Hartzell Scimitar propeller Pirep

[OR75]

Installed a new Hartzell scimitar propeller on a 77J. A few observations:

Yellow arc on tach has no reason to be there indeed.

Operation sound smoother although I think I will do a dynamic balancing sometime soon

The oil temperature appears to be lower. ( the temperature needle used to be right on the vertical line of the F before, and it is now well below that). Better cooling because the bulkhead change ? The CHT is a little lower too.

Speed seems to have increased about 2 knots as reported elsewhere , but that's just me dreaming or justifying further my spending

[Cody Stallings]

You bolted on the finest propeller offered for Mooneys. I strongly recommend a Dynamic Balance. What part of the country are you in?

[OR75]

You bolted on the finest propeller offered for Mooneys. I strongly recommend a Dynamic Balance. What part of the country are you in?

NorCal

[Bob_Belville]

Cody, I had my Scimitar (new in 2009) dynamically balanced after installing a PowerFlow exhaust. Now I've had a prop strike and New England Prop has repaired the blades, etc. I suppose the prop needs to be rebalanced?

[jetdriven]

The prop shop will static balance the prop, but dynamic balance is done with the engine running.  It isnt required, but some airplanes get remarkably smoother when you do.

[Bob_Belville]

Byron, I had the prop d.balanced by the prop shop in Burlington NC while I waited. I will do it again when I get the plane back home. (I could not tell much difference at all last time but PFS doubles their warranty if the prop is DB'd. And it might make more of a difference this time. I think I'm loosing 1/4" off the prop.  

[bdjohn4]

I assume you have:HC-C2YR-1BFP/F7497 

Can't wait to put one of these scimitar props on my IO-390 conversion. I am very happy to hear you are getting better cruise kts with the scimitar, which I understand to be heavier and slightly detrimental to speed, but so insignificant that it is difficult to measure. Yes, IMHO an engine is too expensive not to spend a little $$ to have dynamically balanced. I did it as part of the PowerFlow warranty but would do it even if that wasn't a requirement.

http://www.vansairforce.com/community/archive/index.php?t-21362.html

Excerpt:

"gmcjetpilot  09-12-2007, 06:07 PM

I had a long talk with hartzell.

The 7496 was their first go at it. Its a fine blade and a little thinner than the 7497. As they developed the 7497 for the IO360 angle valve they realized it would work on the 180HP as well with out the small limitations.

I asked about weight and loss of performance?

Yes the 7497 weighs a little more but as a precentage of the props total weight its very small (no specifics given).

Performance? Talking to the engineer that did the flight test development for the 7497 the there may be a slight hit on speed, but its too small to measure. Hartzell has the same challenges in getting good flight test data like we all do, especially when trying to compare two different props.

If you have the 7496 blade its still rocks and you do get that slight weight advantage and minor edge on speed. The limits on the 7496 are pretty minor. So if you have a 180HP 360 you have the choice of either. However if buying new today, the 7497 with no limits is the way to go as Hartzell recommends."

[OR75]

maybe my memory is failing me but i believe i remember seeing in this forum someone having to sell his scimitar prop because of incompatibility with the PowerFlow system

[Cody Stallings]

Yes Bob, you will need another dynamic balance. Anytime you fool with the Propeller, Cylinders, Mags an spinner, it's a good idea. Cause a change in any of those 4 thinks can throw off the balance.

When Doing the runs while your propeller is being balance be sure an lean to try to make it as smooth as you can. Cause take it from me, it's a pain in the tail to try an balance a propellers when it's slobbering rich.

[Cody Stallings]

OR75, Eric at Golden State propeller can fix you up with a Balance. Good guy to deal with.