Al Gietzen wrote:

Larry; the MT salesman said;

Natural Composite Propeller Advantages

Light Weight: A lightweight propeller increases the useful load of the
aircraft and also reduces the stress on the engine and crankshaft.

No doubt the MT is high quality, good performing prop; but to call it "light
weight" reminds mean of some of the political rhetoric currently filling the
airwaves.  The MT-18 weighs in at 53 lbs; roughly double the IVO (27 lbs)
(If I dare make that comparison).

Competitive Pricing: MT Composite Propellers are priced competitively

with

their metal propeller equivalent. Competitor's composite props may cost

as

much as triple the amount of an MT Propeller.

I don't know who they consider the competition; but with an MT at
$10,000.00, and an IVO Magnum and $2150.00, and a good fixed pitch less
still; you have to wonder.

Al  Gietzen  Velocity RG 3-rotor

Well we know the IVO is a variable TWIST prop and not a variable PITCH
prop so I don't consider it competition. Nor do I consider a fixed pitch
prop competition for a constant speed prop on a high performance airplane.

The MT is a wood blade prop as one crashed here not too long ago and
I got some pieces. 99% wood with a thin layer of fiberglass.
Reminds me of IVO calling his props carbon fiber with one small
bit in there somewhere.

Time to fire up the drawing board and see if I can take some machining
cost out of my variable pitch prop designs. Perhaps a hub made from  4130 
 tubing and welded up is called for rather than hogged out of a large
block of aluminum.

BTW rumor has it in A&P circles that Hartzel is having problems with the
composite prop due to separation of the carbon fiber from the aluminum
shank. Sure would not to that. Steel is much better and titanium even
better than steel. I will stick with my steel conduit coupling for now.

Paul Lamar
 
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