{
 "version": "2026-10-20",
 "license": "Dimension sheets: CC BY 4.0. Standard and published-size files: CC BY 4.0. Xem Studio's own designs (files_license = Xem Studio Design License): free to use and sell things from, not to redistribute as files — https://xemstudio.com/license/. Other publishers' files: their own license, linked beside them.",
 "slug": "naca-23021-airfoil",
 "name": "NACA 23021 airfoil",
 "kind": "standard",
 "category": "Airfoils",
 "group": "NACA 5-digit",
 "year": null,
 "question": "What is the exact shape of the NACA 23021 airfoil, and what do the digits mean?",
 "tags": [
  "airfoil",
  "naca",
  "wing section",
  "rc plane",
  "aerodynamics",
  "cambered airfoil"
 ],
 "aliases": [
  "NACA 23021",
  "NACA 23021 airfoil",
  "NACA 23021 coordinates",
  "NACA 23021 dat",
  "NACA 23021 profile",
  "NACA 23021 DXF",
  "NACA 23021 STEP",
  "NACA 23021 STL",
  "perfil NACA 23021",
  "Profil NACA 23021",
  "naca23021",
  "NACA 23021 wing section"
 ],
 "overall_mm": {
  "length": 100,
  "width": 20,
  "height": 21
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/naca-23021-airfoil/",
 "sheet_txt": "https://xemstudio.com/objects/naca-23021-airfoil/sheet.txt",
 "sheet": {
  "basis": "Computed from the NACA equations (Report 460 / Report 610, restated in NASA TM-4741)",
  "overall_mm": {
   "length": 100,
   "width": 20,
   "height": 21
  },
  "notes": [
   "NACA 23021: 5-digit 230 mean line (design lift coefficient 0.3, camber peak at 15 % chord), 21 % thick.",
   "NACA 5-digit 230xx: '2' × 3/2 = design lift coefficient 0.3; '30' = camber peak at 15 % chord on a simple mean line; last two digits = maximum thickness in % of chord (NACA Report 610; TM-4741).",
   "Ordinates are in % of chord from the leading edge, computed from the published equations with the closed-trailing-edge thickness coefficient (−0.1036, as in NASA TM-4741). The original reports use an open trailing edge (−0.1015); the difference is under 0.03 % of chord near the trailing edge.",
   "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."
  ],
  "table": {
   "columns": [
    "x (% chord)",
    "upper x",
    "upper y",
    "lower x",
    "lower y"
   ],
   "rows": [
    [
     "0",
     "0.000",
     "0.000",
     "0.000",
     "0.000"
    ],
    [
     "1.25",
     "0.398",
     "3.560",
     "2.102",
     "-2.846"
    ],
    [
     "2.5",
     "1.477",
     "5.126",
     "3.523",
     "-3.794"
    ],
    [
     "5",
     "3.996",
     "7.294",
     "6.004",
     "-4.984"
    ],
    [
     "7.5",
     "6.714",
     "8.799",
     "8.286",
     "-5.816"
    ],
    [
     "10",
     "9.495",
     "9.880",
     "10.505",
     "-6.478"
    ],
    [
     "15",
     "15.001",
     "11.193",
     "14.999",
     "-7.515"
    ],
    [
     "20",
     "20.221",
     "11.805",
     "19.779",
     "-8.271"
    ],
    [
     "25",
     "25.230",
     "12.050",
     "24.770",
     "-8.737"
    ],
    [
     "30",
     "30.232",
     "12.045",
     "29.768",
     "-8.953"
    ],
    [
     "40",
     "40.224",
     "11.472",
     "39.776",
     "-8.822"
    ],
    [
     "50",
     "50.204",
     "10.353",
     "49.796",
     "-8.144"
    ],
    [
     "60",
     "60.176",
     "8.839",
     "59.824",
     "-7.072"
    ],
    [
     "70",
     "70.140",
     "7.020",
     "69.860",
     "-5.695"
    ],
    [
     "80",
     "80.099",
     "4.941",
     "79.901",
     "-4.057"
    ],
    [
     "90",
     "90.053",
     "2.609",
     "89.947",
     "-2.167"
    ],
    [
     "95",
     "95.027",
     "1.342",
     "94.973",
     "-1.121"
    ],
    [
     "100",
     "100.000",
     "-0.000",
     "100.000",
     "0.000"
    ]
   ]
  }
 },
 "sheet_text": "NACA 23021 airfoil — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/naca-23021-airfoil/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Computed from the NACA equations (Report 460 / Report 610, restated in NASA TM-4741)\nCatalog version: 2026-10-20\n\nOverall (mm): length 100.0, width 20.0, height 21.0\n- NACA 23021: 5-digit 230 mean line (design lift coefficient 0.3, camber peak at 15 % chord), 21 % thick.\n- NACA 5-digit 230xx: '2' × 3/2 = design lift coefficient 0.3; '30' = camber peak at 15 % chord on a simple mean line; last two digits = maximum thickness in % of chord (NACA Report 610; TM-4741).\n- Ordinates are in % of chord from the leading edge, computed from the published equations with the closed-trailing-edge thickness coefficient (−0.1036, as in NASA TM-4741). The original reports use an open trailing edge (−0.1015); the difference is under 0.03 % of chord near the trailing edge.\n- 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.\n\nx (% chord)  upper x  upper y  lower x  lower y\n0  0.000  0.000  0.000  0.000\n1.25  0.398  3.560  2.102  -2.846\n2.5  1.477  5.126  3.523  -3.794\n5  3.996  7.294  6.004  -4.984\n7.5  6.714  8.799  8.286  -5.816\n10  9.495  9.880  10.505  -6.478\n15  15.001  11.193  14.999  -7.515\n20  20.221  11.805  19.779  -8.271\n25  25.230  12.050  24.770  -8.737\n30  30.232  12.045  29.768  -8.953\n40  40.224  11.472  39.776  -8.822\n50  50.204  10.353  49.796  -8.144\n60  60.176  8.839  59.824  -7.072\n70  70.140  7.020  69.860  -5.695\n80  80.099  4.941  79.901  -4.057\n90  90.053  2.609  89.947  -2.167\n95  95.027  1.342  94.973  -1.121\n100  100.000  -0.000  100.000  0.000\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- NACA (NASA Technical Reports Server): Report 460: The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnel (Jacobs, Ward, Pinkerton, 1933) — web — Publisher's page; dimensions are facts — https://ntrs.nasa.gov/citations/19930091108\n- NASA: TM-4741: Computer program to obtain ordinates for NACA airfoils (Ladson, Brooks, Hill, Sproles, 1996) — web — Publisher's page; dimensions are facts — https://www.pdas.com/refs/tm4741.pdf\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/naca-23021-airfoil/index.json\nAPI: https://xemstudio.com/api/geometry?object=naca-23021-airfoil\n",
 "sources": [
  {
   "publisher": "NACA (NASA Technical Reports Server)",
   "title": "Report 460: The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnel (Jacobs, Ward, Pinkerton, 1933)",
   "url": "https://ntrs.nasa.gov/citations/19930091108",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "NASA",
   "title": "TM-4741: Computer program to obtain ordinates for NACA airfoils (Ladson, Brooks, Hill, Sproles, 1996)",
   "url": "https://www.pdas.com/refs/tm4741.pdf",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "free-files",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "naca-23009-airfoil",
  "naca-23012-airfoil",
  "naca-23015-airfoil",
  "naca-23018-airfoil",
  "naca-23024-airfoil"
 ],
 "fits": [],
 "dimensions": "exact (nominal, no printing tolerance)",
 "dimension_rule": "All geometry on Xem Studio is exact (nominal, true size) with no printing tolerance. Where a part meets another part, the object lists its mating features (feature, exact size, what it mates with, fit class: press, slide, run, socket, clamp or designed). Apply your process's allowance to those features only; 'designed' gaps are part of the design and stay as drawn.",
 "mating": [],
 "faq": [
  {
   "q": "How thick is the NACA 23021?",
   "a": "Maximum thickness 21.00 % of chord at 29.9 % chord: 21.00 mm on a 100 mm chord."
  },
  {
   "q": "Where is the NACA 23021's camber?",
   "a": "Maximum camber 1.84 % of chord at 15.0 % chord."
  },
  {
   "q": "How do I use it for my wing?",
   "a": "Scale the 100 mm section to your chord (e.g. 180 mm chord = 180 % scale), then extrude or loft between root and tip sections. For a tapered wing, scale a root and a tip copy and loft between them."
  }
 ],
 "files_license": {
  "name": "Xem Studio Design License",
  "holder": "Xem Studio",
  "url": "https://xemstudio.com/license/",
  "note": "Xem Studio's own design: free to use, print, modify and sell things made from it; not to be republished or redistributed as files."
 },
 "offers": [
  {
   "file": "naca-23021-airfoil-section-100mm-chord",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/naca-23021-airfoil/naca-23021-airfoil-section-100mm-chord.step",
   "stl": "https://xemstudio.com/files/hardware/naca-23021-airfoil/naca-23021-airfoil-section-100mm-chord.stl",
   "note": "NACA 23021 section, 100 mm chord × 20 mm span, closed trailing edge, 160 points from the equations (scale to your chord)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/naca-23021-airfoil/index.md"
}