July 05th, 2017

MH370: The third and final round.
Welcome back. Here's the rest of the story and I'm sticking to it.

My initial theory had the captain temporarily handing over the flying duties to his F/O sometime between the level off check and the hand off point from Malaysian ATC to Viet Nam ATC. It involved the Captain leaving his seat for a few minutes under the pretext of retrieving some item from his personal luggage stored in the aft spaces of the flight deck. In the dark behind his first officer, he then reached up and pulled the ACARS* circuit breaker. This would’ve triggered a warning followed by a call for a circuit breaker reset procedure and the cancellation of the warning. The Captain, still in place, would’ve then pulled it again. The second time any re-set circuit breaker pops, it is to be left alone for fear of fire etc. So with some slight-of-hand, the Captain surreptitiously disabled the first of several communications systems before returning to his seat and assuming control of the aircraft again. This could be done easily in the B-767—I know exactly where that circuit breaker is—and assumed, incorrectly, that it would be in a similar location in the B-777. After some digging, I discovered that on the B-777 the ACARS could not be shut off from the flight deck, only from the electronics bay located below the floor with the access hatch under the carpet in the forward galley. This made the timing and required actions of the captain nearly impossible and very nearly blew my theory right out of the water.
           But I have discovered (with help from AC B-777 instructor Captain Owen Stewart) that the ACARS system cannot be switched off but it can be disabled on the B-777 without leaving the flight deck. Right at the handoff point between Malaysian and Vietnam ATC, the drama begins. Here’s my possible re-creation and it is actually very simple. I recall a BA (British Airways) captain stating that if there ever was a time to steal an airplane, it would be at the international boundary ATC handoff point between two countries.

*ACARS stands for Aircraft Communications Addressing and Reporting System. It is a fully automatic data linked message sent back to the airline operations control with a set of captured flight and engine performance data. The pilots are not involved in these regular automatic transmissions.

 Timeline: MH370 Communications. All times local.*
1.  1:07 am: Last received ACARS transmission.
2.  1:19 am: Last verbal communication. “All right, good night” from the aircraft; believed to be the co-pilot (F/O).
3.  1:21 am: Transponder stopped transmitting (turned off or failed).
4.  1:30 am: Civilian (primary) radar lost contact.
5.  1:37 am: Expected ACARS transmission; not received.
6.  2:15 am: Last military primary radar contact.
7.  8:11 am: Last (hourly) satellite handshake.
*aviationist.com MH370 timeline

The points of interest from the timeline above are numbers 1, 2 and 5.
           Points 1 and 5 indicate that the ACARS transmits once every thirty minutes. Point 2 shows the last VHF radio transmission occurring eighteen minutes before the next scheduled ACARS transmission.
           The hand-off transmission to MH370 is made from Malaysian ATC, giving the crew the new Vietnam Control VHF frequency. The F/O reads it back, Malaysia confirms that it is correct, and the F/O says, “All right, good night,” to the controller. It’s only a courtesy, common on the radio in the air, nothing sinister about it, and it indicates quite clearly that all was well on the flight deck. While the F/O has his head down dialing up the assigned Vietnam control frequency on his radio, he is interrupted by his captain: “Hang on a minute. Could you do me a favour? I’ve got the radios. I’ll check in with Vietnam for you. Take a break. Go back, stretch your legs for a few minutes, flirt with that beauty in the biz class galley, grab us a couple of coffees and a copy of the Malay Times. I like their sudokus and I take my coffee black.” Or whatever chore the captain could think of!  The F/O leaves his seat to complete his captain’s errand and the flight deck door closes and locks solid as he exits. The captain is now in complete and sole control of the aircraft and all her systems. From here, it’s a simple matter of either disabling the electronic emergency flight deck entrance system by pulling the appropriate circuit breaker or physically dead-bolting the door. Or both. Either way, no one can enter without a cutting torch—rather scarce gear at the time—and the captain is free to put the rest of his plan in play at his leisure.

           First, he turns off the transponder (timeline point 3, just two minutes after the F/O’s transmission) and kills all the aircraft running lights, anti-collision lights, and strobes. Now he’s virtually invisible to both radar and other aircraft.

           Second, he turns off all his radios—VHF, HF and SATCOM—as he had nothing further to say to anyone. This act disables the ACARS by denying it the required transmission devices. The anticipated transmission at point 5 above never occurred.

Third, he activates a stored secondary flight plan in the flight management computer (FMC) that he had previously programmed, perhaps from memory, while on the ground in KL. We used to mess with the secondary flight plan feature all the time, even while in flight. You know—important stuff like how many miles it is from Katmandu to Grandma’s house. But mostly we used it to program the route to our alternate airport to cut the workload should a diversion from our destination become necessary. As long as the primary flight plan was active, nothing would happen unless and until you selected and activated the secondary stored flight plan, at which time the autopilot would begin to follow this new flight routing. This, I believe, is when the sharp turns to headings to the west, the southwest, and the south began. I speculate that the routing had something to do with getting away from civilian ATC radar as fast as possible. But I’m guessing, of course.

           Fourth, he allegedly climbs to 45,000 feet (FL450). This is debatable, as it was both unnecessary and most likely well above the maximum ceiling of the B-777 at that weight so early in the flight. Perhaps he believed that climbing to such an altitude would make it even more difficult for civilian or military ATC radar to spot him. Passenger mobile phones would also be useless and I have since learned why: cell phone towers are not aimed skyward but angled toward the ground because—wait for it—that’s where the phones are. Quite possibly, no passengers knew of any trouble at that time and had no obvious reasons to call regardless.

           Fifth, he reaches up to the cabin pressure controller sub-panel just above his head and starts dumping cabin pressure, rapidly raising the cabin altitude to well above normal.

           Sixth, he puts on his own flight deck oxygen mask.
           As the cabin altitude climbed above 10,000 feet pressure altitude, the passenger masks would have automatically deployed. These supply just ten to fifteen minutes of oxygen to the passengers, just enough time to allow the flight crew to don their own masks, declare an emergency, and steeply descend to an altitude where it is safe to breathe without them. This descent to safety was never intended and never happened. After twenty or thirty minutes at a pressure altitude of, say, 30,000 feet, it can be assumed that the F/O, flight attendants and passengers, if not already unconscious or incapacitated, were struggling for their lives, using whatever oxygen, portable or otherwise, was available. The passenger oxygen would’ve run out by then. Regardless, the passenger cabin would’ve been chaos until the inevitable. Pleadings by the F/O to be allowed entry to the flight deck were ignored. (Author’s note: As were the dreadful recorded pleadings of the German Wings captain through the flight deck door to his own F/O as that aircraft descended to its doom in the Alps.) Most would finally just go to sleep and succumb to hypoxia even as they tried to contact the captain. He was in no hurry. He had all the oxygen he needed.
           As an aside, the time of useful consciousness (TUC) for an average human at a pressure altitude of 35,000 feet is thirty to forty seconds .(The term is time of USEFUL consciousness—you’re still conscious, but you are losing your faculties VERY quickly. You are breathing but the air is NOT entering your bloodstream at that altitude. The next sentence is absolutely correct. After forty-five minutes, most, if not all, on board would be dead.

           The seventh and final act: This is where the captain’s basement simulator may have been useful, even though he didn’t really need it. He only needed the B-777 performance charts and the location of the deepest, most remote part of the South Indian Ocean. We’ll never know either way.
           When the captain was sure that all were dead or otherwise incapable of any interference, he sets his autopilot to do his bidding. He knew how much fuel he had on board and he knew the location where he wanted the flight to end. So he simply created a way-point using the latitude and longitude of his target, entered it into the FMC, made it the “go to” waypoint (it may have already been pre-loaded) and selected “NAV” on his glare-shield control panel. The autopilot would now take the aircraft directly toward his target. Or he could’ve used “Heading Select.” Setting an aircraft heading of 180 degrees true will point you straight at the world’s geographic South Pole, no matter where you are.
           But how could he plan the impact point? This is where the performance charts come in. At a given speed, altitude, and temperature, the aircraft will burn “x” pounds of fuel per hour per engine, which increases if the aircraft is flown at a lower altitude and/or at a higher Mach number. He makes his target the “tanks run dry here” point and works backward. He calculates that, at a certain altitude and speed/power setting, the fuel he has remaining will be exhausted roughly over his target. So he simply sets the desired altitude in the altitude select window, the speed in his speed select window, the rate of descent to the selected altitude, and hands it all to the autopilot. When satisfied that the autopilot is doing as ordered, the captain removes his own mask (or perhaps takes a suicide pill of some kind), and goes to sleep. The aircraft dutifully descends to the chosen altitude (low twenties perhaps?) and flies for hours into the southern reaches of the Indian Ocean at the selected speed, burning up the remaining fuel with no one on board alive.
           On the B-777, the cockpit voice recorder is a two-hour self-erasing loop. If ever found, and with recoverable data, the investigators would most likely listen to two hours of engine and flight deck air noise and nothing else. The flight data recorder would be equally useless, revealing only that the aircraft performed beautifully and exactly as programmed until fuel exhaustion and impact.
           Many believed that huge pieces would be recovered. How can such a large bit of machinery disappear so completely? I asked myself the same question (similar to when we heard “The towers are gone!” in the van in Denver on 9/11), but it’s easier to imagine the disappearance when one pictures a near vertical B-777 hitting the ocean doing somewhere between 400 and 500 knots. The aircraft would very nearly vapourize from the astronomical impact forces.
           Many also believe that when an airplane in level flight runs out of fuel, it will just glide down gracefully and pancake onto the surface. This might happen for airplanes not in autopilot “altitude hold” mode. For an aircraft flying in this mode though, it’s a different story. When the fuel is exhausted, the engines stop—first one, then the other (they never stop at the same time). As long as the electrical and hydraulic power lasts, the autopilot will keep doing what it has been asked to do for as long as it can do it. Even with the temporary asymmetric thrust problem, the autopilot will try to maintain the assigned altitude and track. When both engines quit, the airspeed starts rolling back. Because the autopilot is trying to maintain altitude, it begins to increase the pitch angle (raise the nose) in order to generate the lift required to maintain the selected altitude at a lower airspeed. More pitch equals more drag, causing the airspeed to roll back even faster. I’m willing to bet that, in less than thirty seconds from the second engine quitting, the aircraft had already started its death roll and plunge to the ocean. One wing always stalls before the other. The autopilot by now had thrown up its hands and disconnected—its limits exceeded. With no pilot alive on the flight deck to initiate a stall recovery, that huge machine would’ve rolled on its side as the first wing stalled, its nose falling to near vertical, and gravity would have done the rest, rapidly accelerating it to extremely high speeds, ensuring complete destruction on impact in one of the most remote stretches of ocean on earth. The flaperon found near Africa may have ripped off during the ferocious descent, tumbling and slowing down as to remain intact on impact.
           So that’s it. No bloody violence and no conspiracies, on-board or otherwise. A single dead villain and an airplane full of innocent dead passengers and crew that slammed into the Indian Ocean, disintegrating and sinking to the depths. More pieces may be found on various beaches around the Indian Ocean. Investigators may connect some of the dots, but in my humble opinion, this simple but plausible scenario I’ve just presented is the most likely.

Until next time, over ‘n out.