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Sensenich Ground Adjustable Prop

FullThrottle

FRIEND
Kenai AK & Houston TX
I was wondering if anyone has the Sensenich ground adjustable prop for the 180hp Super Cub and how it compares to a Borer? I pre ordered it for my 150hp Super Cub (they are hoping to have it certified for the 150hp Cub by Oshkosh) but was wondering how it performed. They said it was a pitch of 36 adjustable to 46, and weighs 22 pounds or so less. Thanks!
 
Night and day difference. I made up a spread sheet for the local dealer who was involved in the testing and certification flights and we compared A LOT of different planes doing same day testing with the original prop on the planes then the Sensenich GA prop at various settings. Every single plane (not just cubs) showed significant improvement on take off, climb and cruise speed. On my 160 HP pacer I was over 48% shorter on take off times (17.7 seconds with 82X44 to 9 seconds at 34") on skis with a solid ice runway and better climb/cruise.

For what its worth, After a lot of testing I turned down one of the higher pitch pins that I can't use to give me a 35" pin and the 150/160 engine seems to like this pitch the best. At 34 I can turn it up and get the best take off time, but cruise suffered a few MPH. 35" and we seem to get about 1-2 seconds longer take off, but a few MPH faster than the 82X44 borer.

I have switch back to BW so I need to run the tests again just to see what the #s are on BW versus skis. The difference was enough that after testing the demo prop, I bolted my 82X44 back on for 2 flights then went and plopped my CC down and walked out the door with the new prop and I have never looked back.

Another benefit of the CF prop is instant spooling and better throttle response when your dragging it in.

I have said it before many times and I will say it again. If your running a mechanical tach have it check using an optical or digital tach. I have yet to see one that was not 150-250 RPM LOW on the top end so when your mechanical tach says your turning 2500 chances are your closer to 2300. I thought I must have had the world strongest 160 narrow deck till I checked the tach out. FWIW the optical and digital tach on the EM are within 1-2 RPM of each other.
 
I just received my prop and have it installed. I have minimal testing as of yet. Managed two take-offs before wx forced me back to the hangar so I have little to offer as of yet.
Here's what I can tell you so far:
McCauley Pawnee prop (P235AFA8442) 35.05lbs removed.
Sensenich installed with a weight delta of -14.15lbs including hardware and prop spinner.

I wanted to start with an apples to apples comparison and set it to 42" like the old prop. But, there is no pin for 42" and 43" pitch was as close as I could get with the pins. So as an initial install this where I stayed. The pitch and tracking set up is a little fiddley at first. It took two of us to set it up with a couple try's to get it in spec. I imagine I will get better at it as I make more adjustments. I don't recommend that you use an ultra sensitive digital level. Use a cheap one otherwise you will be chasing numbers.

The engine start was very fast and very quiet. This prop is soooo lite! I ran the 50% RPM requirement for 10 minutes and retorqued. Then did a static test and the tach showed 2500 leaned for best power. I did not use a light tach to check the gauge but I will.

Takeoff and climb seemed a wee bit slower but...I also installed new 31" tires with extended gear and AOSS and added 44lbs to the bird.

Here what was VERY NOTICEABLE(!) the aircraft speed was increased across the board (in the pattern). Of the two trips I made around the patch, of which I have done a thousand times...I had to pull the throttle back ALOT farther and ALOT faster to slow down.
This was VERY noticeable and totally unexpected.
More to come if Winter ever leaves. IMG_4553.jpg
 

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Why do you need a digital level? That is the beauty of the sens using the pins and not a level. Being careful on the TQ sequence and I have never had a blade out of track on the first try. As I am TQ the props I will slide the pin in and out of the holes just to make sure I feel that slight drag on each hole as I insert it and pull it out. If you don't feel the slight drag or if its really tight to try and put the pin in or pull it out, loosen up the bolts on that side of the hub and tighten up the other side and it will just slightly change the pitch and the pin should easily slide in and out with just a slight drag as it contacts the pin in the blade.
 
This is what I came up with. Too many variables in "feeling". The recorded data won't lie. All the testing we did was with 2 people. The pilot did the flying and observer did the timing and recorded the numbers. You would be amazed at how many pilots can't hold a climb and can't tell the difference in 2-3 seconds on take off.
 

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Didn’t see any data in the pdf


Sent from my iPad using SuperCub.Org


This was a blank form if the fellow above would like to use it while playing with the various pitches on the prop. I am on my work computer and don't have the ones that we filled out on hand.

My point to this is to give a base line for what you had, then do some form of regimented testing to see the actual results, I think or I feel is not a very good way to test your new prop etc. Record the numbers and see what you actually get.

I find this really useful for then I want to change pitches for the mission. If I have some CC I want to do and am not worried about maximum TO performance, I can look at my chart and know exactly what pin to use and what performance I can count on getting. Once at my destination I can swap to take off pitch and know exactly what to expect as well. Changing pitch take around 5-8 minutes if you have a spinner on.
 
How does it compare to the longer 84 or 86 inch Cattos? Can you get an equal takeoff and still cruise the same as a long Catto without adjusting pitch?

Sent from my SM-G965U1 using SuperCub.Org mobile app
 
It's $6350 no spinner and I think another $500 or so for the spinner. I'll have to dig up my notes from when I talked to them a couple weeks ago.

Availability isn't great. The O-360 prop is one or two in stock but no more on the way soon due to carbon fiber shortages all over the US. The O-320 prop is yet to be built and they're taking pre-orders for end of June delivery but they only have a few spots left and with the CF shortage who knows if they will be able to make more soon after those are sold.
 
Spinner is $735. I have had 2 O-360 props on order since Feb 2 so them having them in stock would be a surprise to me.
 
Hmmm maybe we just got our wires crossed and they meant they have the O-360 prop "ready to go" in terms of certification not in terms of stock. Could have sworn the guy I talked to mentioned 2 in stock....
 
Will you be posting your data? thanks.

This is what I came up with. Too many variables in "feeling". The recorded data won't lie. All the testing we did was with 2 people. The pilot did the flying and observer did the timing and recorded the numbers. You would be amazed at how many pilots can't hold a climb and can't tell the difference in 2-3 seconds on take off.
 
Does anyone have the testing data to post?

Also, the question of hot running engines should be answered. Apparently due to the blade root shape? ala..Whirlwind?

Mmaybe someone can give me a link to all the Whirlwind discussions since I am so busy or lazy or bad at this sites search function.

Maybe a link to a search function tutorial?

Anyway. thanks for the data Akavidfler
 
supercrow. are yu running a stock nosebowl or what? any idea where the cht issues rumor is from?
 
I don't know where the rumor comes from. Maybe is is true for some but hasn't been for me. Standard nosebowl and 10-1 compression. I should note that I purposely used a J-3 boot cowl when I built the crow 25 yrs ago because I think getting hot air out of the big side gills is important. Whether that actually makes a big difference or not I don't know but I ran the whirlwind last summer up to 85-90deg ambient air with cht (all 4 in the 380 to 390 deg. range) and the sensenich in the early fall up to 80 degs ambient with same results. 370 to 380 degs. Should note that my borer 82-43 ran in the same ranges. Hope I am not adding confusion to the thread. The instrument is the CGR 30P. I run a left rear baffle oil cooler position and the rear cyls run within 5 to 10 degs of each other. I did build an intake shroud and leaned the cooler back 25 yrs ago and lowered the oil temp about 15 degs with that mod. Air fills the shroud before entering the cooler for full frontal effect instead of feeding the cooler through a 3 inch hole in the baffle.
 
The guys that tested the props in Alaska told me they had higher CHTs with the Sensenich.
Steve, do you know if the guys in Alaska conducted their tests using good data (an full engine monitor), and were comparing apples to apples, or was this just an casual observation?
 
Steve,

Did they ever respond to your inquiry? Any word on delivery times?
thanks.
I ordered mine through Sensenich and they told me two month wait. My neighbor ordered hid through Dominion Propeller and they told him two months as well.
 
Akavidflyer. are you planning to share the data? thanks

Sorry, I got side tracked and was going to run the tests again on wheels and didn't do it. The ROC I have listed was at best angle as I was only interested at clearing the trees at the end of the runway on a short strip. When I get back home I will run the tests again on wheels and at best rate of climb speeds as well.

We heard from a one or two guys that they saw increased CHTs (10-15 deg.) That was not what we found during testing and in the certification flights as well or it would have never passed the testing.

Lane at Arctic Motor Sports in Soldotna has all the data from other planes that have been testing this prop. 907-262-5592. I am pretty sure he has sold more of these props than any other dealer and was the one involved with the certification testing as well.
 

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this was on a pa-18 with an engine that dynoed at 208 HP.

Note the cruise speeds!
 

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  • PA-18 208 HP.pdf
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this was on a pa-18 with an engine that dynoed at 208 HP.

Note the cruise speeds!
That full throttle speed at 2700 rpm of 105 mph seems slow to me. Are you on 35" tires? Do you have slats?
My 180 hp does 120 mph at 2700 rpm..... on floats. The prop is the Whirlwind 200G.
 
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