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Speed of sound is 343m/s at sea level. The blade is 113 metres, so that's a circumference of 710m.

A quick google says large turbines can rotate up to 20 rpm, so once every 3 seconds, that's 710/3 = 236m/s, so Mach 0.68

(edit) I think 29rpm is when the tips of blades go supersonic for that turbine.

"The best way to get the correct answer on the internet is to give the wrong one". I look forward to being corrected...

>"The best way to get the correct answer on the internet is to give the wrong one". I look forward to be

Depends on the site and readers. As we've seen recently, wrong answers take on a life of their own and become gospel or canon to eliminate religious overtones.

Some have a max blade tip speed of 100-180mph depending on radius and wind speed[0][1]

(I use to work on utility scale wind farms with 100+ x 2.1MW turbines)

[0] https://www.semprius.com/how-fast-do-wind-turbines-spin/ [1] https://www.windpowerengineering.com/calculate-blade-tip-spe...

Assuming you're talking about the Thunderscreech: Mach 1.18[0]

0:https://www.airspacemag.com/how-things-work/zwrrwwwbrzr-4846...