Story highlights Japan to join 8 other nations in search, ministry says

Plane's transponder had stopped, Malaysian Air Force official says

Missing flight was way off course, heading in wrong direction, official says

Experts unsure on what caused transponder to go off, what it means for plane

It was 1:30 a.m. when Malaysia Airlines Flight 370 lost all communications, including important transponder signals that send data on altitude, direction and speed. Still, it showed up on radar for about 1 hour, 10 minutes longer -- until it vanished, having apparently moved away from its intended destination, hundreds of miles off course.

Those details -- told to CNN by a senior Malaysian air force official, who declined to be named because he is not authorized to speak to the media -- seemingly shed more light on what happened to the aircraft that mysteriously went missing early Saturday.

But if these assertions are true -- and other reports, citing a different Malaysian official, cast doubt on them -- many big questions remain. Why were the communications lost? Why was the Boeing 777 going the direction it was? And where did it end up?

"Something happened to that airplane, that was obviously out of the norm, that caused it to depart from its normal flight path," said Mark Weiss, a former 777 pilot now with the Washington-based Spectrum Group consulting firm. "... It's difficult not to speculate."

Peter Goelz, former managing director of the National Transportation Safety Board, thinks all this information -- if correct -- ominously suggests that someone purposefully cut off the transponder and steered the plane from its intended destination.

"This kind of deviation in course is simply inexplicable," said Goelz.

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Other experts aren't convinced that there were bad actors -- be they hijackers or an ill-intentioned crew member. They say there could have been some sort of sudden catastrophic electronic failure or more that spurred the crew to try to turn around, with no luck.

"Perhaps there was a power problem," said veteran pilot Kit Darby, former president of Aviation Information Resources, adding that backup power systems would only last about an hour. "(It is) natural for the pilot, in my view, to return to where he knows the airports."

Still, while they have theories, even those who have piloted massive commercial airliners like this one admit that they can't conclude anything until the plane is found. For now, the massive multinational search has yielded no breakthrough -- which has only added to the heartache for the friends and family of the 239 passengers and crew on board.

The Malaysian air force official's revelations may provide more direction, though clarity and closure are still elusive.

"There are still as many possibilities out there, maybe more, now that we know about the transponders being off and the length of time that plane flew in the air without them," said CNN law enforcement analyst Tom Fuentes. "It still leaves mechanical, terrorism (and) other issues as much in the air as they were before."

Intentional or catastrophic mechanical failure?

According to the Malaysian air force official, the plane's transponder apparently stopped working at about the time flight controllers lost contact with it, near the coast of Vietnam.

The air force eventually and totally lost track of the plane over Pulau Perak, a tiny island in the Strait of Malacca -- many hundreds of miles from the usual flight path for aircraft traveling between Kuala Lumpur and Beijing, the official said.

If the data cited by the source is correct, the aircraft was flying away from Beijing and on the opposite side of the Malay Peninsula from its scheduled route.

Why would the transponder -- an electrical instrument in commercial airline cockpits that continuously transmits information such as altitude, location, direction and speed -- have gone off?

Goelz, the former NTSB managing director, and others point out the only reason for someone to intentionally turn off the transponder is to conceal the plane's location and direction. Someone with nefarious intentions of taking over an aircraft and steering it to where it wasn't supposed to be -- or perhaps planning on crashing it -- might do just that.

"You have to have a very deliberate process to turn the transponder off," he said. "... There might still be mechanical explanations on what was going on, but those mechanical explanations are narrowing quickly."

Anthony Roman, a trained pilot and consultant, said that a fast-moving fire might have moved through the cockpit and rendered everything, including the crew, effectively powerless to do much more than turn the plane around.

"Fires are insidious," Roman told CNN's Wolf Blitzer. "They can happen quickly and knock out multiple systems quickly."

Darby, for one, believes purely mechanical issues remain the most valid possibility now. His main point is: "Everything is electrical." In other words, if there's some sort of "catastrophic failure" for whatever reason, that could knock out systems like the transponder.

If that would happen, the plane could fly for some time without electricity but not indefinitely. Any attempts to steer it would be harder in the dark without functioning flight instruments said Darby, a retired United captain.

Whether the air force official's account is true, that possibility and others make the mystery more and more confounding.

Photos: The search for MH370 Photos: The search for MH370 Two years after Malaysia Airlines Flight 370 went missing, a relative of one of the passengers burns incense in Beijing on March 8, 2016. Flight 370 vanished on March 8, 2014, as it flew from Kuala Lumpur, Malaysia, to Beijing. There were 239 people on board. Hide Caption 1 of 43 Photos: The search for MH370 On July 29, police carry a piece of debris on Reunion Island, a French territory in the Indian Ocean. A week later, authorities confirmed that the debris was from the missing flight. Hide Caption 2 of 43 Photos: The search for MH370 Staff members with the Australian Transport Safety Bureau examine a piece of aircraft debris at their laboratory in Canberra, Australia, on July 20. The flap was found in June by residents on Pemba Island off the coast of Tanzania, and officials had said it was highly likely to have come from Flight 370. Experts at the Australian Transport Safety Bureau, which is heading up the search for the plane, confirmed that the part was indeed from the missing aircraft. Hide Caption 3 of 43 Photos: The search for MH370 In late February, American tourist Blaine Gibson found a piece of plane debris off Mozambique, a discovery that renewed hope of solving the mystery of the missing flight. The piece measured 35 inches by 22 inches. A U.S. official said it was likely the wreckage came from a Boeing 777, which MH370 was. Hide Caption 4 of 43 Photos: The search for MH370 Relatives of the flight's passengers console each other outside the Malaysia Airlines office in Subang, Malaysia, on February 12, 2015. Protesters had demanded that the airline withdraw the statement that all 239 people aboard the plane were dead. Hide Caption 5 of 43 Photos: The search for MH370 A police officer watches a couple cry outside the airline's office building in Beijing after officials refused to meet with them on June 11, 2014. The couple's son was on the plane. Hide Caption 6 of 43 Photos: The search for MH370 Members of the media scramble to speak with Azharuddin Abdul Rahman, director general of Malaysia's Civil Aviation Department, at a hotel in Kuala Lumpur, Malaysia, on May 27, 2014. Data from communications between satellites and the missing flight was released the day before, more than two months after relatives of passengers said they requested it be made public. Hide Caption 7 of 43 Photos: The search for MH370 Operators aboard the Australian ship Ocean Shield move Bluefin-21, the U.S. Navy's autonomous underwater vehicle, into position to search for the jet on April 14, 2014. Hide Caption 8 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks out of a window while searching for debris off the coast of western Australia on April 13, 2014. Hide Caption 9 of 43 Photos: The search for MH370 The HMS Echo, a vessel with the British Roya; Navy, moves through the waters of the southern Indian Ocean on April 12, 2014. Hide Caption 10 of 43 Photos: The search for MH370 A Royal Australian Air Force AP-3C Orion, on a mission to drop sonar buoys to assist in the search, flies past the Australian vessel Ocean Shield on April 9, 2014. Hide Caption 11 of 43 Photos: The search for MH370 A relative of a missing passenger cries at a vigil in Beijing on April 8, 2014. Hide Caption 12 of 43 Photos: The search for MH370 Australian Defense Force divers scan the water for debris in the southern Indian Ocean on April 7, 2014. Hide Caption 13 of 43 Photos: The search for MH370 A towed pinger locator is readied to be deployed off the deck of the Australian vessel Ocean Shield on April 7, 2014. Hide Caption 14 of 43 Photos: The search for MH370 A member of the Royal New Zealand Air Force looks at a flare in the Indian Ocean during search operations on April 4, 2014. Hide Caption 15 of 43 Photos: The search for MH370 On March 30, 2014, a woman in Kuala Lumpur prepares for an event in honor of those aboard Flight 370. Hide Caption 16 of 43 Photos: The search for MH370 The sole representative for the families of Flight 370 passengers leaves a conference at a Beijing hotel on March 28, 2014, after other relatives left en masse to protest the Malaysian government's response to their questions. Hide Caption 17 of 43 Photos: The search for MH370 A member of the Royal Australian Air Force is silhouetted against the southern Indian Ocean during the search for the missing jet on March 27, 2014. Hide Caption 18 of 43 Photos: The search for MH370 Flight Lt. Jayson Nichols looks at a map aboard a Royal Australian Air Force aircraft during a search on March 27, 2014. Hide Caption 19 of 43 Photos: The search for MH370 People in Kuala Lumpur light candles during a ceremony held for the missing flight's passengers on March 27, 2014. Hide Caption 20 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, delivers a statement about the flight on March 24, 2014. Razak's announcement came after the airline sent a text message to relatives saying it "deeply regrets that we have to assume beyond any reasonable doubt that MH 370 has been lost and that none of those onboard survived." Hide Caption 21 of 43 Photos: The search for MH370 Grieving relatives of missing passengers leave a hotel in Beijing on March 24, 2014. Hide Caption 22 of 43 Photos: The search for MH370 A passenger views a weather map in the departures terminal of Kuala Lumpur International Airport on March 22, 2014. Hide Caption 23 of 43 Photos: The search for MH370 A Chinese satellite captured this image, released on March 22, 2014, of a floating object in the Indian Ocean, according to China's State Administration of Science. It was a possible lead in the search for the missing plane. Surveillance planes were looking for two objects spotted by satellite imagery in remote, treacherous waters more than 1,400 miles from the west coast of Australia. Hide Caption 24 of 43 Photos: The search for MH370 Satellite imagery provided by the Australian Maritime Safety Authority on March 20, 2014, showed debris in the southern Indian Ocean that could have been from Flight 370. The announcement by Australian officials raised hopes of a breakthrough in the frustrating search. Hide Caption 25 of 43 Photos: The search for MH370 Another satellite shot provided by the Australian Maritime Safety Authority shows possible debris from the flight. Hide Caption 26 of 43 Photos: The search for MH370 A distraught relative of a missing passenger breaks down while talking to reporters at Kuala Lumpur International Airport on March 19, 2014. Hide Caption 27 of 43 Photos: The search for MH370 On March 18, 2014, a relative of a missing passenger tells reporters in Beijing about a hunger strike to protest authorities' handling of information about the missing jet. Hide Caption 28 of 43 Photos: The search for MH370 U.S. Navy crew members assist in search-and-rescue operations in the Indian Ocean on March 16, 2014. Hide Caption 29 of 43 Photos: The search for MH370 Members of the Chinese navy continue search operations on March 13, 2014. After starting in the sea between Malaysia and Vietnam, the plane's last confirmed location, search efforts expanded west into the Indian Ocean. Hide Caption 30 of 43 Photos: The search for MH370 A Vietnamese military official looks out an aircraft window during search operations March 13, 2014. Hide Caption 31 of 43 Photos: The search for MH370 Malaysian air force members look for debris near Kuala Lumpur on March 13, 2014. Hide Caption 32 of 43 Photos: The search for MH370 Relatives of missing passengers wait for the latest news at a hotel in Beijing on March 12, 2014. Hide Caption 33 of 43 Photos: The search for MH370 A member of the Vietnamese air force checks a map while searching for the missing plane on March 11, 2014. Hide Caption 34 of 43 Photos: The search for MH370 A Vietnamese air force plane found traces of oil that authorities had suspected to be from the missing Malaysia Airlines plane, the Vietnamese government online newspaper reported on March 8, 2014. However, a sample from the slick showed it was bunker oil, typically used to power large cargo ships, Malaysia's state news agency, Bernama, reported on March 10, 2014. Hide Caption 35 of 43 Photos: The search for MH370 A U.S. Navy Seahawk helicopter lands aboard the USS Pinckney to change crews on March 9, 2014, before returning to search for the missing plane in the Gulf of Thailand. Hide Caption 36 of 43 Photos: The search for MH370 Buddhist monks at Kuala Lumpur International Airport offer a special prayer for the missing passengers on March 9, 2014. Hide Caption 37 of 43 Photos: The search for MH370 Members of a Chinese emergency response team board a rescue vessel at the port of Sanya in China's Hainan province on March 9, 2014. Hide Caption 38 of 43 Photos: The search for MH370 The rescue vessel sets out from Sanya in the South China Sea on March 9, 2014. Hide Caption 39 of 43 Photos: The search for MH370 Malaysian Prime Minister Najib Razak, center, arrives to meet family members of missing passengers at the reception center at Kuala Lumpur International Airport on March 8, 2014. Hide Caption 40 of 43 Photos: The search for MH370 A relative of two missing passengers reacts at their home in Kuala Lumpur on March 8, 2014. Hide Caption 41 of 43 Photos: The search for MH370 Chinese police at the Beijing airport stand beside the arrival board showing delayed Flight 370 in red on March 8, 2014. Hide Caption 42 of 43 Photos: The search for MH370 Malaysia Airlines Group CEO Ahmad Juahari Yahya, front, speaks during a news conference at a hotel in Sepang on March 8, 2014. "We deeply regret that we have lost all contacts" with the jet, he said. Hide Caption 43 of 43

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"You couldn't make this story up," said Michael Goldfarb, a former official with the Federal Aviation Administration.

Terrorism a possibility

Authorities have said they're looking at all possibilities to explain what happened to the Malaysia Airlines aircraft.

Earlier Tuesday, the head of the international police organization Interpol said that his agency increasingly believed the incident was not related to terrorism.

"The more information we get, the more we're inclined to conclude that it was not a terrorist incident," Interpol Secretary General Ronald Noble said at a news conference in Lyon, France.

Yet -- speaking Tuesday about what he called a "very disturbing mystery" -- CIA Director John Brennan insisted terrorism remains a possibility.

"I don't know (what happened)," he said. "But I don't think people should, at this point, rule out any of these lines of inquiry."

The two passengers who have dominated headlines the last two days entered Malaysia using valid Iranian passports, Noble said. But they used stolen Austrian and Italian passports to board the missing Malaysian plane, he said.

Noble gave their names and ages as Pouri Nourmohammadi, 18, and Delavar Seyed Mohammad Reza, 29.

Malaysian police had earlier identified Nourmohammadi, using a slightly different name and age, and said they believed he was trying to migrate to Germany.

Inspector General Khalid Abu Bakar of the Royal Malaysian Police said it doesn't appear the younger Iranian posed a threat.

"We have been checking his background," Khalid said, noting "other police organizations" have been consulted. "And we believe that he is not likely to be a member of any terrorist group," Khalid said.

After he failed to arrive in Frankfurt, the final destination of his ticket, his mother contacted authorities, Khalid said. According to ticketing records, the ticket to Frankfurt was booked under the stolen Austrian passport.

Extensive search for plane

No one knows where these two men and the other 237 people on the plane ended up. Every lead that has raised hopes of tracing the commercial jet has so far petered out.

Over the past few days, search teams have been scouring tens of thousands of square miles of sea between the northeast coast of Malaysia and southwest Vietnam. They have also been searching off the west coast of the Malay Peninsula, in the Strait of Malacca, and north into the Andaman Sea.

The search also encompasses the land in between the two areas of sea.

But it could be days, weeks or even months before the searchers find anything that begins to explain what happened to the plane, which disappeared early Saturday en route to Beijing.

In the case of Air France Flight 447, which disappeared over the Atlantic in 2009, it took five days just to find the first floating wreckage.

And it was nearly two years before investigators found the bulk of the French plane's wreckage and the majority of the bodies of the 228 people on board, about 12,000 feet below the surface of the ocean.

The Gulf of Thailand, the area where the missing Malaysian plane was last detected, is much shallower, with a maximum depth of only 260 feet and an average depth of about 150 feet.

Still, they have to find it first. The newly disclosed revelation about the plane's direction doesn't help, as it means less certainty and more time for currents to move the wreckage around.

"Crucial time is passing," David Gallo, with the Woods Hole Oceanographic Institution, told CNN's Wolf Blitzer on Monday. "That search area -- that haystack -- is getting bigger and bigger and bigger."

Thailand, Singapore, Indonesia, Vietnam, Australia, the United States, China and Malaysia are all taking part in the search, White House spokesman Jay Carney said. Japan has also dispatched a team to the area, with Japanese military and coast guard crews likely to follow, its foreign ministry announced Wednesday.

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That helps takes all forms, such as many as 10 Chinese satellites monitoring the area to the helicopters ready-to-dispatch off of U.S. warships.

CNN aviation correspondent Richard Quest described the search as "extremely painstaking work," suggesting a grid would have been drawn over the ocean for teams to comb, bit by bit.

Quest said that the expanding search area shows how little idea rescue officials have of where the plane might be. But he's still confident they'll find it eventually.

"It's not hopeless, by any means. They will find it," he said. "They have to. They have to know what happened."

Until they do, patience is growing thin for friends and family members of those aboard Flight 370.

As a middle-aged man -- the father of one such passenger -- shouted Tuesday at an airline agent in Beijing: "Time is passing by."