Originally posted by kingwoodbarney
First of all, let me say that I agree with you guys.
But what I am noticing on the airport is something very different.
I am seeing ATR's and DO328's with these incredible multiblade simitar looking ginsu props with 5 or more blades. (I'm not sure how many blades, but its a bunch).
This seems to be the trend lately and in the case of the DO328 I have seen ground speeds in excess of 400 knots. These things are almost like unducted fans.
Is it because these new generation turbines produce THAT MUCH power? And another thing, these puppies are super quiet!
These props are used to reduce noise.
They only do like 700 to 800 rpm. That's the noise reduction part. Now, in order to convert shaft power (these turbine engines generate like 5000 hp) into thrust with a prop spinning that slow, you need a lot of blades. Simple...at least the theory. In practice, a lot of engineering is needed to achieve succes in this matter.