Sea Sparrow

RIM-7 Sea Sparrow
Type	Surface-to-air missile
Place of origin	United States
Service history
In service	1976 – present
Production history
Manufacturer	Raytheon and General Dynamics
Unit cost	$165,400
Specifications
Weight	510 lb (230 kg)
Length	12 ft (3.7 m)
Diameter	8 in (20 cm)
Warhead	Annular blast fragmentation warhead, 90 lb (41 kg)
Detonation mechanism	Proximity fuzed, expanding rod, with a 27 ft (8.2 m) kill radius
Engine	Hercules MK-58 solid-propellant rocket motor
Wingspan	3 ft 4 in (1.02 m)
Operational range	10 nmi (19 km)
Speed	4,256 km/h (2,645 mph)
Guidance system	Semi-active radar homing
Launch platform	Ship

RIM-7 Sea Sparrow is a US ship-borne short-range anti-aircraft and anti-missile weapon system, primarily intended for defense against anti-ship missiles. The system was developed in the early 1960s from the AIM-7 Sparrow air-to-air missile as a lightweight "point-defense" weapon that could be retrofitted to existing ships as quickly as possible, often in place of existing gun-based anti-aircraft weapons. In this incarnation it was a very simple system, guided by a manually aimed radar illuminator.

After its introduction, the system underwent significant development into an automated system similar to other US Navy missiles like the RIM-2 Terrier. Improvements made to the Sparrow for the air-to-air role led to similar improvements in the Sea Sparrow through the 1970s and 80s. After that point the air-to-air role passed to the AIM-120 AMRAAM and the Sea Sparrow underwent a series of upgrades strictly for the naval role. It now resembles the AIM-7 only in general form; it is larger, faster and includes a new seeker and a launch system suitable for vertical launch from modern warships.

Fifty years after its development, the Sea Sparrow remains an important part of a layered air defense system, providing a short/medium-range component especially useful against sea-skimming missiles.

High-speed jet aircraft flying at low altitudes presented a serious threat to naval forces in the late 1950s. Approaching under the local horizon of the ships, the aircraft would suddenly appear at relatively close ranges, giving the ships only seconds to respond before the aircraft dropped their payloads and withdrew. This gave the aircraft an enormous advantage over earlier weapons such as dive bombers or torpedo bombers, whose low speed allowed them to be attacked with some effectiveness by anti-aircraft guns. The advantage was so great that when the Royal Navy was faced by the threat of the new Soviet Sverdlov-class cruiser, they responded in a non-linear fashion by introducing the Blackburn Buccaneer aircraft to attack them.