Ocean Shield - SSS search
 

AMSA have recently defined the search area as within a circle of 10km radius centered on the 2nd ping detection. That area is defined by the White circle on the graphic below. The rectangular area on a major axis of 030°/210° represents what previous AIS position reports indicate the area the Bluefin 21 AUV is working in. Each days positions are a different color, and the first position for today (20/04:03z) is shown in a Cerise color.

The Red stars represent when pings were acquired, and the sequence is numbered anticlockwise starting at the top. The White star is the position that the pings associated with the first ping were lost (LOS).

http://oi57.tinypic.com/2uo2eds.jpg

NOTE: Use Ctrl+ as many times as needed to enlarge the image, and Ctrl 0 will return the page size to normal.

The speculation about possible ADIRU software and windscreen problems being an issue in this case begs the question:

<< IF >> one or both of these had been a contributory factor, and assuming substantial recovery of wreckage, would the investigators have any chance of finding evidence of it? Particularly as a windscreen cracked by altitude/pressure changes might resemble one cracked on contact with water.

Just on the issue of windshield failure, there is an interesting digression on the manufacture of the above, in the TSB report pertaining to


AIR FRANCE
BOEING 777-228ER F-GSPZ
CHURCHILL, MANITOBA 290 nm NE
17 OCTOBER 2002


where an arc resulting from overheating in the J5 terminal caused a small fire and the windshield to crack.


I won't link as I can't get it through moderation,

but anyway comms were not affected (obviously)

so if this were a contributing factor in the present case we would need to find a reason for lack of comms.


ETA (from the report)


'Boeing has undertaken a program to redesign the window terminal block to eliminate the screw connection. The new window blocks were scheduled to be incorporated into Boeing 777 aircraft, Line Number 471 (delivery date February 2004). The new design incorporates a locking pin/socket, which will address issues concerning loose or cross-threaded screws and inset ferrules. All Boeing 747, 757, 767 and 777 windows delivered thereafter, either on new aeroplanes or as spares, will have the new terminals installed. Boeing intends to deliver spares in kit form with the new wire end terminals included. The operator will have to remove the existing wire end terminal and splice in the new one when replacing windows on existing aircraft. The intent is to eliminate concerns with arcing at the window power terminals.


Boeing released a Fleet Team Digest article to B757 operators in May 2003, discussing terminal arcing and overheating. The article detailed actions to incorporate re-designed terminals into the affected cockpit windows.'




I'm not sure how relevant this might be, but it looks like there was no retro-fitting of the new system so as far as I can figure out, 9M-MRO will have had the original sort.

CVR Question
 

Holdatcharlie,

As other people above have stated, when data on a PC or MAC has been deleted, the sectors on which the data resides is only flagged as deleted in the file allocation table. On the old 30 minute analogue tape CVR, it may still have been possible to recover over written audio, because the erasure head isn't always perfectly aligned with the recording head. or may not reset every magnetic fibre on the tape But on modern solid state digital CVR it is impossible because the memory modules only has 30 minutes or 2 hours of storage space depending on which model is on the plane, so the oldest data is constantly being over written by new data. The older data is completely erased.

I hope this helps.

Finding more cabin recordings
 

The hope is on finding more cabin recordings based on passengers' personal devices being used during those dramatic final hours (i.e. smartphones, videocameras, etc.). Their memories might still be readable if sea water has not degraded its components seriously.

Yawn ! :ugh:

You've already been told above not to compare the generic IT industry to the niche part of the IT industry that deals with safety-critical systems.

Windows and such like are not subjected to the same formal design process that safety critical systems are. Thus of course you will get a greater number of bugs, some of which may cause substantial issues to the stability of the system. Bleeding edge generic IT projects these days can use agile development.....no such thing in safety critical systems.... in safety critical systems there is a traceability requirement for you to be able to show that a given line of source code fulfils given requirement specifications, the level of detail is truly excruciatingly tedious... but it all serves a very important purpose !

Sure there's always scope for issues, but the whole point of the almost obsessive-compulsive development methodology for safety critical systems is that failure or bugs won't kill anyone !

On another note....

"Malaysian authorities are considering issuing death certificates for the missing passengers of MH370.
It's part of the plan to provide financial assistance to the families of passengers.
Deputy Foreign Minister Hamzah Zainudin, head of the next of kin committee, said no decision had been made on how much each family might receive".

Er ? The Montreal Convention.
Or is the carrier going to prove that they are totally "without fault".

It's quite a mute point to be fair, because given the advances in technology if you're going to revisit the black box (and I think AF447 and MH370 prove there's at least a need for an updated spec, even if the cost-benefit analysis doesn't include retrofitting) then you'd include enough non-volatile storage per box to take many many hours of recording (along with other things such as an extendable, floating additional antenna).

Oil slick
 

I think I have read every forum page but have heard no news of the analysis of the two oil slicks, did I miss it ?

Review the JACC media release recently. Confirmed oil not from a plane.

It strikes me that these days (a duplicate copy of) the recorded flight data from both black boxes could in fact be stored in something physically tiny that was entirely self contained and external to the plane. There have been demands for a transponder to be carried that cannot be disabled by the crew, under duress or otherwise, so how about a little unit, externally mounted, on the tail cone perhaps, top of the fuselage or tip of the fin. No physical connection to aircraft power or systems, powered by an on board battery, which in turn is charged by a miniature RAM air turbine when the aircraft is moving. Include a transponder that will respond on demand to an internationally standardised IFF style interrogation challenge, or maybe regularly just pings co-ordinates to a satellite. If the same device also contains a non-volatile memory module which is written to from inside the plane via a bluetooth interface from the _real_ black boxes, with a facimile copy of both CVR & FDR data, all in a package designed to survive a water landing and end up on the surface amongst the debris field, if there is one, perhaps with the on-board satellite pinger previously mentioned still operating, then this situation literally can't happen again...

joy ride:-
Without going into the microscopic details, I would reckon a fracture attributed to internal forces (failure with cabin pressurised) and one due to external forces (impact with water) will be pretty evident on close examination.

I really hope I'm wrong but it's not looking good for finding the aircraft in that 10km radius zone. It seems more than 2/3rd has been searched to no avail.

The Malaysians have long labelled the investigation as being a criminal one. One can only assume, it wasn't a knee jerk reaction and that they have solid reason to do so.

"Bluefin-21 has searched approximately 50 per cent of the focused underwater search area to date."
Search and recovery continues for Malaysian flight MH370

The JACC were a little more non committal than that:

"Preliminary analysis of the sample collected by ADV Ocean Shield has confirmed that it is not aircraft engine oil or hydraulic fluid". (source: JACC website)

Howard Hughes,
Are you suggesting that the oil is not totally discounted as being from the aircraft and that it could be from cargo? E.g. an electrical transformer ruptured in the crash?

I notice in the JACC Press release that 11 aircraft are still being used
and this seems to be the case on a daily basis.

Not all the aircraft can drop buoys but are they still searching for debris, pings ????

Any comments ?

Nevertheless, there is a good chance the non-volatile memory would retain its data which could potentially be recovered. If you'd broken your phone by going for a swim you wouldn't bother because the phone is not economically recoverable - but if it's a question of recovering data for a crash investigation that's another matter.

I am just pointing out that they have given themselves a little room to move! :ok:

Latest JACC media release
 

Media Release
21 April 2014—am

Up to 10 military aircraft and 11 ships will assist in today's search for missing Malaysia Airlines flight MH370.

Today the Australian Maritime Safety Authority has planned a visual search area totaling approximately 49,491 square kilometres. The centre of the search area lies approximately 1741 kilometres north west of Perth.

This morning, Bluefin-21 AUV completed mission eight in the underwater search area. Bluefin-21 has searched approximately two thirds of the focused underwater search area to date. No contacts of interest have been found to date.

The focused underwater search area is defined as a circle of 10km radius around the second Towed Pinger Locator detection which occurred on 8 April.

Bluefin-21 AUV's ninth mission will commence later this morning.

The weather forecast for today has conditions deteriorating, particularly in the north of the search area, as Tropical Cyclone Jack continues its track southwards. Wide spread showers are developing with isolated thunderstorms to the north and east south-easterly winds.