My thoughts on this: https://twitter.com/rwjthomas/status/1381970648348516363

Sensors - The difference between SAMPSON and SPY/1 is more than just age. SAMPSON as a system has a deliberate trade-off between power (i.e. range) and weight. A lightweight system can be placed on a higher mast and has a further radar horizon.

Using just two small AESA panels back to back (plus being exclusively air cooled and using lightweight materials), SAMPSON is a far lighter system compared to the 4 large, heavy radar panels of SPY/1. SAMPSON is mounted on a tall mast compared to the superstructure mount of SPY/1

This gives more time to react against sea-skimming missiles (a lesson learned in the Falklands war - see radar positioning of Type 42 vs Type 23).

However, using such a lightweight system has its drawbacks. For example, SAMPSON’s range is likely inferior to that of SPY/1 based on the peak power draw of each system and the size of the arrays.

Fortunately SAMPSON is used in conjunction with S1850M (a larger, more powerful radar) to provide early warning detection against high-flying targets.

This means that SAMPSON can be left to the job of closer range low-level detection and tracking of incoming threats, whilst also guiding Aster missile to intercept (during their mid-course; final phase target tracking is handled by the Aster’s onboard seeker).

SAMPSON’s use of two back to back arrays means there are dead zones at the extreme angles of each array. This is mitigated by rotating the radar and moving the radar beams electronically to cover the gap, however it is still a disadvantage compared to SPY/1’s constant coverage.

SAMPSON is an Active Electronically Scanned Array (AESA) compared to SPY/1’s Passive Electronically Scanned Array. Functionally, this means that SAMPSON can simultaneously emit multiple frequencies of a wider range. This can improve target detection and

increases resistance to electronic jamming by using a wide range of frequencies. It is also less likely to be intercepted because a wide frequency band is harder to distinguish from background noise. Typically, AESA radars are also lighter than their PESA counterparts.

With the newer SPY/6 and SPY/3 AESA radars coming into service, some of SAMPSON’s current advantages will be surpassed. However, SAMPSON will still retain the advantage of weight and distance to the horizon which the US cannot equal bar a new ship class/redesign.

Effectors - firstly, the obvious point is the disparity in VLS cells (122 vs 48). Even when you factor in that t a Tico may be carrying Tomahawk cruise missiles and VL-ASROC anti-submarine rockets in some of those cells, the difference in the number of munitions that can be

thrown at a target is apparent. Ticonderogas also have the option of quad-packing some cells with smaller missiles (ESSM). However, this disparity is reduced by a number of factors:

The US’ primary AAW missile, the SM2, uses semi-active radar homing. This means that the radar seeker in the missile’s nose cone cannot emit a radar signal, only receive one. Therefore the target must first be ‘illuminated’ by using X-band emitters from the ship itself.

The Ticonderoga has 4 of these illumination radars, meaning the number of missiles in the air at one time is likely not much higher than this. Comparatively, the Aster missiles used on a Type 45 are fully active-homing, meaning that, when close enough,

the Aster missile can independently detect and track the target without input from the launch platform. Not only is this generally a more reliable system, it allows for a greater number of targets to be intercepted at a given time.

As the US increases its stockpile of active-homing SM6 missiles this advantage will be reduced. However, it is likely that SM6 will not fully replace SM2 for a long time.

Another advantage of Aster is the use of lateral thrusters which propel the missile sideways and produce extreme g forces and manoeuvrability. This means that, against a conventional AAW target like a supersonic cruise missile, Aster could have a greater probability of kill.

However, this general advantage of the Sea Viper system (SAMPSON and Aster) only applies to conventional anti-ship cruise missiles. For ballistic missiles, the Type 45 has next to no capability to track and intercept them.

I wrote more about this issue specifically here https://ukdefencejournal.org.uk/ballistic-missile-defence-and-the-type-45-destroyer/

Another advantage of the Ticonderoga/Arleigh Burke platform is its potential involvement in the US’ ‘Cooperative Engagement Capability (CEC)’ program. This envisages a network of assets where the ‘sensor’ is not necessarily the on same platform as the ‘shooter’.

This allows for aerial assets like the E2 Hawkeye to network with a Ticonderoga and guide SM6 missiles to the target beyond the Tico’s radar horizon. This capability is not to be understated as missiles become faster and harder to intercept.

This capability was also an option for the Type 45s (albeit to a lesser extent)mbut was cancelled on cost grounds (despite being a justification used by some for a reduction in hull numbers).

Overall the Type 45 vs Ticonderoga debate is very nuanced and depends on a variety of factors. Where the Type 45 is very good at the specific task it was designed to complete, it lacks in other areas which makes the Tico a better overall asset (without even mentioning ASW,ASuW)

The Type 45s are excellent platforms but should not be put on a pedestal of superiority like they often are and are just as vulnerable to obsoletion without upgrades.