10) was disguised as the Japanese carrier Kaga  to film scenes of aircraft taking off and landing. It was fitted  with a false bow to disguise the catapults. Although it appears as  though steam is leaking from the bow, Japanese carriers actually  used steam to indicate wind speed and direction over the bow. The  steam trail was lined up with the painted white lines on the bow. It  was unofficially named "USS Kaga" for the duration of filming. The  USS Enterprise seen entering Pearl Harbor at the end of the movie is  actually the USS Bon Homme Richard (CVA