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Flt 370: A Speculative Scenario

John Duncan

Apr 03 2014

9 mins

boeing goingSpeculation has been rife on what happened to Malaysian Airlines flight MH370 in the early hours of Saturday, March 8, and why it may have ended up in the Southern Indian Ocean.  While a variety of scenarios has been mooted, the available evidence — such as it is — suggests an onboard fire as the most likely explanation.

Start with a credible report by Mike McKay, a New Zealander working on an oil rig off the coast of Vietnam, whose eyewitness report seems to have been overlooked:

“I observed (the plane?) burning at high altitude at a compass bearing of 265* to 275* from our surface location [co-ordinates given].  It is very difficult to judge the distance but I’d say 50-70km along the compass bearing 260 – 275. …

While I observed the burning plane it appeared to be in one piece.

From when I first saw the burning (plane) until the flames went out (still at high altitude) was 10-15 seconds.  There was no lateral movement, so it was either coming towards our location, stationary (falling) or going away from our location.

The general position of the observation was perpendicular/south-west of the normal flight paths … and at a lower altitude than the normal flight paths.  Or on the compass bearing 265 – 275 intersecting the normal flight paths and at normal altitude but further away.”

His confusion about altitude and distance is understandable, given that the night sky deprived him of visual reference points.  Against a black sky, a plane, in flames or otherwise, might actually be much further away than it appears to the unaided eye.  Several precedents lend plausibility to this scenario.

On the evening of September, 1998, Swiss Air flight SR 111, a McDonnell-Douglas MD-11, departed New York for Geneva via the shortest route, an arc that would take it up the east coast of the USA then across the Atlantic. About an hour into the flight smoke entered the cockpit through the air conditioning duct and the pilots requested an emergency  landing at the nearest airport, Halifax in Nova Scotia, just 65 nautical miles distant.  The plane quickly lost height from 33,000 feet, descending in a large spiral.  Taking their plane over the coast to dump fuel as they descended,  the pilots banked into the  sea, killing all 229 people aboard.

The five-year investigation by the Transportation Safety Board of Canada [1] concluded in 2003 that the fire was started by a short-circuit in electrical cabling in the ceiling space immediately behind the cockpit — a fire made more intense by flammable thermal and acoustic insulation.  In particular, it was noted that oxygen-feed pipes likely failed, added air and/or oxygen to the fire and at the same time deprived the passengers or crew.

Aspects of this accident may well be pertinent to the fate of MH370. In swift succession, the auto-pilot and primary flight-control computer failed, as did most instruments. Of particular significance, perhaps, is the investigators’ conclusion that, over the next few minutes, the flight transponder also became non-operational; so, too, the  pilots’ display units,  the VHF radio, the cockpit voice recorder, the flight-data recorder and one of the plane’s three engines. The implication is that system failures need not happen simultaneously if dependent on different power sources.  Suspicions that MH370’s devices were deliberately powered off are, therefore, not necessarily true.

The Boeing 777 boasts a very good safety record, with only one fatal accident — an Asiana Airlines which came to grief at San Francisco Airport in July, 2013, not as a consequence of mechanical failure but due to pilot error.  Two passengers died, 181 people were injured and 123 escaped unhurt after a fire broke out on the ground.

On February 18, less than three weeks before MH370 disappeared, five separate fires were lit in lavatories on an Etihad flight EY461 from Melbourne to Adu Dhabi.  After two of those fires had been extinguished by the cabin crew, the aircraft diverted to nearby Djakarta, where passengers and their luggage were searched but no arsonist identified.  Cigarette lighters and matches were confiscated before the passengers were allowed to re-board, but three more fires were lit prior to arrival in Abu Dhabi, including one over the Indian Ocean.

Flight MH370 departed from Kuala Lumpur at 12:21 AM and headed north, reaching its cruising altitude of 35,000 feet somewhere near the northern coast of Malaysia.  It was equipped with five radios and two transponders, and the aircraft communication addressing and reporting system (ACARS) was operating.

At 1:19AM the pilots signed off from Malaysian Air Traffic Control and passed into the airspace of Vietnamese air traffic control.  Malaysia’s Acting Transport Minister Hishammuddin Hussein has said the ACARS system was deactivated even before the voice sign-off.

When Vietnamese ATC hadn’t heard from the plane by 1:30AM it asked other pilots in the area to attempt contact.  One pilot about 30 minutes ahead did so and reported making a contact that contained a lot of static and “mumbling” from MH370, from someone that he took to be the co-pilot.  That was the last signal heard from the aircraft.

I believe that a fire may well account for this — a fire perhaps started deliberately, as happened repeatedly on the Eithad flight, in or above the lavatories at the front of Business Class.  Once in the ceiling space, the flames rendered inoperable various pieces of equipment and the electrical cabling that supplied them.  Back-up equipment is of little use if connected to the same, disabled electrical circuits. Such a fire would account for the series of equipment failures over a period of time, whereas a bomb or similar catastrophe could be expected to disable all at a stroke. Similarly, if hijackers had taken control of the aircraft, they could have been expected to shut down all systems more or less simultaneously, rather than pausing for  irregular intervals before switching off the next system. If we accept that the ACARS system was rendered inoperable just prior to the 1:19AM sign-off to Air Traffic Control, the likelihood is that the pilots were as yet completely unaware of a fire raging above and behind them.

The pilots’ visual displays probably reported the ACARS failure, but such an alert would probably have been regarded, at least initially,  as nothing critical, as radio-transmission failure is nothing extraordinary for the airline industry. The back-up system could be switched on and, in theory, all would be fine.

When flight computers started to fail it would have been a different matter.  In trying to report the problem the pilots would have discovered that all their radio systems had gone down.  At this time, there would also have been a bedlam of erupting cockpit alarms, swamping the harried pilots with an overload of information.

Quite possibly the plane turned left at this point as a preliminary for a return to Kuala Lumpur. My strong surmise is that, around this time, a ceiling panel collapsed in Business Class, raining burning material into the cabin and sending terrified passengers dashing toward the plane’s rear.  In doing so they would have obstructed cabin crew moving forward to assist.  Another problem would have been the sudden shift in weigh distribution toward the plane’s tail. Under normal circumstances the pilots could have responded by adjusting the aircraft’s trim, but they were probably fully occupied at the time and might not have noticed that, with the tail pushed down, the aircraft was rising.

I surmise that the fire was extinguished by a rupture to the top of fuselage, much as happened to the Asiana Boeing when it burned on the ground in San Francisco. The cabin crew near the fire would not have been wearing seat belts and, like other passengers not wearing seat belts, were likely sucked out of the aircraft. Quite possibly this would have included Captain Zaharia who, like the SwissAir pilot, left his seat and the plane in control of his co-pilot while he went to  investigate rather than rely on intercom reports from the cabin crew.

The rupture of the fuselage would have starved the fire of oxygen, also depriving passengers until oxygen masks dropped automatically from the ceiling. The further complication, if this is what transpired, is that there would have been insufficent masks to accommodate refugees from Business Class.

But oxygen wasn’t the only problem.  The outside air temperature at that altitude would have somewhere in the vicinity of -40C.  No-one aboard would have been dressed to survive those kinds of temperatures, and the thin blankets onboard would have been next to useless.

The pilots or pilot — if either caption or first officer had left the cockpit for the cabin — would have had little choice but to put the aircraft into a steep descent into warmer, oxygen-rich air.  Due to the smoke, he would have been wearing his oxygen mask, and the cockpit door offered some protection against the sudden temperature drop. Whoever was the controls would have realised urgent action was required.

The plane has been reported as being as high as 45,000 feet — and then at around 5,000 feet.  Even if it had descended at 10,000 feet per minute that’s four minutes of intense cold the passengers would have had to bear, which is probably unsurvivable.

With passengers and other aircraft crew killed by the fire, asphyxiated by smoke and fumes, done in by sudden decompression or frozen to death, the pilot or co-pilot may well have been the only survivor aboard, albeit one likely to have been injured and struggling with his crippled plane.

With radios and most flight instruments out of action, best option was to return to familiar Malaysian airports, which also were the closest, where he could probably land from visual bearings. He had a compass but couldn’t know his exact position and, therefore, would have had to rely on sightings of landmarks.

We know the plane crossed the Malaysian coast near Kota Bharu, in the northwest. Then, somewhere near the west coast, turned slightly to the south, possibly with the intention of dumping fuel over the Strait of Malacca and to position the aircraft in line with runway 14R at Kuala Lumpur International Airport.

If the surmised flight direction is correct it was about this time that whoever remained in the cockpit continued on its pilotless flight on a compass bearing that would take it across Indonesia and, eventually, to its likely splash down some 1800km west of Australia.

All of the above is speculation rooted in information gained from previous air disasters, but it fits with the known facts. Consider:

  • Transponder communication failed at a different time to voice radio.
  • The Boeing was reported as being on fire,
  • It diverted from its flight path to briefly fly to the northwest and then, apparently, to the southwest;
  • It reportedly climbed above its normal cruising altitude, then descended to around 5000 metres,
  • If the above facts and deductions arte valid, it flew on a constant heading for its final five or six hours before crashing into the Indian Ocean .

SwissAir flight SR111, on which much of the above speculation is based, crashed into the ocean and sank in about 200 metres of water, when some million-plus pieces of debris and body parts were recovered.

MH370 is supposedly off the Western Australian coast where the water is over 4000 metres deep.  Speculation might be the best we can do.

 

[1] http://www.tsb.gc.ca/eng/rapports-reports/aviation/1998/a98h0003/01report/index.asp

 

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