# Ekranoplan layout (low wing + high tailplane out of ground effect)

> How is a Soviet ekranoplan laid out?

- Category: Aircraft design › Ground-effect design
- Kind: Standard part
- Basis: Design rules and figures from the cited sources; example geometry by Xem Studio
- Page: https://xemstudio.com/objects/ekranoplan-wing-tail-layout/ · JSON: https://xemstudio.com/api/geometry?object=ekranoplan-wing-tail-layout · Plain text: https://xemstudio.com/objects/ekranoplan-wing-tail-layout/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files Xem Studio Design License (free to use and sell from, not to redistribute as files: https://xemstudio.com/license/)
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

**Exact dimensions.** True size, with no printing tolerance added.

## 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.

## Sizes

| parameter | value or range | source |
|---|---|---|
| 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) |

## Where the files are

- Progress in Aerospace Sciences (K.V. Rozhdestvensky, 2006): [Wing-in-ground effect vehicles (review)](https://www.hassanhameed.com/wp-content/uploads/2016/01/wingingroundeffectvehicles-130120003005-phpapp01.pdf) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, Xem Studio Design License, Xem Studio)

Index: https://xemstudio.com/files/hardware/ekranoplan-wing-tail-layout/index.json · license: https://xemstudio.com/files/hardware/ekranoplan-wing-tail-layout/LICENSE.md

- ekranoplan-wing-tail-layout-wing: [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) — ekranoplan tandem: span 600, chord 300 mm, anhedral 0°, endplates 40 mm (scale to your craft)

## Questions

**Why is the ekranoplan tail so big and high?**

It must stay outside ground effect to give stable pitch reference; the KM's was up to 50% of wing area (Rozhdestvensky).

## Fits with

- [Ground effect: height/span ratio and induced-drag reduction](https://xemstudio.com/objects/ground-effect-height-span-ratio/)
- [Ground effect: height/chord ratio (ram / chord-dominated regime)](https://xemstudio.com/objects/ground-effect-height-chord-ratio/)
- [Lippisch reverse-delta ground-effect craft](https://xemstudio.com/objects/lippisch-reverse-delta-wig/)
- [Tandem-wing ground-effect craft (Jorg type)](https://xemstudio.com/objects/tandem-wig-configuration/)
- [Power-augmented ram (PAR)](https://xemstudio.com/objects/power-augmented-ram-par/)
- [Endplates on ground-effect wings](https://xemstudio.com/objects/wig-endplates/)