How far above/below the terrain was the aircraft when it encountered the downdraught?
Depends on the reference point. At most 1200ft above terrain directly under them, but laterally level with or just below the ridge (cf. report p. 34).
For those who can’t speak or read German – other than the obvious things (insufficient height reserve, flying leeward of a crest, not recognising the downdraft etc.) there is one interesting bit: the pilots tried to counter a downdraft by pulling and increasing the angle of attack, and still had sufficient height to scrape over the pass – but then they entered an area of updraft which increased the angle of attack and they stalled.
So additional lesson for mountain flying – avoid high AoA / keep a good speed reserve when in a downdraft!
Yes if you pull up in downdraft your AoA gets near the edge and as you slowdown you will lose lot of height as you will spend more time in sink with steep L/D while barely gaining any RoC, if you after hit an updraft you hit the jackpot on AoA stall which comes badly as now you have no height left…
Really surprised how such good experienced mountain crew lacked basic ridge crossing and basic speed margins during their execution and just end up pulling on a stall trying to outclimb terrain? I wonder if they ever stalled JU52 ever low and high density altitudes?
You pitch down in downdraft and you pitch up in updraft, so that the AoA stays on same safe and efficient low drag value while losing minimal height as you spend less time in sink and more time in lift (soaring101)
Same if you find yourself in 40kts rotor behind a hill, some ridge/wave hunters call this the ideal condition, you pitch 90deg toward the ground as quickly as you can, if you pull up to slow down you get draggy then eaten alive by dragons (wave101)
Ibra wrote:
Really surprised how such good experienced mountain crew lacked basic ridge crossing and basic speed margins
The surely knew – and even reached this as FI.
Unfortunately the behavior of the Pilot as it is reported in the accident report is consistent with a “rules are only there for people who are not good enough to know it better” mindset.
Malibuflyer wrote:
Unfortunately the behavior of the Pilot as it is reported in the accident report is consistent with a “rules are only there for people who are not good enough to know it better” mindset.
If you read the report throughout and the annexes, there is a clear tendency to demonize almost the whole Swiss civil and military aviation world. While it is clear that there were substantial problems in the operation of Ju Air and there was conduct not acceptable by some of the people involved, the report goes much further than that, basically suggesting that ex air force pilots are generally unsuitable for any civil ops and so on. I think that the accusations in the report need to be taken with a bucket of salt as they go much too far and are quite unfair to quite a lot of people.
Fact is, nobody knows the Alps better than the military pilots of Switzerland. Fact is also that that may lead to some higher degree of readiness to take risks, which is not appropriate in this kind of operation. With this I fully agree and it is absolutely correct that the report points this out. However, my feel is that it goes much beyond the actual task of an accident investigation report and reads more like what a state attorney would produce in order to formulate indictments. That on the other hand is not in the sense of Annex 13.
We have seen in many cases where very experienced pilots came to grief that their experience may have given them a confidence which was not warranted. In this case, a number of factors combined (classical Swiss Cheese Model) to result in an accident. They had hot weather, they had, unbeknownst to them, a fault in their WnB calculation which put them beyond aft limit, they wanted to give their pax a spectacular experience (Martinsloch) as they did many times before. Yet, this time, everything came together in an accident. And, it was only very lucky that this did not happen before. Clearly, the crew failed to do their job properly on this and preceding flights and it is only correct that this is stated as is in the report.
However, the gist of the report goes far beyond that and puts straightforward blame on just about everyone in a fairly general way and puts the thrustworthyness of two major carriers as well as the FOCA into a general suspicion which I think shoots far beyond the goal of improving air safety.
We shall see what the fall out of this is, one of the results is already known clearly, there will no longer be any historical aviation possible in Switzerland, not only by this operator, where this may even be warranted, but by anyone, also those who operated fully within EASA criteria.
Were the same approach taken towards other accidents, I suppose we would not see much aviation anymore.
Fact is, nobody knows the Alps better than the military pilots of Switzerland.
Fact is, despite their knowledge of the Alps, of hot weather effects, and of the effects of a northwesterly blowing across that ridge they still chose to ignore the risk – while being fully aware of them in advance. And this not once but repeatedly, demonstrated by data. WnB was not a factor. How you get to demonising from that is not understandable. Operating a transport-category airplane with these parameters is an accident waiting to happen not a demonisation. I don’t think relying on luck for the Swiss Cheese model last hole not to align is a long-term survivable strategy.
Re – shooting far beyond the goal of safety: JuAir was allowed a TBO of 1’500 hours on their engines, despite the manufacturer originally calling for 150-300 hours, and no supportive data to increase the TBO (if anything repeated powerplant failures showed that a TBO of 1500h was vaporware). Don’t think that’s demonising, is it? Just pinpointing a culture of consciously choosing to deviate from facts based on an own desired, romanticised, view of the world.
T28 wrote:
Don’t think that’s demonising, is it? Just pinpointing a culture of consciously choosing to deviate from facts based on an own desired view of the world.
No, clearly this is inacceptable. What has happened within Ju Air and the oversight not done as required has destroyed 30 years of work and confidence and therefore needs to be sanctioned as necessary and with the full extent of the law. Prosecution however is NOT the task of the Annex 13 report.
However, the hint that generally pilots from the military are not suitable for civil operation because they generally take too much risk is. Hinting that the airline employers of both those pilots tolerate this kind of thing is. Hinting that other operators who operate similar planes would do the same is.
That however does not mean that NOBODY can operate historical airplanes safely, that one can if at all only do this with 6 people on board and so on.
Hinting that the employers of both those pilots tolerate this kind of thing is.
Well it’s not a hint – it’s an established fact that JuAir did tolerate that behavior and no corrective action was undertaken.
If you dig around the general area of piston charters – either A-B or A-A pleasure flights – you will find dodgy practices at most of them.
It comes with the territory. There isn’t enough money being made, the hardware is old and shagged and too expensive to fully fix everything that’s knackered. The further you go down the food chain the more you find. One example from the bottom is the famous G-OMAR… A lot of dodgy stuff went on in past decades in the twin (or triple) piston services to the Channel Islands; they didn’t crash because the whole route is over water so providing you are higher than the waves there is not much to hit and you can get under any wx, except fog 
The same general culture will be found everywhere. The pilots generally think they are absolutely brilliant, and airport bars would be much poorer without them.
Not universal by any means but a lot of stuff goes on which would not be allowed in scheduled twin TP and jet ops.
