What's new
Van's Air Force

Don't miss anything! Register now for full access to the definitive RV support community.

Feedback on Aymar-Demuth Propellers ?

H

humptybump

Well Known Member
Im looking for first hand feedback from people who have owned and flown an RV with the Aymar-Demuth Propeller.

I've read three NTSB reports and done the search here on VAF.

Anyone wish to add their personal experience.

Thanks in advance for your candor.
 
I installed a used Aymar-Demouth on my RV6 about 300 hours ago. My prop has no metal on the leading edge, so I avoid the rain. Early in the takeoff run I see 2280 RPM (near Sea Level); at 8500 ft and WOT it turns 2690 to 2710...just right. TAS will be just north of 200mph with Lyc O360. The only time I wished for a CS prop was in the mountains of Idaho.
 
I've been flying behind one for over 10 years. After 9 years, I upgraded to one of their composite wrapped props because of some wood degradation on my original prop. The finish had <apparently> cracked, allowing water to penetrate the top surface of one blade, damaging the wood.

I chose to replace the prop rather than to have to worry about it.

Obviously, I'm pleased with the performance of the Aymar/Demuth props or I'd have gone a different direction on the second prop.
 
My RV6 has an Aymar/Demuth. Plane has about 500hrs and an O320 150hp. Prop has protected leading edge that I've flown thru rain a few times with. I try to avoid it, and reduce rpm when I do. No problems so far. At 8500' WOT I get 190mph TAS
 
Ditto

Same experence as Kyle but mine is 11 years old. Great prop and has a Carbon Fiber leading edge with only 1 small nick in 11 years.
 
promising news

This is all promising news. Before I asked here, I was doing searches and like so many things, the bad stuff got written up and the good stuff didn't.

I'm still interested in more experiences (good and bad). At least now, I'm not feeling so nervous about flying behind one of these propellers.
 
I Like Mine....

I bought one from Mike Demuth in late 2005 and put close to 200 hours on it before doing a refurbishing job on my -4. I have a 3 blade Catto I'm going to try out. The only reason for the change is the 3 blade looks sexy on the ramp. :p

I've had no problems with it and it performs wonderfully. I'm keeping it just to have a good spare.

_______________________________
Deal Fair
RV-4 (to be flying again soon)
George West, TX 8T6
 
humptybump said:
Im looking for first hand feedback from people who have owned and flown an RV with the Aymar-Demuth Propeller.

I've read three NTSB reports and done the search here on VAF.

Anyone wish to add their personal experience.

Thanks in advance for your candor.
Click to expand...

Jim Smith with his 150 HP, auto-fuel RV-6 did a lot of GPS-derived TAS testing with his 68-72 Aymar-DeMuth and his three blade Elippse prop, and typically the Ellipse prop gave 4-5 mph more TAS from 7000' dalt to 10,000' dalt at about 90-120 less rpm and better ROC.
 
dealfair said:
I bought one from Mike Demuth in late 2005 and put close to 200 hours on it before doing a refurbishing job on my -4. I have a 3 blade Catto I'm going to try out.
Click to expand...

I hope you will report back on how the switch from the Aymar-Demuth to a 3-blade Catto performs. I personally am very interested as this is exactly the switch I have been contemplating (and mostly for the same reason :D
 
Have flown 1600 hours the last 11 years with a Demuth 68 x 74 prop. Static RPM 2350, climb RPM @ 130 mph 2450. Normally runs 300 RPM above manifold pressure at lower altitudes. Runs 2750 @ 7500 feet TAS 205mph
Tried another prop that ran more square, however, would not produce the same top speed.
Prop is painted wood. Cannot find a better overall match

Peter
 
petersb said:
Have flown 1600 hours the last 11 years with a Demuth 68 x 74 prop. Static RPM 2350, climb RPM @ 130 mph 2450. Normally runs 300 RPM above manifold pressure at lower altitudes. Runs 2750 @ 7500 feet TAS 205mph
Tried another prop that ran more square, however, would not produce the same top speed.
Prop is painted wood. Cannot find a better overall match

Peter
Click to expand...

For this post to be useful, we need to know A/C type and motor...............

I got RV6 from your profile________________
 
I purchased a new wood/composite prop from Mike Demuth about a year ago. Beautiful craftsmanship. Runs smooth. I am very satisfied.

Ron
 
I have been using a Demuth prop since 2002 on my RV-4 after my Props, Inc. propeller failed in flight. Real happy with its performance.
 
gasman said:
For this post to be useful, we need to know A/C type and motor...............

I got RV6 from your profile________________
Click to expand...

Yes , aircraft type is RV6 with a Lycoming O-320-D2J of 160 Hp. The engine by the way has 4000 hours since overhaul, compression 78/80 on all cylinders, normal oil pressure, burns 1 litre per 10 hours and still has the same static rpm as it did when I bought it at 2300 hours.
 
Last edited:
I had one on my RV6a that performed well ..... Until it failed in flight. Chucked a big wedge piece from one tip. Cant tell ya the reason, but it does wake you up.
 
Aymar-Demuth propellers!

I may have had some Mis-Information but I was told by a fellow builder here in the UK that Aymar-Demuth had stopped producing propellers at the end of 2010!
Can anyone throw some light on this? If it is wild rumour I'll set the record straight!!
 
Say what???

petersb said:
Yes , aircraft type is RV6 with a Lycoming O-320-D2J of 160 Hp. The engine by the way has 4000 hours since overhaul, compression 78/80 on all cylinders, normal oil pressure, burns 1 litre per 10 hours and still has the same static rpm as it did when I bought it at 2300 hours.
Click to expand...

4000 since overhaul! Incredible! I hope it's not a misprint because that has to be a new record. I've personally seen two go 3,000 hours but 4,000..amazing.

Best,
 
I put a previously flown AD prop on my O-360 RV7 in 2003.

I just replaced it last year with another one.

Good performance and smooth.

I had refinished the old one several times and it had a small crack in the wood grain.

It is retired and decorating the hanger wall presently.
 
Will Do!!

humptybump said:
I hope you will report back on how the switch from the Aymar-Demuth to a 3-blade Catto performs. I personally am very interested as this is exactly the switch I have been contemplating (and mostly for the same reason :D
Click to expand...

I surely will Glen. "Ole Sweetie" is being refurbished by the fine fellas at Hotel Whiskey Aviation presently; and we hope to have her going again really soon.

Jeff Hanson, there, has a 3 blade Catto on his -4 and swears by it.

Happy flying,

Deal Fair
 
pierre smith said:
4000 since overhaul! Incredible! I hope it's not a misprint because that has to be a new record. I've personally seen two go 3,000 hours but 4,000..amazing

Best,
Click to expand...

No misprint, infact our localflying club run theirs 3500 before overhaul. The mechanic says they are just starting to show wear. The secret is to fly regular, in me case three tmis a week most weeks. Just finished a trip from Toronto to the Bahamas, Sun Fun, Toronto. Arrived at Sun Fun 10 minutes before the tornado on Thursday, not by Plane by rental car, left the Plane at WinterHaven.

Peter
 
Not so fast...

Glen,

I test flew my RV4 in 1996 and over a 10 year period tested 8 props on it including an Aymar Demuth. The props included Sterba, AD, Margie Warnke, Bernie Warnke, Sensenich Metal, Catto, MT and Hertzler. I was fortunate to be able to test Craig Catto's first 2 blade RV prop on my RV4 and flew against many equal HP RV's with different props including the Catto 3 blade. With the exception of smoothness, the 2 blade Catto outperformed the three blade in every category. I sold my 4 with the MT on it and my Hertzler is also flying on an RV4 in TX. Margie's masterpiece adorns our mantle :)
So you ask which prop performed best? Hands down the MT fixed pitch 2 blade and the Catto 2 blade were nearly identical in performance with a slight edge to the MT. Margie Warnke's Claw (no longer in production, she retired) and Gary Hertzler's composite "silver bullet" prop were both excellent as well but didn't handle the rain down here like the MT.
My current 150 HP RVX has an MT 2 blade that reaches near perfection for the airframe/engine as well. The MT does very well in rain and is a certified prop world-wide in production with service centers available.
Recently, Craig built me a beautiful nickel leading edge 2 blade for the "X" and I test flew it last week. Testing showed it to be a great climb prop but way under-pitched. (3200 RPM max!) However, he has kindly allowed me to exchange it for one with more pitch.

You can't beat Craig's product and service after the sale, great guy and gorgeous props!

Smokey

www.mt-propellerusa.com
www.cattoprops.com
[email protected]
 
Last edited:
Gary Hertzler prop

I am the "guy in Texas" that has Rob Ray's Silver bullet prop. As he said, it is a wonderful propeller with perfect performance on my 160 hp RV4.
That propeller is now sitting on the shelf... I came across a Margie Warnke 3 blade "air claw". This prop performs even better than the silver bullet !
The "almost constant speed" label lives up to it's name. Static rpm to WOT at 5000 ft is 2350 to 2650. The propeller really does change pitch. The silver bullet had a rpm range of 2200 static to 2820 WOT. The climb is 300FPM better, but the top end is 2kt slower.
Whereas the bullet was a vast improvement over the sensi metal prop, the Air claw is, for my purposes, working out better than the bullet.
 
Catto delivery question......

Hi Smokey,

I understand you talk to Craig frequently. What is his average delivery time these days????

I ordered my 3 blade back in early 2007 when he was working by himself and overwhelmed with orders. I understand he has staffed up and has some help now. He told me he can get a 2 blade out faster (understandably) than the 3 blader; so can you give us a guesstimate??

Thanks,

Deal Fair
 
Maybe next week...

Hi Deal,

Yes, Craig has added staff and increased production to match demand. Thirty to forty-five days lead time seems to be the range now. Craig's props are vastly different than the one I owned for 10 years with a new blade design similar to Paul Lipps propellers and a nickel leading edge.

You might contact "smoke" and ask him if he would part with the SB. It would give you excellent performance as well.

Smokey

Parting thought: The fastest piston engine airplane for it's weight class right now is running a Catto prop as well as the previous record holder. Also, the Predator drone uses a Catto prop, great product :) Craig also manufactures Paul Lipps "Ellipse" props

http://www.youtube.com/watch?v=lstJFqHyfeg
http://www.eaa.org/experimenter/articles/2009-02_elippse.asp
 
Last edited:
Great to hear about the different props and first-person experience. I contacted Craig about a Catto prop and his suggestion was the two-blade. He said it would be a direct swap for the AD if/when I decided. Given all the news here, I'll stay with the AD for a good while !
 
> the Prince P-tip was in the shop getting the leading edge refinished.

Boy is that a common problem with his props. All it takes is a little rain . . . and I mean little.

I hear he has gone to an embedded metal leading edge. That sounds like it'll work a lot better.
 
Prop Failure

I have flown with two different two blade props and a three blade on my -4. The first two blade was a Aymar Demuth wood, and performance wise it was great. However, one prop tip departed one day and the performance was not so good after that. The others are Catto, great props.

I have heard of several instances of prop failures like the one I had, all with AD props. I think it has something to do with the way they protect the leading edge from rain. AD routs out the leading edge causing a notch in the wood, and then fills it with some kind of composite that has iron filings in it for erosion protection. I am not willing to put another one one my plane, but others obviously have a different opinion about this.
 
NTSB Report ?

Brent - I may be misinformed or just forgetful but I think I read a report of your situation. It was part of why I started this thread. It's also why I initially contacted Craig at Catto.

Given my plane came with the AD, I intend to fly it with diligent inspections.

To any of the current or past pilots with AD's; do you have an inspection procedure you use ? something you do with each flight ? something you do every 50 hours ? etc ?

I'm thinking pre-flight and inspection regiments are good for wood props in general so any suggestions are welcome !
 
You must log in or register to reply here.
Back
Top