Just one small detail, it's purty likely there ain't pilots flyin those planes, there's mounting evidence to prove this in quite a few cases.
Anaways, over here I had the pleasure a seein the cloakin device in action on quite a few planes, but it had to get up in altitude first. geesh, boys an their toys.
For those that still think it's altutudinal/atmospherical contrailing, think again:
http://uk.youtube.com/watch?v=HOyjtiaFibw