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-   -   WHICH HARTZELL PROPELLER MODEL? (https://vansairforce.net/community/showthread.php?t=177035)

Jetmart 11-19-2019 04:09 AM

WHICH HARTZELL PROPELLER MODEL?
 
Van's is showing both a 72" and 74" C/S prop for the RV- 14 & 14A for the 390Hp. What are the pros & cons of each option. They are both priced the same?

jeffreyuh60 11-19-2019 06:12 AM

RE: Which Hartzell propeller model?
 
Glen,

I called Hartzell a few weeks ago with the same question. They had me contact Vans. Essentially, vans stated that the 72" is for both the taildragger and the tri-gear aircraft. The 74" prop is not recommended for the taildragger RV-14. For what it's worth, I ordered the 72" prop.
I hope this helps!

Jetmart 11-19-2019 06:15 AM

I had heard that before but surprised to see both listed on Van?s site for the taildragger. I guess they?re concerned about prop strikes??

Shado 11-19-2019 06:29 AM

When only considering an RV14-A (which can use either it seems), any thoughts on pros and cons on choosing one over the other?

kbalch 11-20-2019 12:51 PM

Quote:

Originally Posted by Shado (Post 1387280)
When only considering an RV14-A (which can use either it seems), any thoughts on pros and cons on choosing one over the other?

All else being equal, at any given RPM, greater blade length will yield greater thrust. I chose the 74" version for my -14A.

FWIW, when I spoke to Mike Seager back in September, he agreed that the 74" Hartzell is the best-performing prop for the -14A.

Jetmart 11-20-2019 01:49 PM

Why not put in on the 14 then? Is 1" less ground clearance really going to be a factor?

kbalch 11-20-2019 01:59 PM

Quote:

Originally Posted by Jetmart (Post 1387604)
Why not put in on the 14 then? Is 1" less ground clearance really going to be a factor?

Apparently so. With the -14's tail up on takeoff, it won't take much over rotation to place the prop disc in closer proximity to the ground than the -14A's in its normal three-point attitude. Not to mention the tailwheel version's entirely different main gear legs, the springiness/compressibility of which (on, say, a poorly executed wheel landing) might also bring the longer prop closer to the ground than desired.

Discus2b 11-20-2019 05:19 PM

This topic has been covered in the past here on V A. Basically, prop length was reduce for the 14 to satisfy the drop test ground clearance requirements, I believe.
I learned this after I received my 72? prop (14) and was a little pissed. I would have preferred the 74?. I asked Hartzell if I could exchanged my unopened 72? prop and they said once shipped it is considered used.
I advise, if you are a good pilot and feel you will not crash land or over rotate
by an insane amount, go with the 74?. If you are a below average, have a tendency to lose control, wear a watch over 1 lb, and get lost on cross country flights.....go with the 72?.

R

rvbuilder2002 11-20-2019 08:34 PM

Quote:

Originally Posted by Discus2b (Post 1387664)
This topic has been covered in the past here on V A. Basically, prop length was reduce for the 14 to satisfy the drop test ground clearance requirements, I believe.

This is the correct answer.

Don E 11-21-2019 04:13 PM

Went with the...
 
72? on my RV-14. As strongly recommended by Vans. I have no way to know what difference another inch of radius would make, but I am completely happy with how it performs. 101 hours now....


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