A year on, what's the latest in the hunt for Flight 370?

Q: Do the chances of finding the plane in the priority zone become less likely as the search drags on?

A: No, Dolan says, because they haven't been able to pinpoint any areas within the search zone where the plane would have had a higher probability of crashing. Officials could only narrow down the most likely crash site to the 60,000-square-kilometer (23,000-square-mile) priority zone. "Some people think there's a hot spot in there that should be a starting point, but it's pretty much equal priority across that area," Dolan says. "So it's no great surprise that having covered 40 percent, we haven't located it yet. It might be down to the last 1 percent before we do."

Q: What happens if they find the plane?

A: Australia recently asked for expressions of interest from companies with equipment capable of retrieving wreckage from the seabed, which is an average of 4,000 meters (13,000 feet) deep. But bringing it to the surface would be complex.

Search officials would first need permission from the governments involved _ namely Malaysia and Australia _ to retrieve the wreckage. Then they would have to figure out the best way to do so.

Officials would need to map the area, photograph the debris and get specialized vessels, crews and equipment to the remote search site. All told, Dolan estimates that if the plane is found on the seabed, it would be at least a month before the recovery process even begins.

Q: If the plane is found underwater, what kind of condition would it be in after a year?

A: Although pressure on a plane deep in the ocean would be extreme, currents at those depths would be relatively mild _ meaning there's no real concern about debris continuing to scatter once it hit the seabed. After studying the condition of the wreckage from Air France Flight 447, which was found at a similar depth two years after crashing into the Atlantic Ocean, officials think any underwater debris from the Malaysian plane would be relatively well-preserved.

"It's not going to be a pristine aircraft," Dolan says. "But for our purposes, we expect that the aircraft remains will be in satisfactory condition."