During the last Africa trip of a German pilot magazine, a hyena developed a taste for an MT prop.
The advice from MT was to go to the next home depot and buy wood filler to patch up the propeller.
The final repair was done inexpensively by MT. Now do that with a carbon fiber prop… There is a good reason why MT props are extremely successful and carbon fiber props are not. They are just way too expensive with not a lot of advantages.
Normally Silvaire advocates technology that can be fixed with Neanderthal technology in exchange for 2 mugs of beer but suddenly the most expensive, difficult to repair, relatively unproven carbon fiber props are the way to go?
No wooden structure visible on my MTV-14D. Also I have visited the production facility two years ago and made many pictures. Will post some when I find them! I am sure that it’s several layers at least around the parts near the hub.
Some pics from the MT production
Harder and stronger wood is used at the hub to provide the necessary strength
the milled propeller blades
blades are beeing covered with carbon. other types use glass fibre
these blades were covered with several layers of carbon
one of the ready blades for my four blade MTV-14D
@ Achim: Impressive field repair
achimha wrote:
Normally Silvaire advocates technology that can be fixed with Neanderthal technology in exchange for 2 mugs of beer but suddenly the most expensive, difficult to repair, relatively unproven carbon fiber props are the way to go?
Obviously I am prepared for that attack 
Most people including me operate according to the rules when needing propeller structural repair, and almost any propeller repair under FAA rules must be performed by a repair station, greatly diminishing the value of A&P field repair. The most expensive thing I’ve ever paid for on my aircraft was an overhaul of the MT propeller by an FAA repair station. Happily, engines and structures do not fall into the same category in a reasonable regulatory regime and in those cases the value of field repair is huge. Also, carbon fiber props have been in high volume use for quite a long time, about 15 years that I’ve been watching.
As a more general comment, one of the characteristics of computer people is that despite their borrowing the word ‘technology’ for their own purposes in a naive and uneducated fashion, they don’t typically have a strong understanding of technology outside of their narrow area. The point of real technology is to address a problem and solve it in the best way, not to fall irrationally in and out love, over and over again like a teenager.
Alexis wrote:
Some pics from the MT production
Showing wood bladed propeller blades with a non-structural composite weather shield. The main difference from 1930’s style wooden props is that instead of varnish, they use a thin layer of composite instead. The also appear to glue the wood blade cores together in a somewhat different way that a traditional prop, which I’m sure is helpful to the structural design but its still wood with the limited strength of wood.
Thanks for the photos. Here is a carbon fiber propeller that is in wide use. In addition to the hollow fully carbon composite blades, note how the tip of the 3-D electro-formed nickel leading edge wraps around the curved tip of the blade, inserted into a molded recess that exactly fits its 3-D shape. Also note the lack of rubber cover at the root of the blade.
A acquaintance was running a very similar propeller at the World Aerobatic Championships in Italy a few years ago and was approached by an MT representative who asked him “why aren’t you using one of our propellers” as though he had made some mistake! My friend replied simply “I don’t like splinters”. The guy apparently said nothing, and just turned around and walked away
It is several layers in some places and it is not only a “weather shield” but has influence on vibration aswell. The surface is completely smooth and at least on my prop the surface looks just like on the Hartzell carbon prop. Mine also has the (glued on) stainless steel leading edges that can easily be replaced in case of damage.
Other than that: Wood is the perfect natural high tech material for a propeller. I also have pictures of repairs done by MT … every blade, no matter what happened can be repaired for a fair price.
When I got the prop it was actually only a test and we had agreed that I bring it back after a couple of weeks after I tried it. I lied it so much the first day that I decided to keep it immediately.
Borrowing loosely from Cocodile Dundee:
That’s not a wooden propeller. That’s a wooden propeller!
A series of four videos from the times when men were real men, pilots were real,pilots, and propellers were real propellers
My friend replied simply “I don’t like splinters”.
I think there’s really no topic in aviation that’s free of prejudice. Sure, the 3-blade Hartzell Carbon prop is a good product but it costs $ 10.000 more than the 4-blade MT that has some advantages over the 3-blade aswell and can be repaired for relatively small money. Wood is a great material for props.
A very high percentage of world class aerobatic pilots flies MT props: Lighter (than metal), less vibration, cheaper repair, much lower inititial price than carbon prop.
The fellow I mentioned has more piloting time in one particular category of aircraft than any other pilot in the world… and most of those have wood propellers. He’s not prejudiced, he was just responding to the guy’s cocky attitude… and it had the desired effect
As I’ve now mentioned three times, and am trying to clarify, carbon fiber bladed propellers are sold by Whirlwind for about the same price as an MT prop. They are widely used on aerobatic aircraft.
There is no Whirlwind propeller for the SR22 or for the aircraft with big bore engines.
A ground adjustable 2-blade Carbon prop for a LSA or Cub cannot be compared with the 4-blade MT constant speed prop for the SR22 with TKS deice.
