The Russian Navy is buying three air cushion amphibious craft for their naval forces in the Caspian Sea. These Serna class craft are 25.8 meters (57 feet) long and displace 100 tons. Each one can haul a tank, or two smaller armored vehicles, or 92 troops, or 50 tons of cargo. Top speed is 54 kilometers an hour and range is 180 kilometers. The crew of four usually stays at sea less than 24 hours per trip. There are already nine Serna craft in service and the new order will make it twelve. The Sernas entered service in 1994, and the last one was built two years ago. This latest order is apparently to keep the production capability alive. Getting more Sernas into action on the Caspian might attract more customers, but the big problem is that these craft are expensive to buy and operate and are really only useful in coastal waters.
Russia has been more interested in building and exporting their larger Zubr class air cushing vehicles, a 555 ton craft that can carry 130 tons (three tanks or a combination of lighter armored or non-armored vehicles). Top speed is 110 kilometers an hour and range is 480 kilometers. The crew of 31 usually stays out less than eight hours per mission. The Zubrs also carry two stabilized MLRs (multiple tube rocket launchers), four short range anti-aircraft missiles systems (Igla-1Ms), and two AK-630 six-barrel 30mm close-in weapon systems (CIWS), for defense against anti-ship missiles.
China ordered some Zubrs seven years ago, largely because most Chinese LCACs were designed and built in China but could only carry about twenty soldiers or two tons of cargo. These were used to quickly get troops from amphibious ships to shore. Since 2005, these have been supplemented by larger JingSah II LCACs. Four of them are carried on each of the larger amphibious ships.
The Zubrs, with a top speed of 100 kilometers an hour, can go right from the Chinese coast to Taiwan and land troops and armored vehicles on shore areas that would otherwise not be passable by troops coming in on standard amphibious boats. The original deal was for two Zubrs to be bought from Ukraine and the other two to be built in China under license. These craft are expensive (the price and weapons configuration is negotiable but the cost is somewhere over $10 million each) and China might only want to buy a few to get some experience and figure out how to build their own. This appears to be what happened, as the deal has since been recast, with all the manufacturing being done in China.