Surface drive (surface-piercing propeller) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/surface-piercing-drive/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
Catalog version: 2026-10-20

Sizes: see table below
- A surface drive runs the propeller only partly submerged near the water surface. Removing shafts, struts and hubs from the water cuts appendage drag, and the prop can be large and lightly loaded; ventilation replaces cavitation (ITU lecture).
- Drawbacks are vibration, poor reverse, difficult turns, harder set-up and poor efficiency at low rpm. Cleaver props suit speeds above ~50 knots (ITU).
- RC 'stinger' drives position the prop similarly; racers report no difference in hull behaviour if the prop sits in the same place (Model Gas Boats forum).
- The file is a reference example built by Xem Studio from the numbers above (44 mm x 1.4 pitch ratio RC mono prop (SV Design).). Sizes the sources do not fix are illustrative; scale the example to your own vehicle.

parameter  value or range  source
Cleaver prop speed  above ~50 kn  ITU (Takinaci)
Draft  can be ~half a prop diameter  ITU (Takinaci)
RC shaft height  3/8-1/2 in above keel  Model Gas Boats forum
RC prop example  44 mm dia, 1.4 pitch ratio  SV Design (Stealthwake)

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Istanbul Technical University (A. C. Takinaci): Advanced Propulsion Systems, Week 14: Surface Piercing Propellers — web — Publisher's page; dimensions are facts — https://web.itu.edu.tr/takinaci/dersler/advpropsys/Week_14/SurfacePiercingPropellers.pdf
- Model Gas Boats forum: Stinger drive versus strut support set up — web — Publisher's page; dimensions are facts — https://modelgasboats.com/forum/13-ask-the-editors-discuss-articles-general-boat-questions/16025-stinger-drive-versus-strut-support-set-up?start=0
- SV Design: Pro Boat Stealthwake upgrades info (Feb 2022) — web — Publisher's page; dimensions are facts — https://myplace.frontier.com/~sv_design/Pro%20Boat%20Stealthwakes%20Upgrades%20Info%20SVC_Feb-2022.pdf

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/surface-piercing-drive/index.json
API: https://xemstudio.com/api/geometry?object=surface-piercing-drive