The wind plays its own music

[ARCDOC]

Best forum readers!

I thought that it would be a good idea to post something here, after writing the article about the theory involving a katabatic wind. Me, Andreas, Ekaterina and Artem, made an expedition to the pass in Jan/Feb, which is shortly described together with the new theory. You can find it under “The Swedish-Russian Dyatlov Expedition 2019” on this site’s Home page – or in my constantly updated blog. A link to the latter is found along the article mentioned above. Before commenting, I would suggest that you read the theory in full.

I have tried to build the case out of my own experiences from mountainous areas and by experiencing the Dyatlov pass/Auspiya valley during the same time of the year as the Dyatlov group. I have also compared the Dyatlov event to the Swedish accident of Anaris in 1978. The latter which in many ways mimics the circumstances in the Dyatlov pass - affected by a gravity wind (katabatic wind).

I have experienced many positive feedbacks on the theory, but also much criticism. The latter is very welcomed in order to improve the knowledge of the event. So please, when objecting, try also to explain why you object to details or any larger unfolding event during the evening/night of February 1st in 1959 - involving a possible katabatic wind. This, so that we can build a solid case. To my surprise most of the people objecting to the theory are less favourable of the idea of leaving the tent without giving a thought of staying – this in case of a falling/gravity wind. It is important to solve the “leaving the tent” situation, because it is this specific act that more or less leads to the subsequent events. So let me first make one thing clear. I am not talking about any wind or any storm. The density and gravitational force of a katabatic wind is brutal. A storm would mostly give you the option to dress and to stay/leave the tent under rather controlled forms. Furthermore, never forget the coexisting low temperature, both during the night and the cooling effect of a gravity wind rolling down the gradient. So again, we are not talking about severe winds or a storm of wind speeds up to around 25 m/s, but about possible wind speeds above that. Even though we should be open for wind speeds during a katabatic event of around 20-25 m/s. Remember that the katabatic wind recorded during the Anaris event was “only” around 20 m/s. The cooling effect was then around minus 50 degrees Celsius (-58 degrees Fahrenheit).

Many would argue that the Dyatlov group could have stayed in the tent. But I would argue that crawling back under the snow covered tent, if possible at all due to the conditions involving a gravity wind, wouldn’t have helped them - which they wisely and obviously realized. Yes, the tent would have been better secured with the group inside, but the cooling effect under a gravity wind would eventually have killed them. Furthermore the torn tent was already made unsuitable for this option. In fact - it was exactly this that killed the Anaris group, where the only person escaping the shelter was the only survivor. He was in constant movement and ventured elsewhere, while the rest froze to death.

So, let us start there – and let the ideas, concerns or additional viewpoints flow.

Sincerely,
Richard Holmgren

[sarapuk]

Best forum readers!

I thought that it would be a good idea to post something here, after writing the article about the theory involving a katabatic wind. Me, Andreas, Ekaterina and Artem, made an expedition to the pass in Jan/Feb, which is shortly described together with the new theory. You can find it under “The Swedish-Russian Dyatlov Expedition 2019” on this site’s Home page – or in my constantly updated blog. A link to the latter is found along the article mentioned above. Before commenting, I would suggest that you read the theory in full.

I have tried to build the case out of my own experiences from mountainous areas and by experiencing the Dyatlov pass/Auspiya valley during the same time of the year as the Dyatlov group. I have also compared the Dyatlov event to the Swedish accident of Anaris in 1978. The latter which in many ways mimics the circumstances in the Dyatlov pass - affected by a gravity wind (katabatic wind).

I have experienced many positive feedbacks on the theory, but also much criticism. The latter is very welcomed in order to improve the knowledge of the event. So please, when objecting, try also to explain why you object to details or any larger unfolding event during the evening/night of February 1st in 1959 - involving a possible katabatic wind. This, so that we can build a solid case. To my surprise most of the people objecting to the theory are less favourable of the idea of leaving the tent without giving a thought of staying – this in case of a falling/gravity wind. It is important to solve the “leaving the tent” situation, because it is this specific act that more or less leads to the subsequent events. So let me first make one thing clear. I am not talking about any wind or any storm. The density and gravitational force of a katabatic wind is brutal. A storm would mostly give you the option to dress and to stay/leave the tent under rather controlled forms. Furthermore, never forget the coexisting low temperature, both during the night and the cooling effect of a gravity wind rolling down the gradient. So again, we are not talking about severe winds or a storm of wind speeds up to around 25 m/s, but about possible wind speeds above that. Even though we should be open for wind speeds during a katabatic event of around 20-25 m/s. Remember that the katabatic wind recorded during the Anaris event was “only” around 20 m/s. The cooling effect was then around minus 50 degrees Celsius (-58 degrees Fahrenheit).

Many would argue that the Dyatlov group could have stayed in the tent. But I would argue that crawling back under the snow covered tent, if possible at all due to the conditions involving a gravity wind, wouldn’t have helped them - which they wisely and obviously realized. Yes, the tent would have been better secured with the group inside, but the cooling effect under a gravity wind would eventually have killed them. Furthermore the torn tent was already made unsuitable for this option. In fact - it was exactly this that killed the Anaris group, where the only person escaping the shelter was the only survivor. He was in constant movement and ventured elsewhere, while the rest froze to death.

So, let us start there – and let the ideas, concerns or additional viewpoints flow.

Sincerely,
Richard Holmgren

Its a good post. Welcome to this great Forum. However, Iam very doubtful about any kind of wind playing a part in the demise of the Dyatlov Group. Not only do I believe that no wind however strong could have driven them to abandon their refuge, but also I dont believe any kind of wind played a part in some of the very serious and highly unusual injuries to some of the Group. I have posted replies else where on the Forum re my stance re winds. But here goes again. The Wind be it Katabatic or otherwise would need to have been so strong to drive the occupants from the Tent that it is almost certain that the Tent would have suffered very heavy damage. But it was not actually damaged as such. The tent had cuts or tears in it and these could not have been caused by a Katabatic wind.
It is claimed the cuts or tears were man made. Also the Tent was not moved from its pitched location, and such a Katabatic wind would almost certainly have shifted the Tent. And I have been in a Tent when very strong winds have blown trees down in the vicinity. Had the winds have hit my Tent it too would have suffered severe damage. I believed the safest place to be when those winds were blowing, was in the Tent. Imagine being on a mountainside in severe low temperatures in a remote part of the World. Would you abandon your Tent. If the Katabatic wind is that strong to remove you from your Tent then it will also remove your Tent. And all things point to the Dyatlov group walking a mile, poorly dressed etc. Would you do that in such a wind  !  ?  Thats why I can not subscribe to the Katabatic wind theory.

[ARCDOC]

Thanks for welcoming me and for your thoughts!!

Just to clarify parts of the theory that you commented upon - according to me; 1) the tent wasn't ripped by the wind, and 2) the snow was put atop to keep it down behind the snow shelf.
And then the answer to your question; 3) yes, I would have acted like the group in the case of a gravity wind.

Many Thanks!

[Star man]

Have also posted this on the other thread.

I have just read the whole theory.  It's very interesting.  I like that it provides an explanation for the flashlight being found on 10cm of snow on top of the tent.  This has been a detail I have been thinking about.  There are other possible explanations for this, but I think Richard's is a good one.

The theory kind of reminds me of the movie "The Day After Tomorrow", where cold air is drawn down from the upper Troposphere and freezes everything instantly.  Obviously the movie is just fiction, but I suppose a significant downdraft of cold wind is credible on Kholat Syakhl.

Let's consider the tent.  It was two tents sewn together and had many makeshift repairs, which means it probably wasn't fit for high winds.  Also, if the temperature suddenly dropped to below -50C could this affect the material of the tent?  I am not an expert of fabrics but most materials become embrittled at very low temperatures.  I would not be surprised if the fabric became stiff and therefore the repairs more likely to fail.

If the tent suddently failed due to high winds and low temperatures it would have put the team in a very dangerous position.  I think what Richard is saying is that they didn't leave the safety of they tent.  Instead, the tent was nor longer a safe place so they had to leave to find somewhere safer.  It's a credible scenario.

However, there are things that need to be considered in detail:

If the group had time to walk a mile down the slope, they should have had time to retrieve their footwear from the tent and some better outdoor gear?  Slobodin at least had time to put one of his boots on, so why not the other.  If the events happened suddenly, then their hands would not have been too frozen to put on their boots and collect essential equipment.

Why did Semyon have his camera around his neck?  Was it just a coincidence or was he taking photos just before the events began.  Semyon and Thibo were probably on duty being betters dressed, or maybe they had gone outside to relieve themselves.

The autopsy reports are odd.  There are peculiarities around the cause of death of the group.  Dorishenko's Edema, urine levels inconsistent with freezing to death.  Coats unzipped, gloves in pockets.  The two Yuris had a fire going that burned for an estimated 1.5 hours.  Why did they die?  No toxicology report in case files? Why?  Has just got lost over time?

The chest injuries - consistent with a sudden and fast impact, such as falling 5m to 7m.  Equivalent to about 2 to 2.7 tonnes of force.  Could a collapsing snow den cause these injuries?  Luda had a smashed nose, and a large bruise on femur.  Semyon had a large cut on the right side of his head, exposing the skull, ( the same side as his crushed ribs).  Injuries still seem more likely to be from a fall than collapsed snow den to me.

Why set up two separate areas: 1. The cedar and fire. 2. The ravine and snow den.  Why not build a fire near the snow den?  In my mind one possible reason for doing this is that some of the team had already sustained significant injuries.  Maybe they fell from the tree or fell in the ravine and therefore a shelter had to be built for their survival.

I like the explanation for the injuries of Dorishenko.  The armpit scratches etc.  I too also think that the two Yuris got these either trying to climb up or down the cedar with frozen extremities.  It seems the most likely place to get the minor scratches and abrasions.

All in all I think it's an interesting theory, particularly as a reason for leaving the tent and the camp and it warrants further consideration.

I take my hat off to you for retracing their steps to gain a further insight into the incident.

Regards

Star man


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[hanno]

I see two weaknesses for the katabatic wind theory:

1) If there was such a strong wind, wouldn't be the tent be much more damaged? Based on the reports and pictures the tent is more or less intact except from the cuts. Even the skis are still standing upwards.

2) Although Richard would have left the tent in a similar situation, I am sure most people wouldn't have reacted so. Also in the Anaris accident the people stayed inside the tent and this was years later than the Dyatlov accident. In my opinion it is definitely not the "normal" behavior that when there is a strong wind you leave the tent and search for shelter in a near wood.

But we all know that the Dyatlov case is far away from being normal, so probably there is no normal solution.

I could imagine the following sequence of events:

Some of the Dyatlov group are just inside the tent, light dresses and preparing for dinner or sleeping. Some are better dressed and still outside (because they are still fixing something, because they want to relieve themselves ...). Those that are outside see a katabatic wind. They don't know what it is, but it looks quite impressive. You can google for videos and you will see that indeed can look very spectacular.
Because of this, Semyon grabs his camera because he wants to make a picture.

Then from one second to the other the katabatic wind hits them with immense coldness.

Option A:
It becomes so cold that they can only put on some of their clothes. Hastily they leave the tent are in the hope to make a fire in the woods and stay there until the wind gets weaker.

Option B:
They all leave the tent because they want to better attach it to the ground. They recognize it is not possible, an so they put snow on the tent so that it can't be swept away from the wind. Then they also leave the area. Maybe those who were light dressed just left the are while those
better dressed put snow on the tent and then followed.

Is this a plausible story? I would say yes, it could have happened so (or similar).

Is it the theory that matches best to all the given facts? I would say no, the military involvement theory matches better. But this is my personal opinion.

Is there a way to prove the theory right/wrong? As with all theories: No.

[ARCDOC]

Star man – great comments and input! Thanks!

Yes – the flashlight issue is a bit awkward. It looks as if it was put there afterwards, but it could in fact have been placed there by the group. Perhaps it was buried much deeper during the event, but was fortunate to stay in position after that the snow was put atop – and had blown away (with its front sticking out from the snow). In any case, it would probably have been sheltered by the snow shelf, like the collapsed tent in itself. A remarkable phenomenon that I have felt with these kind of winds are that they could actually leave smaller or thinner objects in place. Usually it’s the large volume objects that are affected. A falling wind this strong, is usually so fast that it skips the holes and cavities. It’s like when you drive a car fast and the bumps in the road become less obvious. This could explain why some footprint are saved and some not. Another thing that I have seen are that masts and poles often stays in place – its as if the strong vortex created behind the object is pushing it against the wind. But, as you say – there might also be other explanations for the flashlight being there.

Funny you mentioned the The Day After Tomorrow – we use to joke about that at home… “we got a temperature drop!”. Anyhow, yes the situation of the downdraft is comparable albeit way much weaker in the pass. Not Hollywood style.

As you also write – the tent was stitched together with yet another canvas and with makeshift repairs. What you raise next is very interesting in many aspects – how extreme low temperatures would affect the tent. The canvas material that we brought with us was worse in the Auspiya valley since it was more humid there. At one point I could take my Fjällräven anorak (the G-1000 material is rather “canvasish”) off and put it in a standing position. It became that stiff. The temperature was then around -35 degrees Celsius. On the pass it was much colder but less humid, so this wasn’t a problem. I guess the situation could be the opposite if the winds or the weather in general changes. Anyhow – if the tent would have been as stiff as my anorak, then I suppose it could have, at a certain point, have strengthen the canvas a bit. Could it could also be the opposite, as you point out – like a stiff wall against the wind. I guess that the stiffness would become worse the longer the group of nine would stay in it – creating humidity. Repairs could certainly fail easier – good point! In fact and just “a shoot in the night” – this could explain the rather straight cuts in the tent (if not most were made by the rescue team). When the canvas was folded and later got stiff – that’s were any breaking point potentially could appear. 

As for leaving the tent – I again think that the gravity wind we are talking about would not let you retrieve things inside the ten that easily. Perhaps some did – like the valenki or perhaps some socks not already on. But considering that they had to act immediately to cover the tent with snow – even this a hopelessly hard scenario – there would be very hard to find things in the dark with not sufficient flashlights in the dark night. It really gets dark here when the moon is not shining, although the snow. To let two or three people crawl inside under the snow whilst the other are waiting would be very hard. It’s not as if you had to stand there waiting. A wind of 25, 30, 35 m/s (?) with an outside temperature of likely -35 Celsius, is not survivable if you don’t act immediately. And by this point I believe they were pretty sure where to try out any survival to wait out the event (further down into the forest). I’m sure they didn’t think that this would go well – but a better option indeed. Remember the Anaris case – they stayed and froze to death. I think that your example of Slobodin only having one boot, is a good indication to the above scenario – grabbing what you see. Your mention of the frozen hands is also an valid point. I would even suggest that their hands and feet were already totally numb on their way down.

Yes, Semyons camera have caused a stir. It could be some sort of conspiracy, yes – but I would rather suggest that he took it with him – either because he already had it on him or because he chose to grab it. After all these are expensive objects and I’m sure Semyons first thought wasn’t that he was going to die, rather afraid of losing it. From two of the photos in his camera there are very faint silhouettes of taiga. This would suggest that the photos were taken inside the forest, either before or after the pitching on Kholat.   

Yes, the autopsy reports are odd – I agree. Regarding the urine levels, I don’t know what to expect – I assume you are right to keep options open for other things than plain hypothermia. Hard one. Coats unzipped and gloves in their pockets are totally in line with the Anaris event. Let’s see if any toxicology and other reports will be available in the now open case. And regarding Semyon and Lyuda, you make a good point. This is actually the most problematic to me. But after taking part of the autopsy report and discussions with people that have studied the report – the case of damages being ante- or postmortem is problematic. I believe the case to be as I wrote briefly in the theory page, regarding Semyon and Lyuda. In this respect I also want to know more about the damages to skin and skulls – if postmortem. We know for example that Lyudas skull must have been badly damages by the search sticks, since part of her body tissue was found before her body. If the search team documented such damages or if it was put aside, I don’t know. Working as an archaeologist, I know though that when we accidently pick through a hidden and beautiful jar or a papyrus, we try to tone such things down. I don’t know if this is a pertinent comparison.

Regarding the den(s) and the cedar and their positions, you raise interesting questions again. These are important facts in order to understand the subsequent events. I would say that, also comparing to the Anaris case and from the survivors account, is that things are not always very rational. We must remember that by the time a fire was made and the dens were excavated, substantial time in the absolute possible weather had passed. It is important to note that as time pass, irrational behavior should be expected. In this instance it might explain peculiarities in decisions. Hypothermia means that the body core temperature sinks below 35 degrees Celsius. This usually gives symptoms of fatigue, impaired coordination ability, confusion and hallucinations. Eventually, apathy usually kicks in. With a body temperature of around 30 degrees Celsius, most become unconscious. Furthermore, it can be debated if the distance between the den and the tree were too distant. You could keep voice contact and likely they started with the fire first and the best digging spot would have been tried out after or concurrently with that – plus that any decision had to be made quickly. Yes, it seems that at least Lyuda and Doroshenko fell from a tree due to their wounded parts in their armpits.

Many thanks for input and sober reflections. I hope my viewpoint was rather clear, albeit with some holes. I too, take my hat off for such great insight in the case and for sharing your experiences!

All the best - Richard

[WAB]

Best forum readers!

I thought that it would be a good idea to post something here, after writing the article about the theory involving a katabatic wind. Me, Andreas, Ekaterina and Artem, made an expedition to the pass in Jan/Feb, which is shortly described together with the new theory. You can find it under “The Swedish-Russian Dyatlov Expedition 2019” on this site’s Home page – or in my constantly updated blog. A link to the latter is found along the article mentioned above. Before commenting, I would suggest that you read the theory in full.

I have tried to build the case out of my own experiences from mountainous areas and by experiencing the Dyatlov pass/Auspiya valley during the same time of the year as the Dyatlov group. I have also compared the Dyatlov event to the Swedish accident of Anaris in 1978. The latter which in many ways mimics the circumstances in the Dyatlov pass - affected by a gravity wind (katabatic wind).

I have experienced many positive feedbacks on the theory, but also much criticism. The latter is very welcomed in order to improve the knowledge of the event. So please, when objecting, try also to explain why you object to details or any larger unfolding event during the evening/night of February 1st in 1959 - involving a possible katabatic wind. This, so that we can build a solid case. To my surprise most of the people objecting to the theory are less favourable of the idea of leaving the tent without giving a thought of staying – this in case of a falling/gravity wind. It is important to solve the “leaving the tent” situation, because it is this specific act that more or less leads to the subsequent events. So let me first make one thing clear. I am not talking about any wind or any storm. The density and gravitational force of a katabatic wind is brutal. A storm would mostly give you the option to dress and to stay/leave the tent under rather controlled forms. Furthermore, never forget the coexisting low temperature, both during the night and the cooling effect of a gravity wind rolling down the gradient. So again, we are not talking about severe winds or a storm of wind speeds up to around 25 m/s, but about possible wind speeds above that. Even though we should be open for wind speeds during a katabatic event of around 20-25 m/s. Remember that the katabatic wind recorded during the Anaris event was “only” around 20 m/s. The cooling effect was then around minus 50 degrees Celsius (-58 degrees Fahrenheit).

Many would argue that the Dyatlov group could have stayed in the tent. But I would argue that crawling back under the snow covered tent, if possible at all due to the conditions involving a gravity wind, wouldn’t have helped them - which they wisely and obviously realized. Yes, the tent would have been better secured with the group inside, but the cooling effect under a gravity wind would eventually have killed them. Furthermore the torn tent was already made unsuitable for this option. In fact - it was exactly this that killed the Anaris group, where the only person escaping the shelter was the only survivor. He was in constant movement and ventured elsewhere, while the rest froze to death.

So, let us start there – and let the ideas, concerns or additional viewpoints flow.

Sincerely,
Richard Holmgren

Dear Richard Holmgren!

Next time back I have read in newspaper “Aftonbladet” article of Katarina Norrgrann ”Därför dog de nio på berget” on February, 08th. Certainly no oneself article, and its copy on the Internet. After that I had an insuperable desire contact to you and discuss some features of your expedition. I have directed e-mail to Katarina with the request to discuss about you travel and to contact you for this purpose. While I have get not answer and good luck smiled to me, that you have written the thoughts on this forum has.

First I should tell that you the big heroes that have perform such travel and have courageously overcome all difficulties. In addition it is necessary I tell to you, that from many other things have passed route part in difference strictly on route Dyatlov group. That not do many modern groups. They go on easier way – snowmobile track on old Mansi`s road. I know that I speak about it because we (with my friend Alexander Alekseenkov) have already made 4 similar winter travel exclusively with the research purposes on these subjects.

Now we plan the fifth travel, therefore we have only small time for preliminary discussion. It is possible only till March, 01st 2019. When we will come back, I will inform on it at this forum.
At first I would like tell some words under your theory.

1.I almost completely agree with your estimations about trajectory of studying of this theory, in particular, that the basic dominant of this failure is the reason of escape from tent, however do not consider to you, that the wind without additional physical factors could be the reason only. They perfectly understood (if they were in full human intellect) that the similar way leave therefrom is equivalent as jump out of the plane if it flies at the big height, however is the fact that they so have made it. From here it is possible draw conclusion that they did not make decisions agree to logic and to full human intellect. Means there was external influence on their human intellect.

2.I have very big doubts that in this case we have Katabatic wind because it is characteristic for the stream of very cold air falling with plateau downwards and filling all space below. Here we have picture slightly another. The ridge of the Ural mountains is divider of two climatic zones: warmer which is formed under the influence of warm current Gulf Stream and (on the opposite side) colder - which is available beyond Ural Mountains and it is formed under the influence of the Arctic cold which comes from space behind islands Novaya Zemlya (New Lands). This big difference of temperatures also forms strong wind which pass through the Ural ridge. In addition the increase in speed of wind is reached at the expense of the effect reflected in the Bernoulli law, which is caused compression ground borderline stream by Ural ridge. Thus the valleys located in the West in addition develop air stream in direction from the West to East. Dyatlov`s group Tent was in 1 to 2 km from watershed line of the Main Ural ridge, therefore it was under the influence of warmer air from the West, than all lowland to the East away from mountains Ural Mountains. It means that warmer air covered East zone of cold area and not could go down far downwards because it had smaller density, than the bottom colder air. It turns out so that below was cold, but almost windless weather, and above, moderate or rather strong wind, but much warmer.

3.You almost truly and precisely estimate influence of weather conditions, only (as I think) overestimate severity of these conditions during the beginning and continuation of all actions  little. By my estimations (method of interpolation of weather on the basis of 7 surrounding meteorological stations: Troitsty-Pechorsk; Syktyvkar; Niaksimvol; Burmatovo; Ivdel and Chardyn) I have ascertain that weather should be (presumably) such: tо at tent place ~-12 …-18C; speed of wind at level of top N-E spur from mountain “1096” (now - Holatchahl) ~ 15. 18 m/s; tо at cedar ~-22 …-25C speed of wind in this area - insignificant. During expedition in January 2015 we have found out that at a wind 15 … 16 m/s at tent place, on half of way to cedar, the wind abates practically to the indiscernible. It is possible to look at some video fragments under the reference:
https://drive.google.com/drive/folders/16JAL1OWeJ6X7Prm8F8l1FbwyWcsXQFjQ?usp=sharing
On these video you can see all way from place of tent to cedar and wind changes wind velocity.
This video by which I did in way from tent place to cedar. Unfortunately there all comments in Russian but if it is necessary it can be seen by means of the translator.
The initial information I took on a site of the World Meteorological organisation ftp://ftp.ncdc.noaa.gov/pub/data/gsod/  about those points where there was data for 4 adjacent days since the beginning of events
I regret that I do not have time now to alter the scheme in English.
If there is a necessity, I can give the reference to the big article about weather to this place and its separate special cases. But it is in Russian too. 
It is possible use computer translation program.
I can offer only that, I will answer if it probably in more details all questions, but only after returning from our expedition.
I can suggest look at some supervision of wind In January, 2015 under this reference:


4.Unfortunately I have not found the description of case Anaris group in the Internet, therefore I cannot compare it to conditions in which there was Dyatlov group. If you send me the reference to this description in English, German, French or Spanish (at me the translator is adjusted only on these languages) that I will be very grateful to you.

5.I think that it is not necessary consider case returning of participants  Dyatlov group to tent from a cedar because very many details say that it was generated then (1959) belief of participants of search because they could not explain their arrangement in space and in time on course of events. It is a separate part of discussion which should be conducted only after we can understand conditions of weather and the reason escape from tents. As last resort it can be received in Swedish, but I should search long time for adequate translation possibility. If built in Google-translator cannot make it.

6.I do not want tell that bad, but after viewing your photos arrangement of place you tent, at me the impression is made that your tent stood minimum in 200 … 300 metres from that place which has been calculated with the big accuracy, several Russian researchers. I want notice that you were the third group which during last current 60 years has organised winter parking place in night in this local area.
Dyatlov group in 1959 was the first.
The second is team by Alex Markov's group from Ekaterinburg (university UPI) in 1999, in time expeditions to honour of the 30 anniversary of events Dyatlov group.
The third group was yours. 
It is everything, not including ours (with Alexander Alekseenkov) four series for 5 … 6 spending the night in area about rocks. This place has been chosen by us specially, proceeding their my hypothesis of events. But it should be discussed later.
I have forgotten tell that in the same place there was group of professional rescuers in 2013 which has arrived there by the helicopter and provided departure there for one day of correspondents of the newspaper «Komsomolskya Pravda» which much write about " Dyatlov pass " on it theme. We have come there 4 days prior to them, and did not foreknow that they there will be.
On your photos there are no exact reference points, therefore for understanding how much I am right in the estimations, I would like to ask you give me co-ordinates your tent on slope that it would be possible compare to available calculations and comparisons on photo 1959 and our, as modern. If it is the confidential information for public means that it is not obligatory. Or this information can be send to my e-mail or in the personal messag in that forum. I will not publish in open sources. It is for you only

7.I very much liked your photos on their quality and art characteristics. You could inform me what cameras and objectives you used, what I could compare to our modest possibilities?

8.I Ask my admiration and respect to Andreas because I understand, what big case you have made in these researches.

            Regards
                                Vladimir A. Borzenkov.
                     PhD (aeronautics and space engineering)
                                        Moscow, Russia.

[Monika]

Hello, Richard

Your article is very interesting to me. The facts are written in a clear and logical manner. I have to say that his explanation of the sequence of events is convincing. Yes, I can imagine this cause of the whole event. There are several inconsistencies, but they are not so serious and can be probably  explained.
For me there are new findings and some doubtful points:

“With the extremely low temperatures at hand, their socks would not immediately turn wet as long as they moved quickly to the forest to seek a temporary shelter”.
“Many would argue that fleeing from the tent and warm equipment in such conditions would mean certain death. In line with their outdoor experiences I'm sure they knew that such winds were unfortunate and rare but hopefully they would not last all night. Their tent, if still in place, would be within grasp as long as they stayed alive elsewhere”.
- yes, it might eventually explain why they went to the forest without shoes and warm clothes.
It has never occurred to me to take into consideration that in a strong wind it is difficult to get dressed and take shoes when wind knocks you to the ground.
What, however, does not quite fit with this theory is that the tent eventually resisted the wind, and the escape from it into the forest was eventually unnecessary. But probably they did not know it, and they feared the tent would collapse. And at the same time, they could plan to return from the forest in a short time when wind will calm down. This theory explains well the flashlight left on the roof of the tent. It is true that the tent has not finally fallen. But in that whirlwind, the darkness and the hum, they could get panic and be afraid that the tent would collapse. That's why they made a tragic evil decision and went to the forest  with the wind behind them, thinking that the wind would soften for a short time (maybe their previous experiences). And walk a mile away takes does not take much time for trained peoples (up to 25 min). For me, in this situation inexperience and revaluation of own strength and determination due to their young has played a role .

“While Doroshenko and Krivonischenko took responsibility for making a fire, the others started to dig out two bivouacs”
-  I do not understand why two bivouacs have to be built and not only big one. And more people next to each other would be better warmed up.

“The rest of the team, Slobodin, Dytlov and Kolmogorova never settled in the nearby bivouac for long – that is, in the bivouac that was retrieved empty in May and still prepared with branches of fir. Perhaps the chocking experience of this potential death trap, collapsing over their friends and with insufficient strength to help out, gave them only one last option - that of trying to get back to the tent”.
 - I can imagine such a culmination of the whole sequence of the event.

Since I was convinced all the time that the whole event had caused some physical phenomenon, I really enjoy this latest theory by Richard, although the theory of plasmoid lighting balls (https://sites.google.com/site/mezoelectric/dyatlov-pass-incident-1) is also quite plausible.
I like the fact that, unlike us, Richard has an experience of camping in a hostile environment. Therefore, I do not completely reject his theory. Certainly his theory is more convincing for me than theory of rocket testing / killer army / aliens .

[ARCDOC]

Best Vladimir A. Borzenkov,

Thanks for your many interesting details and insightful considerations! Very well put and with great precision. If you have time to talk over Skype or anything similar, contact me from my homepage. I feel that I have many commitments going on and writing answers to all questions and claims in a fruitful way, takes a lot of effort - as I have already tried to do elsewhere. This forum is just one place "bombarding" me at the moment and other commitments needs to be fulfilled too. I suggest that you contact me as above and I will then also write a summary on anything coming out from our discussion, and put it in this thread - so that many more continuously can take part. Sounds good?

Sincerely,
Richard

[WAB]

Best Vladimir A. Borzenkov,

Thanks for your many interesting details and insightful considerations! Very well put and with great precision. If you have time to talk over Skype or anything similar, contact me from my homepage. I feel that I have many commitments going on and writing answers to all questions and claims in a fruitful way, takes a lot of effort - as I have already tried to do elsewhere. This forum is just one place "bombarding" me at the moment and other commitments needs to be fulfilled too. I suggest that you contact me as above and I will then also write a summary on anything coming out from our discussion, and put it in this thread - so that many more continuously can take part. Sounds good?

Sincerely,
Richard

Dear Richard!

I want offer the following order of our joint actions:

As now from you it is required many comment from other readers, we will make delay before our returning from Dyatlov pass (it approximately on March, 15th) and after that we will discuss other questions. Many participants of discussions in this time will calm down. And I will have new facts and the new information.
I will write the e-mail to you in the personal message at this forum.
If you not against let's operate so?

               Sincerely,
                                         Vladimir

[WAB]

Richard has already answered you, but I will offer the alternative version of these answers …

Have also posted this on the other thread.

I have just read the whole theory.  It's very interesting.  I like that it provides an explanation for the flashlight being found on 10cm of snow on top of the tent.  This has been a detail I have been thinking about.  There are other possible explanations for this, but I think Richard's is a good one.

The theory kind of reminds me of the movie "The Day After Tomorrow", where cold air is drawn down from the upper Troposphere and freezes everything instantly.  Obviously the movie is just fiction, but I suppose a significant downdraft of cold wind is credible on Kholat Syakhl.

This film does not correspond to natural processes. It is interesting as emotion, but it is not necessary for the analysis of the given event.

Let's consider the tent.  It was two tents sewn together and had many makeshift repairs, which means it probably wasn't fit for high winds.  Also, if the temperature suddenly dropped to below -50C could this affect the material of the tent?  I am not an expert of fabrics but most materials become embrittled at very low temperatures.  I would not be surprised if the fabric became stiff and therefore the repairs more likely to fail.

1.The Temperature did not fall to-50С.
2.The tent Fabric is a canvas (cotton very rough fabric) which is good preserve at low temperatures. Even at-50С. One time we met New year in wood at such temperature, and our canvas tent has well remained.

If the tent suddently failed due to high winds and low temperatures it would have put the team in a very dangerous position.  I think what Richard is saying is that they didn't leave the safety of they tent.  Instead, the tent was nor longer a safe place so they had to leave to find somewhere safer.  It's a credible scenario.

Richard is rights in this sense. The tent allowed them to concentrate warmly locally, therefore they could spend night safely. And two its companions have in the same way spent some spending the night to previous year Igor Dyatlov be in Subpolar Ural Mountains when they waited when connection of their group which went from two different places was possible.
In case of powerful damage of tent they got to catastrophic position. In case of powerful damage of tent they got to catastrophic position. Especially if to consider that condition of clothes in which they have left tent. In such position they did not have more safe place, considering that without presence of skis they could not leave far in wood where there is fire wood suitable for the big fire.

However, there are things that need to be considered in detail:

If the group had time to walk a mile down the slope, they should have had time to retrieve their footwear from the tent and some better outdoor gear?  Slobodin at least had time to put one of his boots on, so why not the other.  If the events happened suddenly, then their hands would not have been too frozen to put on their boots and collect essential equipment.

These are correct remarks, but it again leads to logic fork: Or they meaningly went to suicide or they were in a deranged condition when escape of tent. The first is absurdity. If I not correctly speak, I ask to prove the objections.

Why did Semyon have his camera around his neck?  Was it just a coincidence or was he taking photos just before the events began. 

It is very simple question: he did not remove his camera after they have come on this camp.
There is real suspicion that it has given his camera to people in tent, and it still had only empty case from camera.

Semyon and Thibo were probably on duty being betters dressed, or maybe they had gone outside to relieve themselves.

Yes, this very correct remark.

The autopsy reports are odd.  There are peculiarities around the cause of death of the group.  Dorishenko's Edema, urine levels inconsistent with freezing to death. 

Here it is impossible to consider all only in one plate. It is necessary to do it separately and very carefully.
1.At Doroshenko was not a hypostasis, and presence what that of a foamy liquid in a place about a mouth. It happens at defrosting of bodies, especially if is not clear as they transported also what substances could get after death on a body. In addition it is necessary to specify that in the same line of the description of a body coroner has written: «In the field of a red border of an upper lip there (is) a hemorrhage of dark red colour in the size 1,5 х 2 sm (0.6 х 0.8 in)» (c)
It is literal translation from Russian. In brackets for this purpose that it would be possible to understand my comments is easier taking into account semantics of Russian.
2.Urine Level is not indicator because medical researches on cold in a current of long time among actively moving groups do not exist. In our (Russian) forums medic doctors speak that after hit in cold diarrhea process begins, but they do not know (under not clear to me reasons) that after 3 or 4 days on frost return process when the human body keeps a moisture, for reduction of losses of heat begins. For those who participated in long winter independent expeditions, these supervision are not news.

Coats unzipped, gloves in pockets. 

In it too there is nothing surprising. People continued move (or fill catastrophic losses of heat from a cold) until muscles normally could work for them. If after stop (for weariness, for example) they could not force to work themselves further they any more did not pay attention to clothes condition. At them does not remain forces and muscle lost tone for work.

The two Yuris had a fire going that burned for an estimated 1.5 hours.  Why did they die? 

It is result of thermal relaxation. That is reactions of brain to heat, after the big and difficult work on cold when the human starts feel heat first signs. If the human in such condition bring to warm premise, that he runs into non-existence. Such cases it was observed much when it was possible help freezing about cities and settlements.

No toxicology report in case files? Why?  Has just got lost over time?

If in case there was mention that alcohol what that the analysis was is not found out in them. Toxicology could find out even faster, than alcohol. Means toxins or was not or their level was small (for example from use of medicines). The reason for the detailed toxicological analysis is Anyway necessary. And it start think out already in field of 50 and more years later.

The chest injuries - consistent with a sudden and fast impact, such as falling 5m to 7m. 

Falling should be not obligatory strictly vertical. Also any another if they moved without stop there will suffice.

Equivalent to about 2 to 2.7 tonnes of force.

It is incorrect estimation, because:
1.To start process of crises edges in this case it is necessary have initial effort approximately 1 ton (1000 kg of force, or 10000 N).
2.Process in this case is dynamic, therefore all depends on speed of increase of loading. Crises can begin even if this time will slightly exceed 2 milliseconds. And the further process depends only on stock of energy which is involved in this process.

Could a collapsing snow den cause these injuries?

No. At least because in friable snow by which ravine walls in January and February are covered, it is impossible to dig a den. Besides, there are snow stocks is small on thickness.

Luda had a smashed nose, and a large bruise on femur. 

It is Zina, bat no Luda… 
The slope is slippery also exists set of stones available, therefore it would be surprising, if she did not have any damages and it would be in this place.

Semyon had a large cut on the right side of his head, exposing the skull, ( the same side as his crushed ribs). 

This is consequence of different factors which have converged on one party. On a head the cut, and result of decomposition of fabrics of the person is located not at thawing of the frozen body. Probably, you use not the most good translator.

Injuries still seem more likely to be from a fall than collapsed snow den to me.

In it you are absolutely right. I tell it because itself professionally was engaged in biomechanics of shock processes on a body of the person.

Why set up two separate areas: 1. The cedar and fire. 2. The ravine and snow den. 

Probably because there is no fire wood for fire. Unique suitable fire wood was at cedar, and is even more exact - on the cedar itself. But them was very little. Other suitable fire wood was not in environment. Pass further to wood they could not, because the zone of deep snow began where it was impossible pass without skis.

Why not build a fire near the snow den?  In my mind one possible reason for doing this is that some of the team had already sustained significant injuries.  Maybe they fell from the tree or fell in the ravine and therefore a shelter had to be built for their survival.

That it is possible to name shelter (den), is only few trunks of fir and one birch. It could be used only as time platform for resocks of bodies, for example, to fire place under cedar. Other utilitarian appointment to this device it is impossible find. Because it almost can serve nothing.

I like the explanation for the injuries of Dorishenko.  The armpit scratches etc.  I too also think that the two Yuris got these either trying to climb up or down the cedar with frozen extremities.  It seems the most likely place to get the minor scratches and abrasions.

Yes, of course, this very competent thought.

All in all I think it's an interesting theory, particularly as a reason for leaving the tent and the camp and it warrants further consideration.

I take my hat off to you for retracing their steps to gain a further insight into the incident.

I (with pleasure) join such estimation of activity Richard and Andreas.

[WAB]

I see two weaknesses for the katabatic wind theory:
...........................

It is pity that I do not have today time for the answer more. If you not have smth agains, I answer next time

[Star man]

Thank you Richard and thank you WAB for your responses to my post.

Again the details always seem to raise more questions.

Good luck on your trip WAB.  Safe journey to you.

 Are you going to try and take equipment to measure infrasound?

Richard,  I like your theory.  Maybe the topography and conditions there are not perfect to create katabatic  winds easily.  I still think it should be investigated further.  Even some kind of freak localised storm may explain what happened.  Basically, any natural event that could have caused severe damage to the tent. 

It might be interesting to understand the forces on the tent due to various wind speeds.  I will have a look at this when I get some time.

Regards

star man

[sarapuk]

Have also posted this on the other thread.
Let's consider the tent.  It was two tents sewn together and had many makeshift repairs, which means it probably wasn't fit for high winds.  Also, if the temperature suddenly dropped to below -50C could this affect the material of the tent?  I am not an expert of fabrics but most materials become embrittled at very low temperatures.  I would not be surprised if the fabric became stiff and therefore the repairs more likely to fail.
If the tent suddently failed due to high winds and low temperatures it would have put the team in a very dangerous position.  I think what Richard is saying is that they didn't leave the safety of they tent.  Instead, the tent was nor longer a safe place so they had to leave to find somewhere safer.  It's a credible scenario.
All in all I think it's an interesting theory, particularly as a reason for leaving the tent and the camp and it warrants further consideration.




But the Dyatlov Group were experienced outdoors people. They would have known that the area that they were going to was known for very strong winds. They were hardly likely to have risked  their lives if they didnt think that the Tent was strong enough. If they left the Tent in those weather conditions and probably at night then its obvious that they thought the Tent wasnt a safe place to be. 

[sarapuk]

Iam surprised at the amount of words being used to try and make a case for a wind that is described as Katabatic.  Katabatic sounds an impressive word. But that doesnt alter the fact that its just another wind. And all accounts show that wind is not a plausible explanation for the Dyatlov Group leaving the Tent and the subsequent events.

[Star man]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

[sarapuk]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Thats an impressive looking calculation. But how do we know what the actual speed of the wind was when the Dyatlov group were on the mountainside  !  ?  And for that calculation to be of any use we would also need to know the strength of the Tent FABRIC, and where any joins in the fabric were. 

[Star man]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Thats an impressive looking calculation. But how do we know what the actual speed of the wind was when the Dyatlov group were on the mountainside  !  ?  And for that calculation to be of any use we would also need to know the strength of the Tent FABRIC, and where any joins in the fabric were.

The call is only to allow a somewhat better judgment of the high wind theory. It doesn’t take account of a gusting wind which could have shaken the tent.  But even for a high wind the forces are still survivable.  In my mind a 100 mph wind should be enough to rip up an empty tent and blow it away. But it doesn’t look like it would destroy the tent with 9 people in it.  Obviously it is unlikely the wind speed actually reached 100 mph but I am using 100 mph as an upper reference guide.  Only a reconsideration could give a more reasonable answer.

I like to try to understand how any given theory can be positively proven or disproven given the lack of concrete evidence for the DPI

[sarapuk]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Thats an impressive looking calculation. But how do we know what the actual speed of the wind was when the Dyatlov group were on the mountainside  !  ?  And for that calculation to be of any use we would also need to know the strength of the Tent FABRIC, and where any joins in the fabric were.

The call is only to allow a somewhat better judgment of the high wind theory. It doesn’t take account of a gusting wind which could have shaken the tent.  But even for a high wind the forces are still survivable.  In my mind a 100 mph wind should be enough to rip up an empty tent and blow it away. But it doesn’t look like it would destroy the tent with 9 people in it.  Obviously it is unlikely the wind speed actually reached 100 mph but I am using 100 mph as an upper reference guide.  Only a reconsideration could give a more reasonable answer.

I like to try to understand how any given theory can be positively proven or disproven given the lack of concrete evidence for the DPI

A KATABATIC WIND can reach 200 MPH, or hurricane force. And as you correctly say , even for high wind the forces are still survivable. The Dyatlov Tent doesnt appear to have suffered such high forces, making it even less likely that wind played a part in their leaving the Tent.

[Star man]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Thats an impressive looking calculation. But how do we know what the actual speed of the wind was when the Dyatlov group were on the mountainside  !  ?  And for that calculation to be of any use we would also need to know the strength of the Tent FABRIC, and where any joins in the fabric were.

The call is only to allow a somewhat better judgment of the high wind theory. It doesn’t take account of a gusting wind which could have shaken the tent.  But even for a high wind the forces are still survivable.  In my mind a 100 mph wind should be enough to rip up an empty tent and blow it away. But it doesn’t look like it would destroy the tent with 9 people in it.  Obviously it is unlikely the wind speed actually reached 100 mph but I am using 100 mph as an upper reference guide.  Only a reconsideration could give a more reasonable answer.

I like to try to understand how any given theory can be positively proven or disproven given the lack of concrete evidence for the DPI

A KATABATIC WIND can reach 200 MPH, or hurricane force. And as you correctly say , even for high wind the forces are still survivable. The Dyatlov Tent doesnt appear to have suffered such high forces, making it even less likely that wind played a part in their leaving the Tent.

At 150 mph the force on the tent would have been 2200kg, and at 200 mph the force would have been 3900 Kg

I doubt that any of the tent would have still been standing if it had been exposed to those sorts of wind speeds.  I doubt that a katabatic wind of that magnitude would occur 300 metres from the sumit.

Saying that a lesser wind may still be able to tear open a poorly repaired tent.

If a katabatic wind had developed it would have flowed down into the valley below in the direction that the group went.  If the wind speed was significant it should have up rooted some trees and it would not have been easy to have built the fire at the cedar.  I don't believe there was any evidence of fallen trees when the search and rescue team arrived.  So overall it is looking less likely, but difficult to rule out completely.  To support the theory we would need to identify some way of positively confirming that high winds capable of damaging the tent were there that night.  The cuts in the tent seem to be made by both tears and cuts with a sharp implement and as we know these could have been made during the tents recovery.

[WAB]

Thank you Richard and thank you WAB for your responses to my post.

Again the details always seem to raise more questions.

It is quite normal situation. It is so be always.

Good luck on your trip WAB.  Safe journey to you.

Thanks! We very much will try! 
As well as in all four previous expeditions … 

Are you going to try and take equipment to measure infrasound?

It is very painful question for me … Even simply good measuring instrument of noise (or noisemeter) costs not less Э2000 (Euro …. Or ~ $2500 that the same, and for me it is unreal). Therefore I try be use only the appendix to the smart phone in form of program. I understand that it is completely not professional device, but I do not have choice …
There it is possible receive even some spectrograms and almost in the necessary range, but ….
So I need do only that turns out, instead of that I very much would want. Even if it is not absolutely that is most good.

It might be interesting to understand the forces on the tent due to various wind speeds.  I will have a look at this when I get some time.

It will be interesting for reading …

Regards

star man

With not smaller (it is big) respect

                                              WAB

[WAB]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Dear Star man!
I will a little specify your calculations.
At first I will copy yours formula how it is accepted in aerodynamics (your formula correct, but little less detailed for understanding):

Fresist = Cx* ro*V²* S/2

Where it is designated
Сх – it is the same as at you Сd = factor of front resistance (without units),
ro - here it is necessary write in Greek letter «ro», but I do not have it in my computer alphabet and I write its in Latin (it is measure kg/m³),
V - speed of stream if it laminar also is absent interface layer(it is measure m/s),
S - the area of cross-section size, just as at you Ax (it is measure м²)
Now we take more real values of the sizes entering into this formula:
1.   Cx - for tent it is necessary take that here such:
 


Lilac colour is designates interface layer, but I will tell about it later.
Therefore Cx cannot be = 1,4 in any way.
For Cube the party directly Cx =
 


The right extreme column – it is the settlement value, the second on the right - experimental measurements.

For Cube an edge to air stream Cx =
 


For Hemisphere the basis to air stream Cx =
 


It will be the maximum value though on experiment in colder conditions for Hemisphere the basis to air stream it was equal Cx = 1,44.
Therefore Cx it is necessary to take = between Cx = Cube the party directly and Cx = Cube an edge to air stream, or between 1,05 and 0,8. We take Cx =0,95. It will be the maximum approach to reality. It is will be dimensionless size.

2.ro – it is air density at the given height from earth level. I do not know whence you took value of density, but for earth level at tо = + 15^оС it will be = 1,22 kg/m³, and for height in 1000 m and at tо =-10^oC it will be = 1,112 kg/m³
3.V – it is speed of stream. You have 2 values, therefore for 80 mph V = 35,76 m/s, and for 100 mph V = 44,7 m/s
4.S – it is the area. For tent in our case we take on the maximum value, taking into account that the tent has partially been driven in slope as 4 m (it is length) of *1,3 m (it is height taking into account the driven part) = 5,2 м².
The scheme of the driven tent is:



The tent has not been dug completely. It is not meaningful, and it will be worse for people because it will fall asleep more snow.
Preparation of the same platform in accuracy for tent, video which is made on that place where the tent placed in 1959 is shown on it:

https://drive.google.com/file/d/0B6J-XIhYsx39ZWlHOXkwZmVVbjg/view?usp=sharing   

after that the same, platform as it has been made and at Dyatlov group in 1959 (for this purpose has been levelled that the tent bottom would be on more flat place).
These are our experiments in the winter 2014. The temperature was-21…-22^o C, the wind was small, approximately as 5 … 7 m/s, “Shura” (Alesander Alekseenkov) has been dressed approximately how many participants of Dyatlov group after have escaped from tent. It was the illustration of possible working capacity of these people below, after place where Zina has been found, but without that they have taken place to this place in the conditions of snowstorm at wind nearby V = 15 … 18 m/s (or approximately 35 pmh).

If made out calculation for these values for 80 mph force of pressure on tent = 3512,34 Н or 358 kgF (forces) turns out, and for 100 mph force of a pressure on tent = 4390,42 Н or 447,54 kgF (forces) turns out.
That "mute" does not coincide with your calculations … 

The resume:
- Pressure will be even less because there will be its losses on an interface;
- area of section of tent will be less because is sagging;
 - fabric cannot be absolutely rigid; the tent costs not exactly on perpendicular to stream and е. с …
Therefore it is possible draw conclusion, what not loading on tent because of wind was the main reason of that they have escaped from tent …
The reason here exists internal and it is connected with psychology as all participants and group as whole.

[WAB]

......................................

A KATABATIC WIND can reach 200 MPH, or hurricane force. And as you correctly say , even for high wind the forces are still survivable. The Dyatlov Tent doesnt appear to have suffered such high forces, making it even less likely that wind played a part in their leaving the Tent.

I do not think that were such wind. Because I had possibility feel on myself wind approximately 50 m/s. At such wind, even on flat part of the earth, the man cannot keep vertical position. Even if he bears backpack with the big weight and small resistance to wind. Certainly, their tent at such wind could not keep the form. However it was steady. In 2014 we have made experiment with similar tent on its stability to wind. But today I cannot write any more (at us 3 o'clock in the morning). Next time I will try to show photo with this tent in one day, in 4 days, in 2 weeks and in 3 or 4 weeks. It not we photographed all last photos …

[Star man]

I have completed some simple calculations of wind force on the tent.  I have used a formular that is used to estimate the wind loading on civil structures.  I had broken it down into detail, but for some reason all my text has just vanished so here is the simple version:

F= AxPxCd

A is cross sectional area normal to wind direction
P is the wind pressure = 0.613 x V^2. V is I metres per second
Cd is the drag coefficient which is about 1.4 for a smallish rectangle

At 100 miles per hour the force on the tent would be about 870kg
At 80 miles per hour it would be about 620 Kg

Most of this force would be spread out across th fabric on the side exposed to the wind and also taken up by the tension in the rope and then transmitted to the supports that the rope is attached to.

All in all it doesn't seem that significant.  For 100 miles per hour it may have been approaching the limit for the rope but probably not for the tent fabric.  If there was a weak point (tears) on the fabric this may have concentrated the force at the corners of these tears causing the material to tear further.  It's difficult to say though.  The tent supports may have been pulled, but I believe these were still standing when the tent was found.  Was the rope still in one piece?

Overall I don't think it looks like it would support the High wind theory.  Obviously a reconstruction of the tent in a wind tunnel would be a better test.  Does anyone have a wind tunnel available to test the hypothesis?

Regards

Star man

Dear Star man!
I will a little specify your calculations.
At first I will copy yours formula how it is accepted in aerodynamics (your formula correct, but little less detailed for understanding):

Fresist = Cx* ro*V²* S/2

Where it is designated
Сх – it is the same as at you Сd = factor of front resistance (without units),
ro - here it is necessary write in Greek letter «ro», but I do not have it in my computer alphabet and I write its in Latin (it is measure kg/m³),
V - speed of stream if it laminar also is absent interface layer(it is measure m/s),
S - the area of cross-section size, just as at you Ax (it is measure м²)
Now we take more real values of the sizes entering into this formula:
1.   Cx - for tent it is necessary take that here such:
 


Lilac colour is designates interface layer, but I will tell about it later.
Therefore Cx cannot be = 1,4 in any way.
For Cube the party directly Cx =
 


The right extreme column – it is the settlement value, the second on the right - experimental measurements.

For Cube an edge to air stream Cx =
 


For Hemisphere the basis to air stream Cx =
 


It will be the maximum value though on experiment in colder conditions for Hemisphere the basis to air stream it was equal Cx = 1,44.
Therefore Cx it is necessary to take = between Cx = Cube the party directly and Cx = Cube an edge to air stream, or between 1,05 and 0,8. We take Cx =0,95. It will be the maximum approach to reality. It is will be dimensionless size.

2.ro – it is air density at the given height from earth level. I do not know whence you took value of density, but for earth level at tо = + 15^оС it will be = 1,22 kg/m³, and for height in 1000 m and at tо =-10^oC it will be = 1,112 kg/m³
3.V – it is speed of stream. You have 2 values, therefore for 80 mph V = 35,76 m/s, and for 100 mph V = 44,7 m/s
4.S – it is the area. For tent in our case we take on the maximum value, taking into account that the tent has partially been driven in slope as 4 m (it is length) of *1,3 m (it is height taking into account the driven part) = 5,2 м².
The scheme of the driven tent is:

The tent has not been dug completely. It is not meaningful, and it will be worse for people because it will fall asleep more snow.
Preparation of the same platform in accuracy for tent, video which is made on that place where the tent placed in 1959 is shown on it:

https://drive.google.com/file/d/0B6J-XIhYsx39ZWlHOXkwZmVVbjg/view?usp=sharing   

after that the same, platform as it has been made and at Dyatlov group in 1959 (for this purpose has been levelled that the tent bottom would be on more flat place).
These are our experiments in the winter 2014. The temperature was-21…-22^o C, the wind was small, approximately as 5 … 7 m/s, “Shura” (Alesander Alekseenkov) has been dressed approximately how many participants of Dyatlov group after have escaped from tent. It was the illustration of possible working capacity of these people below, after place where Zina has been found, but without that they have taken place to this place in the conditions of snowstorm at wind nearby V = 15 … 18 m/s (or approximately 35 pmh).

If made out calculation for these values for 80 mph force of pressure on tent = 3512,34 Н or 358 kgF (forces) turns out, and for 100 mph force of a pressure on tent = 4390,42 Н or 447,54 kgF (forces) turns out.
That "mute" does not coincide with your calculations … 

The resume:
- Pressure will be even less because there will be its losses on an interface;
- area of section of tent will be less because is sagging;
 - fabric cannot be absolutely rigid; the tent costs not exactly on perpendicular to stream and е. с …
Therefore it is possible draw conclusion, what not loading on tent because of wind was the main reason of that they have escaped from tent …
The reason here exists internal and it is connected with psychology as all participants and group as whole.

Thanks for presenting the more detailed calculation. I am sure it is more accurate. 

I used a simple formula to gain a rough idea of the forces and the Cd value is a very rough alignment.  I am familiar with the fluid dynamics but was just looking for something simple to understand the credibility of the theory.  I think with the same conclusion.

Regards
Star man

[WAB]

...............................


Thanks for presenting the more detailed calculation. I am sure it is more accurate. 

I am grateful to you that you have not taken offence to my specification, sometimes at forums it understand as desire wound the opponent. I wanted approach understanding of this question to the validity only. Aerodynamics one of components of my speciality.
And I once again am grateful to you that I could look at that I have written earlier. One picture There was gone. It is the scheme of installation of tent on a slope. Here it is image:



Probably I have forgotten insert the reference to it because there were already 2 or 3 o'clock in the night.
I will try insert it into the initial text if still probably edit it.

  I think with the same conclusion.

It is clear, if people aspire to the end result and at them the understanding is in one channel they will come to the same conclusion.
Planes which develop under the same tasks in the different countries are similar absolutely. Because physics laws are identical in all countries.

Regards
Star man

I too yours Regards .

                             WAB

PS. I have glanced here only for some minutes, therefore I cannot write anything till March, 15th or later.

[Star man]

...............................


Thanks for presenting the more detailed calculation. I am sure it is more accurate. 

I am grateful to you that you have not taken offence to my specification, sometimes at forums it understand as desire wound the opponent. I wanted approach understanding of this question to the validity only. Aerodynamics one of components of my speciality.
And I once again am grateful to you that I could look at that I have written earlier. One picture There was gone. It is the scheme of installation of tent on a slope. Here it is image:



Probably I have forgotten insert the reference to it because there were already 2 or 3 o'clock in the night.
I will try insert it into the initial text if still probably edit it.

  I think with the same conclusion.

It is clear, if people aspire to the end result and at them the understanding is in one channel they will come to the same conclusion.
Planes which develop under the same tasks in the different countries are similar absolutely. Because physics laws are identical in all countries.

Regards
Star man

I too yours Regards .

                             WAB
PS. I have glanced here only for some minutes, therefore I cannot write anything till March, 15th or later.

Hi WAB,

Of course you did not offend me.  I fully understand the nature and limitation of the calculation I made and can easily see that you have used more detailed approach.  When looking at a problem I often start off using "rule of thumb" techniques especially when the result I am looking for is not of critical importance and a simple calculation gives me a reasonable figure to make a judgement with.  It's good that you can bring your skills to help solve this mystery.

Regards

Star man

[Ehtnisba]

Hello everyone ,
I am an old member of the facebook group, but this is my first time writting here. I decided to finally write here and exacrly in this topoc,because this is where I have a personal experience. And when I first read about Dyatlov Pass and tried to compare it to my own experience my first thought was that extreme cold could cause panick in a way they really could have abandon their tent. But let me explain I support the theory only about hy they have left thw tent. Ravine 4 are really a mistery. But..... If we assume their body damages are POST mortem then they are not...
I will not write more about Dyatlov group. I will try to present my experience in similar situations and also only the experience of when me and my friends were in our early 20s.
My father is a mountaineer and I was on ski since the age of 3. The mountain near my home city is not very high (2025m) ,but is famous for its bad weather, and the said strong downhill winds. Let's say I have been there every weekend from December til May for more then 20 years.
These winds are strong,yes. And by strong I mean they are possible to turn you on the ground. In that said mountain there are even cases of turned trees ,but very rare. The point is I  familiar with their sound,strength ,coldness etc... I know that a tent layed down the slope will resist them ,because it is low and these winds act mostly in vicinity. But... This is easy to be said in theory and in day light and in normal situation. What happened once to me and my friends is to show me that in reality people react differently in spite of knowledge and yes sounds of winds and dark and cold CAN effect your reason.
10 years ago me and two guys were up there to ski in fresh snow . It was almost spring and the weather was relatively warm so we wanted to sleep in our tent and catch more fresh snow in the morning. Our tent was in a forest . At about 12 am temperatures dropped , and because we were half asleep probably 2-3 hours passed without us realising that we are actually freezing . By freezing I mean, fingers already numb, speech is hard to be maintained,severe shaking. Imagine waking up in such state. You are already in a bad shape and what you realise is that tent is NOT safe place,because you cannot move to slow down the freezing. Our fingers were so numb we couldn't zip our jackets or unzip the tent. The fingers were numb and twisting like there were no bones and muscles in them. So,even though all of us knew the mountain,knew we are just 40 mins ride from nearest city and even a forest hut was nearby, we were in panic. We couldn't even open the tent,we knew if we stay we may not die,but for sure our limbs would be damaged. So what we did was very similar to what Dyatlov tent looked like. We teared the canvas with lighter - modern tents are polyester I think, so the fire of the lighter melted the fabric and then from the melted holes just stretched the holes with our elbows and bodies. Shoes were impossible to be put on without working fingers . We were well and with no severe frost bite,just because there was a hut with people and fire just 100-200m away. I don't know if there wasn't a hut nearby,if we would have escaped the tent too. I suppose yes, we would have done it and  maybe die or not,but in this situation staying IN the tent was = sertain freezing if not to death to loosing limbs. And in such state you don't think clear no matter the experience. Very experienced mountaineers die too from irrational decisions . Nobodies experience is stronger than cold and nature. And Dyatlov group were just a 20 years old , with not so many winter expeditions behind their backs. Pitching a tent on bare slope without firewood is already a play with death....
But I can't explain the severe body damages to ravine 4 .... I am starting to think that broken ribs are sustained post mortem and that the coroner just did slopy work...who knows.... What do you think?

[Ehtnisba]

Sorry my post was double

[GeneralFailure]

LYUDMILA DUBININA[...] Although it is mentioned that the stomach contained about 100 g of coagulated blood. It is used by some as an indication that the heart was beating and the blood was flowing when tongue was removed from a mouth. The cause of death is stated as hemorrhage into right atrium of the heart, multiple fractured ribs and internal bleeding.[...]

So no, she was not dead when her ribs were broken and her tongue was cut.

[Star man]

Hello everyone ,
I am an old member of the facebook group, but this is my first time writting here. I decided to finally write here and exacrly in this topoc,because this is where I have a personal experience. And when I first read about Dyatlov Pass and tried to compare it to my own experience my first thought was that extreme cold could cause panick in a way they really could have abandon their tent. But let me explain I support the theory only about hy they have left thw tent. Ravine 4 are really a mistery. But..... If we assume their body damages are POST mortem then they are not...
I will not write more about Dyatlov group. I will try to present my experience in similar situations and also only the experience of when me and my friends were in our early 20s.
My father is a mountaineer and I was on ski since the age of 3. The mountain near my home city is not very high (2025m) ,but is famous for its bad weather, and the said strong downhill winds. Let's say I have been there every weekend from December til May for more then 20 years.
These winds are strong,yes. And by strong I mean they are possible to turn you on the ground. In that said mountain there are even cases of turned trees ,but very rare. The point is I  familiar with their sound,strength ,coldness etc... I know that a tent layed down the slope will resist them ,because it is low and these winds act mostly in vicinity. But... This is easy to be said in theory and in day light and in normal situation. What happened once to me and my friends is to show me that in reality people react differently in spite of knowledge and yes sounds of winds and dark and cold CAN effect your reason.
10 years ago me and two guys were up there to ski in fresh snow . It was almost spring and the weather was relatively warm so we wanted to sleep in our tent and catch more fresh snow in the morning. Our tent was in a forest . At about 12 am temperatures dropped , and because we were half asleep probably 2-3 hours passed without us realising that we are actually freezing . By freezing I mean, fingers already numb, speech is hard to be maintained,severe shaking. Imagine waking up in such state. You are already in a bad shape and what you realise is that tent is NOT safe place,because you cannot move to slow down the freezing. Our fingers were so numb we couldn't zip our jackets or unzip the tent. The fingers were numb and twisting like there were no bones and muscles in them. So,even though all of us knew the mountain,knew we are just 40 mins ride from nearest city and even a forest hut was nearby, we were in panic. We couldn't even open the tent,we knew if we stay we may not die,but for sure our limbs would be damaged. So what we did was very similar to what Dyatlov tent looked like. We teared the canvas with lighter - modern tents are polyester I think, so the fire of the lighter melted the fabric and then from the melted holes just stretched the holes with our elbows and bodies. Shoes were impossible to be put on without working fingers . We were well and with no severe frost bite,just because there was a hut with people and fire just 100-200m away. I don't know if there wasn't a hut nearby,if we would have escaped the tent too. I suppose yes, we would have done it and  maybe die or not,but in this situation staying IN the tent was = sertain freezing if not to death to loosing limbs. And in such state you don't think clear no matter the experience. Very experienced mountaineers die too from irrational decisions . Nobodies experience is stronger than cold and nature. And Dyatlov group were just a 20 years old , with not so many winter expeditions behind their backs. Pitching a tent on bare slope without firewood is already a play with death....
But I can't explain the severe body damages to ravine 4 .... I am starting to think that broken ribs are sustained post mortem and that the coroner just did slopy work...who knows.... What do you think?

Interesting story.  I can understand how the cold can make your arms and hands useless.  I have experienced a much more simple situation that was not life threatening.  I was skiing and forgot toput my gloves on which were clipped together on my jacket.  I got onto a chair lift and by the time I got to the top I couldn't use my hands to unclip my gloves.

Let me ask.  When you did leave the tent what did you take with you?  Did you put any outer clothes on?  Did you carry your shoes?  Did you slip your feet into your shoes without fastening them?

In the Dpi there is evidence that they left in areal hurry.  Slobodin did manage to put one boot on, but not the other.  Some of the group were better dressed - Semyon and Kolevatov.  They could have helped the others to put on their warm clothing.

They were able to use matches to light a fire, and they were able to cut fir tree branches with a knife.  They could climb trees and they could use a flashlight.

It doesn't seem like they were all suffering numb fingers and hands.

Regards

Star man