Vertical launching system

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For the Brazilian Space Agency launcher, see VLS-1.
The VLS cells on board USS San Jacinto.
A Tomahawk missile canister being loaded into a VLS aboard the Arleigh Burke class destroyer USS Curtis Wilbur

A vertical launching system (VLS) is an advanced system for holding and firing missiles on mobile naval platforms, such as surface ships and submarines. Each vertical launch system consists of a number of cells, which can hold one or more missiles ready for firing. Typically, each cell can hold a number of different types of missiles, allowing the ship flexibility to load the best set for any given mission. Further, when new missiles are developed, they are typically fitted to the existing vertical launch systems of that nation, allowing existing ships to use new types of missiles without expensive rework. When the command is given, the missile flies straight up long enough to clear the cell and the ship, and then turns on course.

A VLS allows surface combatants to have a greater number of weapons ready for firing at any given time compared to older launching systems such as the Mk-13 single-arm and Mk-26 twin-arm launchers, which were fed from behind by a magazine below the main deck. In addition to greater firepower, VLS is much more damage tolerant and reliable than the previous systems, and has a lower radar cross-section (RCS). The U.S. Navy now relies exclusively on VLS for its guided missile destroyers and cruisers.

The most widespread vertical launch system in the world is the Mk 41, developed by the US Navy. More than 11,000 MK 41 VLS missile cells have been delivered, or are on order, for use on 186 ships and 19 ship classes, in 11 navies around the world. This system currently serves with the US Navy as well as the Australian, Canadian, Danish, Dutch, German, Japanese, New Zealand, Norwegian, South Korean, Spanish, and Turkish navies, while others like the Greek Navy preferred the similar Mk 48 system.[1]

The advanced Mk 57 vertical launch system is projected to be used on the new Zumwalt class destroyer. The older Mk-13 and Mk-26 systems remain in service on ships that were sold to other countries such as Taiwan and Poland.

When installed on an SSN (nuclear-powered attack submarine), a VLS allows a greater number and variety of weapons to be deployed in comparison to using only torpedo tubes.

Hot launch and cold launch[edit]

Diagram depicting a hot launch from a Mark 41 VLS

A vertical launch system can be either hot launch, where the missile ignites in the cell, or cold launch, where the missile is expelled by gas produced by a gas generator which is not part of the missile itself, and then the missile ignites. "Cold" means relatively cold compared with rocket engine exhaust. A hot launch system does not require an ejection mechanism, but does require some way of disposing of the missile's exhaust and heat as it leaves the cell. If the missile ignites in a cell without an ejection mechanism, the cell must withstand the tremendous heat generated without igniting the missiles in the adjacent cells.

US Navy Mk 41 Tomahawk launch, hot launch.

An advantage of a hot-launch system is that the missile propels itself out of the launching cell using its own engine, which eliminates the need for a separate system to eject the missile from the launching tube. This potentially makes a hot-launch system relatively light, small, and economical to develop and produce, particularly when designed around smaller missiles. A potential disadvantage is that a malfunctioning missile could destroy the launch tube.

The advantage of the cold-launch system is in its safety: should a missile engine malfunction during launch, the cold-launch system can eject the missile thereby reducing or eliminating the threat. For this reason, Russian VLSs are often designed with a slant so that a malfunctioning missile will land in the water instead of on the ship's deck. As missile size grows, the benefits of ejection launching increase. Above a certain size, a missile booster cannot be safely ignited within the confines of a ship's hull.

American surface-ship VLSs have the missile cells arranged in a grid with one lid per cell and are "hot launch" systems; the engine ignites within the cell during the launch, and thus it requires exhaust piping for the missile flames and gasses. France, Italy and Britain use a similar hot-launching Sylver system in PAAMS. Russia produces both grid systems and a revolver design with more than one missile per lid. Russia also uses a cold launch system for some of its vertical launch missile systems, e.g., the Tor missile system. The People's Republic of China uses a circular "cold launch" system that ejects the missile from the launch tube before igniting the engine on the Type 052C destroyer, and also a rectangular ”hot launch" system with one lid per cell arranged in a grid on the Type 054A frigate.

Systems in use by nations[edit]

 Australia
 Belgium
 Canada
 Chile
 People's Republic of China
 Denmark
 France
 Germany
 Greece
 India
 Indonesia
SYLVER cells of Italian destroyer Caio Duilio
 Israel
 Italy
 Japan
 New Zealand
 Republic of Korea
 Netherlands
 Norway
 Portugal
Soviet missile cruiser Frunze firing a missile from the Tor VLS
Top view of the Ticonderoga-class USS Lake Champlain (CG-57) with VLS visible fore and aft as the gray boxes near the bow and stern of the ship.
 South Africa
 Russia
 Singapore
 Spain
 Thailand
 Turkey
 United Kingdom
Surface
Submarine
 United States
Surface
Submarine

See also[edit]

References[edit]

External links[edit]