Aegis Combat System
The Aegis Combat System is controlled by an advanced, automatic detect-and-track, multi-function three-dimensional passive electronically scanned array radar, the AN/SPY-1.
In December 2019, Lockheed Martin released a promotional video heralding the 50th anniversary of the Aegis combat system.
These were sufficient weapons but by the late 1960s, the U.S. Navy recognized that reaction time, firepower, and operational availability in all environments did not match the anti-ship missile threat.
An Advanced Surface Missile System (ASMS) was promulgated and an engineering development program was initiated in 1964 to meet the requirements.
[12] During this time frame, the Navy envisioned installing the Aegis Combat System on both a nuclear-powered "strike cruiser" (or CSGN) and a conventionally-powered destroyer (originally designated DDG 47).
As compared to the CSGN, this design was not as survivable and had reduced command and control facilities for an embarked flag officer.
Ultimately this design was also cancelled during the Carter Administration due to its increased cost compared to the non-nuclear DDG 47.
During 1980, the Arleigh Burke-class destroyer was designed using an improved sea-keeping hull form, reduced infrared and radar cross-sections, and upgrades to the Aegis Combat System.
Flight II of the Arleigh Burke class, introduced in 1992, incorporated improvements to the SPY-1 radar, and to the Standard missile, active electronic countermeasures, and communications.
Recent Aegis Combat System ships come with active electronically scanned array radars which use solid-state gallium nitride emitters.
[18] To enable Ballistic Missile Defense capabilities, signal processing for the SPY-1 radar was upgraded using commercial off-the-shelf components and open architecture standards.
[19] The Multi-Mission Signal Processor (MMSP) provides Anti-Air Warfare (AAW) and Ballistic Missile Defense (BMD) capability for the first 28 ships (DDGs 51–78) of the U.S. Navy's Arleigh Burke-class destroyers.
MMSP improves performance in littoral, ducted clutter, electronic attack (EA), and chaff environments and provides greater commonality in computer programs and equipment.
[20][21] As of January 2025, the U.S., Japan, and South Korea[22] are the only countries to purchase or deploy the Aegis BMD on their military ships.
[23] U.S. Army Integrated Air and Missile Defense Battle Command System (IBCS) program aims to integrate Aegis BMD and its AN/SPY-1 and AN/SPY-6 radars with MIM-104 Patriot (AN/MPQ-65A and GhostEye), NASAMS (GhostEye MR), AN/TPY-2 (THAAD and GMD), and F-35 Lightning II (AN/APG-81) radars to form a plug and fight network of land, sea, and air-based sensors to help detect and track ballistic missile threats and select Patriot and THAAD surface-to-air launchers that are best positioned for a successful intercept.
[29] The Japanese Maritime Self Defense Force (JMSDF) currently operates four Kongō, two Atago, and two Maya-class guided-missile destroyers as part of its "Aegis Afloat" program (See table below).
[30][31][32][33] On 6 October 2022, five warships from the United States, Japan, and South Korea held a multilateral ballistic missile defense exercise in the Sea of Japan (pictured) as part of the military response to ongoing North Korean intermediate-range ballistic missile tests over the Japanese home islands.
Two additional ICBMs were subsequently launched on 20 February 2023, with both landing in the Sea of Japan off the east coast of the Korean Peninsula.
A Navy panel headed by retired Vice Adm. Phillip Balisle issued the "Balisle report," which asserted that over-emphasis on saving money, including cuts in crews and streamlined training and maintenance, led to a drastic decline in readiness, and left Aegis Combat Systems in low state of readiness.
[44] The Aegis system was involved in a disaster in which USS Vincennes mistakenly shot down Iran Air Flight 655 in 1988 resulting in 290 civilian deaths.
A formal military investigation by the United States Navy concluded that the Aegis system was completely operational and well maintained.
The investigation found that if the commanding officer had relied on the complete tactical data displayed by the Aegis system, the engagement might never have occurred.
Additionally, psychological effects of the crew subconsciously manipulating the data to accord with a predefined scenario greatly contributed to the false identification.
[48] USCENTCOM stated that both the pilot and weapon systems officer ejected and were recovered safely shortly after, with only one receiving minor injuries after an initial assessment.
