Can a Catto prop be put on a certified plane?

FORANE

FORANE

En-Route
Joined
Mar 7, 2013
Messages
3,539
Location
TN
Display Name
Display name:
FORANE
I saw a Piper Colt with a Catto Prop. The Catto Prop was one of the new ones with carbon fiber wrapped around a wood core and a nickel leading edge. I asked the owner how he could run a Catto as I thought they were only for experimental aircraft. He said the Catto was a wood prop and as such was approved for use in the plane. Is he right?
 
I'd imagine before spending that money the owner would have done a little research and due diligence
 
James331 said:
I'd imagine before spending that money the owner would have done a little research and due diligence
Click to expand...
A little more background info; the owner is an A&P...
 
I own a Colt. There might be an STC for the Catto prop, but the only propeller listed in the Colt TCDS is a Sensenich M76AM-2 metal prop.

Mark
 
I might be wrong, but I would think there would have to be an STC of some type for it to be legal. Otherwise following his logic you could slap any metal prop to say, a 172, because the 172 came with a metal prop.
 
Last edited:
tsts4 said:
I might be wrong, but I would think there would have to be an STC of some type. Otherwise following his logic you could slap any metal prop to say, a 172, because the 172 came with a metal prop.
Click to expand...

It can't be legal. From Catto's website:

Catto Propellers offers an array of modern specialized propellers for experimental aircraft.

They also have a survey going there, asking visitors to the web page if they'd be interested in a certified Catto prop. That alone implies pretty strongly that they don't make props for certified planes yet.
 
Hmm, I've got a Catto on my plane but I also thought they weren't approved for certified. I'd be interested in knowing how he got it approved on his Colt.:dunno:
 
Velocity173 said:
Hmm, I've got a Catto on my plane but I also thought they weren't approved for certified. I'd be interested in knowing how he got it approved on his Colt.:dunno:
Click to expand...

The owner is reported to be an A&P. He probably concluded that it wasn't a major alteration and installed the prop under a logbook entry. :rolleyes:

Actually, that might be exactly how the owner did it. Some A&Ps have been known to cherry pick data from a TCDS which doesn't apply to the particular model or ser. # range in question. Wood props (though not Catto props) are on the PA-22 TCDS, but only for the early, 0-290-powered versions.

Mark
 
You guys should look at the TCDS..

quote Item 1
Propeller and Propeller Accessories
The following propellers are eligible at the limits shown for diameter and static r.p.m. at maximum permissible throttle setting, no additional tolerance permitted:
1. Propeller (with Lycoming O-290D or O-290-D2 engine)
Sensenich 74FM59 or any other fixed pitch wood propeller which is rated for the engine power and speed:
Static r.p.m.: Not over 2400, not under 2200.
Diameter: Not over 74 inches, not under 70.5 inches
 
GrampaMark said:
The owner is reported to be an A&P. He probably concluded that it wasn't a major alteration and installed the prop under a logbook entry. :rolleyes:

Actually, that might be exactly how the owner did it. Some A&Ps have been known to cherry pick data from a TCDS which doesn't apply to the particular model or ser. # range in question. Wood props (though not Catto props) are on the PA-22 TCDS, but only for the early, 0-290-powered versions.

Mark
Click to expand...

Zactly.
 
GrampaMark said:
I own a Colt. There might be an STC for the Catto prop, but the only propeller listed in the Colt TCDS is a Sensenich M76AM-2 metal prop.

Mark
Click to expand...

Not true, read note 1 of the TCDS.
 
The only real question is, does a Catto prop qualify as a wooden prop?
 
Tom-D said:
Not true, read note 1 of the TCDS.
Click to expand...

Do we know if this Colt has an 0-290 in it? Many have a -D or -D2 installed under various STCs, but the stock engine is an 0-235-C1 or -C1B. Note 1 is specific to the 0-290s. We also don't know if the airplane has a Standard C of A or is Exp.

My previous comments were with reference to a stock Colt (See Note 8). That seemed like the safest assumption, absent any additional info.

Mark
 
GlennAB1 said:
Please refer to the first post in this thread.

Lord, did you read the link you posted, even Catto says they are composite.
Click to expand...
Yep. It may be wood on the outside, but it's certainly composite construction. Neat idea.
 
GrampaMark said:
Do we know if this Colt has an 0-290 in it? Many have a -D or -D2 installed under various STCs, but the stock engine is an 0-235-C1 or -C1B. Note 1 is specific to the 0-290s. We also don't know if the airplane has a Standard C of A or is Exp.

My previous comments were with reference to a stock Colt (See Note 8). That seemed like the safest assumption, absent any additional info.

Mark
Click to expand...
This Colt does not have an O-290. It has an O-360. It is not experimental though has had a number of changes besides the prop...
 
Last edited:
mkosmo said:
Yep. It may be wood on the outside, but it's certainly composite construction. Neat idea.
Click to expand...

Catto props are amazing. Speed, weight, design, looks, they have it all. They are the preferred prop in the RV world.
 
I contacted catto for my Liberty xl2 ,as I'm not happy with the mt prop,they said it can't be used on certified aircraft. My mt prop is composite,it doesn't like flying in the rain.
 
frfly172 said:
I contacted catto for my Liberty xl2 ,as I'm not happy with the mt prop,they said it can't be used on certified aircraft. My mt prop is composite,it doesn't like flying in the rain.
Click to expand...
I had a catto prop on my lancair before Craig offered leading edge nickel. rain or even mist will tear up the leading edge. I now have a mt electric prop with leading edge nickel which works well in the rain.
 
My guess is being an A&P he has an IA that signs off his annuals without looking at the airplane as most do anymore. It may not be legal but there is nobody to catch him. Now if I could only find someone like him to do the annual on my plane so I could run a Catto too.
 
Geico266 said:
Catto props are amazing. Speed, weight, design, looks, they have it all. They are the preferred prop in the RV world.
Click to expand...

They are popular but to say they are "preferred "is a stretch.
 
I've never seen an engine upgrade STC that didn't specify approved props. Especially with a Lyc 0-360 since they often have operating limitations for some RPMs. The assumption that any wood prop is approved is probably incorrect so a deviation based on incorrect information would also be incorrect. Whether he gets caught? His career, his risk.

From the FAA definitions-
Major alteration. An alteration not listed in the aircraft, aircraft engine, or propeller specifications—

(1) That might appreciably affect weight, balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting airworthiness; or

(2) That is not done according to accepted practices or cannot be done by elementary operations.
Click to expand...
 
Last edited:
Tom-D said:
You guys should look at the TCDS..

quote Item 1
Propeller and Propeller Accessories
The following propellers are eligible at the limits shown for diameter and static r.p.m. at maximum permissible throttle setting, no additional tolerance permitted:
1. Propeller (with Lycoming O-290D or O-290-D2 engine)
Sensenich 74FM59 or any other fixed pitch wood propeller which is rated for the engine power and speed:
Static r.p.m.: Not over 2400, not under 2200.
Diameter: Not over 74 inches, not under 70.5 inches
Click to expand...



If this is accurate, it sure looks like a wood prop to me, complete with wood shavings everywhere :D



image.jpg




Is there a certain percentage of the prop which has to be made of wood for it to be called a "wood" prop? Based on that photo, I'd say the mass majority of the catto prop is wood.
 
Just because it says you can use any wood prop, the implication is that it has to be a certified prop, which the catto is NOT (currently).
 
flyingron said:
Just because it says you can use any wood prop, the implication is that it has to be a certified prop, which the catto is NOT (currently).
Click to expand...

Yeah. That. I bet the FAA would disagree with the owner.
 
First let me say, I'm clearly no expert on regs, but that doesn't stop me from having an opinion.

Now, isn't this actually a TSO/PMA question?

Here is the exact entry for the landing light from my TCDS:

Specification pertinent to all models:
~~~~~~~~~~~~~~~~
303. Landing lights, General Electric 4522

So, does it matter where I buy the GE model 4522? Does it have to be from a TSO/PMA source? For clarification, I bought one online from a non-av distributor and installed it as an owner with a logbook entry. No TSO/PMA.

Hmmmmm,
 
flyingron said:
Just because it says you can use any wood prop, the implication is that it has to be a certified prop, which the catto is NOT (currently).
Click to expand...

If a certified prop was required the TCDS would say "Any certified wooden prop"

It doesn't.
 
docmirror said:
Now, isn't this actually a TSO/PMA question?
Click to expand...

Not really, the TCDS is the type design of the make / model of the aircraft, when it says "any" it means just that.
 
Tom-D said:
Not really, the TCDS is the type design of the make / model of the aircraft, when it says "any" it means just that.
Click to expand...

I think you're right, and that makes logical sense. My reasoning is because below that the TCDS calls out specific makes, models, and design spec:

301. Generator
(a) 25 a. Delco-Remy P/N 1101879 or 1101886

or (b) 35 a. CMC P/N 533730 (includes CMC generator 532701 equivalent to Delco-Remy 1101887

or (c) 50 a. CMC assy. P/N 539829 (includes CMC generator 539538 equivalent to

Delco-Remy 1101888) or Delco-Remy P/N 1101908 16 lb. (+42)
Models 35 (S/N D-3351 through D-3698), E35, F35, G35

These are type and design specific, and a deviation from these would then, and only then require a TSO/PMA showing that the new design meets the specifics of the original TCDS entry. Alternately, it could be approved via the STC process as a supplement.

Now, back to the prop. Since the TCDS used the words 'any......' based on the statements of qualification in the verbiage, it doesn't require a TSO/PMA to go on a cert aircraft. Weird, that one could go get a 2x4, carve it to shape, and meet the requirements for power and speed and that is basically that.
 
Maybe the guy has a field approval or some other thing for it.

I've seen some weird stuff lately, like an LOA signed by a FSDO to fly a 1968 Cessna 177 with one cabin door removed. :lol: Just strange.
 
Tom-D said:
If a certified prop was required the TCDS would say "Any certified wooden prop"

It doesn't.
Click to expand...


The TCDS says its certification basis is CAR 3, which states this: § 3.416 Propellers.
(a) Propellers installed in certificated airplanes shall be of a type which has been certificated in accordance with the provisions of Part 14 of this chapter.
 
Grum.Man said:
Now if I could only find someone like him to do the annual on my plane so I could run a Catto too.
Click to expand...

Put the metal prop on before you take it in for annual and pull it back off after you get it back...if you don't care about the chance of insurance claim issues or getting ramped by a knowledgeable fed. But why would you want a Catto on the Grumman? Won't perform any better. Less vibration is about all.
 
Last edited:
docmirror said:
Now, isn't this actually a TSO/PMA question?
Click to expand...
No it isn't really.

TSO is a neither a necessary nor sufficient to approve installation for most parts (props included). A TSOA or PMA *MIGHT* help, though again in this case, I would suspect that the prop needs full up type certification.
 
flyingron said:
No it isn't really.

TSO is a neither a necessary nor sufficient to approve installation for most parts (props included). A TSOA or PMA *MIGHT* help, though again in this case, I would suspect that the prop needs full up type certification.
Click to expand...

Thanks, I'm not remotely up on the parts/acc regs, but props are pretty important so it would make sense it needs it's own TC. The wording in the CAR TCDS though does seem rather vague.

It's like the wording in my TCDS concerning the battery I just wanted to replace. The statement says exactly: "Battery a) 12V 33 A hr" and then in sub-para b) it calls out a specific mfg and type. But, I found a non-TSO batt that fits sub-para a, as 12V and 33 Amp/Hr, and that seems to fit the req of the TCDS.
 
James331 said:
If this is accurate, it sure looks like a wood prop to me, complete with wood shavings everywhere :D



image.jpg




Is there a certain percentage of the prop which has to be made of wood for it to be called a "wood" prop? Based on that photo, I'd say the mass majority of the catto prop is wood.
Click to expand...

If it is wood combined with anything else it is composite.
 
GlennAB1 said:
If it is wood combined with anything else it is composite.
Click to expand...

All the metal wood props I've seen have metal on the leading edges, does that make them all composite?


Honestly I'm not trying to say I know anything much on this subject, just find some of the ambiguity interesting.
 
Last edited:
You must log in or register to reply here.
Back
Top