'Ocean of Debris' Found at Air France 447 Crash Site

An "ocean of debris" now surrounds divers recovering wreckage and bodies from Air France flight 447 in the Atlantic Ocean, and searchers today recovered the stabilizer from the plane's tail, according to the Brazilian Navy.

It's still unclear if the jet broke up in the air, or on impact. Former crash investigator Gregory Feith says they may be able to tell from the tail.

"If it's on the backside or the furthest up the debris chain, then there's a high probability that could have been one of the first components that came off the airplane," said Feith.

Investigators are looking into whether faulty speed sensors played a role. Airbus had recommended changing the sensors because of reliability issues, and Air France had noticed sensors icing up on some flights. Faulty speed readings can cause the jet to fly dangerously slow or fast.

VIDEO: Search Intensifies for Black Boxes Play

Much of the focus remains on those speed sensors because Air France said it was in the process of replacing them after seeing them freeze up and malfunction on other flights. The sensors had not yet been changed on flight 447.

Delta and USAirways, two airlines that operate Airbus jets, told ABC News today that they are replacing their speed sensors as a precaution.

Brazilian military authorities say boats searching the Atlantic Ocean have now recovered 24 bodies of passengers on an Air France flight that crashed eight days ago.

Five vessels are surrounded by airplane seats, fuselage, wire, television monitors, oxygen masks and personal belongings littered in an area more than 8,000 feet deep.

VIDEO: Recovered human remains and debris might provide clues to what went wrong.Play

The first of the bodies and debris pulled from the Atlantic Ocean this weekend should arrive back on shore today, where investigators will begin to get a better picture of what happened on Air France flight 447.

The evidence will be flown to the Brazilian island of Fernando de Noronha, some 400 miles off the country's coast. A little more than a week after the flight crashed with 228 people onboard en route from Rio de Janeiro to Paris, the hunt for clues is picking up pace.

Watch "World News with Charles Gibson" Tonight at 6:30 p.m. ET for the full report.

Air France 447: What Comes Next

Searchers are scouring an area 45 miles from where plane last sent a burst of messages. They'll look for more evidence from the plane crash, including additional bodies and pieces of the plane. In the grim recovery effort, human remains will provide clues about what may have gone wrong.

Frank Ciaccio, who supervised wreckage recovery for Egypt Air and other underwater accidents while working for the National Transportation Safety Board, said full forensic examinations are "not going to solve all the answers," but can still provide crucial information.

"Identifying them is going to be the No. 1 priority," said Ciaccio, forensics specialist and vice president of commercial services for Kenyon International Disaster Management Services. "No. 2 priority is going to be to document any injuries the body sustains so that they can add to the investigation, and help with putting a final picture together."

"It's not going to solve why this plane went down, but it'll give something back to the family members that do find their loved ones right now, and it'll give some hope to the other ones that hopefully they will be able to recover more of their loved ones," he added.

In his weekly radio program today, Brazil's president Luiz InĂ¡cio Lula da Silva said, "We will do whatever is within our reach, together with the Air Force and the Navy, to find everything we possibly can. And, above all, the bodies, because in this moment of grief, even though that will not solve the problem, it will be immensely comforting to the families to know that they are burying their loved ones."

Air France 447: Black Box Signals Will Last Another Three Weeks

The hunt for the plane's black boxes also begins in earnest this week.

Today, the U.S. Navy sends a team and two underwater, high-tech listening devices used in military crashes. The devices are towed behind a boat to listen for the "pinging" signal emitted from the plane's cockpit voice recorder and flight data recorders. They can detect the black boxes at depths of 20,000 feet and have been used in military accidents.

A French nuclear submarine is expected to arrive Wednesday to look for the black boxes. Those recorders could also tell investigators whether the pilots tried to turn back toward land. Investigators believe may have been the case, based on the location of the wreckage and bodies.

"The black boxes are really going to give a lot of information, a good 90 percent of the information," Ciaccio said. "These are all pieces of the puzzle. It would be like an incomplete puzzle with the black boxes not being recovered."

The boxes' locator signals may last just 22 more days.

Bodies and Clues: What Happened Over the Weekend

A total of 16 bodies recovered so far -- two Saturday and 14 Sunday -- give searchers a clearer idea of where plane went down. So do hundreds of personal items, including a piece of luggage and a boarding pass for the flight, as well as pieces of the plane found over the weekend.

Also this weekend, French investigators revealed that the plane sent out 24 electronic messages in four minutes detailing problems with electrical systems, pressurization and speed sensors.

"It does appear this air data system was involved in some way," said John Hansman, professor of aeronautics at the Massachusetts Institute of Technology. "They have to figure out why it went bad."

But experts caution about jumping to conclusions. The tragic accident was likely not caused by just one single failure, but rather a series of mishaps that brought the plane down.

"Airplanes are designed with sufficient redundancy that a single failure shouldn't cause an accident," Hansman said.

ABC News' Zoe Magee, Ammu Kannampilly, Renata Araujo, Sonia Gallego, Joe Goldman, Christel Kucharz, Luis Martinez, Phoebe Natanson, Fabiola Antezana, Gabriel O'Rorke, Samira Parkinson-Smith, Kirit Radia and Christophe Schpoliansky, Reuters and The Associated Press contributed to this report.