I just got the latest copy of FLY R/C magazine and darned if there wasn't an advertisement in there that caught my attention.

It was a whole page ad. Ugly bright green page that screamed, "THE GREEN LIGHT TO GO FROM .60 TO .75" with the "75AX Ringed" engine.

Reminds one of the RCU ad about a month or so ago. It also was for the ringed .75AX and referenced http://www.osengines.com as did this magazine ad. Well, Tower still doesn't show anything up front in the OS section about anything other than the .75AX ABL nor does the osengines.com website.

I think a ringed .75 would be a good idea. And evidently some mystery advertising writer does too.

Is there one in the works? Or does Great Planes/OS Engines just not proofread their ads?

Yes, the ads are incorrect. Because of the 3-4 month lead time required, incorrect ads can appear long after information has been corrected in the online tech notes. O.S. doesn't have a ringed 2-stroke .75-size engine.