts to work OK at FL100-120. For example to cross the Frankfurt area you need FL130 or so, otherwise you get a huge dogleg.
It does work very well in Germany, Frankfurt is the only exception, typically no overflight below FL140. I often do IFR at FL060-FL070 or so, all controlled with ATC. FL100+ in Germany has the advantage that it is a known traffic environment (airspace C), thus no surprises from non transponder aircraft or gliders.
When I fly somewhere and at FL060 in IMC I notice that I’m about to get negative temperatures and I don’t know where the tops are or know they’re high, then I am fine at FL060. I’ve done an IFR flight entirely in IMC for 2h from Germany to Hungary at FL050. I always considered climbing above IMC but eventually got hold of a commuter plane that took off in my vicinity and they told me “reaching FL200, still IMC” even though I could swear it can’t be more than 1000ft because of the amount of light shining through it. It is very hard to judge where the tops are and there is virtually no external information about it. More than once I thought I could make it, but then realized it’s higher than I thought and had to go back down because of aircraft performance, lack of oxygen, too short distance until destination, etc.
It is very hard to judge where the tops are and there is virtually no external information about it. More than once I thought I could make it, but then realized it’s higher than I thought and had to go back down because of aircraft performance, lack of oxygen, too short distance until destination, etc.
Yes – that is why I usually depart on a VMC path to VMC on top. The exception to that is if the cloud is either clearly thin or it is otherwise clear that the tops can be reached without getting into icing. I would never do IMC enroute long-distance… one is sitting there with no options.
One can usually get a rough idea of what to expect from the MSLP chart. Warm fronts tend to have tops FL200-250, and obviously plenty of icing on the way up (unless you get lucky). Cold fronts can be more “random” but I still won’t fly through them. Troughs tend to be a “PROB30 TEMPO TSRA” and a VMC path up can usually be found.
And yes this means no oxygen = no IFR, for me.
It’s really about keeping the maximum options open the whole time, and high altitude capability preserves the maximum options.
On a trivial trip out of the UK, say Shoreham to Le Touquet, I go Eurocontrol IFR at FL070. On Saturday, on the way back, Lille gave me a funny choice: fly back FL080 and you will get the Dover Sector (meaning: London Control) or fly back FL070 (as filed) and you will get London Information (meaning: no IFR clearance once in UK airspace). I went back FL070 and sure enough for the “silent IFR clearance dump” treatment – expected by me since I know the system and was descending anyway, but – as we have often discussed here – it would surprise a foreign pilot.
Otherwise, on a nice day, I level off FL100-110.
Based on my little experience so far I’m questioning the need for a turbo.
The problem is the freezing level. If your strategy is to stay below and the minimum IFR FL is maybe 60. In normal conditions you will need at least 12C at sea level. In the summer this will work out but if you want to fly IFR in spring, autumn or even winter this no longer works. Also in Europe we have lots of terrain. It is not only the Alps. Many smaller mountains push those minimum IFR altitudes up. Sure you can do a lot of fun flying with a Normally aspirated plane. But if you want to get a better dispatch rate a turbo is really a game changer. I went from a NA plane to a turbo plane and it makes a huge difference.
What am I missing?
Believe us, it’s much nicer to fly on top.
You are now still in the phase of being excited to fly “IFR”.
Very (very) soon, you will be turned off by being kicked around in clouds…
This could be a long debate 
but my take on the turbo scenario is that it doesn’t make a lot of sense unless one also has de-ice – because a turbo gives you ~FL240-250 which you will be using only to get above convective wx (due to the oxygen usage being high at those levels, and borderline-practical with certain types of passengers) and if you are going to be climbing up through stuff like that, the icing risk is just too great.
It’s funny that most non IR holders think an IR is for flying in clouds, but the reality is the exact opposite. I used to spend a lot more time in cloud when I used to fly VFR (damn I never said that) because of ATC and other restrictions on airspace access which prevent VMC on top under VFR in much of Europe (you can’t get high enough).
In the UK it is normal to depart “VFR” in Class G and then sit in cloud enroute, and this is legal (because while IMC = obviously IFR, the change VFR to IFR does not need a clearance so is done wholly inside the pilot’s head) but it tends to be done at low levels like 2400ft/3400ft where there is no icing – except obviously in the winter.
The aircraft I’m using has onboard satellite weather via the ADL device. I’m thinking that with that I should be able to go around too heavy precipitation thus avoiding the bad clouds while in IMC.
As the inventor of the ADL110B and ADL120 please be cautious navigating close to embedded thunderstorms using datalink weather. It is a great tool but the weather data will never be real time. So things could have changed and if you fly close to embedded CB you need on board radar to verify your path is still clear.
When flying in a CB area the best strategy is to stay VMC. Use datalink weather in order to choose the best path which will keep you VMC and clear of the CB.
As the inventor of the ADL110B and ADL120 please be cautious navigating close to embedded thunderstorms using datalink weather. It is a great tool but the weather data will never be real time. So things could have changed and if you fly close to embedded CB you need on board radar to verify your path is still clear.
When flying in a CB area the best strategy is to stay VMC. Use datalink weather in order to choose the best path which will keep you VMC and clear of the CB.
And to follow up on this I use the ADL120 to decide whether I want to descend down into an area (or go near it at all). RADAR is the only useful way to navigate around cells in IMC. Stormscopes no good really when close to anything convective other than as an additional confirmation.
