... the P-8A, a heavily modified version of Chicago-based Boeing’s 737 commercial airliner, is joining two Royal Australian Air Force AP-3C Orion surveillance aircraft to hunt for Flight 370 in an area of the open ocean.
The P-8A is the Navy’s newest surveillance plane. The P-3C Orion is a four-engine turboprop built by Lockheed Martin and has been in service in the Navy since the 1960s.
Flying at 288 to 311 miles per hour, the Poseidon can search for as long as nine hours, “depending on the transit distance some flights may only have two to three hours of search time” Mize said.
Surveillance planes use different search patterns depending on the object being tracked and other details about the target, said Boston, now based in Troy, Va.
“If the exact last position is known, the Navy will typically assign an expanding circle” from that starting point, known as the datum, which expands at the rate a submarine or target is known to be moving, he said.
Depending on the mission, commanders have to make a series of calculations on how high to fly, the length of a single track and the spacing between tracks to mount an effective search, Boston said.
If the crew detects anything or is given more precise search locations, they could drop sonobuoys — launched from the plane’s belly that act like underwater microphones to listen for any “pings” from the missing plane’s black boxes, Burgess said. The pingers are supposed to emit signals for 30 days after becoming immersed in water.
While the black boxes are designed to withstand depths of 20,000 feet and may work in even deeper water, the range of the pings is a mile, according to manuals from Honeywell, the maker of the equipment. That may make the signals difficult to pick up even if an underwater microphone is over the correct location.
The emergency-locator transmitters on a 777 are designed for land and don’t work underwater, nor do the satellite transmissions used to triangulate the likely last-known location.
“I just don’t have a lot of hope for success in this effort because of the distance the plane could have gone,” Burgess said.
“At some point, you have to decide whether it’s worth it or not anymore,” he said. “Your hope of finding something goes down as time goes on. I would call it off in three or four days” if nothing is found.
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