The "Sky Detectives" are ace pilots Jack Ralston and his pal "Perk," who help the Secret Service unravel baffling cases. This volume contains the complete 6-book series, originally published between 1930 and 1931:
1. The Sky Detectives 2. Eagles of the Sky 3. Wings Over the Rockies 4. The Sky Pilot’s Great Chase 5. Trackers of the Fog Pack 6. Flying the Coast Skyways
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