# Alexeyev SM-5 ekranoplan (1/4-scale KM test craft)

> What are the dimensions of the Alexeyev SM-5 ekranoplan?

- Category: Ground-effect craft › Soviet experimental and scale prototypes
- Kind: Modern device
- Basis: Secondary source: Old Machine Press (copy of the maker's figures; the maker publishes none directly)
- Page: https://xemstudio.com/objects/alexeyev-sm-5-ekranoplan/ · JSON: https://xemstudio.com/api/geometry?object=alexeyev-sm-5-ekranoplan · Plain text: https://xemstudio.com/objects/alexeyev-sm-5-ekranoplan/sheet.txt
- License: dimension sheet CC BY 4.0 (Xem Studio); files CC BY 4.0 or their publisher's license
- Use in every chat: add https://xemstudio.com/mcp as a connector (https://xemstudio.com/use-with-ai/)

## Overall (mm)

| length | width | height |
|---|---|---|
| 18000 | 9500 | 5500 |

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

## Notes

- The SM-5 was a quarter-scale manned model of the KM used to prove the configuration before the full-size craft flew; it was lost in a 1964 accident.
- The file is an 18.0 × 9.5 × 5.5 m box from Old Machine Press. Wing area is not published.
- Marked secondary (magazine-style history site).
- True size, no printing tolerance added. Only published numbers are used; anything not published is said so.
- Secondary source: the numbers come from a retailer or magazine copy of the maker's specification.

## Sizes

| dimension | value |
|---|---|
| Length | 18.0 m (59 ft 1 in) |
| Wingspan | 9.5 m (31 ft 2 in) |
| Height | 5.5 m (18 ft 1 in) |
| Maximum weight | 7,300 kg (16,094 lb) |
| Engines | 2 × Mikulin KR7-300 jet engines |
| Ground-effect flying height | 1–3 m (3–10 ft) |
| Role | 25% scale aerodynamic test craft for the KM |

## Where the files are

- Old Machine Press: [Alexeyev KM Ekranoplan – Caspian Sea Monster (SM-5 section)](https://oldmachinepress.com/2019/11/05/alexeyev-km-ekranoplan-caspian-sea-monster/) — web — Publisher's page; dimensions are facts

## Free STEP/STL (1 parts, CC BY 4.0, Xem Studio)

Index: https://xemstudio.com/files/hardware/alexeyev-sm-5-ekranoplan/index.json

- alexeyev-sm-5-ekranoplan-envelope: [STEP](https://xemstudio.com/files/hardware/alexeyev-sm-5-ekranoplan/alexeyev-sm-5-ekranoplan-envelope.step) · [STL](https://xemstudio.com/files/hardware/alexeyev-sm-5-ekranoplan/alexeyev-sm-5-ekranoplan-envelope.stl) — Envelope 18000 × 9500 × 5500 mm (Real craft: overall length × wingspan × overall height as published)

## Questions

**How big was the SM-5?**

18.0 m long, 9.5 m wingspan and 5.5 m high, with a 7,300 kg maximum weight.

## Fits with

- [Alexeyev SM-8 ekranoplan (second 1/4-scale KM test craft)](https://xemstudio.com/objects/alexeyev-sm-8-ekranoplan/)
- [Bartini Beriev VVA-14 (14M1P ground-effect amphibian)](https://xemstudio.com/objects/bartini-beriev-vva-14/)
- [Grunin ESKA-1 experimental ekranoplan (2-seat)](https://xemstudio.com/objects/grunin-eska-1-ekranoplan/)