Herewith a 3D printable model of the Amphistar ekranoplan, as it was developed by ATT (Amphibious Transport Technologies) from 1992 onwards. The model has been created in Solidworks, I've included STEP and IGES files, next to seperate STL files for all printable parts. All parts are sized to be printed on print beds of 30x30cm upwards and of course can be resized accordingly. In the standard size the assembled model is 430 x 236 x 134 mm.

A short history: Initially it was called Passat, but was renamed Amphistar in 1996. From 1998 onwards it was also marketed in the USA and the Bahamas under the name Xtreme Xplorer. In april 2000, all vehicles were placed into storage and the company ceased to exist. Within the same period, the new company ATTK (Artic Transport and Trade Co.) completely reworked the design and brought the new 'Aquaglide 5' onto the market, a few years later. The vehicles differ in many details but are clearly based on the same general aerodynamic & mechanical configuration.

The Amphistar was a Type A WIG vehicle (Ekranoplan), actually under the original classification of the CHDB which ran the original ekranoplan programm, it would be classed as a dynamic air cushion vehicle. It follows from a long development lineage (SM-9, SM-10 and Volga 2 Ekranoplans). All these vehicles share a similar configuration, a square wing planform with a wing profile aimed at very high longitudinal stability even in extreme ground effect (Inverted profile with S-shaped camberline) and two forward mounted propellers which can be used to build-up a PAR cushion under the wing for take-off and landing. The Amphistar fuselage is made of GFRP, the sponsons are largely inflatable (which is performed by two on-board compressors). Underneath the forward fuselage, a 3rd inflatable body can be used to push the nose out of the water for initial acceleration or during landing, it is retracted in flight. The stabilizer is up-lifting and has no control surfaces, as such the pilot only has control over throttle, rudder and the angular position of the propellers. A 300bhp Mercedes-Benz engine in the forward fuselage drives the two AV-110 propellers via extension shafts and angular gearboxes.

Several of these vehicles were built and operated/demonstrated all over the world. Since this was in a prototype stage, there are minute differences between the individual produced machines. This 3D model represents the unit which sported a fancy Xtreme Xplorer color sheme and was presented as such at Düsseldorf in 96 and 97. It features an additional air-scoop in front of the wind screen. The centerbody inflatable body is shown in the retracted position, the flight controls are in the cruise-setting. The model can be printed in two large parts which require supports for the forward prop guards and horizontal stabilizer. The propeller extension shafts & propellers are seperate parts so that they can be positioned in any desired attitude. Panel lines are included as fine-detailed recesses, window rubbers are embossed. The CAD model is based on extensive research, accurate drawings from the Aquaglide 5 and a multitude of books & papers released on the development of this machine during its active years.