{
 "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": "ekranoplan-wing-tail-layout",
 "name": "Ekranoplan layout (low wing + high tailplane out of ground effect)",
 "kind": "standard",
 "category": "Aircraft design",
 "group": "Ground-effect design",
 "year": null,
 "question": "How is a Soviet ekranoplan laid out?",
 "tags": [
  "vehicle design",
  "ground-effect design",
  "rc design",
  "aerodynamics"
 ],
 "aliases": [
  "ekranoplan",
  "caspian sea monster",
  "ekranoplan design",
  "km ekranoplan",
  "lun ekranoplan",
  "orlyonok",
  "ekranoplan rc model",
  "ekranoplan tail",
  "soviet ground effect vehicle",
  "wig airplane type"
 ],
 "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/ekranoplan-wing-tail-layout/",
 "sheet_txt": "https://xemstudio.com/objects/ekranoplan-wing-tail-layout/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 airplane-type ekranoplan pairs a low-AR main wing in ground effect with a high tailplane kept outside ground influence; the KM's tail area reached up to 50% of the wing's, reduced to 27% on the MPE-400 using S-shaped central sections (Rozhdestvensky).",
   "The KM (Caspian Sea Monster) had 550 t take-off weight, length over 90 m, AR 2 and cruise above 500 km/h, using eight 10 t forward engines for PAR take-off and two for cruise (Rozhdestvensky).",
   "Orlyonok (120 t, AR 3) and Loon (400 t, 74 m, AR above 3) followed the same layout (Rozhdestvensky).",
   "Used on: KM (Caspian Sea Monster), Orlyonok, Loon, MPE-400.",
   "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": [
    [
     "KM tail area / wing area",
     "up to 50%",
     "Rozhdestvensky 2006"
    ],
    [
     "MPE-400 tail / wing",
     "27%",
     "Rozhdestvensky 2006"
    ],
    [
     "KM: TOW / length / AR / cruise",
     "550 t / >90 m / 2 / >500 km/h",
     "Rozhdestvensky 2006"
    ],
    [
     "Orlyonok: TOW / length / AR",
     "120 t / 60 m / 3",
     "Rozhdestvensky 2006"
    ],
    [
     "Loon: TOW / length / cruise",
     "400 t / 74 m / 450 km/h",
     "Rozhdestvensky 2006"
    ],
    [
     "Reference build",
     "span 600, root 300 (AR 2), endplates 40",
     "computed (KM AR)"
    ]
   ]
  }
 },
 "sheet_text": "Ekranoplan layout (low wing + high tailplane out of ground effect) — dimension sheet\nSource: Xem Studio, https://xemstudio.com/objects/ekranoplan-wing-tail-layout/  (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- The airplane-type ekranoplan pairs a low-AR main wing in ground effect with a high tailplane kept outside ground influence; the KM's tail area reached up to 50% of the wing's, reduced to 27% on the MPE-400 using S-shaped central sections (Rozhdestvensky).\n- The KM (Caspian Sea Monster) had 550 t take-off weight, length over 90 m, AR 2 and cruise above 500 km/h, using eight 10 t forward engines for PAR take-off and two for cruise (Rozhdestvensky).\n- Orlyonok (120 t, AR 3) and Loon (400 t, 74 m, AR above 3) followed the same layout (Rozhdestvensky).\n- Used on: KM (Caspian Sea Monster), Orlyonok, Loon, MPE-400.\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\nKM tail area / wing area  up to 50%  Rozhdestvensky 2006\nMPE-400 tail / wing  27%  Rozhdestvensky 2006\nKM: TOW / length / AR / cruise  550 t / >90 m / 2 / >500 km/h  Rozhdestvensky 2006\nOrlyonok: TOW / length / AR  120 t / 60 m / 3  Rozhdestvensky 2006\nLoon: TOW / length / cruise  400 t / 74 m / 450 km/h  Rozhdestvensky 2006\nReference build  span 600, root 300 (AR 2), endplates 40  computed (KM AR)\n\nFiles elsewhere (not hosted by Xem Studio; license as stated by the publisher):\n- Progress in Aerospace Sciences (K.V. Rozhdestvensky, 2006): Wing-in-ground effect vehicles (review) — web — Publisher's page; dimensions are facts — https://www.hassanhameed.com/wp-content/uploads/2016/01/wingingroundeffectvehicles-130120003005-phpapp01.pdf\n\nFree files (Xem Studio Design License, Xem Studio; STEP + STL, 1 parts): https://xemstudio.com/files/hardware/ekranoplan-wing-tail-layout/index.json\nAPI: https://xemstudio.com/api/geometry?object=ekranoplan-wing-tail-layout\n",
 "sources": [
  {
   "publisher": "Progress in Aerospace Sciences (K.V. Rozhdestvensky, 2006)",
   "title": "Wing-in-ground effect vehicles (review)",
   "url": "https://www.hassanhameed.com/wp-content/uploads/2016/01/wingingroundeffectvehicles-130120003005-phpapp01.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": [
  "ground-effect-height-span-ratio",
  "ground-effect-height-chord-ratio",
  "lippisch-reverse-delta-wig",
  "tandem-wig-configuration",
  "power-augmented-ram-par",
  "wig-endplates"
 ],
 "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": "Why is the ekranoplan tail so big and high?",
   "a": "It must stay outside ground effect to give stable pitch reference; the KM's was up to 50% of wing area (Rozhdestvensky)."
  }
 ],
 "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": "ekranoplan-wing-tail-layout-wing",
   "formats": [
    "step",
    "stl"
   ],
   "price_usd": 0,
   "license": "Xem Studio Design License",
   "step": "https://xemstudio.com/files/hardware/ekranoplan-wing-tail-layout/ekranoplan-wing-tail-layout-wing.step",
   "stl": "https://xemstudio.com/files/hardware/ekranoplan-wing-tail-layout/ekranoplan-wing-tail-layout-wing.stl",
   "note": "ekranoplan tandem: span 600, chord 300 mm, anhedral 0°, endplates 40 mm (scale to your craft)"
  }
 ],
 "markdown": "https://xemstudio.com/objects/ekranoplan-wing-tail-layout/index.md"
}