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Through the Lookie Hole by Brian Christofferson
Flying a twin-engined freighter, loaded with airmail, two-thirds of the way across Montana (at night) made for many exciting stories.
https://www.amazon.com/dp/B019NPHSY8/
https://www.amazon.co.uk/dp/B019NPHSY8/
https://www.amazon.ca/dp/B019NPHSY8/
Undocumented Procedure by Brian Christofferson
Tom, a beekeeper and apiary inspector, referred to the mail plane pilot as "10 o'clock Charlie," signaling to Tom to call it a night. There were other, less flattering descriptions of the footprint left by the noisy Aero Commander on its nightly rounds.
https://www.amazon.com/dp/B00JK1VM1Q/
https://www.amazon.co.uk/dp/B00JK1VM1Q/
https://www.amazon.ca/dp/B00JK1VM1Q/