Experts continue to search for the plane, which fell off radar screens Saturday during a flight from Kuala Lumpur, Malaysia, to Beijing. Families of the 239 people on board have been warned to expect the worse and searchers, including groups from the U.S. military continue to look for clues to the plane's fate.
The disappearance of Flight 730 isn't the first aeronautics mystery to leave investigators searching for answers, often for years. Politico has detailed some of the biggest past mysteries involving plane crashes and disappearances. Here's what they found:
1 .The crash of Air France Flight 447 in 2009 seems eerily similar to the Malaysia flight. It disappeared over the Atlantic en route from Rio de Janeiro to Paris. As with the Malaysia flight, the Air France pilots issued no distress call and the fate of the 228 people on board remained a mystery for five days until search-and-rescue teams found a tail section in the water.
The plane went down in a deep section of the Atlantic Ocean and recovery of its black boxes took more two years. The crash was later blamed on ice crystals that blocked the plane's airspeed sensors, causing it to stall.
2. Eighteen years after exploding and crashing near East Moriches, NY, TWA Flight 800 remains controversial. The plane crashed July 17, 1996 after takeoff from John F. Kennedy International Airport, killing 230 people. Theories abounded the plane was brought down by a missile but the National Transportation Safety Board said the accident was probably caused by an explosion of flammable fuel/air vapors in a fuel tank.
Conspiracies surrounding TWA Flight 800 remain. As recently as last summer, a filmmaker said he had "solid proof" the plane was brought down by a missile.
3. EgyptAir Flight 990 was enroute from New York City to Cairo on Oct. 31, 1999 when it crashed into the Atlantic Ocean off the coast of Massachusetts. All 217 people on board were killed.
The NTSB said the relief first officer in the cockpit deliberately caused the crash, citing evidence such as the cockpit voice recordings that showed the captain and the first officer struggled for control of the plane.
The Egyptian government disputed those claims and said the crash was caused by a mechanical failure of the plane's elevator control system.
4. Flying Tiger Line Flight 739, a Lockheed L-1049 Super Constellation prop plane, was chartered by the U.S. military to take 93 Army men and 3 South Vietnamese from Travis Air Force Base, Calif. to Saigon, Vietnam. The plane disappeared over the western Pacific Ocean on March 16, 1962.
All 107 aboard were declared missing and presumed dead.
According to Politico, the airplane's disappearance prompted one of the largest air and sea searches in the history of the Pacific. Aircraft and surface ships from four branches of the military searched more than 200,000 square miles but no trace of wreckage or debris was ever recovered. It's believed the plane exploded in-flight but the exact cause is not known.
Potential theories pointed to sabotage, hijacking or even friendly fire.
5. The story of Amelia Earhart in 1937 continues to captivate the public. Earhart and her navigator, Fred Noonan, disappeared over the Pacific Ocean on July 3, 1937 as they attempted to circumnavigate the world. The U.S. Coast Guard reported losing contact with the plane near a small strip of land called Howland Island between Hawaii and Australia.
An immediate search began but was called off after two weeks. Earhart was declared dead in 1939. Recent artifacts found on an island south of Howland Island indicated she may have ditched the plane and survived for a time, but no concrete proof exists.
6.Glenn Miller, a famed 1940s bandleader, was a major in the Army Air Force in 1944. On Dec. 15, he boarded an RAF Norseman C-64 in England on his way to Paris. The plane never reached its destination and is believed to have crashed over the English Channel in foggy weather. No trace of the plane or passengers has ever been found.
Again, conspiracy theories about Miller's disappearance abound. They range from an errant Royal Air Force bomb to Miller being accidentally shot by a Paris policeman with the killing covered up by the U.S. military.
7. No look at aeronautic mysteries would be complete without
the Bermuda Triangle. Perhaps the most famous story is that of Flight 19. On
Dec. 5, 1945, five TBM Avengers took off from Fort Lauderdale, Fla. on what was
supposed to be a two-hour training flight.
About 90 minutes into the flight, Fort Lauderdale received confusing transmissions from the Flight 19 pilots, indicating they thought they were over the Florida Keys. Transmissions from the flight ended shortly afterwards and no wreckage of Flight 19 has been found. The disappearance helped fuel the mystery surrounding the Bermuda Triangle, which has been the site of both plane and ship disappearances.