Random malfunctions should happen during the entire patrol, not just when leaving port. In my latest SH3 patrol I plotted a wrong course through the kiel cannal and scrapped the bottom. It took 1 week (half the patrol) to repair everything. And in that time I sunk a few ships wondering if I'll ever come back up. My batteries were stuck at 20% max. My hydros weren't working and I had a broken electric engine. Back at the base I saw that my hull integrity had dropped to 20%
. A very fun patrol.