Those news stories about the shoot down of a Jordanian F-16 at low altitudes with a shoulder fired are irrelevant in this case, because such a should fired weapon has no capability whatsoever to reach the 31,000 altitude of the airliner. The F-16 was shot down while at less than 12,000 foot altitude. Furthermore, the wreckage of the Airbus does not have any shrapnel damage from a missile warhead, so we know it was not shot down by a missile.