Both are excellent publications.
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"Handling the Big Jets" (last edition) covers all early jets (US and British) and includes a study of the original 747 Classics. Excellent reading for new airline pilots. "Fly the Wing" is primarily a detailed study of the flying qualities and performance of DC9-30s, based on US FAR 25 Certification and FAR 121 Operations.
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I recommend both books as a "must read" to pilots who are starting their "jet" transition, regardless of "size" of aircraft they will be flying.
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Happy Contrails