Nemrytter

What makes you so sure of that? Just because the data has not been 'officially' released to the public does not mean that it has not been checked by others. I can't see what good releasing all the data would do other than to satisfy the rabid demand of the media/public.

rh200

There is indeed various scientific institutions looking a various data and providing independent analysis input to the search group. This is a fact.

LGMX

Was not that they brought down the aircraft. It was about whether upon contact with seawater or upon decomposition/discharge/etc they might emit something that could be detected from a distance using satellite sensing technology. I read that overcharging them can cause the formation of cobalt but a chemist would know more.

SAMPUBLIUS

PUUUHHHHLLEESE - all the speculation about finding traces of any so called chemical reaction traces in a few thousand square miles of salt water - OR that they had any significant effects on the routing- failure to comm- etc is simply that- and does not add at all to the subject. start a different thread-

Thank you !

JamesGV

So the Malaysian's "Prelim" report recommends the "real time streaming" of data....

I think they better read the report if that is their findings !

Their ATC protocols and practices are clearly "unsafe" or being ignored.
If they can't get that right, then what hope for the investigation.

henra

Not really necessary.
These things burn intensely/violently for less than 10s. The remainder will stop to smolder and burn in not much more than a minute if at all. It's this first minute that counts.
The important and difficult thing is to relieve the pressure and fireball that builds instantly without letting the hot gases ignite surrounding material or blow up the container. It's a bit like Black Powder. You mustn't allow it to build up pressure in its containment. If within 1 minute nothing else started burning the danger is more or less over.

Regular Suppression Systems are extremely important in order to extinguish surrounding material that was ignited by a LiIon fire. The volume of packs of cells should be small enough that the violent Initial fire doesn't directly cause structural or flight control damage. And the distance between packs of cells needed be sufficient that no direct heat Transfer between the packs can take place that would ignite the next pack. Fire suppresion must be capable of extinguishing other material that is stored between the packs. Then, everything should be OK. Putting all the packs in one Container is a bad idea since it enables one run away pack to ignite others and thereby creating a very violent fire.
Edit:
Regarding relevance for MH370: Probably very low. Almost 3t (!!!) of LiIon in one Container would in all likelyhood have brought the plane down in a few minutes once ignited. Hardly conceivable that it would smolder for hours.
The Trouble with the freighters is that they don't have suppression Systems (Which I consider a big mistake). Which means that the battery fire may be over after much less than 5 minutes but by then other flammable material will have caught fire and keep burning. The hint is in the smoke in those instances. LiIons create very little smoke when burning. Copious amounts of smoke indicate that other stuff has caught fire.

Airclues

A thermal runaway in a lithium ion battery can be induced by either a heat source or a short across the terminals. Once one battery overheats it will induce a thermal runaway in other batteries close by.
This is the reason that there are strict rules about the carriage of these batteries. Some types of battery are CAO (Cargo Aircraft Only).
Having undertaken practical training in dealing with lithium ion battery fires, I doubt that this is the cause of this tragedy. These batteries are extremely explosive when in a state of thermal runaway so I doubt that the aircraft would continue to fly for several hours after the event.

RichardC10

The ICAO report analysis shows that routes can be generated from the start point to the final ping arc at a variety of speeds that are not impossible. Once a start point and a speed are selected there is only one choice for the Southern route (at least a route that has a chance of being close to the BFO data). I get speed changes of between 6 and 16degrees/hour for the first four route segments (a fit the red zone) and 1degree/hour for the 22:41-00:11 segment; the path looks roughly consistent with the report maps (figure 1). I get a slightly lower speed (311 against 323kt in the ICAO report) – the report analysis would have used wind corrections, I did not. Anyway, the precise route does not matter, the key issue is the BFO at the final ping arc(s).

Figure 1: Fit to the ICAO report start point and red-zone using a constant speed route of 311kt. To be clear this in not intended to prove the aircraft went to the red zone
Example Fit To The Positions In The ICAO Report Using A Constant Speed Course Of 311kt. Is Not Intended To Show That The Red-zone Is Correct Photo by RichardC10 | Photobucket

Red/yellow/green zones meaning: In the report map the 00:11 markers for speeds 323, 332 and 344 are marked with 30000, 15000 and 3000ft respectively. The ping-arc data is very slightly sensitive to the absolute height and the BFO not at all sensitive, so if heights has been used in these plots it must have used a change of height in the modelling. Also, if the fuel was exhausted at 00:18, flying at 344kt/3,000ft would not give a longer range than 323kt/30,000ft so these values are not height for the whole route. The rate of climb/descent is part of the overall Doppler due to the aircraft's own motion and is not corrected by the on-board system (as is clear by the change of BFO at 1710UT in the original Inmarsat graph - top of climb). So if the aircraft was descending at 00:11 the BFO value at the final ping arc would have been changed, giving a lower value.

The red-zone track states a final height of 30000ft, so no descent. The required descent rate for the 344kt track at 00:11 (green zone) to bring the BFO value back to that predicted for the 323kt track (red zone) is 230ft/min (4.2Hz in BFO). That would give a change of height of 21000ft in the 1.5hrs between 22:41 and 00:11, so compatible with the difference between the supposed height of 30000ft at 22:41 and the marked 3000ft at 00:11. Presumably work in the simulator has indicated some basis for this.

So in summary, the hypothesis:

a) The final BFO data (which we do not have – we have only the initial set released to the families) is a fit to the Red Zone.

b) The Red, Yellow and Green zones refer to possible rates of descent after 22:41. The red zone is the best match to the (assumed) 00:11 data with the aircraft level at 30000ft. If the aircraft was descending at 230ft/min the green zone would be the best match to the 00:11 data. It is taken here that some work on the aircraft analysis has given a basis for this.

c) This explains why there is no green or yellow zone North of the red zone. The aircraft is not expected to climb from 30000ft, so the BFO cannot be changed to deflect the final position North.

Again, here I am trying to understand the presented analysis, not offering some alternate model.

threemiles

Thanks, RichardC10, great analysis.

To be resolved for me remains:

- flight was well above F300 at MEKAR, otherwise no radar contact from Butterworth was possible. It should have made good GS 460 kts from IGARI to MEKAR, otherwise times do not work.

- GS of 311 to 340 kts, needs a lower level to stay above minimum clean ; or non-clean flying; or circling; too low level would reduce range significantly (people with 777 flight manual will tell)

- the curved track cannot be flown with autopilot in HDG mode as magnetic variation is not consistent (maybe with any lateral mode off?)

RichardC10

The report analysis does not require a 'curved' track, that is to say a continuous turn. As I noted, the rate of change of heading (averaged over each leg) is not constant so each leg just averages to a heading. Small heading changes make little impact on the average speed over that leg so do not invalid the analysis.

All the way through the AMSA/JACC maps, the possible tracks have been labelled with speeds, implying an assumption of constant speed (but not heading).

So, the following speculation (and I know nothing about B777s so this bit could be gibberish).

a. The analysis (after the turn) is based on the autothrottle being engaged, but at an unknown speed.
b. There is no heading autopilot maintenance mode engaged and the aircraft heading is wandering left and right, but with a general trend to the left which reduces with time during the flight.

threemiles

Thanks, Richard,

a. (N1 selected) and b. are the same assumptions I made.

Ian W

For those waxing poetic about Lithium Ion batteries, you have not traveled in an aircraft in the last 5 years that has not had tens of lithium ion batteries in the aircraft hold and passenger cabin. Even the Cathay Pacific rules upthread would allow 2 extended life laptop batteries (random packed by pax with cables and USB drives) in their checked bags - so in a widebody you have the potential for several hundred of these. And there HAVE been fires in the passenger cabin due to laptop fails.

Now as also said you have to come up with a practical way that a fire in the hold that would immediately trigger an alarm in the cockpit, could stop ACARS, SSR transponder and the three independent VHF radios in the short period of a simple change of frequency usually by selecting the 'other box' - without any distress call from the crew.

This would be a really severe fire.

Yet the aircraft flew a zigzag course across the Malaysian peninsula around the top of Indonesia and then flew South for another ~6 hours with continuous power to the SATCOM equipment.

So apply a modicum of logic to these theories.
I also second the idea of moving the detailed discussion on 'safety of LiIon Batteries' to the Tech Log in a new thread as it seems to excite 'heated reactions' in some posters here.

wiggy

Richard

The team may correct me but I think that with a serviceable 777 autopilot engaged you're always going to have some form of "firm", non random non wandering lateral mode, even if it's as basic as some variation of attitude hold.

Sheep Guts

Ian W,
You are quite right About 3 different VHF sets and obviously there are 3 different antennas for these radios and different power Buses aswell. But how are the coaxial connections and coax run through the airframe to these antennas? That's what we don't know unless we have some B777 Avionics guys out there to tell us. If there are wire bundles or coax bundles, that could have been severed simultaneously because they were collocated .If that's been discussed and answered before please forgive me.

I agree with your "Lithium Ion phobia"synopsis. We have been flying many Lion batts for years. And it will only increase with the proliferation of Lithium Ion power sources and applications. That's why rules of carriage for the items need constant adjustment as new technologies are used. It needs to be proactive rather than reactive.

UNCTUOUS

If the favoured theory is fire being the cause of the MH370 disappearance, I'd tend towards a known quantity, the cockpit oxygen fire - rather than the Lithium Ion battery cargo-fire. From the SAA's ZS-SAS (the Helderberg) Nov 87 downing onwards, all instances of Li Ion fires have tended to be self-sustaining and progressive, in particular those with large quantities of batteries - whether containerized or not. MH370 was carrying two metric tonnes of them. The Helderberg 747 Combi was carrying a large quantity of Li Ion watch batteries in its aft cargo compartment. Worthy of note is that its self-sustaining fire ate its way through the container and aft cargo compartment bulkhead into the forward pax area over a number of hours, enabling the crew to communicate their plight and inability to locate or quell the fire.
South African Airways Flight 295 - Wikipedia, the free encyclopedia

By comparison, the known quantity and prior experience of a 777 cockpit oxygen fire would:

a. make the flight deck more or less instantly (or at least quickly) uninhabitable due to intense heat and flaring (F/O's side first most probably).

b. alarm the flight-crew immediately to the extent that they would understandably misinterpret it as an electrical fire (thinking uppermost of Swissair 111 pilot errors of plodding through a lengthy checklist that kept power on the wires)....and they'd quickly start monitoring off all non-essential busses (quickly followed by flight essential busses - thus killing the comms and transponder). I'd guess that soon after the aircraft rolled out on its pilot-selected heading for Pulau Langkawi, all aboard could have expired - due to the limitations of cabin drop-down oxygen and the inability of the pilots to regain the cockpit and initiate or hasten any descent. The fact that MH370 did roll out on heading would tend to suggest that the autopilot was still functioning.... at least up to that point. Forget all priorities of aviate/navigate/communicate in any such instantaneous development. Personal survival would understandably be the paramount concern for the pilots. You cannot operate in an inferno.

c. An oxygen fire would burn out quite quickly with damage limited to very adjacent and localized equipments and control panels only (example being the early 1980's cockpit fire that destroyed the cockpit of P3B Orion A9-300 on the ground at RAAF Base Edinburgh South Australia). That fire was due to oil-induced combustion (not a chafing of electrics) and it was initially intense but not persistent or self-sustaining. After the initial flash-fire subsided, it simply smouldered. An airborne fire that pierced the 777's cockpit side-wall would have allowed any smouldering to quickly self-extinguish, even permit a surviving pilot to revisit what remained of the flight-deck.

d. An oxygen-based cockpit flash-fire would cause a rapid depressurization at Flt Lvl 350 due to hull burn-through - and consequent unconsciousness and death from hypoxia of all aboard. The piercing of the hull would tend to extinguish any interior fire.... but manual control via yoke may not have been an option (see photo below).

e. Pilots would have / may have found it necessary to quickly abandon the cockpit. Even if they made it to a portable oxygen bottle, it's a dubious proposition that they would have been able to return to and man the flight deck (let alone manually fly the airplane). They may have been later able to operate or restore some systems and even initiate a descent.

A Li Ion battery-initiated fire just doesn't fit the bill for the rapidity of known events aboard MH370. But it's logical that an oxygen flash fire (oxygen-fed only to the extent and so long as the cockpit oxygen pipes and pressure-hull remained intact) would be about the only other non-hijacking explanation for the instantaneous cascade of issues that led to the sudden loss of comms and squawk and the protracted MH370 ghost flight. Whether or not the pilot (or someone?) regained the cockpit and restored some electrics, selected a waypoint, autopilot etc after the fire subsided? Maybe, but depends on numerous factors. However the aircraft (due to its active controls and inherent stability) would still have been capable of autopilot-off flying a roughly sustained heading and tending to climb back up to height as fuel burnt off over the next six hours - due to its static trim state. Southbound and with a hole below the RH cockpit window might explain the Inmarsat-derived gradual arc to its right (i.e. due slight drag-induced asymmetry). Pilot(s) may have sustained fire injuries that caused one or both to succumb or to be unable to sustain themselves with portable oxygen bottles. The possibilities are many - but the plausibility for an oxy fire is intact.

Final Rule was only released by FAA a few days ago (the initiating ramp incident was in Cairo to an Egyptair 777 over three years ago).
"We are adopting a new airworthiness directive (AD) for certain Boeing Company Model 777F series airplanes. This AD was prompted by a report of a fire that originated near the first officer's seat and caused extensive damage to the flight deck. This AD requires replacing the low-pressure oxygen hoses with non-conductive low-pressure oxygen hoses in the stowage box and supernumerary ceiling area. We are issuing this AD to prevent electrical current from passing through an internal, anti-collapse spring of the low-pressure oxygen hose, which can cause the low-pressure oxygen hose to melt or burn and lead to an oxygen-fed fire near the flight deck.
UNIFIED AGENDA
Airworthiness Directives
1 action from October 2014"




The Most Likely Cause of the MH370 Loss and Ghost Flight)

misd-agin

Even with no A/P engaged the 777 will keep pointing/going/flying in the direction it's going.

Previously posted range impact of lower altitude. Forget the details but it decreases to 60--70%(?) of OPT ALT performance. Endurance is basically unchanged.

Viscount43

Notwithstanding the lith-ion battery issue, I find Unctuous' scenario most plausible........

creeper00

Anyone posting a theory that fire was responsible for what happened to MH370 must also explain how the airplane continued flying for seven hours. When you can do that, I'll believe fire was the cause.

philbky

UNCTUOUS's theory is interesting but I just wonder had the cockpit been severely damaged by an O2 fire, just how stable the aircraft and its control systems would have been.

Certainly any hole in the side of the aircraft would not have initially or later disabled its ability to stay aloft but the control surfaces are fly by wire so the questions have to be asked, in the light of the destruction to the Egyptair example, could the controls remain in a detente position exactly as they were at the time the cockpit end of the system burnt through? How would they cope with turbulence changing any of the axes of the aircraft? If there was time to handle the aircraft to turn it round, why did not the crew call Mayday a la Swissair 111?
How could anyone regain the cockpit and perform any useful function if the damage was as extensive as the Egyptair example and for that matter to the Swissair 111?

Had Swissair 111 suffered its fate an hour or two later we would likely still be looking for it given the hypothesis set out above as it would have been in mid Atlantic with, on the night, not the best HF comms, though the VHF guard frequency might have been used.

My money always has been and still is on a hypoxia situation but, like everyone else, I'm currently lost for a cause that ticks all the boxes.

UNCTUOUS

Creeper00 said:
It's the nature of a flash fire and the characteristics of today's push-button environment. Push that button and things will change. Melt that button and things just won't. It's merely the difference between the "status quo" and "que sera". A flash-fire just sweeps through and fizzles ( if you were a fireman you'd appreciate this distinction).

Just google flash-over or flashover. A flashover, when you unwisely open a door in a burning building, will kill you but it will only scorch the environment.....before subsiding as the combustive differentials in oxygenation are equalized. It's nothing like a fuel-fed fire. That's the nature of an oxygen fire in an enclosed area. While oxygen is feeding, the fire thrives and burning is less apparent than melting (particularly of most plastics). Done any oxy-welding?

Once the oxygen feed is compromised by the low-pressure oxygen hose being destroyed, that low-pressure flow's feed is no longer there past the oxy regulator's internals and so the fire subsides and it is quickly blown out by the slipstream (cockpit sidewall burn-through).

It's as if someone did a single pass through the flight-deck with a flame-thrower. It's a whoosh, lotsa melting and a charred interior. The proximity of the oxy-fed flamethrower to the cockpit sidewall is sufficient to quickly achieve burnthrough. That's why you get that blue flame at the tip of a blow-torch.

Once the fire's out, the systems' status are mostly as was (apart from whatever the pilots initiated in their early event response) .... but later actual actuation of a melted plastic button? Not gonna work again. You're stuck with its original selection.

Got the idea? Novel to you perhaps, but not anyways mysterious to crash investigators.

Try googling NASA the Apollo 1 oxygen fire. It tells a similar story.
P.S. I gave up sucking 100% oxygen after a hard night - once I realized the potential for beard-singeing after eating a greasy hamburger.