From: Night Over the Solomons by Louis L'Amour. Bantam, 1986.
In this story from a collection of aviator tales, Grumman Goose pilot Turk Madden is sent to locate a Russian comrade's plane, lost in the mountains of Siberia. Madden finds the wreckage and theorizes the plane was shot down, the pilot murdered as he fled from the crash.
The morning after reporting to his Russian superior, Madden finds himself accused of his friend's murder. Boldly escaping from his cell, Madden tries to find the real traitor. A fine, twisty yarn from an old-fashioned storyteller.