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Propeller blade count (2, 3 and 4 blades)

Name: Propeller blade count (2, 3 and 4 blades) dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

Should I use a 2-, 3- or 4-blade propeller? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: 3 blade vs 2 blade prop, propeller blade count, 4 blade prop rc, 3 blade prop equivalent, how many prop blades, multi blade propeller, scale prop blade count, prop blade number efficiency, 3 blade prop diameter

Exact dimensions. True size, with no printing tolerance added.

sizes: 4 in table

Notes

Adding blades lets a smaller-diameter prop absorb the same power. APC's rule: with the same blade shape and pitch, a 3-blade prop equals about 90% of a 2-blade's diameter and a 4-blade about 84% (Model Aviation, APC Q&A).
This is useful for ground or scale clearance. The FAA notes large power increases drove four- and six-blade propellers on full-size aircraft (FAA Powerplant Handbook).
The file is a reference example built by Xem Studio from the numbers above. Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

Propeller blade count size chart

parameter	value or range	source
3-blade equivalent diameter	about 90% of 2-blade	Model Aviation (APC)
4-blade equivalent diameter	about 84% of 2-blade	Model Aviation (APC)
Worked example (derived)	12x6 2-blade -> ~10.8x6 3-blade -> ~10.1x6 4-blade	computed from APC rule
Reference build	10.8 x 6, 3 blades	computed

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Model Aviation (AMA), J. Smith with APC Propellers	Common Questions with APC Propellers (Mar 2021)	web	Publisher's page; dimensions are facts
FAA	Aviation Maintenance Technician Handbook - Powerplant, Ch. 7 Propellers	web	Publisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

propeller-blade-count-propeller

10.8×6 in propeller, 3 blades: each section set at the geometric pitch angle atan(P / 2πr); chord and section illustrative

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Plain text: sheet.txt · JSON: /api/geometry?object=propeller-blade-count