I am looking at a Stearman with a 985 on it and have a question about the prop installed, hoping I might find a little knowledge about it here.

It it is a 2D30 Hamilton Standard with model 6167 blades installed. The blades listed on the Type Certificate for the Stearman are 6101 blades.

Does anyone know of any form of approval, STC, Field Approval, etc. that might be out there for the 6167 blades being used on a Stearman?