Do you have citation for this? I looked on Google and it's a jumble of conflicting reports. My reason for doubting is that modern turbines turn slowly in rpm,

Do you have citation for this? I looked on Google and it's a jumble of conflicting reports. My reason for doubting is that modern turbines turn slowly in rpm, but the blade tips are still moving extremely fast. Like, just barely sub-sonic fast. So I could well believe that might still be an issue especially for large birds.