​Whatever went wrong in the air off Western Australia on Sunday, it started quickly and violently, and it did not stop for far too long.

First, AirAsia X passengers told news outlets, there came a loud bang about 90 minutes into the flight to Kuala Lumpur. It woke some people up. Sophie Nicolas said it was an explosion on left wing, while Dave Parry remembered a strange smell wafting through the cabin.

Then the shaking. Endless shaking, up and down the jet. "Like you were sitting on top of a washing machine," a passenger told the ABC.

It lasted another 90 minutes, passengers reported - minutes full of tears, prayers and gallows humour as the rattling jet limped back towards the land.