Category: Aviation

by Victor Iannello

[Note: While attention has been focused on the definition identification of the Reunion flaperon, there remain many other elements of the MH370 case that still require careful attention. Here, Victor delves into what the data that has been released, in particular in the Factual Information (FI) report, to clarify what we know about the first hour of flight after the turnback at IGARI. — JW]

Summary

This work analyzes the position and time data derived from the publicly-available radar data for MH370. Some of the findings are:

• After the turn back towards the Malay Peninsula, the flight path recorded by civilian primary surveillance radar (PSR), civilian secondary surveillance radar (SSR), and military radar are consistent with a flight at a Mach number (M) equal to 0.84 at an altitude of FL340.
• If the aircraft did fly at a steady M = 0.84, then the timestamps for some of the PSR contained in the Factual Information (FI) are offset by about 35 s.
• After the left turn at around 17:23:38 UTC, the aircraft might have descended from FL350 to FL340 and accelerated from a ground speed of 473 kn to a ground speed of greater than 500 kn.
• In the FI, the PSR data between 17:47:02 and 17:52:35 UTC is attributed to the radar site at Kota Bharu, but more likely was collected by another radar site. The PSR data between 17:30:37 and 17:44:52 is correctly attributed to Kota Bharu.
• In the FI, it is stated that Indonesian military radar recorded MH370 as it traveled toward IGARI but not as it traveled back over Malaysia. One explanation is that Indonesian radar site was powered down after midnight, local time.
• The sharp turn to the left at around 17:23:38 UTC is unexplained, and could be due to either an inaccurate graphical portrayal of the radar track, or crossing radar tracks from two aircraft.
• The curve in the radar path close to Kota Bharu can be explained by “slant range” due to high altitudes and close distances.
• The fuel consumption models which assume that MH370 flew near Long Range Cruise (LRC) speeds and at cruising altitudes between 17:07 and 18:22 are likely accurate.

You can read the whole document here.

Seriously, why? Can anyone think of a single justification?

The plane has a fully functioning communications suite, so if your plan was to commit suicide but then you got cold feet, you could call for help. Otherwise, what you’re looking at a best-case scenario in which you wind up sitting on a slowly-sinking aircraft for a little while until you wind up treading water until you drown or get eaten by sharks.

And you’d have six hours beforehand to do nothing but sit there and think about what lay in store.

It’s not every day that you need to talk to one of the world’s leading experts on goose barnacles of the Indian Ocean, but today is one of those days, so I considered myself very fortunate to get in touch with Charles Griffiths, an emeritus professor of marine biology at the University of Cape Town and author of the seminal paper “South African pelagic goose barnacles (Cirripedia, Thoracica): substratum preferences and influence of plastic debris on abundance and distribution.”

I reached out to Dr Griffiths by email and he graciously answered my questions about the sea life found growing on the Reunion flaperon after I sent him a more detailed version of the picture above.

Is it possible to identify the species of barnacle growing on the debris? 

In this case it is possible to identify this as being Lepas anserifera striata on the basis of the small row of pits across the shell, which is characteristic of that subspecies.

Can this tell us anything about where the debris might have been floating?

This is not much clue as the species has a wide global distribution in tropical and subtropical seas.

Can you say in very rough terms how long it takes the barnacles to reach this stage of growth?

I cannot accurately gauge the sizes of the largest specimens from the image but goose barnacles grow spectacularly fast e.g. 21 mm head length ( i.e. Without the supporting stalk) in 21 days cited in one paper I have at hand. I have seen very large barnacles (as long as my finger) growing on a cable known to have only been in the water for 6 weeks!

UPDATE: To clarify a point raised by commenters, I asked Dr Griffiths a follow-up question:

Is it true that barnacles can’t survive in the open ocean? Is it possible for a piece of debris floating far out to see be colonized by Lepas anserifera, or would it need to be in a coastal environment?

No, that is not the case. These goose barnacles are in fact characteristically oceanic beasts and only occur in floating objects in the open sea. Reaching the coast is in fact a death warrant for them and any that get washed up die! Interestingly they seem to know whether an object is floating, so for example are common on kelp that is uprooted and floating but never occur on the same kelp when it is attached.

Can you tell whether the barnacles in that picture are alive or dead? If alive, how long can they live after being washed up?

If you find a washed up item that is fresh (same day) the barnacles will still be opening their shells and waving around their cirri (legs) to try to feed. Obviously in a still image cannot see this. However I can see the cirri projecting from some animals. These would rot away and drop off in a few days in a tropical climate, so this wreckage has only been washed up a couple of days at most. Also crabs and other scavengers love to eat goose barnacles and will clean off most within a couple of days. There is no evidence of feeding damage or headless stalks here, so that suggests to me this wreckage was collected and photographed within a day or two of stranding.

Two weeks ago, I wrote a couple of posts about the strange reboot of MH370’s satcom system that occurred shortly after the plane disappeared from primary radar, and asked if anyone could come up with a reasonable explanation. I drew attention in particular to the left AC bus, which the satcom equipment is connected to. This bus can be electrically isolated using controls located in the cockpit, and this appears to be the only way to recycle the satcom without leaving the flight deck. I suggested that there might be some other piece of equipment that the perpetrator wanted to turn off and on again by using the left AC bus, thereby causing the satcom to be recycled as an unintended side effect.

The readers rose to the occasion. Gysbreght pointed out that paragraph 1.11.2 of Factual Information states that “The SSCVR [Solid State Cockpit Voice Recorder] operates any time power is available on the Left AC transfer bus. This bus is not powered from batteries or the Ram Air Turbine (RAT).”

This is an incredibly interesting observation. Reader Oz fleshed out Gysbreght’s insight, writing to me via email:

We could isolate the Left Main AC by selecting the generator control switch to OFF and the Bus Tie switches to OFF; SATCOM is now dead.  What else happens……….the Backup generator kicks in automatically to supply the Left Transfer bus. Here’s what’s so spine chilling; if you now simply reach up and select the Backup Generator switch to OFF………..you now lose Left transfer as well.  The CVR is gone!  I couldn’t believe how easy the CVR was to isolate!
To recap;
Left Gen Control to OFF
Bus Ties to OFF (Isolate)
Left Backup Gen to OFF.
I now firmly believe your mystery reboot was Left AC power being switched back ON……….. after something that had occurred that the perp or perps didn’t want any possible evidence of on the CVR……whatever was being hidden was done by around 1822; AC back to normal.

Gysbreght notes that the Factual Information also identifies the location of the CVR as Electronic Equipment Rack, E7, in the aft cabin above the ceiling, and suggests: “Later [the perp] could have opened Electronic Equipment Rack E7, physically pulled the SSCVR power supply plug from its socket, and then gone back to the MEC to restore power to the Left AC bus.”

Oz has his own theory: “If you are thinking why the hell you would turn Left AC/Left transfer back on? Flight deck temperature control comes from these…”

There’s a precedent for a suicidal airline pilot depowering the black boxes before flying a plane into the ocean: the pilot of Silkair Flight 185 appears to have done just that before pointing the nose down and crashing in December, 1997. It’s easy to imagine Zaharie reading the accident reports and realizing he should also figure out a way to disable the CVR before implementing his suicide plan. When the moment came, near IGARI, one can imagine the veteran 777 pilot suddenly flipping various switches while the baffled newbie, Fariq, looked on.

It’s certainly an intriguing scenario, but it is not without its flaws. As Gysbreght notes, “I would expect the Captain to know that the CVR only retains the last two hours and overwrites older recordings.” So if Zaharie planned to commit suicide by flying the plane for hours into the remotest reaches of the southern ocean, he wouldn’t have needed to turn the CVR off: the portion between 17:07 and 18:25 would have been erased anyway. This is not in insurmountable problem, however. Maybe he orginally intended to crash right away, a la Silkair, but then lost his nerve.

I’m not quite ready to declare, as Gysbreght has, “Case closed,” but I have to admit that the CVR idea is fascinating. Great work, Gysbreght and Oz!

The discussion prompted by last week’s blog post raised some interesting issues that I think are worth discussing in further detail.

First, I wrote last week that “At 18:22, MH370 vanished from primary radar coverage over the Malacca Strait. Three minutes later—about the amount of time it takes the Satellite Data Unit (SDU) to reboot—the satcom system connected with Inmarsat satellite 3F-1 over the Indian Ocean and inititated a logon at 18:25:27.”

Commenter LouVilla earlier today laid out the issue with more clarity, writing:

MH370 flew out of radar range @18:22.12 UTC. All of a sudden @18:25.27 UTC, the AES sent an Login-Request to the satellite. This are 03:15 Minutes between this two events. When the AES is without power supply for a while and reboots after power is available again the AES needs approximately 02:40 Minutes to sent an Login Request (ATSB Report Page 33). 03:15 minus ~ 02:40 = ~ 35 seconds. So, the perpetrator must activated the left bus again at around 18:22.47 UTC, 35 seconds after MH370 flew out of radar range.

The close sequence of these events does, in my mind, raise the possiblity that they are connected. How would a perpetrator know that he has left radar coverage? Among the possibilites would be a) some kind of radar-energy detector (like that used by automobile speed-trap radar detectors) brought on board by the perpetrators, or b)  prior scouting by allied agents. This latter idea would be far fetched for a suicidal pilot but quite feasible for, say, Russia, which spends quite a lot of time probing the radar coverage of its NATO neighbors.

Of course the timing might just be a coincidence.

A second point I’d like to address is the idea that Zaharie or Fariq might have de-powered the satcom by isolating the left AC bus. One problem with this scenario, as I’ve previously mentioned, is that it would be difficult for a pilot to know just what else they would be taking off line in isolating the left AC bus. I later realized that I had underestimated the problem.

Continue reading The Mysterious Reboot, Part 2

In yesterday’s post I argued that the reboot of MH370’s satellite communications system at 18:25 is a key piece of evidence about what happened to the missing plane. In fact, I would go so far as to say that we should discount any scenario which cannot explain the reboot.

That being the case, I thought it would be a good idea to clarify what we do know about rebooting the satcom and discuss the implications. Right up front I’d like to emphasize that I am by no means an electronics expert and I welcome any corrections or clarifications.

First, some basic background for those who might be new to the discussion. Flight MH370 took off from Kuala Lumpur International airport at 16:42 UTC on 3/7/14 bound for Beijing. At 17:07:29, the plane sent an ACARS report via its satcom. At 17:20:36, five seconds after passing waypoint IGARI and a minute after the last radio transmission, the transponder shut off. For the next hour, MH370 was electronically dark. The next ACARS transmission, scheduled for 17:37, did not take place. At 18:03 Inmarsat attempted to forward an ACARS text message and received no response, suggesting that the satcom system was turned off or otherwise out of service. At 18:22, MH370 vanished from primary radar coverage over the Malacca Strait. Three minutes later—about the amount of time it takes the Satellite Data Unit (SDU) to reboot—the satcom system connected with Inmarsat satellite 3F-1 over the Indian Ocean and inititated a logon at 18:25:27.

The question is, by what mechanisms could MH370’s satcom have become inactive, then active again?

Continue reading The Mysterious Reboot

Until fairly recently, the default assumption about MH370 is that, based on the interpretation of satcom signals recorded by Inmarsat, the plane made a final turn to the left sometime after 18:25 UTC and flew south on autopilot before running out of fuel. This default scenario, sometimes referred to as the “ghost ship” scenario, was endorsed by both the ATSB and the Independent Group.

However, if the plane flew south in this manner and ran out of fuel, it would have been found by now, as Brock McEwen explained here recently. It was not found. Therefore the default scenario is incorrect: the plane did not make a final turn and fly straight to the south without human intervention.

At this point, only three possible scenarios still make sense for MH370:

1. As was first mooted in the June ATSB report, the plane lingered near Sumatra before flying straight or took a curving path to the south. In either case, the plane wound up intersecting the 7th arc somewhere north of Broken Ridge, beyond the current search area.
2. The plane flew straight south after a final major turn, then was hand-flown by a conscious pilot on a long glide that took it far from the 7th arc, beyond the current search area.
3. The plane did not go south at all. If this is the case, then the satellite communications system must have been compromised by hijackers who either flew the plane north to Kazakhstan or China (if only the BFO values were spoofed) or somewhere else within a huge circle encompassed by the 7th ping ring (if both BTO and BFO values were spoofed).

Each of these options has unpalatable aspects, but they’re all we’ve got.

I would argue that these unpleasant choices can be further subdivided into two categories: inside the cockpit, or outside the cockpit. By “inside the cockpit,” I mean that the airplane was controlled from the flight deck, presumably by either the captain or the first officer; by “outside the cockpit,” I mean that hijackers managed to seize control of the plane either by accessing the E/E bay or hacking in through the inflight entertainment system. The reason I feel we can make this assertion is that only one minute elapsed between the captain calmly saying “Good night Malaysia 370” and the diversion at IGARI. It’s scarcely imaginable that hijackers would have time to breach the fortified cockpit door, overcome the flight crew, and reprogram the flight management system in such a short time. So whoever took the plane had to be either on one side of the door or the other.

The first two of our three options would fall under the category of “inside the cockpit.” They present a number of difficulties: Continue reading Only Three Options Remain for MH370’s Fate

Here’s a video that niftily recapitulates 15 months of search activity into two minutes. It was produced by commenter @orion, aka Dustin Thomas.