I would suggest
have two tables in the one File
One table would be 'Missions" tables with all its layouts
One table would be the "Incident" with its layouts
These are quite separate until they are linked.
In each of the tables you create is a matching field for the Job number or mission number.
You link these in the relationship boxes of each table (Manage Database)
So when there is an incident you copy the 'code' from the 'mission' mission table
and paste it into a New Record in the 'Incident' table code field.
(There are ways to automate this)
This links the incident to the mission.
You will need to create a text box field in the 'incident' for the report. But you use use the Date and time fields from the 'mission' table. but an extra date field for the date of the report.
There are various ways in which you can view the incident report in the Mission layouts.
Also look at the help menu about relationships.
You might want to read up on "Portals" in filemaker help. This is one layout object you can place on your missions layout and use it to log incidents in the related incidents table. Set up correctly, it'll automate the linking process Dumiya describes.
You can log incidents not associated with a given mission directly on your incidents layout and simply leave the key field (Probably a MissionID field) blank.
That's awesome guys... thanks. :)