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What We Know Now About MH370

It’s been more than six months since MH370 vanished, and in some ways we know no more now than we did in late March: no new clues have emerged, no more data has been discovered.  In a sense, though, we have come a very long way. For one thing, we now understand how many of the “breaking news” developments that occurred in the early days were actually untrue. (There were no wild altitude swings, no “fighter plane-like” maneuvering, and probably no cell-tower connection with the first officer’s phone.) What’s more, thanks no doubt to a drumbeat of public pressure, the authorities have released a tremendous amount of data and provided useful explanations of how that data is being interpreted. And finally, a spontaneous collaboration between technical experts and enthusiasts around the world has provided a trove of insight into avionics, aerodynamics, satellite communications, and a whole host of other topics that collectively shed light on what might and what might not have taken place on the night of March 7/8, 2014.

While a great deal of information has become available, it has not always been easy to find; much of it, for instance, has been exchanged via email chains and Dropbox accounts. For my part, I often find myself rummaging through emails and folders looking for information that I’m pretty sure I’ve seen, but can’t remember where. So what I’d like to do with this post is try to aggregate some of the most basic facts — a set of canonical values, if you will, of the basic data on MH370. Necessarily, some of this data comes with implicit assumptions attached, so as far as possible I’ll try to make these assumptions explicit.

Okay, on to the data. What we know now:

The bedrock data. In the wake of MH370’s data, there were numerous news reports concerning information leaked by anonymous sources from within the investigation and elsewhere that have subsequently been either disproven or inadequately verified. For the purposes of the present discussion, the following are considered the bedrock sources of information upon which our understanding of the incident can be built — the “Holy Trinity” of MH370 data:

  1. Up to 17:21: radio communications, ACARS, transponder, ADS-B
  2. 17:22-18:22: military radar track. This information is of uncertain provenance but has been endorsed by the governments of both Malaysia and Australia. Furthermore, it plausibly connects the prior and following data sets.
  3. 18:25-0:19: Inmarsat data, especially BFO and BTO values. There is some discussion as to how this data is best interpreted, but the numbers themselves are assumed to have been received and recorded by Inmarsat from MH370 via their 3F-1 satellite. The “ping rings” in particular are derived through relatively simple mathematics and should be regarded as established fact unless someone comes up with a specific mechanism by which some other result could be obtained.

Timeline. Courtesy of Richard Godfrey and Don Thompson, here is a basic timeline of MH370’s disappearance (all times UTC):

  • 16:41:43 MH370 departs runway at KUL runway 32R
  • 17:01:14 MH370 flight crew report top of climb at 35,000 feeet
  • 17:07:48.907 Last acknowledged DATA-2 ACARS message sent from plane
  • 17:19:29 Last radio voice transmission
  • 17:21:04 Plane passes over IGARI waypoint
  • 17:21:13 MH370 disappears from air traffic control (secondary) radar screens
  • 18:22 Last primary radar fix
  • 18:25:27 Inmarsat log-on request initiated by aircraft
  • 0:19 Final transmission from aircraft to satellite

A more complete table of values, including the location of the plane at each point in time, can be found here, courtesy of the inimitable Paul Sladen. And Don Thompson has created an impressively detailed breakdown of the sequence of events, with a special focus on radio communications between the aircraft, ground, and satellite, here.

More stuff after the jump…

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Businessweek: How Airbus Is Debugging the A350

Businessweek A350 wingtip smallA few times a month, Airbus Flight Test Engineer Patrick du Ché stands up from his desk, takes off his jacket and tie, walks to the coat rack in the corner of his office, and slips into a set of fire-resistant underwear, a bright-orange flight suit, and sturdy black boots. Then he walks down two flights of stairs and out onto the tarmac of Toulouse-Blagnac Airport in southern France. There, rising above a fleet of newly painted A320 short-haul jets, is an Airbus A350-XWB long-range widebody airliner—the very first of its kind. Sleek and nearly all white except for the lettering along its flank and the swirling blue-on-blue Airbus logo on the tail, it carries the official designation MSN001. Last May, in a modest employees-only ceremony, the final assembly line workers formally handed the plane over to the Flight Test Department. Or, as du Ché sees it, “They handed it to me.”

As a flight engineer and head of the department, du Ché gets first pick of the test flights. Although he describes himself as risk-averse, he tends to choose those he calls the most “interesting,” which means at the edge of the plane’s capabilities, where if something goes wrong, it could destroy the plane. Since June, du Ché and his colleagues have flown at the A350’s maximum design speed; conducted aerodynamic stalls; and taken off so slowly that the tail dragged on the ground.

Each test flight is operated by a crew of two pilots and three flight engineers, who monitor the stream of data flowing from a multitude of sensors into a bank of computers installed in the middle of the cabin. Du Ché’s station is behind the co-pilot’s on the right side of the cockpit. On the seat is a parachute. If things should go terribly awry and the crew needs to evacuate, a bright-orange railing leads them from the cockpit door to a hatch in the floor above the forward baggage compartment. By pulling a lever, the crew can trigger a set of explosive charges that will blow a hole in the right side of the fuselage. They can then leap down a slide, through the hole, and into the air. That’s the idea, anyway. Says test pilot Frank Chapman: “If the plane is tumbling out of control, would you really be able to get out?” He shrugs.

Read the rest of the article, from the February 13, 2014 issue of Bloomberg Businessweek, here.

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Popular Mechanics: How Panic Doomed an Airliner

On the evening of May 31, 2009, 216 passengers and 12 crew members boarded an Air France Airbus 330 at Antonio Carlos Jobim International Airport in Rio de Janeiro, Brazil. The flight, Air France 447, departed at 7.29pm local time for a scheduled 11-hour flight to Paris. It never arrived. At 7 o’clock the next morning, when the aircraft failed to appear on the radar screens of air traffic controllers in Europe, Air France began to worry, and contacted civil aviation authorities. By 11am, they concluded that their worst fears had been confirmed. AF447 had gone missing somewhere over the vast emptiness of the South Atlantic.

How, in the age of satellite navigation and instantaneous global communication, could a state-of-the art airliner simply vanish? It was a mystery that lasted for two years. Not until earlier this year, when autonomous submersibles located the airliner’s black boxes under more than two miles of water, were the last pieces of the puzzle put together. What doomed the 228 men, women and children aboard Air France 447 was neither weather nor technological failure, but simple human error. Under pressure, human beings can lose their ability to think clearly and to properly execute their training—a well-known failing that has proven all too difficult to eliminate.

Over at Popular Mechanics I’ve got a long piece offering a detailed blow-by-blow account of how one of the co-pilots of the Air France jetliner managed, in the course of just five minutes, to take a perfectly operational airplane from an altitude of nearly seven miles down to impact with the ocean. Here, I’d like to offer a nutshell summary of what happened, and what our understanding implies for the future of air safety. Read the rest of this entry »

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