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Aileron

Name: Aileron dimension sheet
Creator: Xem Studio
License: https://creativecommons.org/licenses/by/4.0/

How big should ailerons be? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: aileron size, aileron sizing rc, how big should ailerons be, aileron chord percentage, aileron throw, strip ailerons, barn door ailerons, aileron deflection, adverse yaw

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

sizes: 7 in table

Notes

Ailerons on the outboard trailing edges move in opposite directions to roll the aircraft; the down-going aileron's drag yaws the nose away from the turn (adverse yaw), worst at low speed and large deflection (FAA PHAK ch.6).
Sadraey's typical values: aileron area 5-10% of wing area, span 20-30% of wing span, chord 15-25% of wing chord, inboard edge at 60-80% semispan, max deflection about 30 deg, though he recommends keeping it under 25 deg to avoid aileron stall.
A Cessna 182 uses 20% chord ailerons from 46% to 95% semispan with 20 deg up / 14 deg down (Sadraey Table 12.1).
Used on: Cessna 182, Air Tractor AT-802, Gulfstream 200.
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.

Aileron size chart

parameter	value or range	source
Sa/S	0.05-0.10	Sadraey ch.12
ba/b	0.20-0.30	Sadraey ch.12
Ca/C	0.15-0.25	Sadraey ch.12
Inboard edge bai/b	0.6-0.8	Sadraey ch.12
Max deflection	~30 deg; keep < 25 deg up and down	Sadraey ch.12
Cessna 182	Ca/C 0.2, 0.46-0.95 semispan, 20/14 deg	Sadraey Table 12.1
Reference build	chord 200, 20% aileron, 300 mm long, 20 deg	Sadraey ranges

Where the files are

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

FAA	Pilot's Handbook of Aeronautical Knowledge (FAA-H-8083-25), Ch. 6 Flight Controls	web	Publisher's page; dimensions are facts
Universidad de Sevilla course files (Sadraey, Aircraft Design, Ch. 12)	Design of Control Surfaces (Aileron)	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

aileron-wing-segment

aileron: wing segment 200 mm chord × 300 mm, 20 % chord surface deflected 20°

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Plain text: sheet.txt · JSON: /api/geometry?object=aileron