Props for PA18A 150

[Bob Stern]

I just measured my prop from tip to tip and it is 84". I have a 19" clearance to the pavement when the plane is sitting on the tail wheel. The climb performance is great and cruise at 22.5 is 95mph. Is this a standard size prop for a super cub? I was also wondering what my clearance might be when I do wheel landings. Any thoughts or advice.

Sent from my SM-T560NU using SuperCub.Org mobile app

[KevinJ]

Are you sure it’s not an 82-43/44 borer?

[Bob Stern]

That is Greek to me. Is that a standard type of prop for this plane?

Sent from my SM-T560NU using SuperCub.Org mobile app

[stewartb]

What do your logs say?

[KevinJ]

Or take your spinner off and see what the hub says.

[mvivion]

What these guys ^^^ said.

IF that is indeed an 84 inch prop, it’s not legal, unless someone found that long a prop and got it field approved.

Much more likely, that is an 82 inch diameter “Borer” prop. The prop designation is diameter first (82) then the prop pitch (for a Borer it’s typically somewhere between 41 and 44, and represents theoretically the forward distance the prop would pull itself through the air or some dense medium IF there was no drag or other factors involved, a theoretical measure).

As Kevin suggested, pull the spinner off and look at the side of the prop hub....it should have the designation stamped there.

MTV

[Bob Stern]

Thanks, I can understand that. I have come a long way but have much further to go. Thanks again.

Sent from my SM-T560NU using SuperCub.Org mobile app

[dgapilot]

The “standard” Supercub prop is a Sensenich M74DM-53 to 58. You have a McCauley prop, most likely a Borer prop as others have said. There would need to be an FAA Form 337 in your paperwork for that to be legal. If you are not aware of your responsibilities as an aircraft owner as it relates to required documentation, I would strongly suggest you get ahold of your mechanic and pay him for a couple hours training!


Sent from my iPad using Tapatalk

[stewartb]

If he doesn't have required documentation he should call his mechanic and fire him.

[Fortysix12]

Locate the STC for the propeller. Read it and be sure the aircraft records and equipment comply. STC SA00562SE can be bought from cub crafters.

http://store.cubcrafters.com/McCaule...ly_p_1860.html

[dstr59]

Sounds like an inaccurate measurement.
get that spinner out of the way, check model designation on prop. Verify in records. And report back!

[md11freighter]

I just pre-ordered the Sensenich ground adjustable prop. I can’t wait to try it out! There may be quite a few used Borer props on the market if they really are as advertised.

[akavidflyer]

I just pre-ordered the Sensenich ground adjustable prop. I can’t wait to try it out! There may be quite a few used Borer props on the market if they really are as advertised.

They really are. I think the 2 big ones, WW and Sensinich are really close in performance, but the Sensenich wins hands down for ease of pitch changes.

FWIW, the pitch pins that come with it are in 2" increments. My 160 doesn't like anything over 38 (that's only if I want to go faster but not get off the ground quick). I took the 40 size pin and turned it down to 35 and that really seems to be the sweet spot for the 150/160 HP engines. Still faster in cruise than the 82/44 borer but gets me off the ground MUCH quicker. We have tested it on A LOT of different planes now and ALL have shown a major improvement over the Borer prop (not to mention its 12 pounds lighter and the throttle response is instantaneous)!
When playing with the prop, CHECK YOUR TACH!!! None of the mechanical tachs we have tested were even close. Typically they have been 150-225 RPM off on the top end so the guys that thought they were turning 2700 on take off (like me) were only getting 2475-2550. I was really wondering why I was cruising so slow at 2450 (turns out I was only turning 2250). Optical tachs are cheap and my new digital tach reads within a few RPM of the optical tach now.

[MoJo]

The “standard” Supercub prop is a Sensenich M74DM-53 to 58. You have a McCauley prop, most likely a Borer prop as others have said. There would need to be an FAA Form 337 in your paperwork for that to be legal. If you are not aware of your responsibilities as an aircraft owner as it relates to required documentation, I would strongly suggest you get ahold of your mechanic and pay him for a couple hours training!


Sent from my iPad using Tapatalk

not saying it is right, but I have seen an exception to this rule. A reissue of an airworthiness certificate while non standard prop is already installed.

[dgapilot]

not saying it is right, but I have seen an exception to this rule. A reissue of an airworthiness certificate while non standard prop is already installed.

Yeah, I’ve done that where an airplane comes back from Canada or another bilateral country, and their CAA approved the other prop. That’s about the only way, and if that’s what you hang your hat on, you better keep a copy of the 8130-6 application for airworthiness certificate with the DARs signature. That’s your only document authorizing it. If it doesn’t have an approval from another CAA, then no joy! DARs have to conform the airplane to the TC or other approved data.


Sent from my iPhone using Tapatalk

[flynlow]

They really are. I think the 2 big ones, WW and Sensinich are really close in performance, but the Sensenich wins hands down for ease of pitch changes.

FWIW, the pitch pins that come with it are in 2" increments. My 160 doesn't like anything over 38 (that's only if I want to go faster but not get off the ground quick). I took the 40 size pin and turned it down to 35 and that really seems to be the sweet spot for the 150/160 HP engines. Still faster in cruise than the 82/44 borer but gets me off the ground MUCH quicker. We have tested it on A LOT of different planes now and ALL have shown a major improvement over the Borer prop (not to mention its 12 pounds lighter and the throttle response is instantaneous)!
When playing with the prop, CHECK YOUR TACH!!! None of the mechanical tachs we have tested were even close. Typically they have been 150-225 RPM off on the top end so the guys that thought they were turning 2700 on take off (like me) were only getting 2475-2550. I was really wondering why I was cruising so slow at 2450 (turns out I was only turning 2250). Optical tachs are cheap and my new digital tach reads within a few RPM of the optical tach now.

I would like to see numbers comparing the borer 82/41 ..150 horse to Sensenich. Ground roll etc

I ran a McCatto on a 0-290 and loved the ‘lighter’ and of course the performance but with my 0-320 I would like ‘legal’ also.


Sent from my iPhone using SuperCub.Org mobile app

[hotrod180]

It's been several days but the OP hasn't posted the model number of his prop yet. ??
I believe that there's an 84" borer available for the 180hp SC,
guess it could be installed on a 320 but you'd need different drive lugs on the flange?

[Steve Pierce]

The 84" McCauley that I have been around is the 1A200 on the Pawnee.

[PA-22/20-160]

The 84" McCauley that I have been around is the 1A200 on the Pawnee.

Pawnee prop is 1A235

[Steve Pierce]

Pawnee prop is 1A235

That's it, only 84" I have been around.

[KevinJ]

If it is 84”, I’ll trade you for a legal 82”. I suspect it was measured with a faulty measuring apparatus. I have two of them. One of them is used to measure TO and landing distance. It says I’m 20’ shorter. I also have one to measure height and length. It measures 2” longer

[Bob Stern]

Thanks to all of the great responses. I hope to have a chance to get to the hanger this weekend and I will do more investigating and figure out exactly what I have. Thanks and in will post the results.


Sent from my SM-T560NU using SuperCub.Org mobile app

[Kecouch]

I also just ordered the new Stensenich adjustable prop (5-8 weeks out). I have an acquaintance installed one on his 0360 and has seen excellent results. I am excited to see how it performs for me!

[mvivion]

When playing with the prop, CHECK YOUR TACH!!! None of the mechanical tachs we have tested were even close. Typically they have been 150-225 RPM off on the top end so the guys that thought they were turning 2700 on take off (like me) were only getting 2475-2550. I was really wondering why I was cruising so slow at 2450 (turns out I was only turning 2250). Optical tachs are cheap and my new digital tach reads within a few RPM of the optical tach now.

THIS ^^^^ Virtually every mechanical tach I've been around turned out to be inaccurate, some pretty ugly as noted here. There are a lot of optical tach checkers around, find one and borrow it if you're running a mechanical tach.

Or, just install an electronic tach. They work and they're actually accurate.

MTV

[Kecouch]

Thanks for the advice, I will certainly investigate my tach options for digital.

[Steve Pierce]

I also just ordered the new Sensenich adjustable prop (5-8 weeks out). I have an acquaintance installed one on his 0360 and has seen excellent results. I am excited to see how it performs for me!

I have been flying one and am quite impressed over the Borer.

[supercrow]

I am at 2 yrs now with the Whirlwind and Sensenich composite props. Love them both. The sensenich is easier to change pitch, but both work very well. The sensenich is 82" vs the 80" Whirlwind, but both are an improvement over the Borer. I have flown the Borer's since 1981 and I sold the 82/43 I have been flying in recent years. Much smoother as well. Don't see myself going back unless these don't hold up for some reason; and I see no issues at this point. The protective edge is also tougher than alum. for float use. It has all been positive for me.

[TurboBeaver]

If you live in Skiplane country, or messing around off Sandbars, these new composite props
have a huge advantages over metal props, besides ditching a ton of weight off the nose for a better CG , in the event you wind up hitting the prop weather on wheels or skis, the composite prop will instantly fly into pieces protecting your crankshaft! Big difference between $3k and 30k to rebuild an engine with a metal prop wrapped
your cowling and a big time bent flange. Cheap Insurance for your engine. Plus the advantage if your headed out on a long trip: of simply twisting blades to a cruise configuration is big option ,compared to beating the air to death with a long flat STOL type prop. Many plus's to these new composite props.

[mvivion]

As a long time user of composite props on ski, wheel and float equipped planes, I’d add that even if you don’t really whack your prop as Turbo describes, the hard metal leading edges installed on most composite props virtually eliminates LE erosion from water, snow and sand. That erosion can require frequent filing of aluminum leading edges.

I know, i know: proper pilot technique goes a long ways to reducing prop LE erosion, but anyone actually using these things gets there, like it or not. Extended gear has helped, also, but.....

MTV

[MoJo]

There are a lot of colors to choose from... since they are composite, would white be better? And spinner or no spinner?