Two hours later, Malaysian Airlines declared the plane had been lost.
Somewhere over the South Chinese Sea, just after 1am in the morning, the plane and its 239 passengers vanished. Search parties from Malaysia, China and Vietnam have still not located the plane.
Safest plane in the world
It's a six-hour flight, several Malaysia planes flew the route every week, and both Malaysia Airlines and the plane manufacturer Boeing have impeccable safety records.
Boeing's 770 range are rated as the safest plane in the world. Boeing 770 planes have flown more than 5.5million flights, and to date there had never been any crash fatalities.
The carrier - Malaysia Airlines - has one of the best safety records in Asia. Though its fleet of Boeing 770s were slightly older than average, it's an airline with a near top safety rating.
There are no clear answers here.
Communication mystery
But it's the communication failure that is particularly mysterious. The aircraft was comfortably cruising – at a stage of the flight when the pilot would have had plenty of time to report any mechanical problems to Air Traffic Control. But no distress calls were received.
And then, it's not just the lack of active communication, the plane should automatically update Air Traffic via an inbuilt tracker known as a transponder device. The transponder continually responds to requests for location - but why it stopped working is unknown
Since the start of the 1990s, there have been plane crashes but very few planes have "disappeared" - fewer than five are recorded here - and they tend to be small craft flying over particularly remote areas.
Transponders, built into the airplane's black box should continue working after crashes - and even underwater – though deep-water black box retrieval is hard and a race against the clock. They have a battery life of 30 days.
Black boxes on commercial aircraft also contain cockpit voice recorders which could provide some insight into what went wrong on that plane at 1am on Friday morning. Normally black boxes are fitted with underwater retrieval beacons – designed to make them easier to find in the event of a plane crashing into the sea.