**McCauley Aircaft Propeller Model Designations**

**McCauley Constant Speed aircraft propeller model numbers have two important constants - one at the beginning that designates the number of blades and one at the end that specifically identifies the propeller model.**

A numerical value at the beginning of the model number in either the first or second position (i.e. B2 or 2A) indicates the number of blades. (This first constant will be followed by a two digit number value between 31 and 37 which reflects a particular McCauley design.)

**The most important designator in a McCauley Constant Speed Aircraft Propeller Model will be the two or three digits following the "C" at the end of the model number. **If there is only two digits following the “C" the propeller will be a threaded propeller and an obsolete design. If there are three digits following the "C" the propeller will be a threadless blade design and is current production. A Propeller Technician may refer to a McCauley Propeller as a C66 (threaded) or a C203 (threadless) - names which in "propeller speak" accurately identifies a McCauley Constant Speed Propeller Model.

The C200 series - two-bladed constant speed threadless non-feathering aircraft propellers

The C300 series - two-bladed constant speed feathering aircraft propellers

The C400 series - three-bladed constant speed non-feathering aircraft propellers

The C500 series - three-bladed constant speed feathering aircraft propellers

The C600 series - Garrett Turbine Engine aircraft propellers - either three or four bladed

The C700 series - Pratt Whitney Turbine Engine Propellers - either three or four bladed

The C1000 series - Pratt and Whitney Turbine Engine Propellers - five bladed

The C1100 series - Garrett engine propellers - five bladed aircraft propellers

**In addition to the Propeller Model number there is a blade model number for all McCauley Aircraft Propellers. The propeller diameter is a result of the difference between the first two digits and the dash number at the end of the blade model number**. For example in the blade model 90DA-2 the propeller will have an 88 inch diameter (90 inches minus 2 equals 88 inches). The "DA" indicates the blade design.