A thread on the Royal Navy’s options for hard-kill Ballistic Missile Defence and the Type 45 Destroyer:

The requirement for ship-based hard kill defences against ballistic missiles has grown significantly in the past decade, notably with Russia and China both bringing new anti-ship ballistic missiles into service, keeping large capital ships as targets in mind.

The Chinese DF-21D and DF-26 are medium and intermediate range land-based ballistic missiles respectively, the latter of which can reach in excess of 3500km from a coastal battery and threaten ships well into the Pacific.

This range creates a significant A2AD zone around the South China Sea which any carrier strike group must enter (for reference, the F35B has an un-refuelled combat radius of no more than 1100km) if it intends to contest China and its islands militarily.

The same can be said for a possible naval conflict against Russia in the Norwegian Sea. The Kinzhal is an air-launched ballistic missile reaching up to 3000km. It cannot be assumed that surface ships would always have the luxury of staying out of range.

While it is acknowledged that hard-kill ship based defences are just one piece in the puzzle of defence against ballistic missiles, it is still an area in need of development. This thread will explore options to develop ballistic missile defence for the Royal fleet.

The goal of these improvements is not to provide coverage of the UK from ICBMs (a somewhat unrealistic expectation, even for US BMD ships based in Rota) but to provide an air defence bubble against tactical and theatre ballistic missiles launched from coastlines and aircraft.

The Type 45 is the logical platform to inherit a BMD capability, with a relatively large displacement, room for upgrades and are already slated for a purely air-defence role in a carrier group. There are also multiple avenues of development for the current hardware.

BAE’s SAMPSON is the primary target illumination radar of the Type 45 destroyers, guiding Aster missiles in their mid-course to a target. BAE has indicated at plans to give SAMPSON a Ballistic Missile Defence focused upgrade in 2023-2024. ( https://www.baesystems.com/en/productfamily/radar-uk)

S1850M is the long range air-search and tracking radar of the Type 45. Its design is an improvement on the Thales Netherlands SMART-L. S1850M can track aircraft sized targets up to 400km away and has already demonstrated a ballistic missile tracking capability.

Thales Netherlands have developed SMART-L-EWC; a software upgrade for SMART-L boasting improved detection and tracking ranges for conventional and ballistic threats compared to the original SMART-L radar.

SMART-L-EWC (Early Warning Capability), now called SMART-L-MM (Multi-Mission), has been installed to all 4 De Zeven Provincien class frigates of the Royal Netherlands Navy with the option of operating in a BMD air search mode.

The Aster missile family also has also options for improvements to defend against ballistic missiles. Block 0 is the version currently in use with the Royal Navy and most naval ships equipped with the Aster system. It currently has a relatively limited BMD capability.

Aster Block 1 is a software upgrade to the seeker of the missile, allowing for enhanced targeting and interception of Short Range Ballistic Missiles. It is currently in service with France and Italy as part of the SAMP/T ground based Aster system.

Aster Block 1 NT (New Technology) uses an upgraded seeker operating in the Ka band. This increases the target acquisition range and resolution for the Aster missile when operating in its final phase. This will allow for interception of ballistic missiles of a 1500km range.

Block 1 NT will be delivered to the French Air Force in 2023 for use in the SAMP/T ground based air defence system. Block 1 NT will also be procured for the Italian Navy for use in 5 PPA frigate’s A70 Sylver VLS cells. B1 NT could also fit in the A50 cells of the Type 45s.

Block 2 BMD is an MBDA program to produce a missile purely dedicated to BMD; it improves on the Aster B1 NT by targeting MRBMs of the 3000km range class, confidently putting it within a chance of intercepting Chinese DF-21 and DF-26 anti-ship ballistic missiles.

However, there has been little input from MBDA on the state of the program, indicating it is some time from entering service. Selecting B2 as the Royal Navy’s desired BMD weapon would mean a significant waiting time and leaves carrier groups vulnerable to ballistic threats.

The US fill the ship-based BMD requirement with the Standard Missile 3. The SM3 works similarly to the planned Aster B2 using an exo-atmospheric kinetic warhead, a much more effective means of intercepting ballistic missiles.

The SM3’s Lightweight Exo-Atmospheric Projectile intercepts ballistic targets higher up in the atmosphere where the likelihood of the target manoeuvring to avoid interception is far lower due to the thinner atmosphere and subsequently reduced effectiveness of control surfaces.

Targeting ballistic missiles in this stage has a greater chance of successful interception and a defensive missile which operates in this way should be a procurement focus for the UK.

Procuring SM3s may also be more favourable for the Royal Navy as it would allow for the acquirement a BMD capability far sooner than the Aster B2 option. SM3s are also in widespread use, reducing costs and benefitting from continued development and testing from the US.

Any intent of firing of SM3s from a Type 45 would necessitate the installation of the often referenced 16 Mk41 VLS cells, of which space is provisioned forwards of the Sylver VLS cells. Despite extra costs, this would see a massive increase in capability for the Type 45s.

It has not been confirmed as to whether Aster B2 BMD would fit in existing A50 cells or also necessitate the installation of longer A70 cells. It should be noted that using BMD missiles in some of the fitted 48 cells would detract from its conventional air defence capability.

With the doctrinal shift towards carrier deployments focused around the Indo-Pacific, it would be a sensible notion to develop a sovereign BMD capability and reduce reliance on an SM3 carrying Arleigh Burke being permanently attached to the group.

Correction: SMART-L-MM is an AESA radar compared to the original PESA SMART-L, meaning the EWC upgrade is more than just a software upgrade.

Correction: Aster block 1 uses a new dual-warhead compared to block 0, meaning the upgrade is not exclusively software based. However, it is possible to retrofit existing block 0 stocks to block 1 standard.

SMART-L-ELR (Extended Long Range) is a BMD focused data processing based upgrade that was trialled in 2006 and fitted to the De Zeven Provincien class frigates. SMART-L-EWC early Warning Capability) is a culmination of the ELR upgrade and a front-end upgrade to an AESA panel.

UPDATE: Aster block 2 has likely been subsumed into the European TWISTER program, which plans to produce sea and land based ballistic/hypersonic interceptors.