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Hartzell Composite vs. Whirlwind Composite

KatanaPilot

Well Known Member
Let me begin by saying I have searched and read the very old posts about Hartzell vs. Whirlwind. Those posts are approaching 10 years old and they mainly talk about Hartzell metal vs. Whirlwind composite.

We are trying to decide on a prop for our RV-7A (Titan IO-360 9.5-1 dual P-mags).

My son and I talked at length with Hartzell at Sun-N-Fun. Having owned a DA-40 with the Hartzell wide chord composite prop, we have a good bit of real time experience with that prop operating in rain and off our turf runway at Mallards Landing. It was outstanding and had very little wear over 4 years - despite being a much larger two blade vs. the MT three blade on our earlier DA-40 (which did not wear very well).

The Hartzell folks were very knowledgeable and honest about their prop. They know it's more expensive than most.

The Whirlwind sales rep knew very little about the construction of their propellers and hubs. It was hard to get a warm fuzzy after his comment "my friend across the street owns the machine shop where we make the hubs". I'm sure many have great experience with this company and I'm not trying to slight Whirlwind - other than to say it would have been preferable to have someone technically savvy manning their booth. I would also like to have seen a cross-section of their propeller.

I'm not trying to start a propeller war. That's been done here before.

I know the Hartzell is an outstanding certified propeller, performs very well and is priced accordingly.

What I don't know is how well (in comparison) the Whirlwind props and hubs are made and their longevity under real-world conditions. They do look really nice and can be painted to match the airplane when you order. That has a certain appeal, but is not the biggest motivator. The lower cost, flat rate overhaul is nice, too.

The difference in up-front price is several AMU's. That being said, price is not the primary concern, either.

My gut tells me the Hartzell will perform better on take-off, climb and will be close in cruise. It is probably better made, more robust and damage tolerant. Hartzell is well known and will be around for a long time. The Whirlwind looks better, the wide chord blade (200 series) probably performs similarly and costs less. The testing, construction quality and longevity of the prop (and the company) are a complete unknown to me.

Anybody want to weigh in?
 
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Its going to be difficult to compare them performance wise as there are very few who went from one to the other. Having installed and flown with a dozen of the Hartzell composites, and written about them extensively here, we have not seen a single issue with them over thousands of combined hours. Like you said, more expensive yes. There is a reason they are the best and most reliable prop on the market. You might also read about folks and their send backs of the WW props on service and inspections. Just doing that once kills the price difference for me.
 
Aerobatic prop on Pitts

Hi,

I am considering a whirlwind for my 4 so have been doing a bit of research. My friend has just put one if their aerobatic props on his Pitts, it's a work of art!

He saw an increase in cruise of 15knts over his previous prop, and an increase in climb. I will try to find how many hours he has on it now.
 
Our experience was the same

Its going to be difficult to compare them performance wise as there are very few who went from one to the other. Having installed and flown with a dozen of the Hartzell composites, and written about them extensively here, we have not seen a single issue with them over thousands of combined hours. Like you said, more expensive yes. There is a reason they are the best and most reliable prop on the market. You might also read about folks and their send backs of the WW props on service and inspections. Just doing that once kills the price difference for me.

I've basically come to the same conclusion, but I'm just looking for some real world data that might drive me to the Whirlwind. If there was information that indicated the performance, reliability, longevity and durability of the Whirlwind was close to the Hartzell, that could sway me. Right now, I think it's only price and appearance that are better. That's not enough for me.
 
I can't offer a comparison of the two, but I have had a constant speed Whirl Wind on my Sportsman for a little over 100 hours. I live in the Pacific Northwest so while I don't intentionally fly in rain, it is hard to avoid. The only "erosion" problem I have had is that the Whirl Wind stickers peeled off almost immediately, well at least part of them did. Other than that there is no noticeable wear on the blades.

The only perhaps odd thing is that the prop has to come off and go in for a teardown and inspection after 650 hrs.

If I understand the company correctly (and I freely admit that I may not) Whirl Wind is essentially 2 companies. One makes the fixed and ground adjustable props and the other makes the constant speed props, but the blades for both come from the same place.
 
I have a Whirlwind 200RV.

As near as I can tell, the blades are solid carbon fiber. Extremely well made blades.

I can talk a little bit about the aerodynamics of both props.

The Whirlwind prop is designed using classical propeller theory with an extension to correct for the flow disturbance of the nose of the airplane. This is a nice approach. Classical theory tends to lead to designs with the very small tip chord. This is perfect for low-speed propellers, but is perhaps not best for higher tip Mach numbers. The Hartzell design reflects experience with dealing with higher Mach no. flows, where it is better to have a wider chord airfoil that is not working as hard, to provide the same lift, but with less compressibility drag, at the expense of slightly higher skin friction drag. We cruise with tip Mach no. of about 0.70 which is right about where the dividing line is for these two philosophies. Which explains why they have very similar performance for our use. If you are going to race and have visions of running at 2700 RPM much of the time (M=0.77) then I would recommend the Hartzell.

I am generally extremely happy with my 200RV, but....

At about 300 hrs, it was spitting so much grease that I pulled it for overhaul.
I know of others with the same issue.

The Whirlwind folks said that they have since switched to Viton o-rings, and expect to have no further problems with broken o-rings.

During overhaul, the folks at Stockton Propeller found some of the internal components of the hub excessively worn, pitted, spalling. Bearing races/retainers IIRC. They were stunned to find this on a 300 hr propeller and speculated that it might have been assembled with used parts. I have no way to know one way or the other, and don't mean to cast shade on Whirlwind. Just the facts.

With replacement parts (including Viton o-rings) and labor, the overhaul was close to 25% of the initial cost of the prop. That would come close to making up the cost difference between the props.

Time will tell if the new parts and new o-rings hold up. It has 440 hrs on it now.
 
The constant speed Whirlwinds (Ohio) are based on a McCauley hub, that WW machines in house for the CS props. The blades (as I understand) are still made by Jim Rust's company (Whirlwind California) and are hollow, but are all carbon reinforcement, not a different mix like the Hartzell.

This video is old, but should help understand how they are made.

I chose the Hartzell composite after visiting both, but the choice is for each to make. The grease issue for WW (as told to me by the engineer during my visit) was the result of a lube change incompatible with the seal. While it can happen to any company, WW is small and does not have the resources for controls as encompassing as Hartzell. However the same can be said for Vans Aircraft. The WW does seem quite efficient in cruise. Probably no measurable loss between the two companies. Thrust is another matter.

Beware of the Hartzell blade position at full pitch. That wide cord brings the blade swing back considerably.
 
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Beware of the Hartzell blade position at full pitch. That wide cord brings the blade swing back considerably.

By that I assume you mean that with the wide chord, at coarse pitch the trailing edge of the blade moves aft quite a bit and could interfere with the cowl?


Interesting to hear that you think the o-ring problem was an incompatibility with the lube. The WW folks didn't say that at the time, but did say that Viton o-rings would solve it (which typically means either a chemical issue or a temperature issue). Fingers crossed I won't need another rebuild for awhile.

I believe it is correct that WW uses a McCauley hub design, but makes them themselves.
 
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good service and performance for me...

My WW200 was just overhauled after about 1300 tach hours... never had any grease leakage and the prop performed great.

I did a re-blade on the overhauled hub to the new HRT blades that are shaped a bit like the big hartzel.

At the closest point on the cowling (right side from the line of thrust) I have just shy of 1-1/2" clear with the blades flat. From Low to High pitch there is about 21 degrees of rotation which moves the trailing edge of the prop aft about 3/4".

Initial perceptions after seven hours of flight time:
There is notably more thrust.
Early testing suggests more climb and top end...
Detail testing will begin when we get better weather...
 
Thanks for the replies

All good information to have. The more I read, the easier the decision becomes for me. Thank you.
 
Another option

Another option to consider is to get a McCauley prop hub and get Mr Catto to make you a set of his blades for it. Wished he made blades for the Hartzel hubs.
 
Hi Krea,

I don't have the engineering expertise of Steve Smith but I do have real-world experience with both props. I flew my RV-8 with a WW 200RV for about 1500 hours. I was given a Hartzell composite, wide blade prop when Hartzell sponsored our Team AeroDynamix. I paid about $7K for the WW and I was told that the Hartzell cost north of $12K!

I did have a bit of grease slip past the blade seals on the WW but that was solved at the 650 hour inspection with different seals and an improved grease. I called WW to set up the second inspection at 1300 hours and they asked me to wait until 1450 hours as they were considering a 800 hour inspection cycle and wanted to see if the extra time would reveal any problems. Wear on all components was negligible at both inspections. I was VERY pleased with WW customer service and pricing.

I have not put enough time on the Hartzell to need an inspection. I only have about 600 hours on it now.

I found both props to be equally tolerant of rain, and I have flown in a lot of rain; virtually no wear on the propeller blades but the labels to take a beating.

Performance wise, they both have almost identical climb and cruise performance but the wider blade of the Hartzell does give more braking, which I find useful in competition aerobatics.

Hope this helps you determine which to buy. Let us know what you decide.
 
A friend of mine went from a Hartzell to a WW on his Lancair 360. He's had to send it back to WW 4 times for grease leaking out of it. They gave him some accuses but none made sense.
 
I'm sure the WW is a good prop and the company will stand behind it. However, there are too many unanswered questions and concerns about the WW for my taste.

I know the Hartzell is a great prop. The reliability and durability are well proven. The fact that it is a certified prop gives me an assurance it has been well tested and the QC during manufacture is well documented.

Hartzell composite it is.

Thanks for the advice and the information.

Now to figure out what cowling to use with the Superior cold air sump...
 
Whirl Wind Avaition - HRT Propeller

I just wanted to post an update on our latest HRT propeller blade style, as well as answer some questions.

This year (2017) WhirlWind has released a new RV constant-speed propeller option, called the HRT74-200 Series. This is a constant-speed, 2-blade, 74-in diameter propeller. The HRT propeller was a direct result of our involvement over the last several years in working on a special propeller development program for the Reno Sport Class Racing. We developed new aero-design / structures, manufacturing and testing methods to meet the challenges of taking propeller design to a new level.

The new HRT propeller has shown performance increases across the entire flight spectrum compared to the already great performing 200RV propeller. The most significant improvements have been in take-off acceleration and initial rate-of-climb, there is also a modest top-speed increase.

The HRT hub system is the same as 200RV (based on the McCauley threadless design).

The HRT blade construction however, is all new. The HRT blade uses prepreg carbon-fiber with high-density foam-core that is compression molded in a 50-ton heat press using our proven patented design and manufacturing process. With this new structure design, the HRT blade can be manufactured with a very thin cross-section, and in most cases will be much thinner than a metal blade. Thin blade cross-section is one of several important criteria for an efficient propeller design, which gives the HRT blade an advantage.

Regarding grease leaks on older propellers, we have found that even with our proven hydraulic control hub system (McCauley based), grease leaks are more of a challenge for lighter composite blades than heavier metal blades. There were only a few occurrences of leaks, but testing of a new seal system seems to have solved the most challenging of these issues.

Below are pictures of the HRT blade design undergoing (strain-gauge) vibration survey testing, as well as cross-section of the HRT blade. *Notice the VERY thin HRT cross-section.

After several year of development, this entire HRT project was intense, and at times challenging, but definitely rewarding. The story of the this HRT project and engineering would make a good book someday.

The HRT constant-speed propeller is sold through our constant-speed propeller division, Whirl Wind Aviation http://www.whirlwindaviation.com


DSCF6058-M.jpg


and

DSCF6258-S.jpg
 
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I recognize you are a small company and don't have the resources of Hartzell and some of the others.

That being said, it would have been very helpful to staff your booth with someone with a strong technical background. The gentleman that was there on the day I visited (Wednesday) knew pricing and that was about it. He was unable to provide any detail on blade construction on the various models.

If you could provide more information on the hub, that too would be helpful. "Based on McCauley" does not say much about the metallurgy, machining, QC and testing and how that compares to the certified hub yours are based on.
 
Very similar

No doubt the WW will be a good prop.

I'm personally a little more comfortable with a certified prop for my application. Yes, I know it's an "experimental airplane" and an "experimental engine" (using PMA'd parts and completely inspected by Penn-Yan), but for me the Hartzell is the right choice.
 
HA blades upgrade

,HI all, my prop shop GT-Propellers is an EASA certified prop company for design and production of fixed pitch and CS propellers.
Most of us here in the shop are pilots and homebuilders so we got a deep love for experimental aircrafts .Just purchased a RV4 with some friends !
Up to now we have converted about 386 stock Hartzell cs propellers removing metal blades to evergreen wood/composite technology !
2,3 anf 5 bladed from 150 to 500 HP,several blades models are possible.
The most demanded by Rvers are the two blade 72/ and 74 with nickel leading guard. Weight loss is about 18/20 pounds. depends blades models.
All our blades follow rigid standard EASA and root safety factors is impressive. This is very safe and quick conversion Several US propellers shop has already installed our blades directly troublefree.
Just a recent comment from US operator installed on the Falco. http://www.seqair.com/Hangar/Letti/GTPropeller/GTProp.html


To learn more, please feel free to reach me directly or our canadian support.

info@gt-propellers
[email protected]
More prop variety GT here :
https://www.facebook.com/GtProp/
https://www.facebook.com/yakpropellerexpert/

All the best.
Alex Tonini
 
The other side

I think we are all in agreement that both of these composite wide blades are great performers......my question is this.. What effect do they have on glide distance with an engine out scenario? It has been mentioned that they are great for braking....would this also equate to a detrimental glide ratio after engine failure?

Just curious here
 
price

No price listed. Need to get the price posted or listed on the website. Some of us like me, like to compare what is on the market to sell at this point in time and not speculate on what will be available in the future.

Just bought one of the 74HRT's at SNF....9,215 plus shipping!
SNF had a 5% discount for 8,754.
Includes custom PPG paint colors on blade and tips plus a primed spinner assembly.
 
Comparison

Just bought one of the 74HRT's at SNF....9,215 plus shipping!
SNF had a 5% discount for 8,754.
Includes custom PPG paint colors on blade and tips plus a primed spinner assembly.

Hi Bob can you give ups any performance figures, and are you replacing and old prop you can compare with, or is it a new fit?
 
not yet

Hi Bob can you give ups any performance figures, and are you replacing and old prop you can compare with, or is it a new fit?

We have not received the new WW prop yet. They said eight weeks lead time and it is just now eight weeks so it should be very soon.
Yes we are replacing a Hartzell paddle prop, HC-C2YK-1BF
We are planning some test flights before removing to compare the difference between the two, yes!

And once we are happy with the new WW 74HRT install, the Hartzell prop will be for sale.
HC-C2YK-1BF SN:CH33447B BLADE DESIGN F666A-4
This is the older standard Vans CS prop with the paddle blades before the Blended tips came out.
 
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WW

What is the tear down spec for the HRT prop?

Carl
From 74 HRT online Manual:

7.1 Teardown Inspection Schedule
Refer to the original propeller data sheet for recommended
teardown inspection schedule. If the original data sheet
cannot be found please contact Whirl Wind Aviation directly
to confirm the recommend schedule for your propeller.

Carl,
I assume we will get more current info "with" the propeller.
I am also assuming it will be similar to previous WW models.
 
Just curious. Listed WW prop tear down inspections vary; 250 hours or 1 year, 350 hours or five years, 650 hours or 5 years, etc.

Point being, maintenance requirements are part of the decision tree.

Carl
 
Just curious. Listed WW prop tear down inspections vary; 250 hours or 1 year, 350 hours or five years, 650 hours or 5 years, etc.

Point being, maintenance requirements are part of the decision tree.

Carl

Yes Carl, the maintenance requirements tips the ownership cost toward the more expensive up front cost Hartzell to have the lower life cycle cost. Several posts above back that up. Now if Whirlwind used the Hartzell hub instead of the McCully hub we may then have similar life cycle costs.
 
WW Stories

I've had two Hartzells and two WW. I won't go into it here, but PM me and I will tell you about my experiences with WW and why I am a Catto flyer now.
 
Decision made

Sent the form to Van's this morning for the Hartzell composite with the extended M hub. Big bucks but should be a great prop on our RV-7A.

Thanks for all the advice and experiences.
 
Interested in this too.

I've had two Hartzells and two WW. I won't go into it here, but PM me and I will tell you about my experiences with WW and why I am a Catto flyer now.

I will be buying a new prop, I would be interested in your experience too.
 
Hartzell v Whirlwind

Bob, I'm excited to hear the comparison of the BA vs newer WW. I'll definitely keep an eye on this thread as it progresses. I've heard the BA wins performance wise vs the older 200RV on the same aircraft.

My $0.02... My -7 with the Hartzell BA is perfectly balanced. It's almost impossible to load it out of CG. The plane is off the runway in a couple hundred feet and climbs like a beast. Plus, there are no aerobatic limits (no extension req'd) and no RPM limits with this combo. So, I'm very very happy.

However, I flew through some decent rain last weekend and noticed some of the paint had eroded very slightly. I hear the nickel leading edge on a composite prop is better for rain and backcountry flying. Anyone with experience there? How is the W&B with a lighter prop?

I also flew a -7 with a 3 blade composite MT prop which was a super smooth running combo -- almost turbine like.
 
update

Just an Update as I know a few are watching the thread.
We have still not received the new 74HRT from WW.
15 weeks now.......and still no shipping notice.
WW says they are very busy.
 
HRT

For what it's worth, I have the HRT on order also. I've been told it will be shipping this week. No tracking info yet.
 
Prop

No Whirlwind prop yet.
Last email said hopefully.....the end of this month.
They said still had others in front of us.
Ordered at SNF.
This week will be 20 weeks.
Paid deposit with order.
Have not been asked for balance.
No shipping info.
Invoice date 4-13-17
Order # 3263
WW has been responsive to my emails and just keep pushing the completion date out, email by email. Explainations of just being overwelmed by orders and repairs etc. 8 weeks, 10 weeks, 12 weeks, few more weeks, end of the month...
Not a problem for us as we are still happily flying the Hartzel prop. It does make us wonder about what happens, once we install the WW and sell the Hartzel, if we have a problem with the prop and have to wait and not fly.:eek:
To be clear......I am not vendor bashing, just stating the facts so others in the same position or curious can be in the loop.
Upperdeck.....thanks for posting your info...somehow it helps.
 
Bob I am a day and 2 invoice numbers ahead of you and I have not heard anything about shipping from them yet. I'm in no hurry though either.
 
New WW Prop

I thought the new WW was for 195hp or above aircraft--is that incorrect?
Got that from WW over the phone.

db
 
I thought the new WW was for 195hp or above aircraft--is that incorrect?
Got that from WW over the phone.

db

I was told the same thing, my engine is 210 hp on Titans dyno.

I'll post up any new info on delivery. For what it's worth, I placed my order at OshKosh in 2016 but deliberately delayed delivery.
 
Do you guys have any details or photos of this new prop? I can't find anything about it on their website.
 
195?

From their PDF manual on the HRT74.
2.1 Description
Performance & Quality. This 74HRT Series propeller has
been designed to maximize the performance of your
airplane. This propeller delivers exceptional performance for
the modern day sport aircraft. The exceptional performance
is derived from advanced engineering developments,
including the use of our latest airfoils.
- The 74HRT Series is a two-blade hydraulic constant
speed propeller system designed for aircraft using the
Lycoming O/IO-320, -360, -375 & -390 engines (150 -
220 hp).

EDIT: UPdated info from Bill Koleno at WW......above info is / was a typo....and is being corrected now.
 
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HRT74 Prop

Thanks for that Bob. The text is very informative and unambiguous. Wonder why they told at least two of us otherwise?? Think I will give them a call.

Cheers,
db
 
Thanks for that Bob. The text is very informative and unambiguous. Wonder why they told at least two of us otherwise?? Think I will give them a call.

Cheers,
db

We had to read between the lines on this very issue before purchasing. We were at SNF talking to Chaz and touching the blade displays.

See Post 17 of this thread from WW...cutting section from post:
The new HRT propeller has shown performance increases across the entire flight spectrum compared to the already great performing 200RV propeller. The most significant improvements have been in take-off acceleration and initial rate-of-climb, there is also a modest top-speed increase.

Thinking the NEW HRT74 is replacing the previous bigger bladed prop that was clearly marked for higher HP. Yet the above comments from WW say the 74HRT outperforms the 200WW. And their documentation in the manual says it can be used down to 150HP. So we are thinking the 2017 design is just that, NEW.......and we are taking a chance.

FYI...when I say we, I am speaking of my hangar mate and I. Each with RV-6's and 0-360 A1A's...but his 0-360 has 9.1 pistions and Lycon flowed cylinders and clearly has more more than my stock 180. (but not dyno'd). I plan to install on both planes to compare performance. Hopefully the new blade design will or is cutting edge and be a winner.....Time will tell.
 
HRT Prop

Hey Guys,

Late yesterday I talked with Bill K. of Whirlwind. He is involved with the testing of their propellers including the HRT74. Bill tells me that the new HRT74 prop is designed for 205 hp or above. He suggested that if you have an HRT74 ordered and do not meet this minimum hp you should give Whirlwind a call.

Thought you folks needed to find this out now.

Cheers,

db
 
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