MT Propellers

captainron · #1 01-26-2007, 08:35 AM

I'm interested in feedback from anyone using an MT propeller. Specifically, performance, smoothness, maintenance issues, and any other reasons to justify purchase over a Hartzell prop. Any negatives?
Thanks in advance!

JonJay · #2 01-26-2007, 09:34 AM

My neighbor has one on his RV8. Very smooth. He had two problems; A crack in the back spinner bulkhead after about 20 hours, a known issue, and a leak in one hub after about 140 hours. The factory sent him a new modified parts for the spinner and repaired his hub in about two weeks turn around time. he was very please with their service. They did not know why the Hub leaked, they just rebuilt it.

alpinelakespilot2000 · #3 01-26-2007, 09:37 AM

You might explore the reasons why Van's abandoned the MT prop on their RV-9A in favor of a Hartzell. It's written up in one of the RVators.

flyboykelly · #4 01-26-2007, 09:46 AM

We have an MT three blade on our RV-8. The propeller is very smooth and looks great on the aircraft, but some words of caution. Be sure that the propeller is matched to the engine. We have had some problems with the metal leading edges delaminating and we have had to send the propeller out for repair due to this. Also there are some performance issues with this prop. We have a 200 hp engine and we are 10kts slower than a similar RV-8 with 180 hp 2 blade metal hartzel. When Vans did their testing different models of propellers they concluded that the MT propeller was the slowest of all models available. My advice if you are looking for performance is to go with a two blade fixed pitch cruise prop or a two blade metal hartzel. If you aren't as concerned with performance but want a GREAT looking propeller then go with the MT three blade. Personally I am building another RV-8 and am installing an ECI IO-340 stroker and a two blade metal fixed pitch cruise prop. Best of Luck, Brian

Bob Brown · #5 01-26-2007, 09:51 AM

There's lots of props out there...instead of just saying Hartzell or MT, it would be helpful to know which props you want to compare, and would also be helpful for posters to specify which prop they are referring to.

One of my neighbors just switched from the Hartzell BA prop (from Van's) to the MT (MTV-15B) prop, which is the two bladed blended airfoil prop (w/aluminum blades). It should be an interesting comparison since he has a good record of his "before" speeds in his 8A and the Hartzell BA setup. He's running a fuel injected Superior IO-360.

His initial response is very positive, but no speed numbers yet. FWIW, my MTV15B setup is smooth like glass, but that's only a subjective observation and not reliant on any vibration analysis. This is a certified prop that is being used on some certified planes running Lyc engines, but not with electronic ignition.

One thing to think about when comparing prices is that the MT props generally come with a beautifully fit balanced and finished spinner, a balanced powder coated front support ring already mounted to the prop hub, balanced covers (that hide the opening in the spinner at the base of the blades), and a complete powder coated backing plate. Someone who has done all of this can give you some idea of how much time it would take to do this in your shop. There's not that much difference in price when you consider these items and your time.

JoeBlank · #6 01-26-2007, 11:06 AM

Hi,
Check out Randy Lervolds site for his extensive prop testing with the RV-8. Very well done...

http://www.romeolima.com/RV8/Prop.htm

Joe Blank
RV-6
N6810B

Bill Palmer · #7 01-26-2007, 12:28 PM

Ron,

IMHO, you might also consider the constant-speed Whirlwind 200RV propeller. Here's the link to Randy Lervold's Hartzell vs. Whirlwind propeller testing:

http://www.romeolima.com/RV8/Prop.htm

Randy didn't test the MT, though.

I have a friend, Robert Paisley, who has a three-blade, variable-pitch (electrically-controlled) MT propeller installed on his really nice Eggenfellner-Subaru-powered RV-7. His RV-7 is one of the fastest RVs in Southern California. That being said, Robert says that if you elect to install an MT, he recommends that you order a narrower-chord model than what MT conservatively recommends for a 200hp engine. He found that he was over-propped with MT's originally-recommended propeller. He thought the propeller was more suitable for a 260hp engine.

Robert switched to a narrower-chord MT model and literally took off! I suspect that some of the reported MT performance issues result from a mismatch between the MT prop, engine, and RV. With the right MT propeller, it appears that the MT is competitive, in terms of performance, with both the Hartzell and Whirlwind propellers. I'm sorry that I don't have Robert's MT model numbers for you, but I know Robert occasionally monitors these forums and is a member of the SoCAL RV List on Yahoo, so you should be able to contact him if you're interested.

One thought: After flying in Robert's RV-7 which has a well-balanced MT propeller/Subaru engine combination, I can say that I've never flown in a smoother-running RV. I've flown in several terrific RVs with Lycomings and Hartzells, but it's like riding on a Harley (Lycoming/Hartzell) versus a Honda Gold Wing (Subaru/MT). I suppose if you're a "Harley Guy," you'll like the Lycoming/Hartzell; if you're a "Cruiser," you'll like the Subaru/MT. That's not to say that Lycoming/Hartzells aren't smooth; it's just that Subarus/MTs are smoother. One more thought: A three-blade prop like the MT on Robert's RV-7 simply looks good - - There's no denying that!

Since I'm building an RV-8A to be powered by a relatively heavy 200hp, angle-valve Lycoming, I'm leaning toward the Whirlwind 200RV, mainly to save 18 pounds on the nose versus the nice, but heavier, blended-airfoil Hartzell. That being said, if I were installing a lighter 180hp, parallel-valve Lycoming in an RV-8 or 8A (or my 8A's "as built" weight and balance turns out to be different than I expect), I'd be installing a Hartzell. Note: For an RV-7, it may be best, for weight-and-balance reasons, to have a relatively heavy Hartzell up-front - - you should check this out with the RV-7 community.

I have also been tempted to purchase the MT as well, since it's a well-proven certified design, but the Whirlwind 200RV (with McCauley hub) appears to be a better value, and the 200RV is now past its initial teething issues (cracking spinner bulkheads, as I recall - - the blades and hub have been fine). Personally, and excepting variable-pitch versus fixed-pitch performance differences, I don't think there's all that much difference in propeller performance if you achieve the right propeller/engine/RV match. I would suggest that weight and balance, plus price, are possibly bigger factors in propeller selection than relative performance. That's just my personal opinion, though. Bottom Line (as always): Select the one you like!

Best Regards,

Bill Palmer

Steve Sampson · #8 01-26-2007, 03:20 PM

Ron - I have just ordered my second MT. My reason for an MT over Hartzell would be weight and smoothness. I put a few thoughts regarding 2 blades .v.3 here. They might also interest.

RV7Guy · #9 01-27-2007, 01:06 AM

My neighbor has a MT on his Lancair and is changing it out for a Hartzell Semitar. The MT has cracked several times. A few others I'm aware of have had problems.

I have the Whirlwind 200RV on my 7 with ECI IO 360. I had a seal problem because of improper initial assembly and the spinner backplate bracket cracked. The backplate issues have been resolved at the factory. No other problems nearing 200 hours. Performance is excellent and the prop is very smooth.

RV6 owner, Robbie Attaway, had an Aero composites prop on his plane. ($14,000). It cracked twice in a very short time so he gave it back to them. He ordered a Hartzell Blended Airfoil with a 5 month lead time. My neighbor has a WW 200RV that he won't be using for a few months so Robbie is "renting" it from him. He has been flying this for a few hours now and said his plane is faster and smoother than it has ever been. I believe he will cancelling his Hartzell order and going with the Whirlwind.

WW is US owned and operated and provides fantastic customer support.

N395V · #10 01-27-2007, 06:25 AM

I have 3 blade MTs on both my planes. The 1 on the F1 has 500 hrs and the Radial Rocket has a little better than 50 hrs.

Trouble free, look great and perform well.

I expect a 3 blade Hartzell would look great, be trouble free and perform well.
Dealing with the supplier was a pleasant experience and I expect service will be excellent should I ever need it.

Current delivery time on MT props is 16 weeks and on both my props they met their delivery date.

I picked MT solely for weight considerations and reccomendation of others.

If weight is not an issue for you I would go with Hartzell and save a few bucks. If weight savings is important I would consider MT as an option. Don't have any experience with whirlwind or Catto.