# Propeller naming suffixes (E, SF, MR, P, W, N, C)

> What do the letters on APC propellers mean?

- Category: Aircraft design › Propellers
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/apc-propeller-naming/ · JSON: https://xemstudio.com/api/geometry?object=apc-propeller-naming · Plain text: https://xemstudio.com/objects/apc-propeller-naming/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files Xem Studio Design License (free to use and sell from, not to redistribute as files: https://xemstudio.com/license/)
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

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

## Notes

- APC stamps diameter x pitch on the blade, followed by letters: E thin electric, F folding, MR multirotor, SF slow flyer, R reversible (all electric-only); W wide chord, N narrow, NN very narrow, P pusher/reverse rotation, C carbon (40% carbon / 60% nylon) (APC Nomenclature).
- No letters means a standard right-hand Sport prop for IC engines that can also be used on electric motors (APC).
- 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.

## Sizes

| parameter | value or range | source |
|---|---|---|
| E / F / MR / SF / R | thin electric / folding / multirotor / slow flyer / reversible | APC Nomenclature |
| W / N / NN | wide / narrow / very narrow chord | APC Nomenclature |
| P | pusher (reverse rotation) | APC Nomenclature |
| C | 40% carbon / 60% nylon by weight | APC Nomenclature |
| No suffix | standard right-hand Sport prop | APC Nomenclature |

## Where the files are

- APC Propellers: [APC Propeller Nomenclature](https://www.apcprop.com/wp-content/uploads/2023/05/APC-Propeller-Nomenclature.pdf) — web — Publisher's page; dimensions are facts
- Model Aviation (AMA), J. Smith with APC Propellers: [Common Questions with APC Propellers (Mar 2021)](https://www.modelaviation.com/node/2115) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/apc-propeller-naming/index.json · license: https://xemstudio.com/files/hardware/apc-propeller-naming/LICENSE.md

- apc-propeller-naming-propeller: [STEP](https://xemstudio.com/files/hardware/apc-propeller-naming/apc-propeller-naming-propeller.step) · [STL](https://xemstudio.com/files/hardware/apc-propeller-naming/apc-propeller-naming-propeller.stl) — 10×4.7 in propeller, 2 blades: each section set at the geometric pitch angle atan(P / 2πr); chord and section illustrative

## Questions

**Is an E prop OK on a glow engine?**

No; electric props should only be used with electric motors (Model Aviation, APC Q&A).

## Fits with

- [Propeller diameter vs pitch](https://xemstudio.com/objects/propeller-diameter-vs-pitch/)
- [Pitch-to-diameter ratio](https://xemstudio.com/objects/pitch-diameter-ratio/)
- [Propeller blade count (2, 3 and 4 blades)](https://xemstudio.com/objects/propeller-blade-count/)
- [Propeller helix angle and blade twist](https://xemstudio.com/objects/propeller-helix-angle-blade-twist/)
- [Propeller slip and efficiency](https://xemstudio.com/objects/propeller-slip-efficiency/)
- [APC propeller RPM limits](https://xemstudio.com/objects/apc-propeller-rpm-limits/)