Bell being conscientious of helicopters that work for a living, always considers maintainability in their design. If the yokes on the Bell 430 (or 412 for that matter) where one piece, guess how easy it would be to send a main rotor head to Angola or some of the other places in the world where helicopters get up and go to work every morning. Two narrow long boxes are better than a huge square one
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As Shawn said, having stacked yokes has no negative effect on ride (Bell 430 probably has the best ride of all) or ease of working the rotor. Experienced techs will get a 412 rotor in, in about 3 moves, as long as you’re not trying to get beat-up/trashed blades and rubber to fly together
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