Yesterday in port I installed Campains from TM 1.4. After which I did a photo recon for BB Yamamoto; found, photoed and sank same. By the time I got back to port I had sank 12 merchants, several by gun fire, dodged two convoys and a task force for lack of fish.

The saved file for that mission was 5.7mb.
My save files have been running anywhere from 3-6 mg. Today I get photo recon carriers off china coast. I sank one merchant off the coast of Japan, not yet to china. I saved file to go eat (no replay checked).
I checked the save file due to slow loading. I found 255 mb saved file from Midway to Japan coast.

This has never happened before. For this mission I ran at ahead standard on the surface most of the way, did two practice dives, no air attacks and an easy straight setup on the merchant.
I used campains from Favored to Taste 2.5 with patch 1.2 and did not have a bigger file than 6 mbs which included three completed objectives.
I restarted the Photo Recon Carriers mission from port and deleted the 255 mb saved file. I am going to run same course and speed and see if anything changes, will report back.
Any new ideas on what might cause this???