Fritz X

Fritz X
Side view of a Fritz X in the RAF Museum London (2010)
Type	Anti-ship missile / Guided bomb
Place of origin	Nazi Germany
Service history
In service	1943–44
Used by	Nazi Germany (Luftwaffe)
Wars	World War II
Production history
Designer	Max Kramer
Manufacturer	Ruhrstahl
Specifications
Weight	1,362 kg (3,000 lb)
Length	3.32 m (11 ft)
Width	1.40 m (5 ft)
Diameter	85.3 cm (2 ft 8 in)
Warhead	amatol explosive, armour-piercing
Warhead weight	320 kg (705 lb)
Operational range	5 km (3.1 mi)
Speed	343 m/s (1,235 km/h or 770 mph)
Guidance system	Kehl-Straßburg FuG 203/230; MCLOS

Fritz X was the most common name for a German guided anti-ship glide bomb used during World War II. Fritz X was the world's first precision guided weapon deployed in combat, and the first to sink a ship in combat. Fritz X was a nickname used both by Allied and Luftwaffe personnel. Alternative names include Ruhrstahl SD 1400 X, Kramer X-1, PC 1400X or FX 1400 (the latter, along with the unguided PC 1400 ordnance's Fritz nickname, is the origin for the name "Fritz X"). Along with the USAAF's similar Azon weapon of the same period in World War II, it is one of the precursors of today's anti-ship missiles and precision-guided weapons.

The Fritz X was a further development of the PC 1400 (Panzersprengbombe, Cylindrisch 1400 kg) armour-piercing high-explosive bomb, itself bearing the nickname Fritz. It was a penetration weapon intended to be used against heavily protected targets such as heavy cruisers and battleships. It was given a more aerodynamic nose, four stub wings, and a box shaped tail unit, consisting of a roughly 12-sided annular set of fixed surfaces, and a cruciform tail with thick surfaces within the annulus, which themselves contained the Fritz X's aerodynamic controls. The Luftwaffe recognized the difficulty of hitting moving ships during the Spanish Civil War.Dipl. engineer Max Kramer, who worked at the DVL, had been experimenting since 1938 with remote-controlled free-falling 250 kg bombs, and in 1939 fitted radio-controlled spoilers. In 1940, Ruhrstahl was invited to join the development, since they already had experience in the development and production of unguided bombs.

Fritz X was guided by a Kehl-Strasbourg radio control link, which sent signals to the movable spoilers in the thick vertical and horizontal tail fin surfaces, within the annular tailfin structure. This control system was also used for the unarmored, rocket-boosted Henschel Hs 293 anti-ship ordnance, itself first deployed on August 25, 1943. The Straßburg receiver's antenna installations on the Fritz X were aerodynamically integrated into the trailing edge of the annular surfaces of the tailfin, within a quartet of "bulged" sections in the trailing edge. This design feature of the Fritz X's FuG 230 Straßburg receiver installation is not entirely unlike the Azon, which had its own receiving antennas placed in the quartet of diagonal struts bracing the fixed sections of its tailfins.