Lattice mast

USS South Carolina, the first American battleship to feature lattice masts.

Lattice masts, or cage masts, are a type of observation mast common on major warships in the early 20th century. They were used most prominently on American dreadnought battleships and armored cruisers of the World War I era. Observation posts were mounted on the masts and used to direct the fire of the warships' guns. The purpose of the lattice structure was to make the posts less vulnerable to shells from enemy ships, and to better absorb the recoil shock associated with firing main guns, isolating the delicate fire control equipment (rangefinders, etc) mounted on the mast tops. The masts are a type of hyperboloid structure, whose weight-saving design was first used by the Russian engineer Vladimir Shukhov.

Use in the United States Navy

The South Carolina class battleships were the first class of American battleships to feature lattice masts, which were to become a standard fixture on all American battleships, and many cruiser classes. All American battleships, up to the Colorado class battleships were equipped with lattice masts, although in the 1920s to 1930s, the older battleships had their lattice masts replaced with more modern tripod masts. The newer Tennessee and Colorado classes retained their original lattice masts at the start of World War II.

Use in the Russian Navy

The two "Andrei Pervozvanny" class battleships had lattice masts until they were replaced with conventional masts in the beginning of the First World War. The four "Gangut" class battleships were designed with lattice masts, but constructed with conical ones.

Use in the Argentine Navy

The two Rivadavia class battleships, the ARA Rivadavia and the ARA Moreno had lattice masts. They were the only dreadnought-type battleships built for export by the USA.

Use in Fortifications

A lattice fire-control mast was installed on Fort Drum, a fort built by the United States to guard the entrance of Manila Bay. The mast directed the fire of the fort's 14-inch main batteries.

References

• Hore, Peter (2006). Battleships of World War I. London: Southwater Books. ISBN 978-1-84476-377-1. 
• Morison, S. L.; Morison, S. E.; Polmar, N. (2003). The American Battleship. Zenith. ISBN 0760309892. http://books.google.com/books?id=SYurkGIlgLMC. 
• Viscount Hythe, (Ed.) (1912). The Naval Annual (Brassey's Naval Annual). Portsmouth: J. Griffin & Co. Archive.org. 
• Melnikov, R. M. (2003). (in Russian) Lineyny korabl "Andrey Pervozvanny" (1906–1925) (Линейный корабль "Андрей Первозванный" (1906–1925)). Saint Petersburg: Korabli i srazheniya. (no ISBN). 
• McGovern, Terrance C. (2003). American Defenses of Corregidor and Manila Bay 1898-1945. Osprey. ISBN 1841764272.