Comments by "Titanium Rain" (@ChucksSEADnDEAD) on "MP7 vs B-52 bomber fan blades" video.

  1. It's for expansion. Vibrations are handled by balancing the blades, you use blades of equal weight on opposing sides to balance each other. Letting them loose would not balance the assembly because unequal weights would still cause the "wobble" that reduces bearing life and may cause the blades to scrape against the casing. So the balancing operating is done by figuring out which position of the assembly is the heaviest, and put a heavier blade on the opposite site to counter. Then keep doing it until there's no more "heavy" spots. Source: I have a relative who's an aircraft mechanic.
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