Clint Eastwood's voice is dubbed by another actor.
Kerama Retto is mentioned as the destination of the Bellinda after she is seriously damaged by a kamikaze. This island, about a dozen miles southwest of Okinawa, was taken by the 77th Infantry Division at the start of the invasion, and used as both a staging area and an emergency anchorage, exactly as shown in the movie.
The name Bellinda is a fabrication. No ship ever sailed with the hull number of APA-22. The USS Joseph Hewes (AP-50) was designated for reclassification as APA-22 in early 1943, however she was lost in November of 1942 before the change occurred. As the numerical sequence of attack transport hull numbers had already been assigned, the number was not reissued.