Val d'Anniviers Airplane Crash
 

http://static2.hln.be/static/FOTO/pe...20110211183320

No survivors.

Sion is LSGS not LSZS.

I stand corrected; thank you.

My comments on radar and MSLP still stand. No apparent high altitude weather.

From here

METAR LSGS 111220Z VRB03KT 9999 FEW110 11/M07 Q1019 NOSIG

TAF LSGS 111125Z 1112/1121 VRB03KT 9999 FEW110
BECMG 1113/1115 CAVOK=

No real difference.

This shows nothing before 1800Z now but you can see no significant high altitude cloud over most of Switzerland.

I am no crash investigator but to me it looks like they tried to land along the top of the ridge but thoroughly stalled and hit the ground with a high vertical speed and low horizontal speed. A bit like the Turkish B737 in Amsterdam. The huge (1m) boulder about 2m behind the elevator seems undisturbed. Except for footprints, the snow is undisturbed all around.

Why would you ever want to land there though? From that position and at FL 120 you can make it down to the Rhone plain and various airfields there with altitude to spare even with dual engine failure.

Perhaps stalled it when he found he couldn't clear the ridge and it was too late for a 180?

How's a B55 doing with 3 adults and two teenagers?

It's a pretty good stall though, shame no one survived, by the shape of the fuselage there was a possibility of surviving?

What is the single engine ceiling of this aircraft, at MTOW?

Fully stalled one is probably doing about -10000fpm i.e. 100kt. That is what happened, apparently, with AF447.

Huh? I can't speak for either a Baron or an A340, but the planes I fly can be held in a full stall and fly quite decently, coming down at around 1000 fpm. I do this routinely in my plane (TR182) and the Pitts, and have done it in a 172, Citabria and Decathlon. It would seem kind of weird doing it in an A340 but I don't see why it would be much different.

I wouldn't want to hit the ground even at that kind of vertical speed, though.

A spin is a different matter of course, but it doesn't look as though he was spinning.

The weather in and around Sion, especially in the valley, can change within minutes. It was a procedure of ours to go and eyeball up the valley pre departure because you couldn't rely on the actual weather report still being relevant.

I've actually got airborne in, essentially, CAVOK conditions, done a 180 back down the valley to be confronted with a huge banner cloud that wasn't there two minutes earlier.

Must have been hell of an impact, looking at how the wings have deformed yet the tail looks ok, so probably nose low.

It does make one wonder why you'd try to land there rather than circle off down the valley and use your height. Does to me look like they stalled, the Baron has quite a high stall speed if I recall correctly.

That's because you still have a forward airspeed. My TB20 glides down at about -1000fpm.

If one killed their airspeed completely, that's different. It won't be easy because any certified single engine plane, loaded within the envelope, will go nose-down and recover.

But if you were to overload it heavily in the back, then it might not recover, however, and will just go straight down.

This is outside my area but multi engine planes do not have to meet the 61kt Vs and AIUI do not have to recover from a deep stall. This is one thing which came out of AF447; an A330 can just stall/spin and plummet straight down, unrecoverably.

I reckon this one came down at a huge VS.

LSM - I agree; nothing suggests they were VMC or IMC at the time of the impact. But looking at the terrain, and the fact that they are pointing just right along that ridge, I reckon they tried to come down on it.

Picture 4 on 20 Minutes Online - «Le pilote et une famille sont morts» - Romandie gives a good overview of the surrounding area.

They have crashed at about 3.000m at pointe de la Forclettaz.

The family was French with children aged 15 and 11

Does anybody know anything more about this, e.g. ATC interaction?

It does seem a bizzare accident. Obviously not a straight N2195B-type CFIT. It's obvious the plane went more or less straight down, in a straight and level attitude, perhaps a bit nose-down. Could be fuel exhaustion followed by less than competent aircraft control, or pilot incapacitation followed by a passenger attempting to fly.

The temperatures (+11C at Sion) don't seem low enough for a dual engine failure due to fuel icing. The Aztec has been reported to ice up below -15C. I know nothing about the Baron. But it's possible, if they were flying high (say FL200+) to start with.

It is also quite possible for that ridge to have been one of not many sticking up through a high altitude cloud layer. This might explain why they did not go into the valleys surrounding the ridge.

No signs of post-impact fire either, despite all the fuel tanks having been most likely torn open. It doesn't suggest large amounts of fuel on board, at the time of the crash.

As a side note, looking at those pictures I'm always grateful for the people in the rescue/recovery team: a job as valuable and essential as it is gruesome.

Must be horrific for them, especially when kids are involved. Not sure I would choose to do it.

I was flying VFR SEP in Switzerland on the day of the accident, I'm based and was flying in the eastern part but have a good look at the weather and particularly winds for the whole of the country before taking off.

There was the usual mist over the 'plateau' that morning but around Sion and over the Alps it was 'grand beau'. Winds were SSW 15-20Kt between 8,000 and 13,000ft.

The accident site is a ridge above the Pont de Forcletta at around 3000m or 9500ft.

The aircraft was based at Geneva, it flew to Lausanne, picked up the 4 passengers and departed for its sightseeing flight. The pilot apparently intended to land after this at Sion.

The accident site is outside the Sion CTR/TMA in Class E, the pilot would not have had to be in contact with any ATC unit but might have been in contact with Geneva Information.

I flew the Baron in 1970-71 at Hamble but never at high altitude with 5 on board. I would think that the aircraft was above its single engine service ceiling, however it looks as though the aircraft impacted vertically with zero forward speed. I would speculate on pilot incapacitation followed by stall and spin.

There don't appear to have been any witnesses, I would think that the flash memories of any installed GPS set and passenger cameras will yield important clues.

Interesting to see how the wings are draped over both sides of the ridge. I can see how it supports the idea of a near vertical descent, or one normal to the ridge slope.

Ridge level winds are normally considerably more than that reported in the valley bottoms. There can be eddies from adjacent peaks and spurs, but downwind of a ridge is a very nasty place to be. The sink can be enormous. Directly over the ridge is a transition zone with considerable curl over. I would lean to an angled approach from downwind that hit heavy sink.

How close to the terrain would you need to be to get a sink rate exceeding the rate of climb of a Baron at MTOW at 9500ft, with ~ 20kt winds aloft?

Quite close I would think. A few hundred feet; possibly a lot lower.

I don't do any "mountain flying" but have flown straight over the top of the Alps and the Pyrenees a number of times.

However I don't believe winds could have done this. The aircraft hit the ground with a massive vertical speed. Looking at the pictures, at least two seats were ejected out of the cockpit, several yards out, ripping off the roof in the process, all despite a near-zero horizontal speed. One to the right and behind, one to the left and over the LH engine. Both ejected with occupants still strapped in (visible in the first picture). Horrid.

Looking at the pictures there seems to be higher terrain somewhere near that ridge. I don't know what the winds aloft in the area were like at that time, but a priori if they were on the lee side the effect of a downdraft or worse, a rotor (:uhoh:) is a distinct possibility.