Washout (wing twist) — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/washout-wing-twist/  (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
- Washout twists the wing so the tip is at a lower incidence than the root; it keeps the root stalling first so ailerons keep working (Boldmethod) and lets tip and root reach their angle of attack together on swept wings (R/C Soaring Digest).
- Leishman gives typical washout between 0 and 10 deg nose-down, more being unusual; washin (tip nose-up) appears on the X-29's forward-swept wing (ERAU).
- Twist can also tune the span loading toward elliptical (Kitplanes).
- Used on: X-29 (washin).
- 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.

parameter  value or range  source
Typical washout  0-10 deg nose-down  ERAU (Leishman)
Washin example  X-29 forward-swept wing  ERAU
Historic wing-warp turn trim (models)  about 1-3 deg tip washin  McCombs 1992
Reference build  tapered 0.45 wing (twist parameter not in builder)  illustrative

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- Embry-Riddle (Leishman), Introduction to Aerospace Flight Vehicles: Wing Shapes and Nomenclature — web — Publisher's page; dimensions are facts — https://eaglepubs.erau.edu/introductiontoaerospaceflightvehicles/chapter/wing-shapes-and-nomenclature/
- Boldmethod (pilot training): How Stall Strips Keep Your Plane Under Control — web — Publisher's page; dimensions are facts — https://www.boldmethod.com/learn-to-fly/aerodynamics/how-stall-strips-keep-your-plane-under-control/
- R/C Soaring Digest: Twist Distributions for Swept Wings, Part 2 (June 2002) — web — Publisher's page; dimensions are facts — https://new.rcsoaringdigest.com/2002/06/twist-distributions-for-swept-wings/[pdf].pdf
- Kitplanes (B. Wainfan): Design Process: Planform Effects on Span Loading and Drag (2020) — web — Publisher's page; dimensions are facts — https://www.kitplanes.com/design-process-planform-effects-on-span-loading-and-drag/
- Model Aviation (AMA), W.F. McCombs: Vertical Tail Size for Models (Apr 1992) — web — Publisher's page; dimensions are facts — https://library.modelaviation.com/article/vertical-tail-size-models-1

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