REFLECTOR: Aerocomposite Prop

[HYTEC45 at aol.com]

In a message dated 4/4/2006 11:10:53 A.M. Pacific Standard Time,  
ajlz72756 at yahoo.com writes:

haven't  purchased my prop yet and am interested in hearing more about your 
problems  with your MT prop. I thought this was the best prop that you could 
buy and  know that this is the suggested prop to use by Velocity. If others are 
having  the same problems that you are, I sure don't want to invest 11K on a 
piece of  crap. Please tell us what kind of problems that you are  having.
After I purchased my prop in 2000, I developed a fatigue crack in one of  the 
blades.  mt said that there is now a AD that restricts the operating  RPM on 
non-counterweighted engines like mine between 2250/2550.  Even  though mt 
never sent the AD out to owners on file, I had to fight tooth and nail  for them 
to repair the crack.  After that, even though I operated the  propeller out of 
the "restricted" range, I developed massive grease  leaks.  American propeller 
who services mt told me that mt has a big  problem with grease leaks, and now 
has a another modification that is needed to  be done to address that.  I had 
that mod. done, and continued to have  grease leaks, along with bearing wear 
requiring the replacement of bearings  twice.  My average operation of the 
prop between "return for repair" is  around 44 hours.  I have under 290 hours of 
operation on the prop, and it  has been off five times.  mt admitted that the 
blade design as shipped  on mine in 2000 is not applicable to my four banger, 
so I have to PURCHASE new  blades otherwise I will continue to have 
bearing/seal/cracking problems.   This cost me 5K, as I had to pay for installation, 
along with of course new  bearings, and a pitch change yoke even though the prop 
was just overhauled 45  hours prior.  After I ran those blades for a little 
over  one hour, they developed almond like blisters on 2 of the three blade  
tips.  These were decided by mt caused by sap trapped within the wood  core.  The 
fix was to drill holes in the blisters, fly it a while to sling  the sap out, 
then seal with 5 min. epoxie.  This still left these blisters  (de lamination 
areas) on the top side of the airfoil where the airfoil is  critical.  Even 
though the prop only operated for a little over  one hour, they will not pay to 
remove the blades, but will fix them if I pay to  have the prop once again 
disassembled ($700.00) to send the blades back.   This of course does nothing 
for my time of installation and removal of the prop,  or the down time on the 
plane.
 
My prop is also an electric controllable pitch, and probably 75% of my  
additional problems are due to the electrical mechanism.  This includes  three 
pitch change motors replaced, three RPM sensor replaced, plus my time  
troubleshooting and installing these items.
 
As I sit, I am developing grease seal leaks again with the "new and  
improved" blades, along with RPM sensor problems which I was assured world not  happen 
with the new blade design.
 
mt now tells me the problems are related to either that I am  running 10 to 1 
pistons, and or I am running a light speed electronic  ignition.  They only 
tested the prop on a "standard" lycomming and since  mine is not standard, I'm 
on my own.
 
The reason that Velocity recommends the mt is because it's the ONLY  constant 
speed prop that will fit due to weight.  With the standard  Velocities, you 
could get away with a fixed pitch prop.  With the XL and  /-5 a constant speed 
is a must, and they (Velocity) would not have a  viable/safe product in the XL 
line without one.
 
I know that Velocity is very interested in the aerocomposite, and another  
option may be soon available.  I hope so.
 
TEC
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