Sensenich 86" ID

[cmisleh]

Hi - I need help identifying this propeller, on what plane it was used, and what to do with it.

Markings are:
SENSENICH
DES 86O3700
SER 25275
HP 125
RPM 1925

Couldn't find it on the Sensenich page.

Thank you in advance
Carrie

[Dbahnson]

The model sequence doesn't quite make sense. Can you post a close up photo of the stamped information?

[cmisleh]

Attached are the pictures I have. The "nice" one is the only I've been able to find online. I think maybe from Worthpoint. This person says he has the same markings (except for serial number), and that he called Sensenich who said it might have been used on the PT-1. I didn't find that to be true.

wwii-sensenich-ryan-pt-21-recruiter_1_193ae46586c58173f0e4028c0b790918.jpg

Propellor info.jpg

Prop7_.jpg

[Mtskull]

If you google images of the Ryan PT-22, you will find that it used a propeller with a large integral spinner, exactly like yours.

https://en.m.wikipedia.org/wiki/Kinner_R-5

[cmisleh]

I'm reading that the PT-22 had a 91" propellor from sensenich. Mine is 86 inches. Sorry if I'm missing something, I"m not all that familiar with propellers.

[Mtskull]

Ryan PT-22 (and PT-21 and ST3, which were more or less the same) aircraft, were fitted with several different engines during the life of the design.
For instance, in US military service the PT-22 initially used the 125HP Kinner B5 engine but this was later superseded by the upgraded 160HP R5.

I cannot say with absolute certainty but it seems reasonable that the more powerful 160HP engine might have used a slightly larger propeller than the 125HP version.

[Dbahnson]

Originally Posted by Dbahnson

The model sequence doesn't quite make sense. Can you post a close up photo of the stamped information?

I think the best guess as to was actually stamped on the hub is "86 CS 70", which would translate to "86 inch diameter, type C hub, integral Spinner, 70 inch pitch". (I would have expected the pitch to be 76, but it looks to be zero.)

The attached photo is a little hard to read but comes from a Sensenich brochure. There were variations on the "S", as it was often followed by a "P" to indicate a plywood spinner.

Can you post a close-up of your hub? Maybe we can make more sense of that, even though it's "identical to the other guy's prop.

[cmisleh]

This is the best I could get (attached). Definitely looks like an 0, not a 6.

I tried to grab it by using paper and a pencil to rub, and the markings are too shallow to show up.

[cmisleh]

looks like the "C" in 86CS70 might have been stamped upside down.

[cmisleh]

I sent the picture a few days ago. The original markings that were attached were my markings. Here is the picture again. It appears the C could have been stamped upside down and backward making it look like an O. (?)