This is a subject close to my heart. I could not agree more. Wood is criminally overlooked in these carbon crazy times.
Like Guppy said - no fatigue and no time limits. In fact, within the rotor world the Bell 47 could be supplied with both wooden blades and aluminium spar blades. Guess which one has a time limit? The wooden ones are on inspection only.
The Kaman K-Max heavy lifting helicopter have glass fibre covered wood core blades to this day. The Vietnam veteran Kaman HH-43 Huskie (nicknamed Pedro) also had this construction. We're talking heavy lifters here and real work horses, not some flimsy recreational helicopter.
Carbon fibre is the in material at the moment and any manufacturer throwing those words around will try to appeal to peoples fancy with this material to seem cutting edge. What most people fail to realize is that FAA certification for carbon fibre epoxy construction demands a 2x safety factor in construction (because of the unknown properties and the differences in the hand lay up and curing), whereas alu and wood only demands 1,5x safety factor. This pretty much always negates any weight saving and carbon fibre aircraft are normally as heavy or heavier than an equivalent wood or alu aircraft. Not only that, carbon fibre epoxy construction is very expensive, environmentally unfriendly and oil dependant.
But wood is a composite as well and could very easily be formed into exactly the same complex shapes and be as strong. In fact, many woods are stronger than metal. People refuse to believe that birch is 1.7 times stronger than aluminium in specific strength (strength per weight). For some reason people think of metals as stronger, when they're many times not.
Just remember the old 70's fruit bowls and how lightweight and strong they were. We used to bang, drum, jump, drive over these with our trikes and generally abuse them as kids, yet they didn't budge in shape:
Or how many complex shapes you can achieve with modern epoxy plywood construction:
But building complex shapes with wood is nothing new. It was done over 80 years ago in the still used strip wood fashion. Just like many cedar strip kayaks are constructed today (and are almost always lighter than carbon fibre kayaks, but this people also refuse to believe in). Take a look at these images of an old Deperdussin racer for instance:
Wood fits well with modern epoxy based construction. And the drawbacks that used to be there are no longer an issue, like dry rot and impact tolerance. It would be environmentally friendly, sustainable, cheaper, as strong, as production friendly and as good to do modern aircraft this way. It's just that it's not cool with wood. That's the problem.
I hope this changes.