{
 "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-6409-airfoil",
 "name": "NACA 6409 airfoil",
 "kind": "standard",
 "category": "Airfoils",
 "group": "NACA 4-digit",
 "year": null,
 "question": "What is the exact shape of the NACA 6409 airfoil, and what do the digits mean?",
 "tags": [
  "airfoil",
  "naca",
  "wing section",
  "rc plane",
  "aerodynamics",
  "cambered airfoil"
 ],
 "aliases": [
  "NACA 6409",
  "NACA 6409 airfoil",
  "NACA 6409 coordinates",
  "NACA 6409 dat",
  "NACA 6409 profile",
  "NACA 6409 DXF",
  "NACA 6409 STEP",
  "NACA 6409 STL",
  "perfil NACA 6409",
  "Profil NACA 6409",
  "naca6409",
  "NACA 6409 wing section"
 ],
 "overall_mm": {
  "length": 100,
  "width": 20,
  "height": 8.98
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/naca-6409-airfoil/",
 "sheet_txt": "https://xemstudio.com/objects/naca-6409-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": 8.98
  },
  "notes": [
   "NACA 6409: 6 % camber at 40 % chord, 9 % thick.",
   "NACA 4-digit: first digit = maximum camber in % of chord, second = its position in tenths of chord, last two = maximum thickness in % of chord (NACA Report 460).",
   "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",
     "0.854",
     "1.733",
     "1.646",
     "-0.995"
    ],
    [
     "2.5",
     "1.969",
     "2.614",
     "3.031",
     "-1.161"
    ],
    [
     "5",
     "4.323",
     "3.985",
     "5.677",
     "-1.172"
    ],
    [
     "7.5",
     "6.754",
     "5.099",
     "8.246",
     "-1.021"
    ],
    [
     "10",
     "9.229",
     "6.051",
     "10.771",
     "-0.801"
    ],
    [
     "15",
     "14.261",
     "7.596",
     "15.739",
     "-0.284"
    ],
    [
     "20",
     "19.362",
     "8.755",
     "20.638",
     "0.245"
    ],
    [
     "25",
     "24.502",
     "9.584",
     "25.498",
     "0.729"
    ],
    [
     "30",
     "29.663",
     "10.113",
     "30.337",
     "1.137"
    ],
    [
     "40",
     "40.000",
     "10.350",
     "40.000",
     "1.650"
    ],
    [
     "50",
     "50.132",
     "9.796",
     "49.868",
     "1.871"
    ],
    [
     "60",
     "60.227",
     "8.736",
     "59.773",
     "1.931"
    ],
    [
     "70",
     "70.271",
     "7.212",
     "69.729",
     "1.788"
    ],
    [
     "80",
     "80.255",
     "5.245",
     "79.745",
     "1.422"
    ],
    [
     "90",
     "90.168",
     "2.843",
     "89.832",
     "0.823"
    ],
    [
     "95",
     "95.095",
     "1.478",
     "94.905",
     "0.439"
    ],
    [
     "100",
     "100.000",
     "-0.000",
     "100.000",
     "0.000"
    ]
   ]
  }
 },
 "sheet_text": "NACA 6409 airfoil — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/naca-6409-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 8.98\n- NACA 6409: 6 % camber at 40 % chord, 9 % thick.\n- NACA 4-digit: first digit = maximum camber in % of chord, second = its position in tenths of chord, last two = maximum thickness in % of chord (NACA Report 460).\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  0.854  1.733  1.646  -0.995\n2.5  1.969  2.614  3.031  -1.161\n5  4.323  3.985  5.677  -1.172\n7.5  6.754  5.099  8.246  -1.021\n10  9.229  6.051  10.771  -0.801\n15  14.261  7.596  15.739  -0.284\n20  19.362  8.755  20.638  0.245\n25  24.502  9.584  25.498  0.729\n30  29.663  10.113  30.337  1.137\n40  40.000  10.350  40.000  1.650\n50  50.132  9.796  49.868  1.871\n60  60.227  8.736  59.773  1.931\n70  70.271  7.212  69.729  1.788\n80  80.255  5.245  79.745  1.422\n90  90.168  2.843  89.832  0.823\n95  95.095  1.478  94.905  0.439\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-6409-airfoil/index.json\nAPI: https://xemstudio.com/api/geometry?object=naca-6409-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-6412-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 6409?",
   "a": "Maximum thickness 8.98 % of chord at 30.6 % chord: 8.98 mm on a 100 mm chord."
  },
  {
   "q": "Where is the NACA 6409's camber?",
   "a": "Maximum camber 6.00 % of chord at 40.0 % 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-6409-airfoil-section-100mm-chord",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/naca-6409-airfoil/naca-6409-airfoil-section-100mm-chord.step",
   "stl": "https://xemstudio.com/files/hardware/naca-6409-airfoil/naca-6409-airfoil-section-100mm-chord.stl",
   "note": "NACA 6409 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-6409-airfoil/index.md"
}