Nobody has said it in so many words, but those searching the Indian Ocean for Flight MH370 would appear to be driven by the principle that failure is not an option.
The public voice of the search, retired Australian air chief marshal Angus Houston, speaks in carefully scripted and measured tones. He has explained that four separate acquisitions of ping signals made by the Australian vessel Ocean Shield have resulted in “better defining a reduced and much more manageable search area on the ocean floor.”
The pings are, he said, consistent with those transmitted by the airplane’s flight data recorder and cockpit voice recorder. In other words, there could be no other probable source for the signals—and their declining duration and strength would reflect that the batteries powering the transmissions are nearing the end of their lives.
The armada of ships, both military and civilian, and the fleet of search airplanes are now all dependent on those aboard the Ocean Shield being able to make accurate calculations of the Boeing 777’s probable point of impact. The pinging detector towed by the Ocean Shield is really the last best hope of pulling this off.
The robot’s “pilots” aboard ship need a well-defined target area, which is why the accuracy of the calculations now being made from the pinger signals is so crucial.
Air marshal Houston was careful to make it clear that, however encouraging, the ping detections were not in itself enough. “We need to visually identify wreckage before we can confirm that this is the final resting place of Flight MH370.”
That can happen only with the deployment of a remote-controlled deep diving vessel supplied by the U.S. Navy that is standing by aboard the Ocean Shield. This device, looking rather like a bloated torpedo, is equipped with lights and cameras that scan the seabed for debris. But it cannot be deployed on a random search—before it dives, the robot’s “pilots” aboard ship need a well-defined target area, which is why the accuracy of the calculations now being made from the pinger signals is so crucial.
The Indian Ocean seabed in the area that is now the focus of the search is around 16,000 feet deep, and the Australians have pointed out that there is a thick layer of silt at that depth, which could be muffling signals from the black box.
There is another decisive factor in the chances of locating a crash site: the extent of the debris field. This is critically influenced by how the airplane hit the water. The most obvious guide would appear to be Air France Flight 447 that disappeared in the south Atlantic in 2009. In that case the Airbus 330 hit the water in an attitude very similar to a final approach at an airfield—its wings were level and its nose pointed slightly up, and it was at a forward speed of a little more than 120 mph. The rear of the fuselage hit the water first, creating a severe upward force that was enough to compress the cargo hold and the cabin floor above it. The airplane broke up into several large sections and hundreds of smaller pieces. Two years later, when a deep-diving robot finally located the wreckage, the debris field was relatively compact—660 by 1,970 feet.
Nobody knows how Flight MH370’s Boeing 777 hit the water. There are conflicting theories—one body of expert opinion believes that the airplane would, once its engines stopped, have glided in a relatively stable attitude like the Airbus and, therefore, broken up on impact much as that airplane did. Another view (shared by me) is that the Boeing would have first lost power in one engine as its fuel ran low and, given continued power from the other engine would have been unbalanced, banked steeply, and dived into the ocean.
Some idea of how violent impact with the ocean can be is provided by the example of Swissair Flight 111, an McDonnell Douglass MD-11 that crashed into the Atlantic off of the coast of Nova Scotia in 1998. A fire in the cockpit had raged out of control in a matter of minutes and the pilots lost control. The airplane hit the water at 345 mph and broke into millions of pieces. Fortunately, that occurred in relatively shallow water easily accessible from the coast; even then the investigation took four years to complete.