There are arguments for and against cold water preservation, but I'm going to go with cold water being a better preservative agent. No reason other than the water around here is cold.
Here's what's left of a 1942 takeoff accident with a PBY at the old USAF base at Mingan, just down the road from here.
PBY found at Mingan.
A lot further north at Beechy Island in the Arctic, here's a wreck of one of the ships that searched for the Sir John Franklin expedition. It's better than 150 years old and still in pretty good shape, comparatively speaking.