Wednesday, June 10, 2009

The Passenger Manifest

While recovery teams pull bodies and wreckage from the South Atlantic, French authorities are investigating a potential terrorist link to the crash of Air France Flight 447.

According to Sky News, French security officials have determined that two of the jet's 228 passengers had names linked to Islamic terrorism, and appeared on a list of individuals considered "a threat to the French Republic."

Agents from the DGSE (the French intelligence agency that performs functions similar to the CIA and DIA) made the connection while reviewing the passenger manifest for Flight 447, which departed from Rio de Janiero on 31 May. The Airbus A330 went down in violent weather off Brazil's northwest coast, about six hours into the flight to Paris.

An intelligence source told the paper L'Express that the link between passenger list and known terrorists was "highly significant," though the evidence is not conclusive. French authorities are now working to determine birth dates and family connections for the two passengers, attempting to determine if they are, indeed, the same individuals who appear on the terrorism list.

At this point, with the airliner's "black boxes" sitting on the bottom of the Atlantic, the exact cause of the crash remains a mystery. Weather was certainly a factor, although other jets negotiated the same conditions. Additionally, meteorological data suggests that the turbulence encountered by Air France 447 may not have been as bad as first thought.

Other theories center on the plane's computers and its fly-by-wire control system. Automated messages from the airliner indicate severe systems degradation and failures in the final minutes of its flight. But even that theory is a bit suspect; fly-by-wire technology (first used in military aircraft like the F-16) is a triple-redundant system. A complete failure of the flight control computers--and the surfaces they control--is a virtual impossibility, at least that's what the engineers say.

However, aircraft have a way of proving that the impossible sometimes happen. Twenty years ago this summer, United Airlines Flight 232 crashed while attempting an emergency landing in Sioux City, Iowa. The DC-10 lost all hydraulics after the failure of the plane's #2 engine, mounted on the tail. Shrapnel from the disintegrating engine punctured the jet's three hydraulic systems, leaving the pilots with only thrust from the two remaining engines to control the aircraft.

Almost everyone has seen the final moments of Flight 232. Just a few feet above the runway, the jetliner's right wing dipped and touched the ground, sending the DC-10 into a fiery cartwheel. One hundred and eleven people died, but miraculously, 185 passengers and crew survived, largely because of the skill of the cockpit crew, led by Captain Al Haynes.

The conditions that brought down United Flight 232 represented a "statistical impossibility" (according to safety experts), but they happened nonetheless. Similarly, the advanced flight management and control systems on that Airbus A330 aren't supposed to fail en mass, but that's one of the theories that investigators are pursuing.

Of course, the real question is whether the crash of Air France 447 had a little human assistance, in the form of those two passengers with names that turned up on that terrorist watch list. At this point, terrorism can't be ruled out, and it will be interesting to see what the DGSE turns up as they dig into the background of those passengers.


ADDENDUM: Whatever the cause, air safety experts will almost certainly learn from the Air France disaster, and those lessons can (hopefully) save lives in the future. The techniques used by Al Haynes on United 232 have been widely studied, and the airline Captain (now retired) still shares his expertise with pilots and other aviation groups.

Fourteen years after the Sioux City disaster, a DHL crew, flying out of Baghdad, faced similar circumstances after their cargo jet (an Airbus A300) was struck by a surface-to-air missile. The crew managed to return to Baghdad and get their plane on the ground, executing the only "safe" landing in commercial aviation history with a complete hydraulic failure. Incidentally, the Captain of that Airbus learned how to use differential thrust control techniques in a seminar he attended. The instructor for that course was Al Haynes.

UPDATE: The U.K. Telegraph reports that the two passengers whose names matched those on a terror watchlist have been ruled out as a cause of the disaster. French security officials say the dead passengers "only shared the same name" with known Islamic radicals. The Telegraph reports that the investigation is now centering on faulty airspeed indicators, which began sending "incoherent" readings to the aircraft's crew and control system, about four hours into the flight. The false readings could prompt the pilot's to fly the aircraft faster than the Airbus could withstand, or too fast for the stormy weather conditions.

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