{
 "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": "vortex-generators",
 "name": "Vortex generators",
 "kind": "standard",
 "category": "Aircraft design",
 "group": "Wing features",
 "year": null,
 "question": "How do you size and place vortex generators?",
 "tags": [
  "vehicle design",
  "wing features",
  "rc design",
  "aerodynamics"
 ],
 "aliases": [
  "vortex generators",
  "vg wing",
  "vortex generator spacing",
  "vortex generator height",
  "vortex generators rc plane",
  "vg kit stol",
  "vortex generator angle",
  "boundary layer energizer",
  "how vortex generators work",
  "co-rotating vortex generators"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "free-files",
 "les": false,
 "free_files": 1,
 "url": "https://xemstudio.com/objects/vortex-generators/",
 "sheet_txt": "https://xemstudio.com/objects/vortex-generators/sheet.txt",
 "sheet": {
  "basis": "Design rules and figures from the cited sources; example geometry by Xem Studio",
  "overall_mm": {
   "length": null,
   "width": null,
   "height": null
  },
  "notes": [
   "Vortex generators are small vanes that stir high-energy air into the boundary layer to delay separation; full-span VGs reduce stall speed, outboard-only VGs mainly improve stall behaviour and aileron control (Kitplanes, Wainfan).",
   "First-try height is about 1.2x local boundary-layer thickness (roughly 1-2% of distance from the leading edge), at 15-20 deg to the flow, slightly upstream of the natural separation point (Kitplanes).",
   "Drag can be significant on laminar wings (Kitplanes); on the S1223 airfoil VGs caused an abrupt stall with hysteresis between 16 and 20 deg (Selig & Guglielmo).",
   "Used on: Beech Baron (retrofit), Rutan Voyager, Beech Starship, Boeing 727 fin.",
   "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."
  ],
  "table": {
   "columns": [
    "parameter",
    "value or range",
    "source"
   ],
   "rows": [
    [
     "Height",
     "~1.2 x boundary-layer thickness",
     "Kitplanes (Wainfan)"
    ],
    [
     "Boundary layer thickness",
     "~1-2% of distance from LE",
     "Kitplanes"
    ],
    [
     "Angle to flow",
     "15-20 deg",
     "Kitplanes"
    ],
    [
     "Co-rotating: root chord / spacing",
     "~4h / 5-6h",
     "Kitplanes"
    ],
    [
     "Counter-rotating: root chord / pair spacing",
     "~2.5h / ~10h between pairs",
     "Kitplanes"
    ],
    [
     "Reference build",
     "chord 100, VG at 20 deg",
     "Kitplanes"
    ]
   ]
  }
 },
 "sheet_text": "Vortex generators — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/vortex-generators/  (sheet CC BY 4.0; files Xem Studio Design License, https://xemstudio.com/license/)\nBasis: Design rules and figures from the cited sources; example geometry by Xem Studio\nCatalog version: 2026-10-20\n\nSizes: see table below\n- Vortex generators are small vanes that stir high-energy air into the boundary layer to delay separation; full-span VGs reduce stall speed, outboard-only VGs mainly improve stall behaviour and aileron control (Kitplanes, Wainfan).\n- First-try height is about 1.2x local boundary-layer thickness (roughly 1-2% of distance from the leading edge), at 15-20 deg to the flow, slightly upstream of the natural separation point (Kitplanes).\n- Drag can be significant on laminar wings (Kitplanes); on the S1223 airfoil VGs caused an abrupt stall with hysteresis between 16 and 20 deg (Selig & Guglielmo).\n- Used on: Beech Baron (retrofit), Rutan Voyager, Beech Starship, Boeing 727 fin.\n- 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.\n\nparameter  value or range  source\nHeight  ~1.2 x boundary-layer thickness  Kitplanes (Wainfan)\nBoundary layer thickness  ~1-2% of distance from LE  Kitplanes\nAngle to flow  15-20 deg  Kitplanes\nCo-rotating: root chord / spacing  ~4h / 5-6h  Kitplanes\nCounter-rotating: root chord / pair spacing  ~2.5h / ~10h between pairs  Kitplanes\nReference build  chord 100, VG at 20 deg  Kitplanes\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Kitplanes (B. Wainfan): Wind Tunnel: Vortex Generators and STOL Performance (2012) — web — Publisher's page; dimensions are facts — https://www.kitplanes.com/wind-tunnel-14/\n- University of Illinois (Selig & Guglielmo), Journal of Aircraft 1997: High-Lift Low Reynolds Number Airfoil Design (S1223) — web — Publisher's page; dimensions are facts — https://m-selig.web.engr.illinois.edu/pubs/GuglielmoSelig-1997-JofAC-S1223.pdf\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/vortex-generators/index.json\nAPI: https://xemstudio.com/api/geometry?object=vortex-generators\n",
 "sources": [
  {
   "publisher": "Kitplanes (B. Wainfan)",
   "title": "Wind Tunnel: Vortex Generators and STOL Performance (2012)",
   "url": "https://www.kitplanes.com/wind-tunnel-14/",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  },
  {
   "publisher": "University of Illinois (Selig & Guglielmo), Journal of Aircraft 1997",
   "title": "High-Lift Low Reynolds Number Airfoil Design (S1223)",
   "url": "https://m-selig.web.engr.illinois.edu/pubs/GuglielmoSelig-1997-JofAC-S1223.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": [
  "plain-flap",
  "split-flap",
  "slotted-flap",
  "fowler-flap",
  "leading-edge-slat-slot",
  "gurney-flap"
 ],
 "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": "Where do VGs go on the chord?",
   "a": "Just ahead of where the flow would naturally separate (Kitplanes)."
  }
 ],
 "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": "vortex-generators-wing-segment",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/vortex-generators/vortex-generators-wing-segment.step",
   "stl": "https://xemstudio.com/files/hardware/vortex-generators/vortex-generators-wing-segment.stl",
   "note": "Wing segment, NACA 2412 100 mm chord, with a row of vortex generators at 25 % chord (illustrative size)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/vortex-generators/index.md"
}