Originally Posted by
LowObservable
Having been diagnosed with a life-threatening allergy to pies in my youth, I have never flown MPA.
But if counter-detection is important, then what's the spec? What are the standards? Are there any? Because I would be willing to bet that a little C295 with modern six-blade props has one heck of a lot different signature from the P-3 with those four-paddle-blade things. And the Treasury is not interested in anecdotes.
Given that acoustic detection of submarines often focussed on the sounds created by the prop, isn't it fair that they can detect aircraft the same way. Any prop (4 blade or 6) emits detectable discrete frequencies, jets make more of a white noise blend which is less easy to identify.