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WIG hulls: steps, hydrofoils and hydroskis

How do WIG craft get off the water? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: wig hull, ekranoplan hull step, wig hydrofoil, hydroski, wig takeoff from water, ground effect boat hull, stepped hull wig, rc ekranoplan hull, wig sponsons

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

sizes
5 in table

Notes

  • WIG craft must break free of water drag before flying. Designs used hull steps (m-Sky 2), front and stern hydrofoils to soften water landing (Lippisch X-114), bow hydroskis for pitch stability (Lockheed 1963) and aft ski structures to trim take-off and landing (Douglas DAW-S) (Rozhdestvensky).
  • Weiland proposed hydroskis as an alternative to power augmentation, and the Hoverwing HW20 used a static air cushion with retractable skirts only for take-off (Rozhdestvensky). KM operated in waves up to 3 m at take-off (Rozhdestvensky).
  • Used on: Lippisch X-114, m-Sky 2, Douglas DAW-S, Hoverwing HW20.
  • 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.

WIG hulls: steps, hydrofoils and hydroskis size chart

parametervalue or rangesource
Lippisch X-114two front hydrofoils + one sternRozhdestvensky 2006
Lockheed wingship studyV-shaped landing hydrofoil, 4.64 m spanRozhdestvensky 2006
m-Sky 2step on centre-body bottomRozhdestvensky 2006
KM take-off wave heightup to 3 mRozhdestvensky 2006
Hoverwing HW20static cushion, retractable skirts for take-offRozhdestvensky 2006

Where the files are

Other publishers' files are linked, not hosted. "verify" = check the license at the link before commercial use.

Progress in Aerospace Sciences (K.V. Rozhdestvensky, 2006)Wing-in-ground effect vehicles (review)webPublisher's page; dimensions are facts

Free files

★ Free files 1 parts. Xem Studio design: free to use, print and sell things from; not to be republished as files. Xem Studio Design License. index.json

wig-hull-steps-hydrofoils-hullstepped hull, 600 × 150 mm, deadrise 20°, 1 steps (sections illustrative, scale to your boat)STEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=wig-hull-steps-hydrofoils

WIG hulls: steps, hydrofoils and hydroskis, isometric render of a generated part
Render of wig-hull-steps-hydrofoils-hull from the free STEP; not to scale.

Fits with

Ground effect: height/span ratio and induced-drag reduction, isometric render of a generated part
Ground effect: height/span ratio and induced-drag reduction6 sizes★ 1 file
Ground effect: height/chord ratio (ram / chord-dominated regime), isometric render of a generated part
Ground effect: height/chord ratio (ram / chord-dominated regime)7 sizes★ 1 file
Lippisch reverse-delta ground-effect craft, isometric render of a generated part
Lippisch reverse-delta ground-effect craft7 sizes★ 1 file
Ekranoplan layout (low wing + high tailplane out of ground effect), isometric render of a generated part
Ekranoplan layout (low wing + high tailplane out of ground effect)6 sizes★ 1 file
Tandem-wing ground-effect craft (Jorg type), isometric render of a generated part
Tandem-wing ground-effect craft (Jorg type)3 sizes★ 1 file
Power-augmented ram (PAR), isometric render of a generated part
Power-augmented ram (PAR)8 sizes★ 1 file

Questions

What hull helps a WIG model unstick?

A stepped hull or hydrofoils/hydroskis, all used on full-size craft (Rozhdestvensky).