What is the purpose of this helicopter fin antenna? I'm an airplane guy, but I've got a quick helicopter question. I've seen a few helicopters with what seems to be a fin shaped antenna on the middle of the fuselage just above the windshield. I've also seen them just below the cockpit. And sometimes there's two antennas, one above, and one below.


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Just curious what its purpose is?

The antenne balise de detresse is the one I'm curious about:
It can be quite difficult to see as the big fin in the first photo is a wire cutter and it seems that the arrow points to that.  

The second photo shows it a little more clearly.  It is a wire cutter.