malaysia family
A relative of a passenger on board Malaysia Airlines MH370 cries during a protest in front of the Malaysian embassy in BeijingReuters

Missing Malaysia Airlines flight MH370's black box may not be enough to solve the mystery of the aircraft's abrupt disappearance, experts have claimed.

The flight data and cockpit voice recorders might not explain how and why the plane diverted an hour into the flight, and was directed to the southern reaches of the Indian Ocean.

According to US aviation consultancy firm Leeham Co, the data recorder contains information such as the aircraft's path and the flight's duration, but the cockpit voice recorder retains only the last two hours of conversations before the plane's demise.

Information regarding the reasons why the plane was diverted could therefore be lost.

"Clearly, it won't reveal anything that happened over the Gulf of Thailand -- this will have been overwritten by the end of MH370," Leeham said.

The firm then added that it also remains to be seen whether the cockpit recorder will contain anything pertinent about the plane's final two hours.

The view is shared by British aviation expert Chris Yates, who believes that even if the black box is found "it seems unlikely that we will get that answer" of why the plane ended up thousands of kilometres off course.

"We still have no idea as to the mental state of the pilot and co-pilot, we have no idea if somebody managed to get into the cockpit to seize the aircraft, and we've certainly had no admissions of responsibility since this whole episode started," he told BBC television.

"It is a mystery like no other."

While the search for the missing aircraft continues, debris has been found in the Australian Ocean, but no physical evidence of the aircraft has yet been retrieved.

Malaysian Airlines management said in a public statement they assume "beyond any reasonable doubt" that the missing flight "has been lost and that none of those on board survived".

The announcement was received with grief and dismay by the relatives of the passengers, prompting China to double-check the data to verify Malaysian authorities' assumption.