Smitty Two wrote:

Sir, I hope you will not feel singled out by me, but how does abusing
the man's name lend credibility to what appears to be a reasonably
scholarly hypothesis? This is only one example of what I mean when I say
I don't give much credence to either Mr. Fetters or his detractors.
Sarcasm, rudeness, disrespect, arrogance, snottiness, and all the other
exhibits of hostility that permeate both sides of this discussion - and
so many others here - may bring self-righteous snickers to the
like-minded, but do *nothing* to persuade your opponents or the neutral
lurkers.

First of all, I want to thank you for pointing that out. You are
correct, I have rewritten it:

Cicarre's CH-7's blades were better, they didn't bow like a banana.
The Mini500's blades were bowing forward as you go from the root to
tip. This changed the pivot point for the baldes, imagine taking a
straight bladed sword and rotating it, the tip and the rest of the
sword pivots at the pivot point. Now imagine taking a curved sword and
rotating it the same way, you'll notice that the tip stays at the pivot
point as well as the root, but the remainder of the sword will rise or
fall due to the curve.

The CH-7's blades were fabricated better, they were more uniform or
should I say more consistent than what Fetters was able to produce.
Being more uniform, and of the shape that they were designed, they were
easier to track and balance. This resulted in a smoother flying ship.
Fetters couldn't get the blades to come out as designed. They were not
consistent, they bowed where they shouldn't have and this resulted in
problems when trying to track and balance the blades. I remember that
Gill had a hard time getting the baldes to fly smoothly.

I think this fact alone (bad blades) resulted in inefficient rotor
system, unlike propellers, the blades of a helicopter changes pitch
continously as it goes around the vertical shaft, with bad blades, this
resulted in "shaking" or unsmooth helicopter. The shaking caused the
frames to crack! Again, instead of addressing the problem (bad
blades), Fetters added more metal to the frame in an attempt to beef up
the area prone to cracking.

Since the blades were not as efficient as the CH-7's blades, the engine
had to work much harder to get the same lift. That's where Fetters
came up with the bandaid fix, the PEP kit. Instead of tackling the
blade problem, he overworked the engine by PEPing it up. CH-7s didn't
need to be PEPed up.

That's my two cents worth.