I would call these incidents a series of so-called 'perfect crimes' in which the culprit is never caught.

If this aircraft was on the ground for more than 12 hours that means that sabotage would have occurred on Sunday, November 11th. If these acts always occur on the 11th of the month, especially if it is at the beginning of the work week, then it might suggest that the next attack might occur 3 months from now on Monday, Feb.11, 2002 ? One might expect a slightly different type of attack too. Modus operendi would seem to be criminal misuse of large aircraft, plus biological attacks (anthrax, NIMDA virus).

It might also suggest people with work timetables, "shift workers" are responsible. Finding out who works what shift might be a route to investigate? The same person might work night shifts Sept.10th, and Nov.11th - being in a position to plant weapons or sabotage.

I don't know about you guys but I'm getting my Christmas shopping done early this year.