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Tandem-wing ground-effect craft (Jorg type)

How do tandem-wing ground-effect craft work? · Standard part · basis: Design rules and figures from the cited sources; example geometry by Xem Studio

Also called: tandem wig, tandem airfoil boat, jorg tab, tandem ground effect, tandem wing ekranoplan, two wing ground effect craft, tandem wig stability, tandem flarecraft

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

sizes
3 in table

Notes

  • The Jorg tandem airfoil boat places two wings in ground effect one behind the other; its stability is 'very sensitive' to the combination of pitch angle and ground clearance (Rozhdestvensky).
  • The 3-ton SM-1 tandem had a high take-off speed and a narrow range of stable heights (Rozhdestvensky). Ground-effect stability needs the aerodynamic centre in height upstream of the centre in pitch (Irodov criterion, Rozhdestvensky).
  • Used on: Jorg TAB, SM-1.
  • 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.

Tandem-wing ground-effect craft size chart

parametervalue or rangesource
SM-1 weight3 tRozhdestvensky 2006
Stabilityvery sensitive to pitch/clearance; narrow stable height rangeRozhdestvensky 2006
Reference buildtwo 600 x 150 mm wings, endplates 30illustrative

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

tandem-wig-configuration-wingekranoplan tandem: span 600, chord 150 mm, anhedral 0°, endplates 30 mm (scale to your craft)STEP · STL
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Plain text: sheet.txt · JSON: /api/geometry?object=tandem-wig-configuration

Tandem-wing ground-effect craft (Jorg type), isometric render of a generated part
Render of tandem-wig-configuration-wing 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
Power-augmented ram (PAR), isometric render of a generated part
Power-augmented ram (PAR)8 sizes★ 1 file
Endplates on ground-effect wings, isometric render of a generated part
Endplates on ground-effect wings3 sizes★ 1 file

Questions

Is a tandem WIG easy to stabilise?

No; Rozhdestvensky calls its stability very sensitive to pitch and clearance.