Houbei Class (Type 022) - Trimaran

The use of advanced trimaran hull showed that the Chinese are able to incorporate advanced European and Australian fast ferry technology a bit faster than the U.S., as American programs to use these ships and this hull technology are only in the design and experiment stage. While the U.S. did use some Australian designed fast ferries in the 2003 Iraq invasion, the U.S. did not have ships coming off the lines, like the Chinese do. On one level, this new FAC was a Chinese program to replace old conventional hull designs, and to exceed the capabilities of Taiwan's new stealthy FAC design. The trimaran hull configuration confers greater high speed capability in heavy weather, while providing a large deck space for multiple uses.

Catamaran vessels have existed for many centuries, mainly for sailing sport. At the end of the 20th century there was an increased trend of employing the catamaran design on high-speed ferries. Although a number of logistic and combat support vessels in the catamaran form were tested in the past, no catamaran had ever been built for direct combat role in the modern naval history. The Type 022 missile FAC was indeed the world's first combat catamaran that had been commissioned. Coincidently, the US Navy was also testing a high-speed, wave-piercing catamaran known as FSF1 "Sea Fighter" for the littoral warfare role.

The wave-piercing catamaran offers great high-speed, long-distance cursing performance. The twin hulls of the catamaran enable the vessel to be more stable when travelling at high speeds than the conventional single-hull craft. Catamarans are especially favourable in coastal shallow waters, where large single-hull warships have limitations due to their deeper draft. The Type 022 missile FAC was likely to be used for costal defence roles in conjunction with larger surface ships and land-based aircraft.

However, the catamaran hull design also has problems. One of them was from the submerged bodies of the hull. Scientists have known that the MUNK moment can cause the motion instability of submerged bodies. So the designer of catamaran will add the stabilized or controlling fins on the submerged bodies. But how to optimize the hydrodynamic of the catamaran was still being research by world.

The Australian company AMD exports various sizes of catamarans for commercial customers from all parts of the world. From 1993 until 2000, China procured seven AMD catamarans from 16 meters long to 30 meters (100 feet) long for river, seaport or local ferry duties. AMD had a joint venture company, Sea Bus International, located in Guangzhou that refined this catamaran design. After a review of competing designs, the PLAN selected a military patrol boat design based on the AMD 350, which was markedly like the Type 022 in specifications.

One notable area in which commercial hull construction was leading military development was the use of aluminum in fast ferries. The extra cost and complexity of designing and building ships with this aluminum are made commercially viable by the speed benefits afforded through lighter weight. The lower structural strength and melting point of aluminum, however, have limited its use in mainstream warship construction. Despite these strength and damage resiliency disadvantages, several navies have turned to aluminum as they look for high speed in specialized littoral warfare and transport vessels. In doing so, they have turned to leading commercial fast-ferry builders (such as Austal of Australia) for not only aluminum welding and fabrication techniques but complete aluminum hull designs.

The trimaran variant of the U.S. Navy's new Littoral Combatant Ship (LCS) was designed and built by Austal USA; in China, the aluminum catamaran hull of the new Type 022 Houbei-class fast attack craft was widely believed to be derived from Western fast-ferry designs. Consequently, whereas traditional types of PLAN frigates and destroyers are likely to draw only general benefits in hull construction quality from commercial shipbuilding development, smaller fast-attack craft and other specialized types may benefit heavily from commercial advances in aluminum hull construction.

Kamewa was a Swedish company which was acquired by the British Vickers group in 1986. Acquiring Vickers in 1999, Rolls-Royce plc now owns the Kamewa portfolio. The Swedish part of the business was called Rolls-Royce AB. Now it was unknown that what the exact type of waterjet was applied in Chinese fast attack craft. The most possibility was the Kamewa FF, a small series of waterjets for applications of 3 to 72 tonnes displacement. Here the individual components of the drive system are located in the stern section of the ship, as was also known from speedboats with waterjets and has long been normal in large shipbuilding for propeller drives. For reasons of effectiveness the waterjets are essentially located so that the jet was freely emitted, i.e. over water. This type of arrangement was however not suitable for achieving the objects in accordance with the invention.