Selig S3021 airfoil — dimension sheet
Source: Xem Studio, https://xemstudio.com/objects/s3021-airfoil/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)
Basis: Coordinates from the UIUC Airfoil Coordinates Database; thickness, camber and section by Xem Studio
Catalog version: 2026-10-20

Overall (mm): length 100.0, width 20.0, height 9.47
- Selig S3021: Michael Selig (S series). Maximum thickness 9.47 % of chord at 30.0 % chord; maximum camber 2.96 % of chord at 39.2 % chord.
- Coordinates from the UIUC Airfoil Coordinates Database (M. Selig, UIUC Applied Aerodynamics Group), file s3021.dat, titled 'S3021-095-84'. Thickness and camber are computed by Xem Studio from those points (vertical distance at equal x, linear between points).
- The published trailing edge is sharp, so the section uses it as printed.
- The file is a 100 mm chord section, 20 mm deep: scale it uniformly to your chord, or import the STEP and sweep or loft it into a wing. Thickness scales with chord; the shape is the same at any size.

parameter  value  source
Max thickness  9.47 % chord at 30.0 % chord  computed from the UIUC coordinates
Max camber  2.96 % chord at 39.2 % chord  computed from the UIUC coordinates
Published points  61 (32 upper, 30 lower, shared leading edge)  UIUC coordinates
Trailing edge as published  sharp (closed)  UIUC coordinates
y at x = 1.25 % chord  upper +1.679 / lower -0.928 % chord  linear between the published points (UIUC coordinates)
y at x = 2.5 % chord  upper +2.548 / lower -1.263 % chord  linear between the published points (UIUC coordinates)
y at x = 5 % chord  upper +3.753 / lower -1.631 % chord  linear between the published points (UIUC coordinates)
y at x = 7.5 % chord  upper +4.643 / lower -1.845 % chord  linear between the published points (UIUC coordinates)
y at x = 10 % chord  upper +5.334 / lower -1.975 % chord  linear between the published points (UIUC coordinates)
y at x = 15 % chord  upper +6.341 / lower -2.073 % chord  linear between the published points (UIUC coordinates)
y at x = 20 % chord  upper +6.982 / lower -2.063 % chord  linear between the published points (UIUC coordinates)
y at x = 25 % chord  upper +7.386 / lower -1.988 % chord  linear between the published points (UIUC coordinates)
y at x = 30 % chord  upper +7.596 / lower -1.874 % chord  linear between the published points (UIUC coordinates)
y at x = 40 % chord  upper +7.498 / lower -1.599 % chord  linear between the published points (UIUC coordinates)
y at x = 50 % chord  upper +6.861 / lower -1.304 % chord  linear between the published points (UIUC coordinates)
y at x = 60 % chord  upper +5.805 / lower -1.015 % chord  linear between the published points (UIUC coordinates)
y at x = 70 % chord  upper +4.494 / lower -0.744 % chord  linear between the published points (UIUC coordinates)
y at x = 80 % chord  upper +3.063 / lower -0.493 % chord  linear between the published points (UIUC coordinates)
y at x = 90 % chord  upper +1.567 / lower -0.251 % chord  linear between the published points (UIUC coordinates)
y at x = 95 % chord  upper +0.768 / lower -0.103 % chord  linear between the published points (UIUC coordinates)
Coordinates source  UIUC Airfoil Coordinates Database: s3021.dat ('S3021-095-84')  UIUC Applied Aerodynamics Group (M. Selig)

Files elsewhere (not hosted by Xem Studio; license as stated by the publisher):
- UIUC Applied Aerodynamics Group (M. Selig): UIUC Airfoil Coordinates Database: s3021.dat ('S3021-095-84') — web — UIUC Airfoil Coordinates Database, public research data; coordinates are facts, cited and linked, not rehosted — https://m-selig.ae.illinois.edu/ads/coord/s3021.dat
- UIUC Applied Aerodynamics Group (M. Selig): UIUC Airfoil Coordinates Database (original: Michael Selig (S series)) — web — UIUC Airfoil Coordinates Database, public research data; coordinates are facts, cited and linked, not rehosted — https://m-selig.ae.illinois.edu/ads/coord_database.html

Free files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/s3021-airfoil/index.json
API: https://xemstudio.com/api/geometry?object=s3021-airfoil