The international investigation team set up by Malaysia released its interim report yesterday, the first anniversary of the disappearance. It contained no new clues on what caused the plane to vanish with 239 passengers and crew aboard.
But analysts and next of kin raised questions over some findings, including the revelation that the beacon battery on the flight data recorder had expired more than a year before the flight.
She called the report part of a continuing Malaysian "cover-up".
The battery discovery "raises issues over the integrity of maintenance" at the carrier, said Greg Waldron, Asia managing editor for Flightglobal magazine.
Also Read
"Did that play a role in the inability to find the plane? We really don't know if that was a factor," he said.
The plane is believed to have crashed in the remote southern Indian Ocean, but nothing has been found despite an expensive and difficult search effort led by Australia.
But the airline said the battery on the separate cockpit voice recorder - good for 30 days once activated - was up-to-date and would have transmitted a signal once it hit water.
It added that the carrier had "taken significant steps to improve safety" since MH370.
The plane vanished at night over the South China Sea after turning away from its north-bound route from Kuala Lumpur to Beijing.
The government and state-controlled airline came under fire in the crisis's chaotic early days for a series of confusing and contradictory statements.
Malaysia's military did not act, infuriating relatives over the missed opportunity to follow the plane.
But the investigative report, citing radar records, said a blip "consistent" with the military radar data actually did appear on civilian screens several times for about 30 minutes after the plane diverted and doubled back over Malaysia.