C-180: MT vs Mac 401 Props

I happened to be on the plane home from the Airmen's show with one of the MT Prop reps. Their booth is always right down from ours, and of course, I have an MT on my cub so we have chatted a lot about props, etc. His pitch was that by going to a 2 Blade MT on my C-180 (MT holds the STC to put it on a PPonk engine, not Knopp) instead of the Mac 401 I currently have, my life will be blessed with faster cruise, better climb, and of course, lighter weight on the nose. I would guess it might involve a little more vibration.

Anybody got an MT on a PPonk? Especially anybody who has made the 401 - MT switch, I'd live to hear your comments. Of course, rampant speculation is always welcome too

Now, I know there are a lot of you folks that don't like those wood and plastic props, but I am perfectly happy with the one on my cub, so the part of it "not being metal" does not really bother me.

I just think there HAS to be a tradeoff....

sj

SJ,

From the research I've done I'm really interested, and the other benefit they claim is greatly reduced noise. Right now I'm in the fund raising portion of the project, I was putting away a bit each month but lately I have a new strategy, I just leave really early with the prop full-in and I didn't back it out until I'm just past Eaton's! Linda says the check's in the mail!!

Kirby

Steve, not sure if your computer will even acknowledge posts on BCP :lol:, but there is a lot of good info over there on this subject. Aktahoe bought both the Mac and the MT to do a comparison on his pponked 180. Rob has an MT on his ponked 180 and there are probably others.

Thanks! I'll have a look. Specifically looking at the 2 blade vs 3.

sj

I can only speak to my experience with them. But aircraft / powerplant wise we are very close

I believe you will find that the trade off is that the 2 blade MT is not enough prop to make use of the power produced by a healthy Pponk. It certainly wasn't enough prop for mine. Yes it will work, but unless all that matters for you is CG (as in on an amphib) it's probably not going to be your optimum choice.

If I were a betting man, I'd bet your airplane is on the fwd edge of the CG envelope. Putting a 2 blade MT on there is going to make it handle better than your cub... Honestly... But it's going to run out of poop when you pour the coals to it... Coming from a 401 you will be disappointed in that single regard. But it will be a big disappointment .

The 3 blade MT will do almost everything a 86" 401 will do and then some (you didn't say how long yours was) and it weighs almost the same as a C66 Mac 2 blade. So quite a bit less than your 401.
For my purposes this is the best compromise. It is by no means perfect, and there are a couple gotchas, that can be ugly if you let them. But I guess that can be said of any prop... Feel free to pm me if you want specifics on my perceived MT uglies. I like the prop, and the dealer, so don't really want to be part of a flame war...

My experience comparing the two 3 blades is that the 401 can provide just a scosh more thrust with the tail tied down or a full brake locked take off from pavement, but in the real world of throttle handling the MT beats it off the ground because once your rolling it spools up so much faster. It is a faster prop than a long Mac, but I couldn't speak to a short 401. These two are close enough that choosing the right one has a lot more to do with your specific needs / mission than anything else...

If it matters to you, the TBO on the 3 blade MT is longer than the 2. I don't care about the specific numbers, but the simple concept suggested something about longevity to me. And that I do care about.

Take care, Rob

i don't know about a c-180 but we put the 5 blade MT's on our metro's, now they start 15sec faster the noise is wway down! along with the vibration we were getting from the 4 blade mac's. we also did one of the cheapest O/H on our engines running the MT's. i think they will save us lots of $. the only issue we have is the reverse is alot more effective and we do have to keep repainting the front of the prop. I have been trying to talk my father into putting an MT on his 180, plus reverse would be nice for him(or is that not an option on the 180?) I am a fan of the wood/comp props I also put the catto's on my cubs.as any time you can get rid of alot of vibration it will prolong the life of your engine and airframe.

Thanks Rob, et al,

The 401 is smooth as glass. The weight on the front does not bother me at all and I only notice it when I fly a plane that does not have so much up front. It is noisy (86"), and I dial it back really quick.

Guess I will stick with the horse I have and the grass on this side of the fence...

sj

SJ said:

I happened to be on the plane home from the Airmen's show with one of the MT Prop reps. Their booth is always right down from ours, and of course, I have an MT on my cub so we have chatted a lot about props, etc. His pitch was that by going to a 2 Blade MT on my C-180 (MT holds the STC to put it on a PPonk engine, not Knopp) instead of the Mac 401 I currently have, my life will be blessed with faster cruise, better climb, and of course, lighter weight on the nose. I would guess it might involve a little more vibration.

Anybody got an MT on a PPonk? Especially anybody who has made the 401 - MT switch, I'd live to hear your comments. Of course, rampant speculation is always welcome too

Now, I know there are a lot of you folks that don't like those wood and plastic props, but I am perfectly happy with the one on my cub, so the part of it "not being metal" does not really bother me.

I just think there HAS to be a tradeoff....

sj

Click to expand...

Tradeoff? Removal of weight from both your wallet and nose

SJ, I made the exact switch you are asking about 3 years ago. Removed the 3 blade 401 mac from my Pponked 182P on floats and replaced it with the 2 blade MT. There is no downside other than cost. Don't have my log books, but as I recall the weight savings was 30+ pounds, it pulls harder, is faster, climbs better, is quieter, spools up and down much faster, and it is smoother than the 3 blade. If you think your 3 blade is silky smooth you wont believe the difference to the 2 blade MT, but try it and you will agree. The weight savings on the nose of the plane makes it fly like a completely different bird. I was debating going to the 2 or 3 blade MT, when a used 2 blade MT came along that someone had driven into a dock and busted it up. It was completely rebuilt with new blades at the factory and I bought it for $8000 as I recall. If I was buying new, I would go with the 3 blade. The ponk has the power to wheel the 3 blade just fine. The other poster that mentioned the thread on BCP.org is correct. Aktahoe had brand new ponk on his 180 and started with the 3 blade mac on it, after couple weeks tried the 3 blade MT. His testing showed there is no comparison between the 2 props. He had the brand new Mac on and liked it. MT offered to let him try their 3 blade MT and return it if he wasn't impressed. He sold the Mac. The MT outperformed it in every aspect. I've never heard of an MT owner swithing back to metal. If you search the BCP site, you will see some of the postings I had on my changeover to the MT. My handle is Rhyppa over there. Russ

Interesting contrasting results here. I have an opportunity to "test" one so I might have to do that.

The person I spoke with said the two blade was the right prop, would the three blade be better in this instance?

sj

If I needed an XC machine that was faster and climbed better and off airport damage wasn't a concern? I'd buy a Bonanza.

If speed is the goal there are other ways to achieve it. http://sniderspeedkit.com

I would too, Stewart. I'm not concerned about off airport damage on the MT's because I think the hundreds of hours I have banging around in the one on the cub has proven to me that it is a very robust prop, not because I am not using it off airport.

Bonanzaman from Montana can do in a Bonanza what a lot of people wish they could do in their cubs! It's a tough airplane to boot.

sj

Sounds like your mind's made up. Give us a pirep after you've flown it awhile.

Good thing you didn't sit next to a Socata rep on that flight!

HA! I can't really afford to switch, but will try it out if I have a chance. (The MT, not the Socata).

sj

Speed was not the issue in my case, nor seldom is with a floatplane. On my 182P on Aerocet 3500 straight floats, it would run out of nose up trim when landing without significant weight in the back. I was hoping to get equal thrust with less weight and the 2 blade MT did just that and better. I think the 3 blade MT is still 20 pounds or so lighter, with even more out of the hole pull than the mac. Like I said, if I were buying new I would go with the 3 blade, but the 1/2 price deal I got on the 2 blade was too good to pass up. The stainless edge on the MT handles the water spray much better than the aluminum mac, and after 3 float seasons the prop still looks like new. A number of people have had the opportunity to try one for free and return it at no cost through Larry or John at Flight Resources in Chatek WI. If you can't afford it don't try it cause you won't be taking it off.

SJ said:

Bonanzaman from Montana can do in a Bonanza what a lot of people wish they could do in their cubs! It's a tough airplane to boot.

sj

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I'd sure agree with that comment. He takes his Bonanza into the rougher Breaks strips where some guys think they need 31" Bushwheels. A couple of years ago he got it down and stopped in half the distance the guys in 180's where using at Ryan's. I had my PA18 there that year and watched him get stopped nearly as short as I did. Scott is president of the Montana Pilot's Assoc. this year now too.

I am still bitter of flying 14 hours from Ohio and landing at dusk for our SC.Org back country soiree in Cow Creek to fall out of the SC to find my back country strip had a Bonanza parked there......WTF!

I'll wash the coffee off of the computer screen now.....

SJ said:

Interesting contrasting results here. I have an opportunity to "test" one so I might have to do that.

The person I spoke with said the two blade was the right prop, would the three blade be better in this instance?

sj

Click to expand...

Actually my experience has been that contrasting reports are the rule of the day when it comes to props :lol:
FWIW, if I were on floats (specially amphibs) like supechamp, I would probably do the two blade as well... They are both really good choices, only you can say which one will fit you best. Russ how long was your 401?

I have one other interesting observation as well.. Contrary to popular belief we have found that running a 401 faster than the recommended T/O rpm continues to provide an increase in thrust, albeit at a pretty sharp noise penalty...
The MT in contrast seems to excel a bit more with the prop turned a scoch back on T/O...


Take care, Rob

sierra bravo said:

If I needed an XC machine that was faster and climbed better and off airport damage wasn't a concern? I'd buy a Bonanza.

Click to expand...

Yea, but no one drools over a "Bo" at the fuel pump!

Steve,

You should check in w/ aktahoe1 over on backcountrypilot.org for info on the MT prop on a 180:

http://www.backcountrypilot.org/forum/viewtopic.php?f=34&t=11025

OLDCROWE said:

Yea, but no one drools over a "Bo" at the fuel pump!

Click to expand...

I do. I'd love to have a good A36,but it doesn't fit my Alaskan mission profile very well. Great airplane.

Rob said:

The MT in contrast seems to excel a bit more with the prop turned a scoch back on T/O...

Click to expand...

Have to do this on the cub as well.

sj

I could not be happier with my MT! No experience with the 2 blade but everyone from Knopp, Neilson, Mandes and others recommended the 3 blade. The pull tests between the 86"401 Mac and the big 3 blade MT where not even close. Losing the 30lb dumbbell on the nose was also a big factor for me. The girl flies like a cub...(well almost). The spool up is quick and very responsive. My biggest concern was the ability to take abuse. I can tell you now with almost 170 hours on the prop and 500 landings in the sticks, including some serious sage brush mowing, the MT still appears to be brand new. On skis it was a dream. I always hear about how expensive the MT is over the Mac. The extra $3500 is worth it's weight in gold.

AKT

With out MT, I would simply be losing HP, destroying CG (amphibian, skis), and buying lots of fine tooth files.

ACA Scout w/ O360

8GCBC said:

With out MT, I would simply be losing HP, destroying CG (amphibian, skis), and buying lots of fine tooth files.

ACA Scout w/ O360

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Can you please clairify some comments for me?

I am trying to understand the contradictionary things I've heard about this prop, I value the imput from those that use one.

"buying lots of fine tooth files" are you saying you don't need to file out rock knicks? and why?

I sounds like it is tougher than a Mac from what I'm reading.

Ruffair said:

Can you please clairify some comments for me?

I am trying to understand the contradictionary things I've heard about this prop, I value the imput from those that use one.

"buying lots of fine tooth files" are you saying you don't need to file out rock knicks? and why?

I sounds like it is tougher than a Mac from what I'm reading.

Click to expand...

Tougher is very subjective.
It takes water erosion better than a Mac because it has a stainless leading edge.
The bigger ones have nickel, I wish they offered these for the 180
It is a better prop for small rocks and stones because you just epoxy patch the dent, and return the original profile.
It will not take a boulder or stump like a Mac.. But who wants to hit one of those with either... If you do experience a sudden stoppage event that shatters the blade, it will probably be a better outcome for your engine than a metal prop.
It will also not take sharp rocks like shale well either, because these will peirce the leading edge,
there are criteria to these peircings, and the wrong kind leads to LE replacement.

If you live somewhere extremely arid there are other considerations as well...

They all have merits, and they all have faults

Take care, Rob

I have tried the 2 blade MT on my P-Ponk 180 with 8.5to1 pistons and was not satisfied with the performance. I have a Hartzell 3 blade 84" semitar and very happy with it. Turbine smooth and pulls very well. I felt the 2 blade did not pull as hard or get off the ground as quick as the Hartzell and slower cruise.
Would like to try the 3 blade MT sometime.

Speaking of tractors......

.........HAs anyone devised a method to test thrust in a DYNAMIC way rather than the static method?

Some airfoil sections of props are great performers static, others work better as they move through the air.

MT has everyone else beat on the weight, no argument.

Radar guns and other speed trap equipment are pretty common these days. It seems like a well conducted acceleration test would tell that tale. It'd need to use the same plane in the same conditions. Not easy to do but not impossible, either. Of course it would probably be done on a clean, paved surface. Move it to a gravel or scree strip and results might be different since the operator isn't going to just lay the whip to it, depending on the surface and his willingness to sling rocks off the prop.