Malaysian Airlines MH370 contact lost

[Bloxin]

Hypothetical

Hello.
This is my third attempt to make a post here. Maybe, as I'm new here I'm doing it wrong.
I am a licenced engineer, B747.
This post attempts to describe, with precedents, a possible single failure that would cause loss of coms, depressurisation and crew disablement due to hypoxia.

Precedent: QF30 25 July 2008 Pax oxygen bottle "explodes" tearing a hole in fuselage.

Ref: Please google "Qantas oxygen bottle explosion" and view photos of damage.
The picture taken inside the fwd cargo compartment shows one bottle missing.
there is no evidence of shrapnel damage in the photo. Therefore, no eplosion.
The bottle appears to have detached itself from its connections and propelled itself down through the fuselage skin.

777: The crew oxygen bottle is mounted horizontaly on the left aft wall of the nose wheel well structure with the fittings (propelling nozzle) facing forward. This aims the bottle, in the event of a QF30 type failure, directly into the MEC containing all boxes concerned with coms and a lot more.
Before all of its energy is spent, an huge amount of damage could be caused to equipment and the bottle could, conceivably, cause a decompression.
When the crew respond by doning oxygen mask, there is no oxygen and hypoxia is the next link in this proposed chain of events.
This link is entitled "Hypothetical" and is only that. I believe it ticks a few boxes.
Hoping this post makes it and generates some discussion.

*** Above info on position of fittings incorrect. Further research reveals... ***

TURIN

I noted your original post saying that the crew O2 bottle fittings were on the aft side of the bottle and thought that the the wind was blown out of my hypothetical sail.

However. I have done some more research on the QF30 incident and found in the Australian Transport Safety Bureau report that the bottle was propelled upward through the cabin floor where it damaged a door handle, some trim and then dove back through the hole in the floor and exited the aircraft via the hole in the fuselage... RUBBISH??? Thats what I thought.

However. There is a photo tab on the web page. The last photo of the set is of an O2 bottle sized hole in the floor panel directly above the hole in thefuselage.

The Pax O2 bottles in the 747 fwd cargo sidewall stand vertically. Plumbing on top.

The missing bottle was not found onboard.

Ref: Australian Transport Safety Bureau website

Aviation safety investigations and reports

Search: July 2008 and QF30 is top of the list

All. My hypothetical structure ofevents is purely speculative, as most here are, until we get some real facts towork with.

Thank you. Blox in.

[Flutter speed]

Which raises multiple questions of:

What O/S the server was running?
Was it properly patched?
Was it's Anti-virus up to date?
Could any of the pax hack in through their Wifi connections?

etcetc.

The 777 has highly specialized software running, not your typical windows desktop, or unix for that matter. It is in that sense a generation behind the likes of 787 and A380, which are running on more 'pc like' computers. While the 777 does have a sort of central computer (AIMS) it still is not much more than a rack of proprietary (Honeywell) avionics boxes which are more tightly integrated than previous generations (pre 777).

777 has no server really, it has patches but these are general software (Blockpoints) updates. Don't think virus are an issue. Hacking wifi (if installed, might require access to the maintenance terminals) is not an issue.

[Lost in Saigon]

Originally Posted by mabuhay_2000

It seems utter madness to have the aircraft's flight computers on the same network was the PAX WiFi.

Aircraft don't use the internet for navigation or communication. Some aircraft have internet capability for passenger entertainment only.

[XB70_Valkyrie]

0121 Last radio contact
0130 Last ATC Radar contact
- then onto Military Radar, turn west to west peninsular -
0215 Military Radar loses the unidentified aircraft 200nm NW of Penang at an altitude of 29,500ft (FL295)

You're assuming this transition from ATC too military was contiguous. I'm sure it isn't. The military have some returns along a westerly track at FL295. They may or may not originate with the ATC flight path (I would say likely NOT). They don't know what aircraft they are from, and that's the problem.

[Flutter speed]

any PAX with the right apps loaded onto a laptop or tablet would be able to hack into the flight computers.

Simply not true. Again, there is no central computer which 'controls' the aircraft. The FCS computers are anyway separate from the main AIMS (central) computers (and are triple triple redundant). The AIMS itself contains very important, but not critical avionics required for keeping the plane in the air.

[mabuhay_2000]

What????

I've been out for a few hours and only heard snippets of news, but it seems that the Malaysian side are tying themselves in knots.

We have the RMAF saying they did track a plane that would fit the profile of MH370 flying back across Malaysia, then the head honcho said he didn't say that but didn't deny it was true, then he said that they actually had tracked a blip back across Malaysia. I mean, make your mind up!

The Vietnamese worked them into a corner by saying they had tracked MH370 turning west AND they told the Malaysians pretty much straight away.

Then the Malaysians said the tracked the blip some 200 (TWO HUNDRED!) miles past Penang, which would have them two thirds of the way to North Sumatra, with every indication that the blip was still flying and went out of range of the radar.

There is so much conflicting information that it's impossible to know what's really going on!

[VinRouge]

if the jet were fitted with internet suite, to be honest, thats one thing that even I would not have thought to disable never mind a hijacker. If there was any sign of kerfuffle, there would have been messages all over the place, a bit similar to the phone calls made on 9/11 by passengers on the final AA jet that went in.

As to the search area, one of two options. Its either close in to the point at which contact was lost (bomb) or its on the perimeter of a big circle determined by fuel remaining and global winds, IF, and only if, its suspected the jet flew on for whatever reason. We dont have a search area the radius of the max flight range, we realistically have those 2 options. As SAR have two potential directions, again, I suspect any wreckage left post crash floating will be found once some lateral thought has been applied to the problem. Together with satellite , if there is wreckage, they will find it soon enough.

[BOAC]

Originally Posted by Vin Rouge

Its either close in to the point at which contact was lost (bomb) or its on the perimeter of a big circle determined by fuel remaining and global winds.

- or somewhere in between?

Did the retired ex-BA F/O have any theories why a hypoxic crew would turn off the transponder?

[ShenziRubani]

Evenrude

Join Date: Jul 2012
Location: Debatable
Posts: 9
Tomnod search
Interesting sattelite image found on Tomnod.

Malaysia Airlines MH370 / TomNod crowd-search - CNN iReport



this is a barge with a side boat.

[xcitation]

Could you please elaborate on Hypoxia (or for that matter aircraft air supply suddenly contaminated with some kind of life ending substance). I believe this is the only angle that has not been debated to death on this forum.

Slow pinhole leaks can be as dangerous as a rapid decompression. The resulting insidious onset of hypoxia on the brain can be similar to alcohol intoxication. The effects vary by individual: impaired cognitive function, euphoria and overconfidence, lethargy or angry and un-cooperative. There are sensors and alarms to warn of loss in cabin pressure which should result in immediate action.

Helios Airways Flight 522 is a tragic example.

[DarkStar]

Did the retired ex-BA F/O have any theories why a hypoxic crew would turn off the transponder?

If I remember correctly he said ....'that's a tricky one'

[Orenda]

Indonesian radar coverage

I have seen numerous postings about whether the Indonesian military or civilian radars saw anything of MH370. Indonesia's military radar coverage is spotty at best and non-existant in many parts of the Archipelago unless a naval vessel happens to be in the area.

[Lost in Saigon]

Originally Posted by xcitation

Slow pinhole leaks can be as dangerous as a rapid decompression. The resulting insidious onset of hypoxia on the brain can be similar to alcohol intoxication. The effects vary by individual: impaired cognitive function, euphoria and overconfidence, lethargy or angry and un-cooperative. There are sensors and alarms to warn of loss in cabin pressure which should result in immediate action.

Helios Airways Flight 522 is a tragic example.

A slow pinhole leak is only dangerous if the crew allows themselves to become distracted to the point they ignore the aircraft's automated warnings.

When the cabin altitude reaches 10,000 feet an alarm will notify the crew. At roughly 13,000 feet the passenger oxygen masks will drop.

[paultr]

@RetiredF4
Your post regarding the way military primary radar works makes perfect sense. I can imagine that the identity of commercial air traffic is appended to its related target/return. As you say, the military radar operative would know exactly what the target was that had now turned around and was flying back over his airspace.

I have some experience of using primary radar in a recreational marine environment and when you are monitoring radar 'in anger' such as thick fog it is quite easy to work out what is what after working the set for a while. The system we use for secondary radar is called AIS and all commercial traffic is tagged with name/course/speed etc. The Malaysian military radar operative would have known what all the targets on his set were - otherwise what is the point of monitoring it at all ?

I realise this is more or less a repeat of your post but I find it staggering that 5 days on, the Malaysian authorities are saying it needs further analysis.

[mixture]

I have no experience with aviation technology, but with TTE it should be possible to run Inflight Entertainment on the same network as the flight-control system.

Read the description !

TEthernet® (SAE AS6802) is a scalable, open real-time Ethernet platform used for safety-related applications primarily in transportation industries and industrial automation

TTEthernet-based solutions provide:
determinism
availability
safety
fault tolerance
security
hard real-time operation
synchronization

None of those are features you need for IFE systems. Its quite obvious from the manufacturers description what it's for !

[golfbananajam]

response to post #2358

BBC "expert" apparently researched this a bit earlier today and the oil company operating the rig claim to have no employee of that name on that rig

Possibly another red herring

[VinRouge]

A slow pinhole leak is only dangerous if the crew allows themselves to become distracted to the point they ignore the aircraft's automated warnings.

Slow pinhole leak? Have you seen the size of the outflow valve?!

[Ian W]

Originally Posted by Lost in Saigon

A slow pinhole leak is only dangerous if the crew allows themselves to become distracted to the point they ignore the aircraft's automated warnings.

When the cabin altitude reaches 10,000 feet an alarm will notify the crew. At roughly 13,000 feet the passenger oxygen masks will drop.

Not only that but ACARS would have issued a message with the Cabin Altitude warning. This would occur before anyone was affected. No such ACARS has been admitted to.

[hogey74]

regarding the oil rig report

I wonder if something like this could be a factor ...

https://en.wikipedia.org/wiki/Fata_Morgana_(mirage)

The email from that Kiwi engineer reads pretty credibly so I took it seriously enough to plot his position on Google Earth and do some Googling on things that might affect perceptions of distance and how he reported that the burning stopped mid-air. I've wasted enough time on youtube to have noticed that nuclear explosions often seem to have strange light propagation effects. I googled the good old Min Min light and found the above effect. This situation while obviously uncertain, seems to at least not rule it out.

Just wondering if maybe the bearing is close but the distance isn't? The strong light of a bright fire bouncing off layers might account for the fact that the burning stopped mid air?

[LASJayhawk]

Is it really that ridiculous? Maybe you should look up Hugh Teso on Google and read about what he did. You might be surprised.

And, for the sceptics, he demonstrated the hack in action with real aircraft computers.

It's actually a pretty simple exploit, using ACARS to substitute data from base with data he sends from the smartphone. He was able to also heading and altitude via the exploit. He also managed to hack the ADS-B transmitter.

Any system that transmits data wirelessly can, eventually, be hacked. All it needs is access to the OS used and, eventually, the hacker will find a way in. It's a matter of 'convincing' the aircraft's systems that you're giving it the real data.

It made an impressive display, but I highly doubt you could pull it off in the real world.

While there is a "master" buss that most everything talks to, most boxes output multiple busses, some of which only go to 1 place. For example an ADIRU may have 1 talk to everyone bus, 1 that only talks to FMS 1, 1 that only talks to ADIRU 2, etc.

If the FMS sees different data from the master buss, and different data from it's protected bus, it will raise its BS flag. I have seen this real world in a Hawker, the MFD symbol generator was spitting out mismatched data, and both Universal FMS's refused to go into approach mode. (I found the fault, by pulling breakers one at a time till they went into approach mode)

Upshot is, in the real world, you could make the avionics throw a temper tantrum and give the pilots a headache, but you couldn't turn the bird into your own personal drone.