Not sure about your mod layout so I can't comment on that, but I'll get the ball rolling in the suggestion department by asking about your TC. If it's too high when you get close to land, (say within 50 km or so), it can often lead to a CTD.
If your TC's okay, then there could be an issue with the campaign layers or even a corrupt save. Best way to test is to load up a new mission and head for Scapa to see if you can reproduce the crash with your current configuration. If it doesn't go down, then your mod loadout is probably stable, whereas if it does, then suspicion falls on the save.
Also, you might want to post your mod list so we can help a bit more. Good luck in getting it sorted!