FROM CNN

What happened? MH370 and other aviation mysteries


By Faith Karimi, CNN



Updated 0828 GMT (1528 HKT) August 1, 2015




























































































































Source: CNN
Plane debris headed to France for analysis 01:23


Story highlights
Decades ago, five Navy bombers disappeared on the Florida coast, never to be seen again
A company jet vanished in Angola and has not been heard from since



(CNN)The puzzling disappearance of a Malaysian jetliner last year is not the first time a plane has vanished without a trace.

As investigators analyze new debris from an Indian Ocean island to determine whether it's wreckage from the missing MH370, here are other cases of plane disappearances and disasters, some of which remain unsolved decades later.


2014: MALAYSIA AIRLINES FLIGHT 370
















Experts answer your MH370 questions 02:15
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The Boeing 777 passenger jet vanished in March last year -- about an hour into its flight from the Malaysian capital of Kuala Lumpur to Beijing. There was no distress call before it lost contact over the sea between Malaysia and Vietnam.

International search teams combed the Indian Ocean for months, but found no clues. This week, plane debris washed up on Reunion Island, and it's undergoing tests to determine whether it's linked to the missing jetliner. Aviation experts and government officials remain baffled over the mystery of the jet and the fate of the 239 people aboard.


2009: AIR FRANCE FLIGHT 447




Pieces of Air France Flight 447 were recovered from the Atlantic in June 2009.

The passenger jet, an Airbus A330, took off from Rio de Janeiro headed to Paris on May 31 of that year. A few hours later, as it crossed the Atlantic, it told control center its position.

That was the last contact with the plane. Its last known position -- two to four days by ship from the nearest ports -- complicated the searches.

It took almost two years before the bulk of the wreckage, the majority of bodies, and the voice and data recorders were recovered. All 228 people aboard died.

French authorities said ice crystals disrupted the system used to determine the plane's airspeed, causing the autopilot to disconnect. The plane plunged into the ocean.


2003: BOEING 727





Recent major plane crashes 27 photos
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The company jet vanished in the Angolan capital of Luanda.

It took off from the main international airport in the cityon May 25 of that year, headed for Burkina Faso. It departed with its lights off and a dysfunctional transponder.

There are conflicting reports on the number of people in the jet, but flight engineer Ben Charles Padilla is believed to be one of them. Some reports say he was alone, while others say three people were aboard.

The plane has not been heard from since. Its whereabouts are unknown to this day.


1999: EGYPTAIR FLIGHT 990




Journalists photograph possible EgyptAir Flight 990 debris in Nantucket, Massachusetts, in November 1999.

The passenger jet made a rapid descent, plunging almost 14,000 feet in 36 seconds.

The Boeing 767, en route to Cairo from New York City, crashed into the Atlantic Ocean off the Massachusetts coast in October of that year.

Though its debris was later found, speculation remains on the cause of the crash that killed all 217 people on board.

Theories included a possible suicide by the pilot or co-pilot, complete with tales of a chaotic struggle for controls in the cockpit. Egyptian authorities have said a mechanical failure was the cause.


1947: BRITISH STARDUST



The British aircraft vanished after takeoff from Buenos Aires, headed to Chile.

After searches for the plane named Stardust turned up nothing for more than 50 years, conspiracy theorists jumped into action. But theories of aliens, among others, were invalidated in 2000, when the wreckage of the plane was found buried deep in a glacier in the Argentine Andes.

The crash on August 2, 1947, killed 11 people, the BBC reported.

Stardust's final Morse code transmission was the word "STENDEC." The meaning of the word remains a mystery.


1945: FLIGHT 19 NAVY BOMBERS




Members of the Navy pose in front of one of the Flight 19 planes that disappeared in 1945.

Flight 19 refers to five Navy bombers that disappeared off the Florida coast on December 5 of that year.

A flight instructor flew one plane, and qualified pilots were in the others, according to the Naval History and Heritage Command.

Radio transmissions indicated that the instructor got lost when compasses malfunctioned. Radio contact was lost before the exact problem was determined, and no traces of the planes were ever found.

Adding to the mystery, a search aircraft sent to look for Flight 19 also disappeared. The patrol plane, which took off later that day, has not been seen or heard from since.

Flight 19 was reported in the area informally known as the Bermuda Triangle.


1942: BRITISH FIGHTER




A Royal Air Force P-40 Kittyhawk sits in the Egyptian Sahara. The plane crashed in 1942, and was found in 2012.

A stray Royal Air Force fighter crashed in the blistering sands of the Egyptian Sahara on June 28 of that year.

Its pilot was never heard from again, and the damaged P-40 Kittyhawk was presumed lost forever.

But in 2012, an oil company worker discovered it seven decades after the accident. Surprisingly, it was extraordinarily well-preserved, and most of its fuselage, wings, tail and cockpit instruments were intact.

Back then, experts say, planes flew with basic supplies,so its pilot's chances of survival were not good.


1937: AMELIA EARHART




In a photo taken in the 1930s, Amelia Earhart looks trough the cockpit window of her plane.

The disappearance of Amelia Earhart is possibly the most famous unsolved aircraft mystery.

The groundbreaking aviator was on her most ambitious flight, vying to become the first woman to fly around the world.

In 1937, she attempted the voyage in her twin-engine Lockheed Electra. With about 7,000 miles left to go, she made a challenging landing at Howland Island in the mid-Pacific.

Her radio transmissions became unclear, and the last thing she reported over her radio was, "We are running north and south," according to an online biography.

After spending $4 million and searching 250,000 square miles of ocean, the United States called off its search.

Many theories exist today, but her fate and that of navigator Fred Noonan remain unknown. This year, new footage emerged of her preparing for the doomed flight.


CNN's Mariano Castillo contributed to this report