Sea Sparrow surface to air missile

Sea Sparrow was developed from the AIM-7 Sparrow air-to-air missile as a lightweight "point defence" weapon that could be retrofitted to existing ships, often in place of existing gun-based anti-aircraft weapons.


 The primary development issues were changes to the seekers to allow them to operate with shipboard radars, and the new Mark 25 trainable launcher system, based on the ASROC launcher, to align the seeker head with the target before launch.


Combined with a Mark 115 manned fire control director it was known as the Basic Point Defence Surface Missile System (BPDSMS) or just BPDMS.

As a surface-to-air system, the Sparrow has a number of disadvantages. For one, the missile steers with its mid-mounted wings, which initially made them unfoldable. For this reason the missile takes up much more room than it would have to if the wings could be folded.


Additionally the engine is optimized for flight time, as opposed to fast acceleration, which makes sense when launched from an aircraft moving at high speed at a target at long range. In the surface-to-air role, however, one would rather have very high acceleration in order to allow it to intercept sea-skimming targets as soon as possible.


Furthermore, the Sea Sparrow possesses a shorter range than its air-to-air counterpart. Some estimates indicate that it may be effective only to 10 nm, about one quarter of the range of the AIM-7 Sparrow.

In order to address these issues, a consortium of many Sea Sparrow users joined together to create the Evolved Sea Sparrow Missile (ESSM).


The RIM-162 Evolved Sea Sparrow Missile (ESSM) is a development of the RIM-7 Sea Sparrow missile used to protect ships from attacking missiles and aircraft. ESSM is designed to counter supersonic manoeuvring anti-ship missiles.


Compared to the Sea Sparrow, ESSM has a larger, more powerful rocket motor for increased range and agility, as well as upgraded aerodynamics using strakes and skid-to-turn. In addition, ESSM takes advantage of the latest missile guidance technology, with different versions for Aegis/SPY-1, Sewaco/APAR, and traditional target illumination all-the-way. ESSM also has the ability to be "quad-packed" in the Mk 41 VLS system, allowing four times the number of Sea Sparrow to be carried.

ESSM will be used by many allied countries. The first country to achieve operational status for ESSM after the United States was Australia. Other countries which also integrated the ESSM are The Netherlands, Germany and Norway. Other countries in the process of integrating ESSM are Canada, Denmark, Greece, Japan, Spain and Turkey.


Type Medium range surface-to-air missile
Manufacturer Raytheon
Weight 231kg
Warhead 40kg annular blast fragmentation, continuous expanding rod with a proximity fuse
Length 3.6m
Diameter 20.3cm
Wingspan 1m
Performance Speed Mach 4, range 55km, guidance semi-active radar