Originally Posted by
jgracco
I just got off the phone with an engineer I know in military aircraft research who works with full scale engines. He took one look at the pics I sent him from this forum with the curvature of the blades (inward) and suggested that this could be flutter. Apparently there is a resonant frequency for every motor and in full scale motors there are controllers designed to avoid whatever that rpm range is altogether. Wren could either experiment with different length intakes or calculate the length of an intake needed to shift the flutter to an RPM range that is not problematic.
Sounds like a reasonable solution. I wonder why wren never thought of that? Or did they just do no research at all? Or did they try various solutions, but non of it worked? Why won't they come out and tell? It took people on this forum only 3 days to get to a possible solution, wren has done nothing the past 5 years to resolve the problem. I am willing to put this theory to the test, but wren will not repair my engine. They reckon they don't have parts for it anymore!
So how do we get wren to respond? Who will speak for them?