I thought that too. Then you have to ponder what about the ETL signals. Also, our government stated that our satellites did not pick up any explosions at flight level.
It is a mystery... Somebody knows what happened..... we will find out in due course..
They also didn't see Crimea coming (or going may be a better way to put it.)
I could be wrong but I believe a signal is sent out if it crashes and they claim they never got that either.
I also consider that this is still a post 911 world outside of ObamaVille and other nations (especially Malaysia) are going to be much quicker at shooting down unidentified airplanes flying over their territory.