Go Back  Airline Pilot Central Forums > Pilot Lounge > Safety
Malaysian 777 missing >

Malaysian 777 missing

Search

Notices
Safety Accidents, suggestions on improving safety, etc

Malaysian 777 missing

Thread Tools
 
Search this Thread
 
Old 09-03-2015 | 01:01 PM
  #1061  
Gets Weekends Off
 
Joined: Jun 2008
Posts: 3,716
Likes: 0
Default

http://www.nytimes.com/2015/09/04/wo...nion.html?_r=0

http://www.wired.com/2015/09/ok-chun...icially-mh370/
Reply
Old 09-03-2015 | 02:09 PM
  #1062  
UAL T38 Phlyer's Avatar
Moderate Moderator
 
Joined: Mar 2008
Posts: 5,681
Likes: 0
From: Curator at Static Display
Default

Originally Posted by PurpleToolBox
Have they test flown another Malaysian 777 to match the flight track to satellite pings to ensure they're suspected path corresponds with actual flight path?
I have wondered the same thing.

Their premise: the pings stayed the same distance from a geosynchronous satellite over the Indian ocean.

But I wonder: how accurate? Plus or minus how much?

As the +/- tolerance gets bigger, the two arcs from last radar contact (based on the satellite) get wider.

If they get wide enough, they would merge, and literally the entire Indian Ocean is your search area.

DME tolerance is +/- 3%. Are satellite pings the same......or worse?
Reply
Old 09-04-2015 | 04:09 PM
  #1063  
cardiomd's Avatar
Gets Weekends Off
 
Joined: Jul 2009
Posts: 988
Likes: 0
From: Seat: Vegan friendly faux leather
Default

Originally Posted by UAL T38 Phlyer
I have wondered the same thing.

Their premise: the pings stayed the same distance from a geosynchronous satellite over the Indian ocean.

But I wonder: how accurate? Plus or minus how much?

As the +/- tolerance gets bigger, the two arcs from last radar contact (based on the satellite) get wider.

If they get wide enough, they would merge, and literally the entire Indian Ocean is your search area.

DME tolerance is +/- 3%. Are satellite pings the same......or worse?
BTO was on order of 20 us error which mapped to around a 3 km width of the search arc. Inmarsat was very forthcoming and released raw data and there was a great deal of professional and academic independent analysis. Short story is the arcs in the Indian ocean were extremely accurate (the plane was almost certainly within 10 km of the arc) but they were infrequent, and the last arc was received quite a while before the crash.

The doppler motion analysis was not very good (they tried to look at the relativistic / motion shift of the pings to determine direction of travel.)

There was a really nice quite scientific article in aviation week IIRC a year ago or so, I'll try to dig it up and post if you are interested. It addressed those questions and more and was a great read.
Reply
Old 09-04-2015 | 05:02 PM
  #1064  
UAL T38 Phlyer's Avatar
Moderate Moderator
 
Joined: Mar 2008
Posts: 5,681
Likes: 0
From: Curator at Static Display
Default

The probem I have with this whole premise:

I see two scenarios: an incapacitated crew (likely, in my opinion), or a hijacking. (Unlikely, in my view).

For an incapacitated crew, if the controls of a 777 are released, IIRC, it rolls out and flies in a straight line.

If it were hijacked, it would take a lot of skill to fly it on an arc that just happens to stay a constant distance fom a satellite. Even if you knew the point over the Indian ocean that was the satellite's lcation, there is no way to do "turns about a point" using the navigation system....I think its maximum "arc" you can program is about 800 nm. I flew arcs in the military; airline pilots (and hijackers) generally do not, and wouldn't be very proficient at it.

If it were an incapacitated crew and it was on autopilot, same thing: it would follow the route programmed; same improbabilities as a hijacking.

Personally, I believe it flew in a straight line after crew incapacitation, and crashed near where they found the flaperon. Some minor thing has been overlooked in the satellite-ping theory that would prove it a red herring.

My theory, at least.
Reply
Old 09-04-2015 | 09:16 PM
  #1065  
rickair7777's Avatar
Prime Minister/Moderator
Veteran: Navy
 
Joined: Jan 2006
Posts: 45,144
Likes: 801
From: Engines Turn or People Swim
Default

I came up with a (barely) plausible incapacitation theory involving fire and deliberate cabin pressure dumping to fight said fire. Hi alt environment extinguishes fire but also extinguishes crew and pax. FBW airplanes flies on...

But my theory requires some coincidences (no radio call, fire takes out certain avionics, etc).

Much as I prefer to give the crew the BOD, Ocams Razor says it was hijacked. Logic then says it was hijacked by a crew member, because the "usual suspects" or their like would have done something more dramatic than vanish if they were in control of a fully-fueled 777.
Reply
Old 09-08-2015 | 03:51 PM
  #1066  
cardiomd's Avatar
Gets Weekends Off
 
Joined: Jul 2009
Posts: 988
Likes: 0
From: Seat: Vegan friendly faux leather
Default

In response to a few of the posts above, here is a summary of BTO characteristic:

http://www.atsb.gov.au/media/5187038...et_dec2014.pdf

There is a full technical document I remember reading somewhere but I can't find it right now, I'll search my HD to post if people interested. Basically it goes into math of the "cone intersecting a sphere" that gives the arc.

Now even if the arc was exactly right, and modeling the flight path from last known arc, there is additional sea drift components etc. It will be found, but may take a while!
Reply
Old 10-12-2015 | 10:39 AM
  #1067  
New Hire
 
Joined: May 2015
Posts: 3
Likes: 0
Default

Here's today's latest theory... Crashed in the jungle.

MH370 plane wreckage claimed to be found on Philippine island | Daily Mail Online
Reply
Old 10-12-2015 | 12:59 PM
  #1068  
Vital Signs's Avatar
whatever
 
Joined: Sep 2015
Posts: 421
Likes: 0
Default

Sounding more and more like "Lost"
Maybe a billionaire put it there.
Reply
Old 10-12-2015 | 02:13 PM
  #1069  
rickair7777's Avatar
Prime Minister/Moderator
Veteran: Navy
 
Joined: Jan 2006
Posts: 45,144
Likes: 801
From: Engines Turn or People Swim
Default

There's more than a few unlocated wrecks hidden in South Pacific jungles. Might be anything. Locals might not know a 777 from a DC-3.
Reply
Old 10-14-2015 | 09:04 PM
  #1070  
DYNASTY HVY's Avatar
Retired
 
Joined: Feb 2008
Posts: 3,527
Likes: 0
From: whale wrangler
Default

It's a long shot but I wish the media would at least get pictures verifying what someone says they saw before putting it out ,but then again that's just me. Fred
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Roll Inverted and Pull
Major
8
03-04-2008 06:36 PM
boost
Cargo
1
02-01-2008 03:38 PM
Dog Breath
Hangar Talk
8
09-13-2007 08:48 AM
madfoxjay
Part 135
8
09-06-2007 08:25 AM

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



Your Privacy Choices