Wing-in-Ground (WIG) craft development took a firm step forward with the recent announcement that two Korean companies –  Daewoo Shipbuilding & Marine Engineering (DSME) and Wing Ship Technology Corp –   are to co-operate to make production of WIG craft a viable operating and commercial proposition. The offshore support vessel market is in their sights, and they also have plans to develop a 200-seat WIG craft for military use.

Wing Ship Technology successfully produced their 50-seat prototype WSH-500 (classed by Lloyd’s Register) late last year with $6.3 million funding assistance from DSME.

Wing-in-Ground Effect Craft WSH-500: Photo courtesy of Wing Ship Technology Corp.

WIG Concept & Maritime Safety

A WIG craft is a vessel capable of operating completely above the surface of the water on a dynamic air-cushion. The 'ground effect' refers to what a pilot (commonly passengers too ) feels when landing a large aircraft – just before touchdown it’s as if the plane wants to go on and on – due to the cushion of air trapped between the wings and the runway. Hence ‘aerodynamic ground effect’.

Presently there are no safety standards in place for WIG craft, although the International Maritime Organisation (IMO) did publish interim guidelines ten years ago. The United States Coast Guard, in conjunction with the Federal Aviation Administration and the IMO (a pairing that underlines the WIG concept’s intersection with both air and sea) say this is a work in progress.

Propulsion & General Particulars WSH-500

Gas Turbine Engine by MTT & Shaft Prop: Photo courtesy of MTT

US-based MTT Corp was contracted to design the special 1,400 hp gas-turbine propulsion systems for the WSH-500 to drive customised 10 ft propellors developing 4,800 lbs thrust.

German naval architect Hanno Fischer, a pioneer in WIG craft development, brought his expertise to bear on the Korean initiative by Wing Ship Technology (founded in 2007) to develop the WSH-500, and the builders say they intend four vessels for delivery in the current year at a price of about US$ 6.7 million each for the basic configuration.

Principal particulars are as follows:

• Passenger capacity: 47 passengers and 3 crew
• LOA: 28.5 m (93.5 ft)
• Breadth overall: 27 m (88.6)
• Height: 6.7 m (22 ft)
• Displacement: 17.1 tons
• Construction material: aluminium alloy
• Propulsion: MTT gas-turbine: 2 x 1,400 Turbo-shaft/Prop
• Cruising speed 100 kts (on trial achieved 73 kts in GE mode)
• Fuel: 1 tonne capacity, consumption about 250 kg/hr
• Range: 300 (162 nm)
• Cruising height: 1 to 5 m (3.3 to 16.4 ft) with safe landing at all times

WIG Craft Advantages

High speed transportation without the need of an airport is the great advantage. Speeds of a light aircraft or helicopter are capable of being matched, but require less redundant systems as the craft can land quickly and smoothly in an emergency.

The designers reported good stability and minimal pitch and roll during sea trials of the WSH-500 in air-borne operating mode, assuring passenger comfort.

DSME vice president Y.Y. Koh said WIG craft are well suited to meet the needs of the offshore market, considering that they were safer and more economical than widely-used helicopters.