----[Please read http://ercoupers.com/disclaimer.htm before following any advice in this forum.]----
I'm no prop expert, either, but generally length restrictions are related to vibration characteristics. In fact, if you look at the tcds for the McCauley 1A/B90 prop, you'll see that there are the same length restrictions for the various engines on which it can be installed. (look here: http://www.airweb.faa.gov/Regulatory_and_Guidance_Library/rgMakeModel.nsf/ 0/5a5d18d5be78684c85256712 006e7721/$FILE/p-842.pdf ) So, if you're flying behind a C85 and you're running at C85 RPMs then you best have a prop that's certified for a C85. There are no legal requirements as to pitch. The pitch is indirectly regulated by the static RPM requirements. Any suitable prop that meets the length requirement and the static RPM requirement is "acceptable" wrt pitch. John ========================================================================== ==== To leave this forum go to: http://ercoupers.com/lists.htm Search the archives on http://escribe.com/aviation/coupers-tech/
<<attachment: winmail.dat>>
