Every two or three years one of these sinks and usually takes several people with them. No one seems to have mentioned that these amphibious vehicles are at least 70 to 75 years old and have not had spare parts made for most of that time. I wonder how many of them have had unsafe repairs (to cut corners) made during that time. They were not made to last forever. They were made to be turned out faster than they could be sunk.
Mechanically, a lot of them are newer than you think. The only “original parts” on these tend to be the hull.