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Final two communications from MH370 support controlled descent scenario (2021)

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Re: Final two communications from MH370 support controlled descent scenario (2021)

#31

Post by krisoft »

Hackbraten wrote: post #21
heavenlyblue wrote: post #18

Earlier quoted context omitted.

Do you mean underwater? Apologies it's not clear if it's a joke?

Most people can’t breathe at high altitudes due to insufficient air pressure. That’s why airplanes are usually pressurized. If that extra pressure goes away for whatever reason, people are handed oxygen masks and tanks to help them stay alive. What the GP comment says is that the plane may have been depressurized at one point at high altitude. The pilot’s oxygen mask is usually designed to last longer than any of the…

> Most people can’t breathe at high altitudes due to insufficient air pressure.

Not most people. Nobody can breath if the altitude is high enough. There are some individual variability in how high is too high. That is of interest if you go mountaineering, but not really in a situation where an aircraft rapidly decompresses at the altitude MH370 was speculated to be flying at.

Re: Final two communications from MH370 support controlled descent scenario (2021)

#32

Post by CalRobert »

Sakos wrote: post #29
foldr wrote: post #27

Earlier quoted context omitted.

You can't really "land" in the Indian Ocean in an airliner. There has (famously) been a successful ditching of an airliner in a river, but I don't think there has ever been a successful ditching in the open ocean. Here's the kind of thing you can expect to happen even in much more favorable sea conditions close to the shore: https://www.reddit.com/r/CatastrophicFailure/comments/3f7fkk... (There were a number of survi…

I don't know why I thought a controlled landing of a plane on water was generally possible. Maybe because of the pre-safety instructions where it sort of implies (maybe it's just me) that if a plane were to land on water, I could just put on a life vest, get the raft and get off. Looking at that footage and the death toll, feels like a miracle even that many people survived. That makes me wonder if being able to land…

It's definitely something that is considered, and the miracle on the Hudson included use of the A320's ditch mode if I recall correctly.

https://www.pprune.org/tech-log/358285-airbus-ditching-butto...

Looks to be in a few airbus models.

https://simpleflying.com/airbus-aircraft-ditch-switch-emerge...

If I recall correctly I've read that the bigger the plane the less likely it is to work but I don't have sources.

Re: Final two communications from MH370 support controlled descent scenario (2021)

#33

Post by Hnrobert42 »

foldr wrote: post #27
sinuhe69 wrote: post #2

If the descent was controlled gliding, the passengers (at least some of them) should be alive upon landing, shouldn’t they? Where are they now? Which theory could explain the absolute silence?

You can't really "land" in the Indian Ocean in an airliner. There has (famously) been a successful ditching of an airliner in a river, but I don't think there has ever been a successful ditching in the open ocean. Here's the kind of thing you can expect to happen even in much more favorable sea conditions close to the shore: https://www.reddit.com/r/CatastrophicFailure/comments/3f7fkk... (There were a number of survi…

You are correct about the difficulty of ditching in the ocean. See Admiral Cloudberg's description of ditching a DC-9 in the Caribbean during bad weather. There were many survivors.

https://admiralcloudberg.medium.com/down-in-deep-water-the-d...

Re: Final two communications from MH370 support controlled descent scenario (2021)

#34

Post by grotorea »

JumpCrisscross wrote: post #20
sofixa wrote: post #17

If anyone is interested in recently made content that recaps the whole thing, all the available information, some of the speculation, including the most recent news/information: * video by Mentour Pilot - https://youtu.be/Y5K9HBiJpuk * great read, as usual, by Admiral Cloudberg, slightly older: https://admiralcloudberg.medium.com/call-of-the-void-seven-y...

“Malaysia Airlines operations…were tracking the plane on the Flight Explorer website, which, as they would only realize hours later, simply continued to display an aircraft’s projected path if its transponder stopped broadcasting position information.” What in the actual fuck. “…the supposed signals from the black boxes must have been false. Only much later was it discovered that the signals had probably come from th…

After a lot of aircraft accident youtube videos, I can think of a couple where people misunderstanding where their computers get their information from and how they work.

* This one where the operations team apparently doesn't understand how their flight tracker works, and/or it fails to inform their users that last contact was X hours ago.

* One where the aircraft has a broken altimeter, and the suspicious pilots decide to ask the ATC for altitude confirmation, but the ATC radar only gets horizontal coordinates, the altitude information that ATC sees actually comes from a datastream from the aircraft itself. So they fatally decided to trust that instead of their own aircraft radar altimeter which was correctly telling them they were about to crash.

* The aircraft had either a single failed engine or the wheels were stuck outside, and the pilots asked the computer for how far they could travel in their current state, assuming it worked like a car, by projecting current consumption, but actually the computer just uses fixed data that does not take such exceptional situations into account. So they ran out of fuel early.

> “ATSB chose to assume that the plane spiraled in close to the seventh arc because it had not received enough funding to extend the width of the search area to 100 nautical miles.”

> WAT.

It seems the police department has insufficient funding to help drunks look for keys in the dark.

Re: Final two communications from MH370 support controlled descent scenario (2021)

#35

Post by krisoft »

Sakos wrote: post #29
foldr wrote: post #27

Earlier quoted context omitted.

You can't really "land" in the Indian Ocean in an airliner. There has (famously) been a successful ditching of an airliner in a river, but I don't think there has ever been a successful ditching in the open ocean. Here's the kind of thing you can expect to happen even in much more favorable sea conditions close to the shore: https://www.reddit.com/r/CatastrophicFailure/comments/3f7fkk... (There were a number of survi…

I don't know why I thought a controlled landing of a plane on water was generally possible. Maybe because of the pre-safety instructions where it sort of implies (maybe it's just me) that if a plane were to land on water, I could just put on a life vest, get the raft and get off. Looking at that footage and the death toll, feels like a miracle even that many people survived. That makes me wonder if being able to land…

> I don't know why I thought a controlled landing of a plane on water was generally possible.

Because it is possible and foldr is incorrect in stating that it is not possible.

On the video he linked panicked hijackers were fighting with the pilots for the controls. Clearly that is not an ideal scenario for any kind of landing. Even more so for a tricky water landing one. But that is more of a reason to avoid hijackers fighting with the pilots, not proof that ditching is impossible.

Water landings are clearly not the preferred way to land. They are very risky. But they are also not as impossible as that comment makes them out to be. Here is a list of them from wikipedia: https://en.wikipedia.org/wiki/Water_landing

Re: Final two communications from MH370 support controlled descent scenario (2021)

#36

Post by foldr »

Hnrobert42 wrote: post #33
foldr wrote: post #27

Earlier quoted context omitted.

You can't really "land" in the Indian Ocean in an airliner. There has (famously) been a successful ditching of an airliner in a river, but I don't think there has ever been a successful ditching in the open ocean. Here's the kind of thing you can expect to happen even in much more favorable sea conditions close to the shore: https://www.reddit.com/r/CatastrophicFailure/comments/3f7fkk... (There were a number of survi…

You are correct about the difficulty of ditching in the ocean. See Admiral Cloudberg's description of ditching a DC-9 in the Caribbean during bad weather. There were many survivors. https://admiralcloudberg.medium.com/down-in-deep-water-the-d...

Very interesting article. Worth noting that the position and size of the engines on the DC-9 would likely be more favorable for ditching than that of most modern airliners. The low and very large underwing engines generate a huge yaw force as soon as they contact the water, and it's very difficult to get both to contact at exactly the same time in a rough sea.

Re: Final two communications from MH370 support controlled descent scenario (2021)

#37

Post by grotorea »

voidUpdate wrote: post #6

The repeated references to "riddles" feels a bit strange (in regards to the captain's home flight simulator tracks). I'm not sure if it's a strange translation or ESL thing, but it just feels like a strange word choice, like this is the start of a Dan Brown book or something

I'm ESL myself but I feel such poetic language is at least somewhat appropriate for MH370, probably one of the greatest real-world mysteries of the 21st century, no?

Re: Final two communications from MH370 support controlled descent scenario (2021)

#38

Post by foldr »

krisoft wrote: post #35
Sakos wrote: post #29

Earlier quoted context omitted.

I don't know why I thought a controlled landing of a plane on water was generally possible. Maybe because of the pre-safety instructions where it sort of implies (maybe it's just me) that if a plane were to land on water, I could just put on a life vest, get the raft and get off. Looking at that footage and the death toll, feels like a miracle even that many people survived. That makes me wonder if being able to land…

> I don't know why I thought a controlled landing of a plane on water was generally possible. Because it is possible and foldr is incorrect in stating that it is not possible. On the video he linked panicked hijackers were fighting with the pilots for the controls. Clearly that is not an ideal scenario for any kind of landing. Even more so for a tricky water landing one. But that is more of a reason to avoid hijacker…

I didn't say that water landings in general are not possible (though they are difficult even under ideal conditions). I said that landing in the open ocean is not really something that has been done successfully in a modern airliner.

The closest example I could find in the list you link was the following. But it ditched a few miles from the coast and had much smaller engines than a typical modern passenger airliner. Also, it was a cargo flight with only the pilots on board, and the captain was seriously injured.

https://en.wikipedia.org/wiki/Transair_Flight_810

Re: Final two communications from MH370 support controlled descent scenario (2021)

#39

Post by krisoft »

JumpCrisscross wrote: post #20
sofixa wrote: post #17

If anyone is interested in recently made content that recaps the whole thing, all the available information, some of the speculation, including the most recent news/information: * video by Mentour Pilot - https://youtu.be/Y5K9HBiJpuk * great read, as usual, by Admiral Cloudberg, slightly older: https://admiralcloudberg.medium.com/call-of-the-void-seven-y...

“Malaysia Airlines operations…were tracking the plane on the Flight Explorer website, which, as they would only realize hours later, simply continued to display an aircraft’s projected path if its transponder stopped broadcasting position information.” What in the actual fuck. “…the supposed signals from the black boxes must have been false. Only much later was it discovered that the signals had probably come from th…

> WAT.

What what? Do you want to pay for the search? How much do you want to pay for it? Every human endeavour is constrained by resources. The art of doing anything is figuring out how to best employ the available resources to achieve goals.

> What in the actual fuck.

Is this your first time hearing about humans being confused by complicated technology?

Re: Final two communications from MH370 support controlled descent scenario (2021)

#40

Post by Sakos »

krisoft wrote: post #35
Sakos wrote: post #29

Earlier quoted context omitted.

I don't know why I thought a controlled landing of a plane on water was generally possible. Maybe because of the pre-safety instructions where it sort of implies (maybe it's just me) that if a plane were to land on water, I could just put on a life vest, get the raft and get off. Looking at that footage and the death toll, feels like a miracle even that many people survived. That makes me wonder if being able to land…

> I don't know why I thought a controlled landing of a plane on water was generally possible. Because it is possible and foldr is incorrect in stating that it is not possible. On the video he linked panicked hijackers were fighting with the pilots for the controls. Clearly that is not an ideal scenario for any kind of landing. Even more so for a tricky water landing one. But that is more of a reason to avoid hijacker…

I'm looking at how many fatalities many of those incidents had and I'm not sure I'm convinced. They're not impossible, but the odds don't look great.
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