Timeline
Some people point out a goof in FD3 regarding the headstone stating 2005 as the year of death, not 2006, and Kevin mentions Flight 180 occurred six years ago. Well, here's the thing.
The first film, takes place in the Spring of 1999, and ends somewhere between October, and November while the second film takes place one year later (Spring 2000). FD3 takes place six years later (2005) with FD4 occurring possibly during the summer of 2005. FD5 takes place during the Summer/Fall of 1998.