Almost 300 people died when Malaysia Airlines flight MH17 was shot out of the sky by a missile over Ukraine yesterday afternoon local time, likely by pro-Russian separatists.

As there were at least 27 Australians on board, some of our readers will no doubt be affected by this tragedy, which, as Cathy Alexander and Paul Millar report today, comes second only to the Bali bombings in terms of Australian lives lost in a terrorist attack. It’s also our worst air disaster since 1960. And the number of Australians killed in the crash may rise over the coming days as authorities identify the victims.

Crikey’s resident aviation expert, Ben Sandilands, has been live-blogging the news as it comes to hand (with a short interruption when our site crashed earlier today — our apologies for that).

What was a civilian airliner doing flying over an active war zone where other planes have been shot down recently? It turns out MH17 wasn’t the only commercial plane in that airspace. As Sandilands reports today, two very lucky Singapore Airlines jets took a similar route. Did these airlines choose fuel economy over safety?

It’s been reported that many of the passengers on the flight were medical and scientific experts due to make a connection to Melbourne, where they were to attend the International AIDS Conference. We are saddened to hear these researchers were among the dead. Crikey’s thoughts go out to all the families, colleagues and friends affected by this disaster.