Reddit mentions of The Long Way Home - Revised Edition

This isn't some hypothetical /r/aviation pissing contest, go and read the relevant passage from Dover's book. The reason they were leaning the mixture was to increase endurance. Emphasis is mine.

>"How’s it look, Swede?" Ford asked. "So far, so good. Cylinder head temps seem to be holding. But we’re flying full rich. We’re going to have to lean it out for best fuel range."
>
BANG! The sudden sound filled the cabin and the Clipper shook as though it were in the grip of a gigantic storm. BANG! Again.
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"Backfiring on Numbers Two and Three!" Johnny Mack called out. "Those cowlings are shaking like Jell-o!"
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"Back off the mixture, Swede!" Ford shouted. Rothe quickly moved the mixture controls toward the rich side of their range. Just as quickly the banging stopped. But the cylinder head temperatures remained just under redline.
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Once again the mixture controls came back. Once again the manifold pressures increased and the cylinder head temperatures rested within a degree of the forbidden redline.
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Then: BANG! BANG! The Clipper shook as though it were a rag doll in the hands of a very active child. Quickly, but with more control this time, Rothe eased the mixture controls back to just under the mark where the backfiring would start. "That’s about the best we can do," he called out. "We can stay below the backfire point, but I can’t guarantee the head temps. They’re just about out of normal range for long-range cruise."

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