sunderland flying boat (origin of the name)

I'm pretty sure that Sunderland was the last name of
one of the designers of the sunderland flying boat. I
can't find any source other than a Wikipedia article
concerning the origin of the name.
(http://en.wikipedia.org/wiki/Sunderland), This article indicates that
that the craft was named after the city of Sunderland. I believe this
is incorrect, however. (I remember my grandfather telling me stories
about
meeting Sunderland and talking about the flying boat he designed.)
Could someone verify the origin of the name for the Sunderland. Thank
you for your time!

Edward Senft