You'd have a tough time convincing residents of Twin Falls County's West End that the recent late-night mystery noises aren't coming from the Air Force ... The eastern edge of the Idaho Training Range is only 40 miles from Castleford and Buhl, and a supersonic jet travels 40 miles in 3 minutes ...

So West Enders are accustomed to things that go bump - and go bump loudly - in the night ...

"Usually we hear the explosions when the air is humid and cold, thus transmitting sound easier," said Filer farmer Bill Bitzenburg ... "Many times in the summer you see flashes then hear nothing, because of the warm thin air" ...

In March 1997, a sonic boom was blamed for damaging the Castleford High School gym - $150,000 worth of damage ... The Air Force denied it was responsible and refused to pay compensation ...

But the incident transformed many Castleforders into amateur sonic boom experts, packing stopwatches so they could keep track of sonic bombs and correlate them with reported training sorties out of Mountain Home Air Force Base ...

They had good reasons: From 1995 until 2002, for example, Mountain Home was the home of B-1B bombers, which roar overhead at up to 115 decibels ...

Your lawnmower, by contrast, chugs along at less than 100 decibels ...