The reason flights have been intercepted, in the Maastricht airspace at leasr, has been due to lack of R/T contact. From memory, in the last year 2 actual intercepts and a number abandoned ( too great a distance involved, or R/T contact re-established. )
Post 9/11 we are required to inform the military of any aircraft in radio failure, this info is passed to air defence who make the decision to intercept or not.
The reason that the fighters get in so close is to observe if there is activity on the flight deck. In the past we had two occasions when there was none observed, the Lear {Snoopy?) which eventually crashed off Iceland when presumably the fuel ran out, and the East German fighter whose pilot had ejected over East Germany but whose fighter almost reached the Belgian French border before crashing, killing one on the ground. In niether case was there any question of the interceptors firing.
If you fly through busy airspace, and either the frequency seems quiet, or you have not received any atc instructions for some ten minutes, try giving a call for a frequency check - sometimes we forget to transfer youand you are now in another unit's airspace, you may even be on the wrong frequency. It is a lot less work for us on the ground to answer a simple question than to vector, climb or descend conflicting traffic and instigate the interception - and probably a lot less work for you explaining why we have lodged a report on you for not monitoring the frequency
Lon More,
Here before Pontius was a Pilot or Mortus was a Rigger