BUMP silhouette of the American battleship USS Nevada BB-36 in November 1943

BUMP silhouette USS Nevada

Neveda-class battleships for modernizing. Warshipsresearch.blogspot.com

The Coast Artillery School developed for shore-based observation posts the bump-method for spotting and recognizing a ship hull down over the horizon. The method was applying to a ship from the top down and the top third of the superstructure first appearing over the horizon and this reducing to a simplified silhouette, in fact just a rough outline of the characteristic upper portions of the superstructure.

Part of Nevada-class preceded byNew York class succeeded by Pennsylvania-class, building ordered on 4 March 1911, awarded on 22 January 1912, laid down by Fore River Shipbuilding Company on 4 November 1912, launched on 11 July 1914, commissioned on 11 March 1916, modernized August 1927-January 1930 including replacing basket masts by tripod masts, decommissioned on 29 August 1946, stricken on 12 August 1948 and sunk as a target on 31 July 1948.

Sources

John D. Neill, “The Bump Charts” in: Coast Artillery Journal, Jan-February 1944, p. 31-33.

“Bumps. Warships are quickly recognized by new Coast Artillery Bump Silhouettes” in: U.S. Army-Navy Journal of Recognition, November 1943, No. 3., p. 21-25.

ONI. FM 30-50. Recognition pictorial manual of naval vessels, 15 September 1943.