page_title: Brandenburg-class battleship
section_title: Armor
hierarchical_section_title: Brandenburg-class battleship / Design / Armor
caption_attribution_description: S.M. Linienschiff Weissenburg.
context_page_description: The Brandenburg class consisted of four pre-dreadnought battleships built for the German Kaiserliche Marine, the first modern battleships of the fleet. The four ships of the class—Brandenburg, Wörth, Weissenburg, and Kurfürst Friedrich Wilhelm—were the first ocean-going capital ships built for the German fleet in nearly two decades, owing to reluctance in the Reichstag to fund large projects. They followed a series of small coastal defense ships, and though in retrospect they anticipated the buildup that created the High Seas Fleet, they were ordered as part of a construction program that reflected the strategic and tactical confusion that affected many navies in the 1880s. The design process that resulted in the Brandenburg class was very lengthy, with proposals that ranged from outdated casemate ships to versions with two twin-gun turrets placed side by side. The designers ultimately settled on ships that were armed with an unusual main battery of six 28 cm guns at a time when all foreign battleships were built with four or fewer heavy guns.
context_section_description: The first two ships, Brandenburg and Wörth, received compound armor, then the standard type of steel armor, manufactured by Dillinger Hütte, but at the time, Krupp was experimenting with a new nickel-steel armor that was ordered for Weissenburg and Kurfürst Friedrich Wilhelm. The compound armor was constructed by welding hardened steel together with more flexible wrought iron plates to take advantage of the hardness of steel and the greater flexibility of wrought iron to break up and then contain incoming shells. Krupp's nickel steel armor was based on the Harvey process, which enriched the upper layers of the steel with carbon. The process hardened the outer layer while retaining greater flexibility at the back of the plate; the fact that the new armor plate consisted of a single forging instead of multiple plates welded together gave it greater strength. This allowed the use of thinner (and thus lighter) armor belts that provided the same level of protection, which in turn permitted more comprehensive protection for the same weight of armor. Some portions of Brandenburg did receive the new Krupp armor, including the barbettes that held the fore and center main battery turrets. All four ships retained teak backing to their armor belts. The teak was used to help absorb the shock of a torpedo or naval mine detonation.
  The side protection system followed the so-called "French principle", using a narrow, full-length armored belt to protect the hull, rather than a shorter citadel system that only protected a ship's ammunition magazines and propulsion machinery spaces. The belt extended from 0.8 m (2 ft 7 in) above the waterline to 1.6 m (5 ft 3 in) below, though toward the bow it was extended further down to reinforce the ram. Above the waterline, the armored belt was 300 mm (11.8 in) forward and as the belt moved further aft, it stepped up to 330 mm (13 in), then to 380 mm (15 in), and finally to 400 mm (15.7 in) in the central portion of the ship where it protected the magazines and machinery spaces. Further aft, it tapered to 350 mm (13.8 in) and then to 300 mm toward the stern. Below the waterline, the armored belt was significantly thinner; like the upper belt, it tapered toward the ends. It started at 150 mm (5.9 in) at the bow, increasing to 180 mm (7.1 in), then to 190 mm (7.5 in), and then to 200 mm (7.9 in) thick amidships, and tapered down to 180 mm (7.1 in) on the aft end of the belt. The teak backing for the belt amounted to 200 mm, and the whole assembly was bolted together.
  The Brandenburgs had an armored deck 60 mm (2.4 in) thick that was connected to the upper edge of the belt; it was effective only at deflecting short-range shells and could not have resisted plunging fire or a shell that detonated on impact. The forward conning tower had 300 mm sides and a 30 mm (1.2 in) roof. The barbettes for the main battery turrets were 300 mm thick and backed with 210 mm (8.3 in) of teak. The gun houses for the main battery had 50 mm (2 in) roofs and sides that consisted of three 40 mm (1.6 in) layers, for a total of 120 mm (4.7 in). The 10.5 cm and 8.8 cm guns received gun shields that consisted of two plates of steel bolted together; each shield consisted of a 20 mm (0.79 in) plate and a 22 mm (0.87 in) plate.
caption: Lithograph of Weissenburg
exif: {"Image Software": "Picasa", "Image DateTime": "2012:04:22 12:41:03", "Image Artist": "Picasa", "Image ExifOffset": "96", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "364", "Thumbnail JPEGInterchangeFormatLength": "4876", "EXIF ExifVersion": "0220", "EXIF DateTimeOriginal": "4501:01:01 00:00:00", "EXIF ExifImageWidth": "12853", "EXIF ExifImageLength": "8113", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "Interoperability RelatedImageWidth": "10521", "Interoperability RelatedImageLength": "14868", "EXIF InteroperabilityOffset": "228", "EXIF ImageUniqueID": "bd5aee658800960f89509cb82dd5534e"}