NavionInfo.com • Navion Aircraft Forum & Tech Database

We recently found a reprint of the original Hartzell 12X20 Propeller Manual for the "bladder" or diaphragm prop that the majority of Navions left the factory with. You do occasionally still see a Navion with a 12X20 or 12V20 prop, and the 12 is also the predecessor to the more modern HC-D2(V, MV)20 "bladder" prop which is still in current production. This manual is mostly a curiosity at this point, as it's been long-since superseded -- but we found it helpful recently when the current manual, manual 140, seemed to have some conflicting information about installing the oil transfer unit. It was nice to be able to find this old 12X20 manual as a "tiebreaker". We've uploaded it to our database for your perusal:

http://www.navioninfo.com/files/hartzell12x20.pdf


Also, here's a link to the CURRENT Hartzell Manual 140 for the "bladder" prop:

https://hartzellprop.com/MANUALS/140-0000-A.pdf


And, the current manual 174 for the "dome" prop:

http://hartzellprop.com/wp-content/uplo ... R02-AW.pdf