Dear Larry,

As to a list of boats that went missing...

In our DUIKBOOT-database (see [historisches-marinearchiv.de]) you can
in the search mask enter a time period and select for instance the event "sunk, cause unknown" (almost at the bottom of the drop-down menu with events).
One can also select as event "Last message/signal from the boat".
Both these events are in drop-down menu with events under the sub-heading "End of the boat".

To get the english description of events, first select the U.K. flag at the top lefthand of the screen with the search mask.

DUIKBOOT is a living database. There are still alterations, additions and corrections, yes, but it covers information from a good number of sources.

Best regards,
Walter