The Cessna 120-140 Association Forum

140A owners with the O-200/Sensenich 69CK combination, would you please provide your prop pitch, static full power RPM, and your cruise RPM/IAS? 120/140 owners are welcome to chime in too!

I just purchased what seems to be one of only 2 Sensenich 69CK props available in the USA from Univair (they had 2 in stock). It is the cruise prop with 52 inch pitch. I've always prefered getting airborn as quick as possible, and planning to have the prop re-pitched to a 48 inch climb or 50 inch standard. So, I am trying to get an idea of what to expect from current owners. The prop shop gets $400 to re-pitch, so I would like to get it right the first time. The prop shop says it can be re-pitched a maximum of 4 inches.

I flew a Stinson 108-1/150 hp with a cruise prop out of Truth or Consequences, NM, 5,000 MSL. It would roll and roll, then finally the tail would come up and roll some more, eventually getting in the air. I put a sea plane prop on her, and she would almost jump off the ground at red line RPM, but would only go 85 mph IAS! Changed to a climb prop and it worked out good.

Thanks for your help.

Steve H

1948 C-90 with a 71 50 clip tip , Illinois at 677 alt. on those hot humid summer days i'm usually by myself and at 3000 ft rwy sometimes it does take a while. I had a 71 46 loner prop when we went to Tucson Az. that worked well for the mountain trip.

Is that prop a 69" prop? Is your engine a C90? If so, I suggest you try the 52 pitch before you do anything. I fly a 71-52 (actual length 70) on a C90 and I would not call it a cruise prop. With the shorter blades yours will already be more toward the climb realm.

Thanks, Jeff, for the info.

John, sorry, I should have been more specific. I have a C140A with the STC'd O-200 from a C150. That's why I'm asking for 140A owners with an O-200 for their input. I figure 120/140 owners with the O-200 would also have good info.

This is a Sensenich prop.

The 69CK is for the C150/O-200. the "69" is the length of the prop.

The C-90 uses the Sensenich 76K prop..."76" again indicating the length of the prop.

I can not find a Sensenich 7152 prop. McCauley has one. I assume your propeller is a McCauley.

Here's the Sensenich Application Guide.

https://www.sensenich.com/wp-content/up ... 91787a.pdf

It indicates the 69CK-0-52 is the cruise prop for the C150 thru 150K. Also, -48 as climb, and -50 as standard.

I am going to initially fly with the 69CK-0-52 to see what the take-off/cruise is like, but I am not expecting there to be a lot of difference between the 140A and the C150 performance with the same propeller. If I'm wrong and the cruise 52 pitch does what I would expect from a climb prop, I'll save $400! But, if it is as I suspect it will be, I will be getting it re-pitched.

Thanks guys, for your responses.

Hope some of you O-200/Sensenich guys will join in.

Steve A H

Steve,

You said that you just purchased the prop. Did the airplane come with a different prop?

Rick

Hi Rick.

I've been flying this plane with a McCauley prop. It picked up a rock and the resulting nick is to big to file out, so I had to purchase a new prop.

Univair is in the process of shipping the new prop.

Steve A H

Sorry, I missed the fact that you have an O200. I assumed you had the original C90, and that the prop you bought was approved for the (C90) engine and airframe.

That's ok John, I've missed stuff a million times, just ask my wife! In fact, she's become my brain!

I've gotten a lot of really good information from your posts over the last 5 years as a member. Your input is always welcome.

Steve A H