201 MT Propeller vs 3-Blade Macauley "Blackmac"

[1001001]

Title says most of it.  My '78 201 currently has a 3-blade Macauley "Blackmac" propeller on it that was installed a long time before I bought the airplane.  From what I can tell, this prop weighs over 71 lb on the nose.  The airplane climbs very well, but I have never been able to get book cruise numbers at any altitude with it.  I have to carry about 50lb of ballast in the baggage compartment to keep from running out of nose-up trim when landing the airplane when solo.

I'm considering replacing the Macauley with an MTV-12-B/180-59b propeller.  I've read the various threads I could find here on the MT propellers, and the consensus seems to be it is a better option over 2-blade propellers, or at least a wash.  

I'm interested in other people's experience with the 3-blade Macauley, and especially anyone who's changed it out for an MT-12.  What were your performance numbers for the 3-blade Mac versus 2-blade, or vs the 3-blade MT?

 

 

[A64Pilot]

It’s my understanding that as far as cruise speed, nothing outperforms the stock two blade Mac that came on the 201.

That’s second had info, I’ve not tested multiple props on my airplane.

From my experience with other aircraft the primary advantage of three blade props is appearance 

However and I’ll get arguments on this but few aircraft actually achieve “book” performance.

[1001001]

6 minutes ago, A64Pilot said:

It’s my understanding that as far as cruise speed, nothing outperforms the stock two blade Mac that came on the 201.

That’s second had info, I’ve not tested multiple props on my airplane.

 

That is the conventional wisdom, but there are multiple posts on this forum and other places that seem to contradict the OWT that a 3 blade prop is necessarily slower in cruise than a 2-blade.

Edit:
For instance: 

In any case, thanks for contributing!  I'd like to hear others' experiences with both the Macauley 3 blade and the MT 3 blade.
 

Edited March 29 by 1001001

[Aerodon]

Can you install 'Charlie Weights' in the tail of a 201 or is it a 231 thing?  11 lbs in the tail is a lot better than 50 lbs of unnecessary baggage.

I went with a new 2 blade prop instead of any of the 3 bladed options.  

My opinion, MT's are very nice but I don't like their service interval and repair an overhaul price. And overhaul locations.  I think you are just setting yourself up for much higher future costs with very little performance benefit.

 

Aerodon

 

 

 

 

 

 

 

 

 

[1001001]

16 minutes ago, Aerodon said:

Can you install 'Charlie Weights' in the tail of a 201 or is it a 231 thing?  11 lbs in the tail is a lot better than 50 lbs of unnecessary baggage.

I went with a new 2 blade prop instead of any of the 3 bladed options.  

My opinion, MT's are very nice but I don't like their service interval and repair an overhaul price. And overhaul locations.  I think you are just setting yourself up for much higher future costs with very little performance benefit.

 

Aerodon

 

 

 

 

 

 

 

 

 

I'm thinking I could save 25.3 lb on installed weight for the prop alone, plus remove the 50 lb ballast, for a net increase in useful load of 75 lb.  
I'm told that in both Mooneys and RVs, the MT props are very smooth.  My 3 blade Macauley has a lot of vibration to it (which could be taken out with a good balancing, but it seems the wood-based props are inherently lower in vibration than metal.  

[Aerodon]

Agreed, there may be more of a smoothness benefit on a 4 banger, but I find the 2 blade smooth enough on the TSIO360.  (and I have 3 blades on my seneca, so have compared the two).

And you are doing a biased comparison on the useful load comparison.

Try a W&B with 11lb of charlie weights and your current 3 bladed prop and the benefit is more like 36lbs.  Try it again with a 2bladed prop.

And to be clear, I like the MT props, and generally take whatever little performance and weight reduction I can.  I just don't like their service requirements, cost and logistics.

 

Aerodon

 

 

 

 

 

 

 

 

 

 

 

[1001001]

28 minutes ago, Aerodon said:

 

Try a W&B with 11lb of charlie weights and your current 3 bladed prop and the benefit is more like 36lbs.  Try it again with a 2bladed prop.

 

 

So, Hartzell's 2-blade  (https://hartzellprop.com/products/top-prop/mooney/m20a-g-m20j-2-blade/) weighs 62-64 lb installed.  That's aluminum; I tried to find a composite prop that Hartzell advertises for the Mooney but couldn't.   Maybe my search-fu is weak.

Macauley doesn't list weights for their 2-blade propellers (https://mccauley.txtav.com/en/products?PropType=constant&OEM=MOONEY+AIRPLANE+COMPANY%2c+Inc.&AircraftModel=M20J+201&EngineType=IO-360-A3B6D+(LY)) 

Edited March 29 by 1001001

[KSMooniac]

I replaced my original 2-blade Mac with the skinny chord and square tips ('77 J ) with the MT you're considering, and would choose it again without hesitation.  It was ~12-13 lbs lighter than OEM, smaller diameter/more ground clearance, and DRAMATICALLY smoother.  It is the only prop that offers more ground clearance on a Mooney in case that is important to you.  I expect all of those benefits are far greater when replacing a 3 blade metal prop of either flavor.  I dynamically balanced my installation down to 0.01 IPS and it feels like a sewing machine.

Performance wise, better takeoff, climb, and landing and no loss of cruise speed compared to my original.  The later 2-blade Mac with round tips and fatter chord is faster than my original, though.  I believe the fastest option on the market is the Hartzell Top Prop, but it is heavy and had a lot of spinner/bulkhead/backplate failures in my observation.  Hartzell seems to have a habit of releasing AD's when their sales slow down too.  The newest 2-blade Top Prop with the composite blades is the only option that might tempt me away from the MT, but I don't believe they have an STC yet, and even worse, the new private equity owners have sent prices to the moon so I doubt I will ever buy any of their products in the future.  Norman (@testwest) has some very accurate models of the J with various props and he can give you a far more technical answer than I can.  He chose the original Top Prop for his highly-optimized J and was seeing 165 KTAS at 10 GPH in cruise...fastest J to my knowledge.

There is a lot to like with the MT and I've written extensively about my experience here.  I'm fortunate to have a distributor/service shop local to me, though, to address Don's concern above.

EDIT:  New Top Props Trailblazer - Hartzell Propeller

Switching from Hartzell Blended Airfoil to a Trailblazer Propeller - Glasair Aircraft Owners Association (glasair-owners.com)

This is the future candidate prop, but not approved for us yet... hopefully soon, and at a reasonable price.

[A64Pilot]

2 hours ago, 1001001 said:

That is the conventional wisdom, but there are multiple posts on this forum and other places that seem to contradict the OWT that a 3 blade prop is necessarily slower in cruise than a 2-blade.

Edit:
For instance: 

In any case, thanks for contributing!  I'd like to hear others' experiences with both the Macauley 3 blade and the MT 3 blade.
 

I love how people who don’t like something like to claim it’s some kind of unsubstantiated belief.

However it’s not. I’ve spoken with a few Hartzell Engineers and Joe Brown a couple of times on this subject as well as Igor Brunchelik owner of Avia propellor and Zbynek Tvrdik one of Avia’s Engineers and if all things are equal the fewer the blades the less the drag, so fewer blades are more efficient, being more efficient means greater thrust.

This has been known forever and because of this single blade props have been tried. I can’t seem to find it on the internet but I believe way back Hughes Aircraft even built an Experimental single bladed helicopter to see how much more lifting power it would have. Any perceived increase in efficiency was I believe more than washed out by the problems a single blade caused.

You go to multiple prop blades for many reasons, but primarily it’s because of ground clearance, some other reasons are to enable lower tip speed as when tip speed gets up to roughly .84 Mach its noisy and inefficient. For example the smallest Crop Duster we built had a three blade 106” prop that could turn a 2200 RPM which is about .9 Mach, working with Pratt and Whitney we were allowed to increase engine torque from 58.7 PSI to 64 which still gave us 750 SHP reducing the prop tip speed to .83 Mach which both increased performance and reduced noise significantly.

Multiple blades can reduce noise somewhat and can be slightly smoother, but as there is more surface area there is more drag.

There are other considerations of course, for example when Hartzell undertook designing a new prop for the GE H-80 engine they ended up with a four blade prop, they were trying to exceed the performance of the three blade Avia prop, but the required blade profile to do so exceeded the centripetal force limits of any of their existing hubs so they had to go to a four blade prop.

It’s entirely possible that a three or even four blade prop could outperform a two blade, but it would be because of a superior airfoil, not due the number of blades.

At the air speeds we fly at all things being equal, the fewer the blades the better, unless of course someone builds a three blade with an airfoil that’s efficient enough to overcome the increased drag

 

[KSMooniac]

13 minutes ago, A64Pilot said:

 

It’s entirely possible that a three or even four blade prop could outperform a two blade, but it would be because of a superior airfoil, not due the number of blades.

At the air speeds we fly at all things being equal, the fewer the blades the better.

 

This is true.  If there was a 2-blade MT available in 2010, I would have much preferred that over the 3 blade I bought.  I'm still happy with the 3 blade, though.  I didn't lose any cruise performance b/c it replaced a 70's design with a late 2000's design, and the airfoil and planform are more efficient.  I did get better acceleration and climb, and far greater aerodynamic braking when pulling the throttle because of all the extra blade area.  

Last year at OSH I drooled on the new Trailblazer 2-blade prop as a potentially optimal choice for any 4 cylinder Mooney.  But the new owner's behavior earlier this year likely means I'll never be able to afford it, unfortunately.  We'll see.

[1001001]

36 minutes ago, A64Pilot said:

I love how people who don’t like something like to claim it’s some kind of unsubstantiated belief.

However it’s not. I’ve spoken with a few Hartzell Engineers and Joe Brown a couple of times on this subject as well as Igor Brunchelik owner of Avia propellor and Zbynek Tvrdik one of Avia’s Engineers and if all things are equal the fewer the blades the less the drag, so fewer blades are more efficient, being more efficient means greater thrust.

This has been known forever and because of this single blade props have been tried. I can’t seem to find it on the internet but I believe way back Hughes Aircraft even built an Experimental single bladed helicopter to see how much more lifting power it would have. Any perceived increase in efficiency was I believe more than washed out by the problems a single blade caused.

You go to multiple prop blades for many reasons, but primarily it’s because of ground clearance, some other reasons are to enable lower tip speed as when tip speed gets up to roughly .84 Mach its noisy and inefficient. For example the smallest Crop Duster we built had a three blade 106” prop that could turn a 2200 RPM which is about .9 Mach, working with Pratt and Whitney we were allowed to increase engine torque from 58.7 PSI to 64 which still gave us 750 SHP reducing the prop tip speed to .83 Mach which both increased performance and reduced noise significantly.

Multiple blades can reduce noise somewhat and can be slightly smoother, but as there is more surface area there is more drag.

There are other considerations of course, for example when Hartzell undertook designing a new prop for the GE H-80 engine they ended up with a four blade prop, they were trying to exceed the performance of the three blade Avia prop, but the required blade profile to do so exceeded the centripetal force limits of any of their existing hubs so they had to go to a four blade prop.

It’s entirely possible that a three or even four blade prop could outperform a two blade, but it would be because of a superior airfoil, not due the number of blades.

At the air speeds we fly at all things being equal, the fewer the blades the better, unless of course someone builds a three blade with an airfoil that’s efficient enough to overcome the increased drag

 

I'm not saying in general that the conventional wisdom is wrong in all cases, only that there exist multiple credible sources of information that refute the generalization that 3-blade propellers must have lower cruise performance than two blade propellers.  

On this very site there are threads with people giving their observations of performance with the same airplane with different propellers.  One thread links to a thread over at Van's Airforce, where a poster gives the results of his comparison of 3 or 4 different propellers on the same airframe, corrected to standard atmospheric conditions.
The  original owner of the engine for my RV-10 did a side-by-side comparison on his own RV-10 of 3 different propellers in the span of one or two days and observed that for the MT and Whirlwind propellers, they both had nearly identical cruise performance to an original two-blade Hartzell.

Again, I'm not trying to pooh-pooh real world data, I'm trying to base a decision on it.  I'm fairly certain that my old Blackmac 3-blade is a dog in cruise compared to the original 2-blade that was on my Mooney.  Not sure why, back in the sands of time, an earlier owner chose to change to it, other than perhaps climb performance or looks.

[DCarlton]

No one has mentioned a cost comparison.  Does your preferred option offer enough of a performance improvement to justify the cost difference?  Does it move the needle?  Now if you just like the looks...  I think in my case years ago, the McCauley three blade was the cheapest and at the time I thought it looked the best...  decision made.  

[philiplane]

The MT prop is lighter because it's got wood blades inside a fiberglass wrap, with some metal glued on to keep it from self-destructing in short order. The fiberglass covers come unglued at the trailing edge. The filler between the leading edge and the blade comes off in small chunks, because those light weight blades flex a LOT.

The hub is lighter because it has no bosses for grease fittings. And the way these props ooze grease, you need to take it off to have a shop re-grease and re-seal after awhile. Which means you're committed to a 5-6 year reseal at a cost of $2k. Provided they don't find any damage from the lack of grease. 

An MT prop will easily cost more per hour than any other prop. I've got another one laying on my hangar floor, going in the dumpster. It's less than 15 years old, less than 3 years since last overhaul, commercially operated and maintained, and was going in for yet another blade replacement, and a re-seal. MT says the internals of the hub are beyond economic repair. Probably since it leaks grease and you can't grease it?

The best prop for a 180 to 270 HP engine, bar none, is the 2 blade Hartzell composite. Second best is a 2 blade Hartzell scimitar. If they make one for your Mooney, get one. 

[201Mooniac]

1 hour ago, philiplane said:

The MT prop is lighter because it's got wood blades inside a fiberglass wrap, with some metal glued on to keep it from self-destructing in short order. The fiberglass covers come unglued at the trailing edge. The filler between the leading edge and the blade comes off in small chunks, because those light weight blades flex a LOT.

The hub is lighter because it has no bosses for grease fittings. And the way these props ooze grease, you need to take it off to have a shop re-grease and re-seal after awhile. Which means you're committed to a 5-6 year reseal at a cost of $2k. Provided they don't find any damage from the lack of grease. 

An MT prop will easily cost more per hour than any other prop. I've got another one laying on my hangar floor, going in the dumpster. It's less than 15 years old, less than 3 years since last overhaul, commercially operated and maintained, and was going in for yet another blade replacement, and a re-seal. MT says the internals of the hub are beyond economic repair. Probably since it leaks grease and you can't grease it?

The best prop for a 180 to 270 HP engine, bar none, is the 2 blade Hartzell composite. Second best is a 2 blade Hartzell scimitar. If they make one for your Mooney, get one. 

That may be your experience but it is entirely different from mine.  The MT 3 Blade prop on my M20J has been flawless for the many years I've owned it.  Nothing coming off in chunks or self destructing and no grease  or reseal needed.  GThe prop has performed exactly as advertised and I would buy one it again.  Given that the blades of my Mac 2 blade prop eroded in just a few years to be unserviceable, I'm very happy with my MT prop.

[gacoon]

10 hours ago, A64Pilot said:

It’s my understanding that as far as cruise speed, nothing outperforms the stock two blade Mac that came on the 201.

That’s second had info, I’ve not tested multiple props on my airplane.

From my experience with other aircraft the primary advantage of three blade props is appearance 

However and I’ll get arguments on this but few aircraft actually achieve “book” performance.

+1

[philiplane]

12 hours ago, 201Mooniac said:

That may be your experience but it is entirely different from mine.  The MT 3 Blade prop on my M20J has been flawless for the many years I've owned it.  Nothing coming off in chunks or self destructing and no grease  or reseal needed.  GThe prop has performed exactly as advertised and I would buy one it again.  Given that the blades of my Mac 2 blade prop eroded in just a few years to be unserviceable, I'm very happy with my MT prop.

It's my experience with more than a dozen MT propellers, several of which the owners have scrapped, and gone back to Hartzell.

We're about to do that to another one that is seven years old with only 850 hours since new, has been resealed three times, continues to leak, and the deice boots are also falling apart. On a hangared, well-kept airplane. 

I think the folks who have good luck with the MT don't fly very much. On flight school planes, the MT needs work every 100 hours. Paint, filler, re-gluing the fiberglass every six weeks gets old. I've got a 2023 DA40 with 350 hours and the MT prop is looking like crap already and starting to leak.

On the Cirrus forum, there is a shop gathering data on dozens of case cracks on IO-550's equipped with lightweight props. 

And you might notice the sharp stop and clunking when you shut down your MT-prop equipped engine. What is that doing to the crank counterweights, magnetos, and gears over time? 

[Fritz1]

Noise abatement is the primary cause of existence for the MT prop, if the there is no noise problem other props work just fine, then prop noise is the sound of freedom

[Pinecone]

22 hours ago, 1001001 said:

So, Hartzell's 2-blade  (https://hartzellprop.com/products/top-prop/mooney/m20a-g-m20j-2-blade/) weighs 62-64 lb installed.  That's aluminum; I tried to find a composite prop that Hartzell advertises for the Mooney but couldn't.   Maybe my search-fu is weak.

They are "working on it."  And have been for a while.  This would be for a 3 blade composite.

[201Mooniac]

8 hours ago, philiplane said:

It's my experience with more than a dozen MT propellers, several of which the owners have scrapped, and gone back to Hartzell.

We're about to do that to another one that is seven years old with only 850 hours since new, has been resealed three times, continues to leak, and the deice boots are also falling apart. On a hangared, well-kept airplane. 

I think the folks who have good luck with the MT don't fly very much. On flight school planes, the MT needs work every 100 hours. Paint, filler, re-gluing the fiberglass every six weeks gets old. I've got a 2023 DA40 with 350 hours and the MT prop is looking like crap already and starting to leak.

On the Cirrus forum, there is a shop gathering data on dozens of case cracks on IO-550's equipped with lightweight props. 

And you might notice the sharp stop and clunking when you shut down your MT-prop equipped engine. What is that doing to the crank counterweights, magnetos, and gears over time? 

I don't dispute your experience but again, in my experience I've flown 150 hours a year for the past 5 years on this prop with no issues at all.  Maybe there is some difference with the way they are operated or some other factor that is currently unknown but I wouldn't want someone to only consider one experience when making a determination.

[MikeOH]

1 hour ago, 201Mooniac said:

I don't dispute your experience but again, in my experience I've flown 150 hours a year for the past 5 years on this prop with no issues at all.  Maybe there is some difference with the way they are operated or some other factor that is currently unknown but I wouldn't want someone to only consider one experience when making a determination.

Glad to hear you've had a, i.e. one, good experience...I believe Philiplane's experience was with "more than a DOZEN MT propellers."

So, when it comes time for a new prop, I'm going to consider the more than one experience and stick with the 2 blade all-metal Hartzell

[1001001]

I appreciate people sharing their experiences and observations.  I don't wish to be rude, but can anyone answer my original question, which was about a direct comparison in performance between the 3-blade "Blackmac" and the MTV-12 propellers?

[DCarlton]

3 hours ago, 1001001 said:

I appreciate people sharing their experiences and observations.  I don't wish to be rude, but can anyone answer my original question, which was about a direct comparison in performance between the 3-blade "Blackmac" and the MTV-12 propellers?

This prop comparison topic seems to come up over and over again and I don't think I've ever seen an engineering or test report with any actual data.  That would be interesting.  I'd like to see the two blade Hartzell vs three blade McCauley comparison with data.  I would prefer climb performance over a few knots extra speed as long as it's still as smooth.  

[Larry]

Not to side-track this discussion; What is a used McCauley worth?  I have a +/- 4000 hr McCauley 214 off of a '90 201 always hangared.  Stallings did an IRAN 450 hours ago.

Now back to our previous discussion.

[N177MC]

On 3/31/2024 at 8:15 PM, Larry said:

Not to side-track this discussion; What is a used McCauley worth?  I have a +/- 4000 hr McCauley 214 off of a '90 201 always hangared.  Stallings did an IRAN 450 hours ago.

Now back to our previous discussion.

PM sent .

[Will.iam]

On 3/31/2024 at 7:50 AM, 1001001 said:

I appreciate people sharing their experiences and observations.  I don't wish to be rude, but can anyone answer my original question, which was about a direct comparison in performance between the 3-blade "Blackmac" and the MTV-12 propellers?

No one has directly answered your question because nobody had a 3-blade blackmac and went to the MTV-12 propeller or if they did they did not post their results here with before and after test.  You are the first, please post your results here after you do the switch so you can help other people out when they face that same decision, although with the factory not putting on a 3-blade blackmac I doubt there is very many other pilots in your shoes. Maybe ask the bonanza forum to see if they have had someone make this very switch before.