https://news.google.com/newspapers?nid=4pF9x-cDGsoC&dat=19960726&printsec=frontpage&hl=en Black Box Noise Suggests Bomb: The rate of mechanical failure dropped from 20 percent chance to 5 or 10 percent and US airports respond in kind in the article above:
Sorry it won't let me copy and paste anything from the now long defunct archives you'll have to see it yourself but it's well wroth reading especially the right hand of the 1st page about new security changes and passengers having to wait for an hour domestic flights and even longer international which they say international has been strict for more then 10 years:
there doesn't seem to be anything here