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  #1  
Old 12-31-2012, 08:53 PM
Warbirdsolutions Warbirdsolutions is offline
 
Join Date: Oct 2012
Location: Prospect, KY
Posts: 67
Default Looking For Input on MT Prop

All,
I have a good deal of experience with the 3 blade MT props used with IO 540 Lyc powered airplanes. In all these cases I loved them - very smooth!
I am hoping that some of you may have experience with the newer MT 3 blade prop for the parallel valve Lyc 360. There are lots of opinions out there about 3 blade props in general not performing as well as 2 blade propellers but I'm willing to sacrifice a tad of wide open performance for acute smoothness.
I don't know anyone personally using the MT 3 blade on a 4 cyl so any real life experiences would be extremely appreciated!
Thanks in advance and Happy New Year!
Brad
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  #2  
Old 12-31-2012, 09:24 PM
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RV10inOz RV10inOz is offline
 
Join Date: May 2008
Location: Brisbane Qld. Aust.
Posts: 2,271
Default

I am the last one to skimp on spending money on something that is justified, however, the Hartzell BA prop is hard to beat.

Better speed and a lot less $$$ is the biggest appeal. Maintenance and stone damage?

Smooth operation, well buy a dynamic balancing kit and keep it balanced for a very smooth cabin.

The only thing apart from that is cowl removal with a 3 blade is a pain.

Beauty is in the eye of the beholder of course
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  #3  
Old 12-31-2012, 09:57 PM
6 Gun 6 Gun is offline
 
Join Date: Jun 2005
Posts: 846
Default prop

y
Years ago the race boat was Ms Budweiser was in my home town alot because the driver was from there also IIrc it had about 6000 hp and a little 2 blade prop because 2 blades are faster.
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  #4  
Old 01-01-2013, 03:23 PM
mike newall's Avatar
mike newall mike newall is offline
 
Join Date: Jan 2005
Location: Yorkshire, England
Posts: 2,052
Default

RV7, 2 years on an IO-360 with an MT 3 blade prop.

Super smooth, great performance - no, it's not the fastest but whoo hoo, a few knots less.

It sounds absolutely ace - much better than the blappy 2 blader.

It looks super sexy.

Building an 8 with exactly the same combination.
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  #5  
Old 01-01-2013, 03:24 PM
gator gator is offline
 
Join Date: Feb 2009
Location: Naples, Fl
Posts: 82
Default

I have a MT3 blade driven by an IO360M1B on my 8. Have about 400 hrs on her and could't be happier. Probably give up a little cruise speed but very, very smooth. Also, excellent customer service and support from the MT guys in Deland, FL.
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  #6  
Old 01-01-2013, 03:59 PM
David-aviator David-aviator is offline
 
Join Date: Feb 2005
Location: Chesterfield, Missouri
Posts: 4,514
Default

I had the MT-7 electric unit with the Subby engine and loved it. Took a serious rock ding on one blade flying out of turf and had to have it repaired. The guys at Deland told me how to disassemble it and ship it in a small box compared to the crate needed with it assembled.

Deland service is most satisfactory but it ain't cheap.

After a few hundred hours behind it, I came to conclude it did run out of steam on the top end (as everyone knows) but I also came to believe it made up for it on take off performance. On one wet, soft field take off with full aft stick, the RV-7A came off the ground before max rpm stabilized and there I was hanging by the prop about 3 feet of the ground. HMMM.... what now Knute...is it going o fly out of ground effect or what. It did, just relaxed back pressure a smidgen and we were out of there.

It was as everyone says, very smoooth. With the Subby H6 it was like a turbine.

dd
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Last edited by David-aviator : 01-02-2013 at 06:44 AM.
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  #7  
Old 01-01-2013, 04:50 PM
APACHE 56 APACHE 56 is offline
 
Join Date: Jan 2008
Location: MERRITT ISLAND, FL
Posts: 360
Default Happy New Year

I have a 3-blade MT on an ?8? with an IO-390. It is smooth (remarkably so) compared to my Skybolt with an IO-540 and a Hartzell 2-blade aerobatic prop. As for the oft described ?loss of 3 knots? I find life barely tolerable in that I can only cruise at 177kts vice 180.
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  #8  
Old 01-02-2013, 01:45 AM
dcasey1 dcasey1 is offline
 
Join Date: Sep 2010
Location: Friday Harbor, WA
Posts: 46
Default Turbine Smooth MT prop on RV-8

Installed MT three blade on my RV-8. LyCon 230 HP IO360 M1S. 220 MPH at 5000' WOT and smooth as a turbine. 20 hours in phase 1. No regrets.

Dave Casey
N317DC
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  #9  
Old 01-02-2013, 04:17 AM
Andy Hill's Avatar
Andy Hill Andy Hill is offline
 
Join Date: Dec 2005
Posts: 976
Default

Brad...

I've test flown a number of RV-8s with various props. I've not done a detailed analysis, but the 3 blade MT climbs a little better, but who does climb at low IAS / full power in such an overpowered aircraft

The "b*lls out" low level top speed is about 6-7K less than the BA, and going from 180HP to 200HP makes little difference to that - the prop meets a brick wall, and the BA design is entirely about moving that brick wall. But again, who flies their aircraft round at absolutely max power?

Formation Loops between the 2 back the above up - Hartzell struggles at slow speed, MT can't keep up at high speed.

Finally, if you hanger in a tight space, 3 bladers are a pain / more subject to damage (as one poster above might expand on...)

One clear difference with the MT is idle drag. In Formation it can be great (like an airbrake), and for short fields it will help get you in (it might help you get out, but fairly academic). However, it could also catch you out in terms of poorer glide / energy loss in the flare if you are not careful - in the UK the RV-8 with the MT has to carry a warning of min IAS of finals of 70K as a a result.

Subjectively, there seem more "issues" with MT in terms of maint - blades somewhat more delicate and dealing with MT appears not always easy/cheap? The MT is lighter.

As a pure opinion, I would go for the MT if looks are most important. If you want a prop for propulsion, Hartzell BA
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  #10  
Old 01-02-2013, 07:42 PM
Warbirdsolutions Warbirdsolutions is offline
 
Join Date: Oct 2012
Location: Prospect, KY
Posts: 67
Default Thanks For The Input

I really appreciate the replies on the MT prop. If anyone else has experience with the MT on a 4cyl that would also be appreciated very much !
Brad
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