The beluga whale is a beautiful mammal but the Beluga, as an aircraft, is truly uuuugly.
But I love this aircraft because it's designed to look like a sea creature both types are familiar with aeronautical miles. The Airbus Beluga is has amazing capabilities.
It's used to carry outsize cargo such as Airbus aircraft parts, even whole helicopters.
If you like aquatic-inspired aircraft how about the Pregnant Guppy or Super Guppy (below)?