What is the author's style in Tunnel in the Sky by Robert A. Heinlein?

The point of view of this novel is third person omniscient. The narrating character is Rod Walker, a high school student who is taking a survival course in high school in order to get a leg up on his desire to lead new colonies onto new planets. As the main character of the novel, it is important that Rod be the narrator. The choice of third person omniscient allows the reader to develop a strong relationship with Rod, resulting in the reader's concern for what might happen to Rod. However, the third person point of view, as opposed to the first person point of view, allows some degree of separation between the reader and the narrator, allowing for the author to occasionally move away from the main character and inject information or comments that help the reader understand the plot of the novel more clearly.