Metal vs. Wood both have pros and cons
hevansrv7a said:
I gave some thought to this and got a carbon fiber over wood prop. You can restore the leading edge on a composite prop, but all you can do when an aluminum prop's LE erodes is to even out the erosion to a larger portion of the prop so as to make is smooth again (dressed out).
No disrespect to hevansrv7a, the erosion on a solid aluminum prop is a non-
issue. I guess at top speed and RPM there can be some erosion. Yes even
aluminum props wear down but we are talking 10,000-30,000 hours
of service life, extreme to normal. If you feel a well worn aluminum prop
leading edge it can feel a little rough, like it was sand blasted but the erosion
is just not an issue with solid metal props at normal cruise RPM's.
Also the "dressing" of a metal prop is really only needed if you get a rock
ding, not rain erosion. The good news is if a nick needs to be blended it can
be done on the plane. With wood/urethane leading edges or bonded metal
strips they need to be removed to be repaired. These strips have and do
continue to come off in flight on occasion. I have had two friends which had erosion
protection spit off their prop, one metal strip, one urethane strip. In both
cases it shook the plane like crazy. In the case of the urethane it only partly
came off but did do some damage to the plane when it flew off and hit the
plane. The metal strip was off a composite constant speed prop.
Nothing wrong with wood but prefer metal. Wood's advantage over metal is
light weight, smoother operations and low cost. However the cost of
some "wood props", especially ones wrapped in composites are not cheap.
They cost as much as a certified Sensenich. Wood was much more popular
15 years ago because there was just not any good fixed pitch metal props.
Fixed metal props off of slow planes, repitched and cut down, turned out to
be a bad Idea. Also one side advantage of wood is if it hits the dirt while
spinning the chance is the prop will splinter and be less likely to damage the
crank.
Now with the Sensenich available it's almost a no brain-er, almost no
maintenance, no rain issues and in my opinion will out perform any wood prop.
I know this performance issue is fighting words, but I believe it is true from
the flight test Van has done and honest performance estimates from wood
prop fly'ers The fact, metal props have an advantage with much thinner
blade thickness, making them more efficient. The advantage of a metal props
is better performance, less maintenance and rain erosion. With Sensenich
costing just over 2 bills with all the hardware they are a bargain.
I appreciate the wood prop, they are light and pretty (the ones you can see
the wood). If I was building a Day/VFR only RV-3/4/6 I would look for a used
wood prop on the cheap. However for overall value and performance the
Sensenich is the way to go IMHO.
George