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Backcountry Pilot • More thoughts on CG: MT's and Big Mac's

More thoughts on CG: MT's and Big Mac's

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More thoughts on CG: MT's and Big Mac's

FWIW... I just installed a 3 blade MT in lieu of an 86" 401 Mac on a customer's bird. The MT pulled 19lbs off the nose and pushed the C.G. rearward 0.78. To prevent any starter adapter whoas, we put new Hartz Energizer back on rather than the ST5, which moved the C.G. back forward 0.13. NET NET, the whole effort moved the C.G. rearward 0.65.

I really do love the MT over the Mac. Yes it pulls ever so slightly less hard, and we did see a tiny reduction in cruise speed (1-2 kts), but man is it so much more responsive and fun to fly... not to mention being neighborly quiet and smooth as a (insert analogy here.) Moving the C.G. .65" is a big help for this bird.
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Re: More thoughts on CG: MT's and Big Mac's

What year and make did you do this on??
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Re: More thoughts on CG: MT's and Big Mac's

I changed from an 86 in 3 blade Mac 401 to a 2 blade MT last year. Plane Power alternator and Hartzell Energizer. The weight off the nose is very noticeable and my 180A just feels and handles much better. Can't remember the exact weight savings and cg change, but it was well worth it. Don't think I lost any cruise speed.
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Re: More thoughts on CG: MT's and Big Mac's

Late model 185.
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote: not to mention being neighborly quiet and smooth as a (insert analogy here.)


You mention quiet. But a lot of other people I've talked to say they are actually louder. I know if a C206 and a 180, same engine on both. 180 has an MT and 206 has a Mac. The 180 is a lot louder...
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote:Late model 185.


That makes sense with that heavy of a plane. It takes quite a bit to move the CG when dealing with a plane that is inherently heavy .
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote: Yes it pulls ever so slightly less hard


Wait, What???

Never heard anyone admit that.

On another note, can you wrap that MT up to 2850 or is it limited to 2700 RPM?
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote:we did see a tiny reduction in cruise speed (1-2 kts)


I'm also shocked to hear this...
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Re: More thoughts on CG: MT's and Big Mac's

Thanks for your candor Greg.

On the subject of Big Mac's I actually prefer the Denali Big Mac. :D

https://www.forbes.com/sites/melissakravitz/2018/05/10/mcdonalds-alaska-denali-mac/#409fc21932a9
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Re: More thoughts on CG: MT's and Big Mac's

A1Skinner wrote:You mention quiet. But a lot of other people I've talked to say they are actually louder. I know if a C206 and a 180, same engine on both. 180 has an MT and 206 has a Mac. The 180 is a lot louder...


Couldnt be further from the truth... I would chalk that up to campfire hearsay. The MT is light years quieter than the mac, and there is no debate. Because of the design, the MT only runs 2700 on a 550/520 and 2600 on a 470. At 82" (4" shorter than the mac) the tips are running considerably slower and do not crack the sound barrier like the mac.

When I was doing T&G's with the mac to get some baseline info before we swapped, it only took a handful of laps before the airport gave me a should and asked me to stop due to complaints. (the fact that this happens is for another thread. :wink: ) I know a lot of old tymers think that the classic sound makes the experience, but for me, trying to be low profile and a good neighbor is worth everything.

Quickdraw1 wrote: That makes sense with that heavy of a plane. It takes quite a bit to move the CG when dealing with a plane that is inherently heavy .
.

Yep... and its even more dramatic on an early light bird. No one can argue that the pricing on the MT's isn't now in the stoopid category. That said, look at the other choices. Traiblazer is about $5k more than the 3 blade, and the black mac, (when you add the additional cost of the spinner and bulkheads) is only a couple grand less.

The real take away for me is the realization that the 2 blade is really the best choice. Its way lighter (46lbs) easier to hand prop (if needed) and faster in cruise than the 3 blade MT or Mac all the while just being slightly less betterer out of the hole than the 3 blade MT. I have come to the conclusion that the 2 blade is for pragmatism, and the 3 blade is for ego.

I unfortunately suffer from ego, and fell victim to hubris with a 3 bade ready to be hung on my O520... But I think I will be happy there. #-o

AEROPOD wrote: I'm also shocked to hear this...
Good thing you have no idea about sarcasm. :wink:
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote: I have come to the conclusion that the 2 blade is for pragmatism, and the 3 blade is for ego.


It may not be an just an ego-based decision if you are going for the least vibration and comfort possible. The three blade is ultra smooth. Noticeably less vibration than a two blade.
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Re: More thoughts on CG: MT's and Big Mac's

Squash wrote:It may not be an just an ego-based decision if you are going for the least vibration and comfort possible. The three blade is ultra smooth. Noticeably less vibration than a two blade.


I was being a bit tongue and cheek, but yes, this is a good point... That said, I didn't find the 3 blade that much smoother than the 2 blade I ran on my 180H. They both are pretty amazingly smooth.
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Re: More thoughts on CG: MT's and Big Mac's

erased
Last edited by hotrod180 on Wed Aug 08, 2018 9:28 am, edited 2 times in total.
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna wrote:but for me, trying to be low profile and a good neighbor is worth everything.


So when are you selling your cessna's for something with a rotax?
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Re: More thoughts on CG: MT's and Big Mac's

hotrod180 wrote:Dunno about MTs on skywagons, but a guy here...


I know nothing about what you are talking about, but since we are talking about noise... #-o
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Re: More thoughts on CG: MT's and Big Mac's

asa wrote:
Bigrenna wrote:but for me, trying to be low profile and a good neighbor is worth everything.


So when are you selling your cessna's for something with a rotax?


Gliders brother... Gliders!
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Re: More thoughts on CG: MT's and Big Mac's

Bigrenna

Are you swapping governors too when you add the MT?
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Re: More thoughts on CG: MT's and Big Mac's

No. The STC doesn't require a new gov. The bird is getting a new 550 this Sept, so it a new one will be installed at that time.
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Re: More thoughts on CG: MT's and Big Mac's

erased
Last edited by hotrod180 on Wed Aug 08, 2018 9:29 am, edited 1 time in total.
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Re: More thoughts on CG: MT's and Big Mac's

hotrod180 wrote:I also guess that I'm not allowed to post on any threads you've started.


https://backcountrypilot.org/forum/plea ... care-19263

Do you consistently post more than 5 times a day?
Do you post on threads that are seeking knowledge, yet you do not possess the relevant knowledge for the subject at hand?
Does your post consist of conjecture and guesses (barring engine diagnostic threads of course) ?
Do you frequently "hijack" threads with irrelevant statements that can't even be considered tangential?
Do you offer unsolicited criticism of aircraft builders despite never having built your own aircraft nor embracing the philosophy of homebuilding?
Do you offer unsolicited criticism of others' flying despite never having done that type of flying yourself?

... The bottom line is that, before you click SUBMIT, ask yourself if you're that guy I described above.
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