The project of amphibious boats of the project 21820 was developed in the "Central Design Bureau for the SEC named after R. E. Alekseev". The predecessor of this project, which still has no world analogues — the high-speed amphibious boat project 11770 "Serna", was also developed in the Central Design Bureau for Hydrofoils named after him. Project 21820 Dugong air cavity landing craft went into production in 2006. The boat has a jet propulsion and is able to move in shallow water, while developing a speed of 65 km / h. The hull of the boat is made of an alloy of aluminum and magnesium and is armed with two 14.5-mm heavy machine guns and 8 Igla or Verba MANPADS. The ship can be used in stormy conditions with a wave height of not more than 3.5 meters. The boat is able to take on board, depending on the task, 2 tanks or 4 infantry fighting vehicles or 90 troops. The range of the boat is 500 miles, the crew of the boat is 6 people. Now Russia has 5 boats of project 21820, the construction of ships of this project continues.