Lewis L55CKL-42

[1gordyk]

I have a nice GB Lewis Co. propeller.
L55CKL-42. Any idea what this may of been used on?

[Dbahnson]

I'm guessing that the "L" is for Lycoming as the "CK" by itself was used on Continental engines. See this list for aircraft that used the CK design, and if there was a Lycoming option for any of those airplanes then the prop was most likely designed for that airplane.

It's not particularly unusual to find propellers that don't exactly match the published lists, but they still used the same type certificate for production, and the type certificate often also included a range of numbers for pitch (the pitch on yours in 42 inches).

[1gordyk]

Counter clockwise rotation

Thanks for the reply dbahnson. After looking at the prop somemore i realize that it turns backwards for a small continental. It turns counterclockwise if you were sitting in the cockpit. Maybe the “L” in the prop designation stands for countrrclockwise rotation. I am wondering What continental engine turns counter clockwise and what aircraft that would be used on?? Any ideas?
See attached photo.

[Dbahnson]

You're right. I didn't notice that in the hub photo, but it's clearly a left hand thread.

Now it's a real mystery, as I don't know of any left hand thread applications for the aircraft listed on that list.

It might be worth contacting an existing manufacturer (probably Sensenich) and asking them if there was a situation where a left hand thread was utilized on a Continental engine. I'll look through some data sheets that I have to see if anything can explain it, but right now I have no answer.

[1gordyk]

Left hand lewis prop

The prop was in the back of my dads hanger buried under a bunch of other stuff. He owned a fbo at our small town of Rolla ND fron 1948 until he passed away in 2010. He was The type who never threw anything away so you can imagine there was lots of “stuff”. It sure would be interesting to find out what it is off of. Any body have any ideas??