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Propeller diameter vs pitch

What do the two numbers on a propeller mean, and how do diameter and pitch trade off? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: propeller pitch vs diameter, prop size explained, what does 10x6 prop mean, propeller pitch meaning, prop diameter vs pitch, rc prop sizing, how to choose propeller size, propeller pitch inches, prop load equivalent, bigger prop or more pitch

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

sizes
4 in table

Notes

  • An RC prop size like 10x6 gives diameter first, then pitch in inches per revolution (APC nomenclature). Pitch is the distance the prop would advance in one turn with no slip (FAA Powerplant Handbook, geometric pitch).
  • APC compares pitch to gearing: more pitch gives higher top speed but weaker takeoff and climb; less pitch gives better acceleration and low-speed thrust (Model Aviation, APC Q&A).
  • For engine/motor load, APC's rule of thumb is that +1 in diameter is roughly equivalent to -1 in pitch, so a 12x6 loads about like an 11x7 (Model Aviation, APC Q&A).
  • 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 diameter vs pitch size chart

parametervalue or rangesource
Size formatdiameter x pitch (in); pitch in in/revAPC Nomenclature
Geometric pitchadvance per revolution with no slipFAA Powerplant Handbook
Load equivalence rule+1 in diameter ~ -1 in pitch (12x6 ~ 11x7)Model Aviation (APC)
Reference build12 x 6, 2 bladesAPC example

Where the files are

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

APC PropellersAPC Propeller NomenclaturewebPublisher's page; dimensions are facts
FAAAviation Maintenance Technician Handbook - Powerplant, Ch. 7 PropellerswebPublisher's page; dimensions are facts
Model Aviation (AMA), J. Smith with APC PropellersCommon Questions with APC Propellers (Mar 2021)webPublisher'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-diameter-vs-pitch-propeller12×6 in propeller, 2 blades: each section set at the geometric pitch angle atan(P / 2πr); chord and section illustrativeSTEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=propeller-diameter-vs-pitch

Propeller diameter vs pitch, isometric render of a generated part
Render of propeller-diameter-vs-pitch-propeller from the free STEP; not to scale.

Fits with

Pitch-to-diameter ratio, isometric render of a generated part
Pitch-to-diameter ratio4 sizes★ 1 file
Propeller blade count (2, 3 and 4 blades), isometric render of a generated part
Propeller blade count (2, 3 and 4 blades)4 sizes★ 1 file
Propeller helix angle and blade twist, isometric render of a generated part
Propeller helix angle and blade twist5 sizes★ 1 file
Propeller slip and efficiency, isometric render of a generated part
Propeller slip and efficiency3 sizes★ 1 file
APC propeller RPM limits, isometric render of a generated part
APC propeller RPM limits8 sizes★ 1 file
Propeller naming suffixes (E, SF, MR, P, W, N, C), isometric render of a generated part
Propeller naming suffixes (E, SF, MR, P, W, N, C)5 sizes★ 1 file

Questions

Is a 12x6 the same load as an 11x7?

Roughly, per APC's +1 in diameter = -1 in pitch rule of thumb (Model Aviation).