Test Flying Catto's New Ground Adjustable Prop! 

*_ESAB or Lincoln for TIG welder. Believe it or not, you don't need a million bells and whistles with TIG but you want enough flexibility. Don't cheap out on amperage. Get as high amp model as your electrical can handle. You may even need to run a heavier electrical line to be sure you can feed the welder all the power it needs. Welding tips and tricks has an awesome store with all kinds of goodies including the TIG finger which you're going to want. He also has a lot of good tutorials. Make sure you get large gas bottles so you don't run out of gas every 5 minutes then have to go and refill them every other day. Don't cheap out on the helmet either. You only have 2 eyes._* Doo Daa. 💯👈

Love how honest this video is. Tests a new propeller that claims all this technology then it performs exactly the same. He didnt sensationalize or anything. Interested what other people thought of that?

Love, love, love all the nerdy stuff with that Cato prop. Only understood about 10%, but very cool anyway. It would be cool to have a prop like that on my ACA Explorer, but it's a certificated aircraft anyway.

Back in the saddle (air) again! Cool.

Stoked to see you playing with 3D printing and TIG welding, both are very handy skills to learn.

Catto is a very well respected prop designer and manufacturer. I love learning that he is putting effort in non-planar prop tip design. As a note, Lonnie Prince (Prince Aircraft Co) has been selling his P-tip props for quite some time now. From what I can see, they are a form of non-planar tip claiming similar merits. I can believe, however, the Catto may be taking the idea to the next level.

I love nerdy videos, like you said that guy is on another level! loved that cfd test diagram so cool! Crazy the amount of thought/ tech that goes into props!

Back in the early '90's I had a small computer program from Hartzell where every blade profile could be simulated along with pitch, diameter and blade numbers and I found it fascinating to play with all the variables. What really stood out was the similarity to a turbocharger impeller in regards to efficiency islands within the maps. The prop doesn't work very well until it gets to its' 'happy speed' but this is also pretty close to where the tips are going supersonic....so in our case we were building an auto-engine conversion that had the ability to spin to 6000 rpm for max power but then the prop became inefficient if the rpm were dropped below about 4500 for cruise using the gear reduction ratio we'd chosen. Aero engines don't run a real wide rpm range for prop efficiency reasons and while a small Rotax is fine cruising along over 5000 rpm... a Big Block Chevy isn't so happy being run constantly up there and I'd much rather use 4500 take-off so we could cruise about 3000 which made a lot more sense to me. Props are very interesting devices!

I have long wondered about this "bigger is better, brute-force" mentality you have in 'Murica. I have an ancient Avid Flyer (the grandmother of the Kitfox) that we built in 1987. It has only a wee little 64hp Rotax 582, it's THIRD engine! Beginning with a 532, graduating to a 582 and when that unit started showing signs of wear (500+ hours) the third one was recently installed. It beats the socks of anything in our area regarding sort-field performance - even the aircraft I fly the most these days, a 6-seat H-295 Helio Super Courier! The 1987 Avid Flyer is LIGHT - hence it's great performance. My home base is Isafjordur, in the West Fjords of Iceland. Where we fly to: The Hornstrandir are of the West Fjords of Iceland.

Thanks for the video and sweet fly rod holder

Just got mine today, can't wait to try it out. Thanks for the video Trent.

Heating your hangar: you could use infrared heating - hang a few panels from the ceiling like your lights, and heat just where you are working. Much lower running cost than trying to heat the whole space.

Love the nerdy! So cool to have computer modeling and relate it to actual practices. My architect friend who is a computer whiz at architectural rendering, walk thru interiors, is now building a RC sailboat and using his skills to make molds, fabricate hull and figure out the mechanical layouts of servos......another world. Me, sticks and strings.....ha ha Love your content Trent!

Good morning from Minnesota! Great episode!

Great video on the prop. Huge market here for ground adjustable props that are simple to change like the nw Catto. I've been wondering why someone hasn't made them like this or similar. There is another manufacturer that has a prop that can be adjusted by simply inserting a wrench through the center of the spinner and turning it one way or the other. Anyway keep us posted on the prop info. Thx Trent.

This is awesome! I love stuff like this.

Like those rod holder ideas. Pretty sweet

Keep up the good work Sean!

Prop design is pretty amazing today. We flew a hand made wood prop we bought off Rutan it came off his varieze😆.

Very cool stuff.

Isn't the cruise test faulty because you don't have a spinner on?

Hey Trent. For the rod holder may I suggest printing it out of white or a light color as the black will triple or quadruple the inside temperature of the rod tube and may compromise your rods etc inside the tube. White PVC pipe with a white or cream coloured 3D print reel holder may be best. Great idea though good luck

Very interesting vid on the new prop. I just put an eProp, STOL prop on my RANS S6-S with a Rotax 921UL engine. This is an all carbon fiber 4 blade prop, ground adjustable that weighs 8.8 lbs. It pulls quite well and might be worth a try if you are still in the mood to experiement

That prop is really cool tech.

Maybe add a quick release mechanism like a bike seat or tire quick release for the clamp on your rod protector.

As a fellow left-hander I now understand why you are the way you are....haha

BERP stands for British Experimental Rotor Programme... certainly not French.

Man you should check out a Wood “almost constant speed” prop. They are fixed but have some special flexing properties. Also lightweight

Very cool. Love to see the experimenting. However, at least at this point, it doesn't seem like that new prop is buying you much. Looking forward to seeing how things progress, though. And how cool is it that you're actually helping Catto test their new prop!

Trent, I had a friend buy a low profile ski rack that he uses for his fly rods. They sit in the middle of his shell so you can’t see them but are still perfect for quickly clamping his rod. Just another idea for you!

I suppose you will be trying the new “Torroidal” Props when they become available.

Fun stuff !

Have you tried the DUC Props yet? I love mine. Increase in climb and cruise.

look into river quivers or trsxle fly rod tubes.

If its that sensitive for the shim the torque applied to the bolt would have an effect.

Re fly rods in the pipe = how do you stop the rod getting damaged from the vibrations? Any foam in there? I can imagine the line guides and tips rattling against the blank while driving.

It's brilliantly amazing to see this advanced development. I started visualizing the moment of the disc collapsing into two cones and immediately felt compelled to model the two vortex cones pressure areas as the disc size decreases and the lowest pressures of each cone crosses. It's difficult to imagine how changes between the propellor blade centerline(s) behave. That said, the bending moment of each blade culminating a net force at the fulcrum may allow a trunnion mount hub and center pin to lever a barrel against a pawl resulting in automatic cone reduction resulting in reduction of the converging cones back to the desirable larger disc where the lowest pressure vortecs remain far ahead if the propellor flange. Me thinx✌🏻👶🏻🚬

When is the under floor heating coming?

Would be interesting to see a 3 blade version. Much improved vibrations, but a little less efficient. Improved blade tips could bring efficiency close to 2 blade?

I fly a Highlander with a stock Yamaha Apex and SkyTrax gearbox. Very similar power to your 915. I use the NR SR118-2000 like yours except it’s only two blades, I’m extremely happy with its performance but you’ve motivated me to pull out my three blade hub and extra blade and see what happens to my takeoff performance. If you have a two blade hub for your NR, I recommend you try that too.

You maybe should put the screw of your clamp all the way through the printed part and melt the nut in from the other side, so the stress of the clamping force is mostly on the screw and not on the vertical layers of that printed shaft.

Bare mind I have never flown a plane before but I love the look of the 3 blade

This was interesting to watch. The only thing I think could have maybe changed it up, and I don't even know if it would have matter, the spinner cone. During your control test, you had the cone on, with the new prop test the cone was off, could have effected .1-.3 gph as well. Never know. Next time you guys test it, leave the cone off for both.

Trent - video description seems to be for a different video

Will that fly-fishing rod setup possibly be adaptable to your Kitfox, Trent?

As someone who has had an unplanned engine off emergency landing, I can safely say that Quicksilver ultralights have a steep glide angle. Like falling slightly sideways!

Gonna need one of those rod holders for my side by side please!

Trent why do you keep fussing with these fixed pitch props? Airmaster makes an incredible light weight electric constant speed prop designed for the 915. You’d have better STOL and cruise on the fly in one prop plus feathering. You wouldn’t run a fixed clutch in your snowmobile would you? Of course not!

Does the CFD program account for the amount of flexion on those blades when fully loaded? Looked like a lot of bending or was that just a trick of the camera? If that deformation is real, it seems to me that would be a loss of efficiency.

Trent, why not a Warp Drive prop? You would never worry about it coming apart.

What camera are you using during your intro?? Every time I see it I wonder what it is??? Once you work out what your shim pack is when optimized, it would be trivial to make a single shim of the correct dimension for the application

Is the current 3 blade still a constant speed prop? With changing to the new 2 blade ground adjustable, how would your back country flying be effected?

Did you hear that Brandon at Kitfox was in an accident last weekend? Might be good to check in with him and see how he’s doing.

Horses.... Fastest way to convert money to shit😂

Static thrust has been proven to have almost no correlation to dynamic thrust.

doesnt ABs filament weaken due to UV rays

I'm a bit puzzled to see that a "cruise propeller" is performing in a very similar way as the original 3 blade. I also don't understand why anyone would want a longer 2 blade propeller on a bushplane.unless you like to trim all the bushes on the runway :-). Woulden't a propeller tuned towards cimb performance be more suitable for the type of flying you do?

the best advice I got was "learn from other's mistakes, because you won't live long enough to make them all yourself!"

Think you might put the final .stl for the rod holder up for sale? I love this idea and have a 3D printer at work lol

Wouldn't you need to fly a longer distance for the flight computer to establish a more accurate reading.. just an observation as my car takes a good 5miles to reset lol keep up the cool vids.

No torque wrench on the pitch block?

You would be better off using something other than ABS pipe for the rod holders. ABS pipe will warp and bow when exposed to the sun as it has extremely poor resistance to UV. PVC would be a better choice, as it is more stable in the sunlight. You can also sand and paint the PVC if you dont like the standard white colour PVC comes in, as well, you should be able to find PVC with the exact same outer diameter as the ABS pipe you are using.

I like to think you are the head of marketing at square space

I'd say have him design a toroidal propeller for your Fox and enjoy all the major benefits....

What about a four blade like the S African bird?

Surprised he attaches the pitch block with two bolts and doesn't use a torque meter or safety wire for the bolts.

How is your law suit going with the FAA?

Is it possible that the lack of the nose cone would have an adverse effect on the flight performance of the new prop? I have no idea what kind of help that cone actually does for prop/plane performance... I just realized that you had a cone on there with your three blade, but not with the Catto prop... I have no experience with engineering; assume I know nothing.

Share this TIG learning process so some of us out here can learn along with you!

What would Mike Patey run? He'd likely make his own prop. 🙂

Anybody installing them on cubs? Very interesting. I run all cattos

5:07 what if quadro moves? 🙈

I don't see a difference between the two props, what's the price??

wouldn't this test be more effective if the tail of the plane was off the ground/level w/ the prop? aren't you losing a bit of torque through the angles or am i an idiot?

There is nothing new under the sun Trent. Propeller science is old. As I expected, besides being quieter Cato's design did not do much different at the same power (fuel burn is a very good measure of power) in terms of giving you a much better/faster cruise speed and my prediction is it won't in future either. Many people get all confused with engine RPM as they treat it as power setting which it obviously isn't. For the same power and same diameter in general you will be within 2 knots of speed at same fuel burn. That is my prediction and I would love to see if Cato can redefine what i understand. I doubt it. The main thing would be it will be quieter because of the modified tips. The tips create efficiency usually at slower airspeeds for wings (prop blades being wings that usually are operating at very high airspeeds at the tips). If you really want to see better efficiency that is somewhat significant, try and in-flight adjustable specially with your non-linear torque curve from the turbo charger. That will make a difference but it isn't allowed by regulation for Sport Pilots although MOSAIC is likely going to allow single lever operation. There is another prop from France called E- prop that has some mighty claims as well. That is also a lot of marketing and confusion although it does have one difference and that is between sea level and say 7000 feet the prop does not unload as much as others. Other than that it's so called ESR effect is a bunch of marketing when you really get down to proper numbers and measurements. Same power setting with same airplane in same conditions.

Doesn't it matter that there was no spinner when testing the new prop? It seems like that would be worth some speed.

Horseback riding lessons fun stuff ! A whole different world helps me block out the rest of the world when I do horse lessons .

Sounds quieter

Cliffhanger, Dude. Uncool.

Probably should have heated the floor in the hanger.

This prop is not for your airplane. One like it maybe, but not this one. So don't be discouraged by the numbers. This way of designing eliminates the testing and tweeking routine. Either you did the math right and it works perfect, or you didn't and then it's straight back to the drawing board, or screen in this case. The sound is sexy. No two ways about that. Vibration is a nasty tennant though, keep that in mind. Trust your gut, but check your fasteners.

Will you be flying with a spinner? That will affect your fuel consumption for sure 👍

So, the Ukrainians (Hungarians?) can build a decent prop.

BERP - British Experimental Rotor Programme, not French.