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With jet possibly miles from last known position, search area expands

An officer in a helicopter joined the search Monday for Malaysia Airlines flight MH370.

ATHIT PERAWONGMETHA/Reuters

An officer in a helicopter joined the search Monday for Malaysia Airlines flight MH370.

WASHINGTON — As the hours drag by with no trace of the Malaysia Airlines flight that disappeared early Saturday, the world is getting a reminder that if something goes wrong on a jet five miles up, traveling at 10 miles a minute, it can cover a lot of distance before it comes down to earth.

There is only speculation about what happened to the missing flight, which was headed over the Gulf of Thailand to Beijing from Kuala Lumpur, the Malaysian capital.

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But Arnie Reiner, a retired captain with US Airways and former chief accident investigator at Pan Am, noted, “If they somehow got turned around or went off course when the thing was going down, it could be 90 or 100 miles away from where the flight data disappeared.”

It is not yet known whether the Malaysian plane deviated from its planned flight path, or how long the pilots could still fly the aircraft after the last reported contact.

Assuming that the plane remained in powered flight or a controlled glide, the potential search area would have to be wide and long, covering thousands of square miles. After more than two days of fruitless search, Malaysian officials expanded the search area Monday.

It is not yet known whether the Malaysian plane deviated from its planned flight path.

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The rule of thumb for a crew planning a normal descent to an airport is to allow three miles of distance for every thousand feet of altitude. So a jetliner at 30,000 feet that cut its engines to idle would fly another 90 miles or so before reaching a runway near sea level.

More than 1,000 people, with at least 34 planes and 40 ships, are searching a radius of 100 nautical miles around the plane’s last known location.

Not all planes that go down at sea prove difficult to locate.

When Egyptair Flight 990 crashed 60 miles from Nantucket, Mass., on Oct. 31, 1999, investigators quickly concluded that the aircraft, a Boeing 767, had followed a straight track, and Navy searchers picked up signals from the “pingers” on the aircraft’s black box data recorders the next day.

But extended searches are sometimes needed. When Air France Flight 447 vanished over the Atlantic in June 2009, it took five days to find any wreckage, and almost two years to find the black boxes.

Similarly, the cockpit data recorder from a South African Airways Boeing 747 that went down in November 1987 was not located until January 1989. It revealed that the plane crashed because of a fire onboard, not because of an act of terrorism, so no further search was conducted for the flight data recorder, the other black box.

Another assumption for pilots may shed light on why no distress signal was heard from the Malaysia Airlines flight. Pilots have a mantra for setting priorities in an emergency: Aviate, navigate, communicate.

The first priority is to fly the airplane. Telling air traffic controllers on the ground what is going on comes third, since doing so is unlikely to instantly yield any help with the crisis in the cockpit, whatever it is.

Although officials have not ruled out terrorism in the Malaysia Airlines case, no evidence of foul play has come to light. No group has claimed responsibility for downing the jet either, though as Reiner noted concerning the 747 that exploded over Lockerbie, Scotland, in 1988, “when Khadafy’s guys blew up Pan Am 103, they weren’t talking about it.”

The mystery will probably not be solved until the wreckage, and especially the black boxes, are recovered.

The wreckage alone could yield important clues, including whether the plane broke up in flight, suffered an explosion or had a mechanical failure. In most crashes, definitive findings on these questions take months or even years to establish.

A team of American experts from the National Transportation Safety Board, the Federal Aviation Administration, and Boeing has been sent to the area and is waiting for something concrete to go on.

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