The story bounces between limited third person and omniscient third person. Cussler effectively uses both.
At times, he pulls back from the action and acts as an all-seeing, all-knowing narrator to provide historical information or a bird's eye view of something. This is usually done outside of the narrative (almost as if a narrator were reading in a voiceover), but he effectively ties it to the story by mentioning a character in some way. Other times he pushes in close to the action but continues his omniscient third person narration by telling the reader what a character is thinking or feeling.
Often, and especially for increased dramatic effect in climaxes, Cussler acts as a limited third person narrator, not sharing the thoughts of a person.
For example, when Summer tries to free her brother from drowning.....
