Maybe you engine buffs could help me. I read an interesting article on early high-bypass turbofans and their need for mid-span shrouds to dampen fan blade vibrations due to the heavier titanium used.
I was just wondering, in this picture of a P&W JT9D, is the mid-span shroud the part that appears to be the two rings in fan blades? If not, what exactly are they there for, and where is the mid-span shroud?
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Photo © Jack Hannen
Thanks in advance,
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