{
 "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": "eppler-e387-airfoil",
 "name": "Eppler E387 airfoil",
 "kind": "standard",
 "category": "Airfoils",
 "group": "Airfoils",
 "year": null,
 "question": "Why is the Eppler 387 a benchmark airfoil?",
 "tags": [
  "vehicle design",
  "airfoils",
  "rc design",
  "aerodynamics",
  "guide"
 ],
 "aliases": [
  "e387",
  "eppler 387",
  "eppler e387 airfoil",
  "e387 coordinates",
  "e387 dat",
  "low reynolds airfoil benchmark",
  "e387 rc glider",
  "eppler airfoil",
  "laminar separation bubble airfoil"
 ],
 "overall_mm": {
  "length": null,
  "width": null,
  "height": null
 },
 "official_cad": false,
 "xem_status": "not-scanned",
 "les": false,
 "free_files": 0,
 "url": "https://xemstudio.com/objects/eppler-e387-airfoil/",
 "sheet_txt": "https://xemstudio.com/objects/eppler-e387-airfoil/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": [
   "The Eppler 387 was tested by NASA Langley in the Low-Turbulence Pressure Tunnel at chord Reynolds numbers from 60,000 to 460,000 (NASA TM-4062), making it a standard benchmark for low-Re (model-aircraft) airfoil behaviour.",
   "The NASA tests used oil-flow visualisation to locate laminar separation and turbulent reattachment, the laminar bubble that dominates model-scale airfoil drag (NASA TM-4062)."
  ],
  "table": {
   "columns": [
    "parameter",
    "value or range",
    "source"
   ],
   "rows": [
    [
     "NASA test Re range",
     "60,000-460,000",
     "NASA TM-4062"
    ],
    [
     "NASA test Mach range",
     "0.03-0.13",
     "NASA TM-4062"
    ],
    [
     "Coordinates source",
     "NASA TM-4062",
     "NASA TM-4062"
    ]
   ]
  }
 },
 "sheet_text": "Eppler E387 airfoil — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/eppler-e387-airfoil/  (sheet CC BY 4.0)\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- The Eppler 387 was tested by NASA Langley in the Low-Turbulence Pressure Tunnel at chord Reynolds numbers from 60,000 to 460,000 (NASA TM-4062), making it a standard benchmark for low-Re (model-aircraft) airfoil behaviour.\n- The NASA tests used oil-flow visualisation to locate laminar separation and turbulent reattachment, the laminar bubble that dominates model-scale airfoil drag (NASA TM-4062).\n\nparameter  value or range  source\nNASA test Re range  60,000-460,000  NASA TM-4062\nNASA test Mach range  0.03-0.13  NASA TM-4062\nCoordinates source  NASA TM-4062  NASA TM-4062\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- NASA Langley (McGhee, Walker & Millard): Experimental Results for the Eppler 387 Airfoil at Low Reynolds Numbers in the LTPT, NASA TM-4062 (1988) — web — Publisher's page; dimensions are facts — https://ntrs.nasa.gov/citations/19890001471\n\nNo true-size file yet: the published figures do not fix the whole shape; a measured scan is planned.\nAPI: https://xemstudio.com/api/geometry?object=eppler-e387-airfoil\n",
 "sources": [
  {
   "publisher": "NASA Langley (McGhee, Walker & Millard)",
   "title": "Experimental Results for the Eppler 387 Airfoil at Low Reynolds Numbers in the LTPT, NASA TM-4062 (1988)",
   "url": "https://ntrs.nasa.gov/citations/19890001471",
   "formats": [
    "web"
   ],
   "license": "Publisher's page; dimensions are facts",
   "license_verified": true,
   "hosted": false
  }
 ],
 "xem": {
  "status": "not-scanned",
  "sheet_free": true,
  "mesh_price_usd": null,
  "step_price_usd": null,
  "tolerance_mm": null
 },
 "related": [
  "clark-y-airfoil",
  "selig-s1223-airfoil",
  "mh32-airfoil",
  "ag35-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": "What Reynolds numbers does E387 data cover?",
   "a": "NASA's LTPT tests ran 60,000 to 460,000 (TM-4062)."
  }
 ],
 "files_license": null,
 "offers": [],
 "markdown": "https://xemstudio.com/objects/eppler-e387-airfoil/index.md"
}