Gents -
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I am in complete agreement with 411A´s opinions regarding the difficulty to fly an old 707 with parallel yaw damper, when you are to disconnect that yaw damper before landing. Long time since I flew the "old 707 models" but recall that it was one of the last items on landing checks.
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Early Learjets (23/24) were similar in being extremely unstable in final, when the yaw damper was required to be OFF, as they also had a parallel yaw damper. In these Lears, a dead Y/D was a NO GO item...
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If you want "to see" how such 707s were doing in short final with a parallel yaw damper "OFF", and how unstable they were, try to locate the short movie made of the remote controlled 720-061 of the FAA that was crashed in the early 1980s in California. The last 300 ft AGL depict the very unstable approach, obviously piloted by remote control - but definitely not by an experienced 707/720 pilot" - and illustrates how difficult they were to control.
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Happy contrails