I'm looking for the standard weights of the major
components in a 13b engine to do a weight analysis.

My goal is to lighten the engine by at least 30% and
at the same time strengthen the parts.

AM-SC1 is a new magnesium alloy (mg matrix) with a
32%
weight reduction from aluminum. Temperatures can run
higher as well so cooling may be adjusted.

The rotor assembly cannot be lightened significantly
just yet. Custom shop has taken only 0.2 pounds off
the rotor.

The casings are the prime target.

Fuel injected or carburated, I'm looking at the full
aircraft engine without the prop. So if you have a
special exhaust manifold that is lightweight let me
know.

David Mathes

>From Don Dunbar.

Paul Lamar ...No rotor no motor.

Wow. Thanks!!!

David Mathes

Hi David;

Have you looked at Al-SiC to replace the iron bits:
http://www.mc21inc.com/
or foamed metals using ceramic microballoons?

Cheers
Cary

Cary

I wonder about the toughness of this material.  Wouldn't a non homogeneous
material like this be prone to create stress risers in an engine housing
application?  I'll send the info on to our Tokyo office and see what the
engineers think.


DougFir

Hi Doug;

Homogeneity is an issue with foamed plastics, it would depend on the
process. You are essentially dealing with a "new" material whose
(reduced) physical properties must be determined.  Products may need to
be re-engineered to take full advantage, with say thicker skins to take
the same load, but the thicker, lower density, skins are stiffer and
reduce local buckling...
High stress regions such as bolt holes may need hard point inserts.

The nice thing is some of these materials can now be cast.  Al-SiC has
properties that are looking more like cast iron.  I'll have to look at
AM-SC1.

As a teaser for David, a physicist friend (whose specialty is coatings)
discussed the possibility of foamed Al at 10% of the weight, it would of
course be uber expensive...

Cheers
Cary



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