The disappearance of Malaysia Airlines flight MH370 has captured the attention of the world, and investigators and aviation experts are yet to provide an explanation.
While some people are asking the question how a Boeing 777 with 239 people on board can simply 'disappear', it's not the first aviation mystery of its kind.
Today we look at 10 flights that baffled the world - some which have been solved and some not.
1. Amelia Earhart, 1937
American aviation pioneer Amelia Earhart was a popular author and feminist whose death is still shrouded in mystery. The first female to fly solo across the Atlantic Ocean, she decided to attempt to circumnavigate the globe in 1937.
On her second attempt, she was approaching Howland Island in her twin-engine monoplane Electra on July 2, when she radioed in that she was unsure of her location and that gas levels were low. She lost radio contact shortly after.
Search efforts started an hour after Earhart's last recorded message and despite a wide-spread search - including assistance from the US Navy - no trace of Earhart or her plane were ever found.
She was declared legally dead on January 5, 1939.
2. Flight 19 - 1945
Sparking the mystery of the Bermuda Triangle, five torpedo bombers left Fort Lauderdale, Florida, to undertake a routine training exercise. Test bombing began but pilots soon started reporting that they were disorientated and unable to recognise landmarks. Unable to recover their bearings, the five planes disappeared, killing 14 men.
PBM Mariner, a seaplane with 13 crew sent in to search for the planes also disappeared the same day.
Initially the Navy wrote a 500-page investigation which placed primary responsibility on flight leader, Navy Lieutenant Charles Carroll Taylor, but this was subsequently changed to 'cause unknown'.
3. UC-64 Norseman - 1944
Glenn Miller was a popular musician and composer whose most notable songs include Chattanooga Choo Choo and Little Brown. He was travelling throughout Europe to perform for the troops and on December 15, he was to fly from the United Kingdom to Paris. His flight disappeared while flying over the English Channel.
No trace of the plane, Miller or other members of the flight have ever been found.
4. Star Dust - 1947
Carrying six passengers and five crew, BSAA Star Dust left Buenos Aires on August 2, 1947 to fly to Santiago, Chile. The air crew were top-notch ex-Royal Air Force. When Star Dust didn't arrive at its location at 5.45pm, search teams were sent out to find the plane.
Despite a massive five-day search by pilots from Chile, Argentina and the BSSA, no trace was found of the aircraft or the people on board.
The Star Dust flight remained a mystery for more than 50 years, when two Argentinian rock climbers discovered wreckage from the plane in the Andes in 1998. Further investigations also found human remains.
A 2000 Argentine Air Force investigation says that the crash resulted from a heavy snowstorm and cloudy weather which meant the crew were 'unable to correct their positioning.'
5. Star Tiger - 1948 and Star Ariel - 1949
Compounding the Bermuda Triangle legend were two flights that disappeared a few years after the Flight 19 mission. The BSAA Star Tiger was flying from Santa Maria to Bermuda on 30 January 1948. Control stations were unable to contact the plane and, although there was no distress message, receiving stations were still able to listen to the Star Tiger's frequency. A five-day rescue effort failed to find the plane, nor its 31 passengers and crew.
A year later, another BSSA passenger aircraft, the Star Ariel, was travelling between Bermuda and Kingston, Jamaica. Despite contact an hour into the flight by the Captain, messages stopped and a search was instigated. No trace of the plane or its 20 passengers and crew have ever been found.
6. Pan Am Flight 7 - 1957
The Clipper Romance of the Skies, a Boeing 377, left San Francisco for Honolulu with 44 people on board. Half way into the flight, there was a routine radio check-in but they were never heard from again. It was later reported that the search was the largest deployed in peace time since the search for Amelia Earhart.
A week later, a Navy carrier spotted wreckage and bodies and recovery efforts began.
While toxicology reports indicated a higher level of carbon monoxide, the cause of the crash has never been determined.
7. Flying Tiger Line Flight 739 - 1962
With more than 107 people on board, Flight 739 was transporting military personnel from Guam to the Philippines when it disappeared. No distress call was ever issued and a wide-scale search that involved over 1,300 people from the Navy, Air Force, Coast Guard and Marines found no trace of Flight 739.
Two other Flying Tiger Line planes crashed on the same day as Flight 739, sparking sabotage theories. Despite this, no cause has ever been found.
8. Uruguayan Air Force Flight 571 - 1972
Chartered Flight 571 was travelling from Uruguay to Chile, including an overnight stop in Argentina. There were 45 people on board, including members of the Uruguayan rugby team. On Friday 13 October, the plane crashed, killing 12 with five more people dying the following day, and one a few days after that. Eight more died 16 days later when they were covered by an avalanche as they slept.
Believing all the passengers dead, search efforts stopped after eight days. More than two months later Nando Parrado and Roberto Canessa managed to trek their way across the mountains and alert rescuers to the other 14 passengers who were still alive.
It is believed that poor visibility and pilot error were the cause of the crash.
9. TWA Flight 800 -1996
The Boeing 747 left JFK airport on July 17 with 230 people on board, heading to Paris. 12 minutes after takeoff, the plane exploded, killing all crew and passengers.
With speculation of a terrorist attack or government cover-up both the National Transportation Safety Board and the FBI investigated the crash. After four years it was determined that the probable cause of the crash was an explosion of flammable fuel or air in a fuel tank.
10. Air France 447 - 2009
On June 1, the Airbus A330-203 airliner left Brazil to travel to Paris carrying 228 passengers and crew. When the flight had failed to check in with air traffic control and there were several failed attempts to contact Flight 447, an aerial search began. It took five days for teams to find the wreckage.
It took three years for investigators to conclude that a range of factors, including technical failures and pilot inexperience.