Medical emergency forces plane to land

A Virgin jet flying from Adelaide to Sydney is back in the air after a sick passenger forced it to land in Melbourne.

The patient was taken to Royal Melbourne hospital in a stable condition, an Ambulance Victoria spokesman said.

Flight 401 left Adelaide at 6am but made a sharp southward turn about half way through the two-and-a-half-hour flight to Sydney, flight radars show.

The plane has since resumed its journey.