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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)

#101

Post by someguydave »

GJim wrote: post #59
l33tman wrote: post #13

What happened to that other research team who used amateur radio network packet metadata that had been saved, to track airplanes including MH370 and showed tracks that also matched the satellite pings? Can't remember the name of that group though...

If they could track MH370 using WSPR (amateur radio), then they could logically track other (similar) aircraft. When asked to prove the above and publish a peer reviewed paper, they were unable to do so. The reader is thus invited to draw their own conclusion.

Yeah I am personally skeptical that WSPR data could reliably track anything

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

#102

Post by wkat4242 »

Zealotux wrote: post #4
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?

It's possible for the pilot to depressurise the plane and use their dedicated oxygen system to breathe while everyone else on board will pass out after using their individual masks. Doing so will give them 60-90 minutes of extra air, the passengers' masks don't last that long.

Yeah this happened on that Helios flight. Although not on purpose.

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

#103

Post by cccbbbaaa »

runxel wrote: post #41

There is a very good book by the french journalist Florence de Changy about MH370, which "solves" all the issues with most of the theories out there and proposes what really happened. So far I've not come across a more sophisticated theory that still passes Occam's Razor.

Changy recently claimed on BFM TV that she made her scenario up after being pressured by her editor.

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

#104

Post by imglorp »

gymbeaux wrote: post #94
imglorp wrote: post #89

In context of the paper, "high-speed gravitationally accelerated dive following fuel starvation", it bears mentioning the L/D ratio of a 777 is around 20. Which means if you lose power at 35,000 feet, you can have at most 132 miles of glide to the surface if well piloted. https://aviation.stackexchange.com/questions/56420/lift-to-d...

What are the assumptions for the “132 miles” figure? At the very least wind is going to affect that- if you’re in a headwind you could probably make it closer to 150 miles (albeit not a huge gain).

Yeah that's why I said at most, so assuming still air and perfect piloting. The worst case is lawn dart, 0 glide.

35000 ft x 20 ratio x 1/5280 mi/ft

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

#105

Post by egormakarov »

gymbeaux wrote: post #94
imglorp wrote: post #89

In context of the paper, "high-speed gravitationally accelerated dive following fuel starvation", it bears mentioning the L/D ratio of a 777 is around 20. Which means if you lose power at 35,000 feet, you can have at most 132 miles of glide to the surface if well piloted. https://aviation.stackexchange.com/questions/56420/lift-to-d...

What are the assumptions for the “132 miles” figure? At the very least wind is going to affect that- if you’re in a headwind you could probably make it closer to 150 miles (albeit not a huge gain).

It's other way around, with headwind you will get less distance over ground

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

#106

Post by GJim »

beachy wrote: post #67
GJim wrote: post #59

Earlier quoted context omitted.

If they could track MH370 using WSPR (amateur radio), then they could logically track other (similar) aircraft. When asked to prove the above and publish a peer reviewed paper, they were unable to do so. The reader is thus invited to draw their own conclusion.

Publishing a peer reviewed paper would equate to handing their IP over for free. Maybe the right thing to do in the face of such a tragedy is to do that. Or perhaps they genuinely have some cool technology, and it could be sold into aero, military industries and they want to monetize it. In that case the right thing to do would be to hand over their projected track data, which it sounds like they did.

> perhaps they genuinely have some cool technology.... want to monetize it.

They haven't published a patent either.

Again, the reader is invited to draw their own conclusion.

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

#107

Post by mytailorisrich »

jtc331 wrote: post #95
mytailorisrich wrote: post #30

Earlier quoted context omitted.

Debris of the plane were recovered. The plane crashed.

What is in dispute isn’t that it crashed but how it crashed.

I am replying to a specific comment not to the article in general.

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

#108

Post by lxgr »

coredog64 wrote: post #99
beerandt wrote: post #87

Earlier quoted context omitted.

Not knowing your altimeter is connected to your transponder, and that you provide the altitude along with your squawk to the atc screens is a pretty glaring wtf.

ATC does have access to radar that locates aircraft via skin paint. TBH, I’d push that back on ATC. If I’m confused about my altitude, it’s not because I suddenly can’t read the numbers on the dial. ATC should understand that the confusion can be resolved by checking with an outside source.

What do you mean by “skin paint”?

Civil primary radar usually isn’t 3D and does indeed depend on transponder, i.e. secondary radar, supplied altitude data.

They should know what their radar supports in any case, and get suspicious when an aircraft asks them for a readback of airplane-supported altitude data.

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

#109

Post by tim333 »

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…

>Transair Flight 810, a Boeing 737-200 converted freighter aircraft ditched near Oahu and no one was killed though the plane was not well.

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

#110

Post by aaronmdjones »

coredog64 wrote: post #99
beerandt wrote: post #87

Earlier quoted context omitted.

Not knowing your altimeter is connected to your transponder, and that you provide the altitude along with your squawk to the atc screens is a pretty glaring wtf.

ATC does have access to radar that locates aircraft via skin paint. TBH, I’d push that back on ATC. If I’m confused about my altitude, it’s not because I suddenly can’t read the numbers on the dial. ATC should understand that the confusion can be resolved by checking with an outside source.

Primary radar as used by ATC is extremely limited. It is not designed to identify targets at all; nor does it have particularly good vertical resolution. It can tell you where in 2D space a plane is, but without secondary radar and a cooperating transponder, it can't tell you what plane it is, and its uncertainty with respect to altitude can be several thousand feet.
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