While everyone is concentrating on navigation, it’s also possible that this wasn’t a navigation mistake, but some other issue around. For example, it could have be the result of an engine failure (inlet servo icing has been known to happen) and he was forced down and either didn’t have time to make a mayday call, or it was never picked up due to the terrain. I could well imagine how someone might descend above MSA hoping to get visual, and the engine choose a bad moment to quit. Your attention would be taken very quickly and 1-2k feet could make all the difference.
JasonC wrote:
I don’t think this is exactly what happens. I think people get visual at the base of IMC and try to fly the valleys. Terrain rises and they end up in very marginal VMC (ie IMC) and hit something. Or they try to cloud break into a valley. Either way it is very tricky and while it may work if you know exactly where you are, one mistake and….
Peter wrote:
It is the SIA chart. I scanned it myself in 2010.
Yes sorry, my bad. It’s the 1:1 000 000 chart which no French pilot that I know seriously uses. I have the 2016 one here, it looks basically the same as your chart from 2010.
Nobody should use the 1:1 000 000 chart for avoiding terrain, you would take the 1:500 000 chart or even the 1:250 000 regional one if it exists for that region.
In the Alps we had a strong Föhn wind last week and the geostrophic winds depict the typical situation with high pressure SE of the french alps and low pressure NW of the crash region and the typical bend in the isobars.
So there could have been very strong rotor wind just at the ridge of these mountains and they can have an enormous downdraft like several thousand feet per minute which is impossible to cope with in a GA airplane.
Neal wrote:
In the Alps we had a strong Föhn wind last week
I don’t think that still persisted at the time of the accident. At least I don’t think it is compatible with the METARs that Mooney_Driver posted.
In my experience if you are going to Chambery or Annecy 6500 ft is the last altitude Geneva descend you to before they pass you to Chambery. Of course they know the procedure you are about to fly.
Rwy20 wrote:
At least I don’t think it is compatible with the METARs that Mooney_Driver posted.
I does match, indeed. North of the ridge the weather is beautiful and down in the valley often even no wind and nice and warm weather. It is very dependent on where the air flows and some valleys, if straight in the air flow have a lot of wind and others have no wind at all. What matters are the winds at altitude and not down in the valley. Things are very local during these wind situations. We happen to have BRK/SCT here with no wind 5° C and in the Gotthard valley in the Canton of Uri 25 km line of sight away they have CAVOK with 80 km/h gusts and 18° C.
I know some guys soaring a lot and they would never ever go flying in this pressure situation in the alps as you then need to know exactly where you can go and where is a absolute no-brainer. One of my friends told me of a downdraft in a lee rotor of 4000 ft/min which he luckily escaped in perfect CAVOK.
My condolences for the family and friends of the crew of D-ESPJ
SIA France south:
dublinpilot wrote:
I think there is a difference here between VFR only pilots and IFR pilots flying VFR, when flying in marginal conditions. I think IFR pilots are more inclined to go through a small bit of cloud if they know (or think they know) that there is nothing there. eg skimming the bottow of a cloud base, in and out of it. VFR pilots are more determined to stay well and truly out of the cloud because they don’t have the skills to get themselves out again if they don’t pop out again when expected.
That has the ring of truth. ‘Cloud breaking’, particularly in mountainous terrain seems like good sport to me, but very dangerous sport. As a purely VFR pilot who flies in moutainous terrain, I can tell you that I’d avoid it.
Obviously I have absolutely no knowledge of what happened in this very sad situation, and offer condolences and best wishes for all those personally affected.
It’s the 1:1 000 000 chart which no French pilot that I know seriously uses
Sure; but these were not French pilots. French use mostly the 1:500k IGN ones AFAIK – the ones which until recently didn’t go above 5000ft AGL. But I don’t think charts are a big issue for locals anyway (in most countries).
Outside France, the SIA chart has always (in my time) been presented as the only official government chart for France.
It is useless for elevations, but so was the Swiss ICAO chart which mixed feet and metres and could have caused me to do the same thing in 2004 when I first flew there, and thought the cows looked a bit too big… That chart probably killed a few foreign pilots in Switzerland.
That “6500” looks a very suspicious coincidence to me. Especially as they seemingly cancelled IFR and continued a descent and then levelled off at 6500.
inlet servo icing has been known to happen
Sure it has – as you well know 
But it needs -15C on the TB20 and probably other types (a DA42 gets a dual engine stoppage at -15C if you don’t use alternate air). On this occassion the temp was barely negative. At FL100 it was -1C (I was there).
I think there is a difference here between VFR only pilots and IFR pilots flying VFR, when flying in marginal conditions. I think IFR pilots are more inclined to go through a small bit of cloud if they know (or think they know) that there is nothing there. eg skimming the bottow of a cloud base, in and out of it. VFR pilots are more determined to stay well and truly out of the cloud because they don’t have the skills to get themselves out again if they don’t pop out again when expected.
Yes, very true.
It’s really sad to see where the crash happened given where FR24 stopped the tracking. It looks to me like they must have gotten lost, and am wondering whether the new Chambery TMA (they have turned the existing class E into a temporary class D – it’s notamed)has anything to do with it. You would never fly from overhead Annecy to Albertville that way on purpose when the weather is sub optimal like it has been for the past couple of days (persisting mist). There are 2 fairly easy ways – one involves more risk. First one is over the Annecy lake but requires some pretty solid local knowledge as you would need to over fly the Abbey very low before descending into the isere valley. Not a great idea in low visibility.
Given where the track stops it looks to me they mistook the Gorges du Fier for the Entrance to the isere Valley.
Also there may have been traffic on the ILS for Chambery, at their altitude they would have been asked to stay east of EY (what usually happens) which if not VMC would have put them very close to the terrain.
