Ballistic Missile Defence for Pohjanmaa?

As was noted earlier Finland has requested the export of quad-packed ESSM surface-to-air missiles for fitting in the Mk 41 vertical launch system (VLS). In itself the request was rather unsurprising, but I did find it odd that the Navy was asking about the canister designed for the Mk 41 and not the dedicated Mk 56 ESSM VLS.

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Mk 41 Strike length launchers in action, as the destroyer USS Donald Cook (DDG 75) fires a TLAM cruise missile against Iraqi targets in 2003. Source: US Navy via Wikimedia Commons

This week a key part of the answer was revealed, as the DCSA report for the Mk 41’s themselves was released. The Finnish request is for four 8-cell Mk 41, of the full-long ‘Strike length’ version. This is the same as carried by US Navy (and Japanese) destroyers and cruisers, as well as by a number of NATO frigates. The options for the strike length launcher include a large variety of US-built surface-to-air missiles, as well as the TLAM (Tomahawk) long-range cruise missile and the VL-ASROC anti-submarine weapon (a rocket which carries a parachute-retarded anti-submarine torpedo out to a considerable range). The downside is the size. To fit the large missiles, the cells are 7.6 m long. The logical choice if one want to fit Mk 41 solely for use with ESSM’s into a corvette is the 5.2 m Self-defense module. In between the two is the 6.7 m Tactical length cells, which add the SM-2 long-range SAM and the ASROC, but is unable to fit the TLAM or the SM-6/SM-3/SM-2 Blk IV (SM-2 with a booster). The SM-2 Blk IV and SM-3 are able to target ballistic missiles, while the SM-6 is a longer-range missile against airborne targets.

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Concept render showing the key combat systems of the vessel. Note the placement of the surface-to-air missiles. Source: Finnish MoD

Now, as late as last week I said in a discussion that it is not possible to fit the Strike length cells on the Pohjanmaa-class, as they are too long for a corvette. In all renders so far the VLS cells have been fitted in front of the superstructure, on deck level. Considering the low draft of the Pohjanmaa-class corvettes, just over 3 meters, it is doubtful whether the cells can be fitted within the confines of the bow. However, if the single cell is mounted along the centreline as opposed to across it, and if it gets a stepped platform a’la Type 26, it just might be doable (or a reshuffle with the Mk 41’s moving into the superstructure and the SSM’s moving to the foredeck/mission bay/further forward/aft/somewhere else).

So why would the Navy be interested in a cell that is two sizes larger than the missile they are planning on pairing it with? The answer is likely that they want to keep all options open. While I very much doubt that the ASROC would fit Finnish doctrine, the TLAM could open up new possibilities. However, if the Defence Forces want more cruise missiles, buying more of whatever will replace the JASSM on the winner of the HX-program is likely the better option (or alternatively buying a long-range weapon for the M270 MLRS). However, the possibility to provide some measure of protection against ballistic missiles might be of interest. While it certainly would be a major undertaking, the vessels will be in service for a long time and “fitted for but not with” is a time-honored tradition when it comes to naval shipbuilding. It should be noted that all kinds of ballistic missile defences are politically highly sensitive. Analysts have noted the similarities to the acquisition of the multirole F/A-18 Hornet back in the day, where even if the fighters were capable of flying ground attack missions, political considerations meant that the capability was only taken into use at a later stage, with the MLU2 mid-life upgrade.

The strike length cells also open up the possibility to fit some interesting anti-ship missiles in the future, as both the LRASM and the JSM are currently being tested in configurations suitable for launch from the Mk 41. Being able to swap out a number of SAM’s for more anti-ship missiles might be an interesting option at some point down the road (or at least interesting enough that the Navy doesn’t want to close the door just yet).

I will admit that the latest development have taken me by surprise. However, it does seem like the Navy is serious about fitting the vessels with systems that will allow them to field firepower to rival some significantly larger vessels. The question is whether the budget will live up to the ambitions?

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No Finnish Harpoon/ESSM-order (at least for now)

As the headline says, yesterday’s big news from the naval sector is not that Finland has ordered the Harpoon and/or the Evolved Sea Sparrow Missile (ESSM). In fact, what has happened is that the US offers for two major Finnish naval programs have become open knowledge. This happened as the US Defense Security Cooperation Agency has requested clearance for the sale of 112 RGM-84Q-4 Harpoon Block II+ ER anti-ship missiles (of which twelve are of the older RGM-84L-4 Harpoon Block II version which will be upgraded) and 68 ESSM missiles. These kinds of pre-clearances are not uncommon, and allow for a rapid deal following a (potential) procurement decision by a foreign customer (thanks to Aaron Mehta for providing insights about US export).

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One of the latest renders, showing the refined corvette concept. Source: Finnish Defence Forces / Insinööriupseeriliitto

The background is two ongoing Finnish projects: the Pohjanmaa-class multirole corvettes and the PTO 2020 heavy surface-to-surface missile. The PTO 2020 will be found aboard the Pohjanmaa-class as well as replacing the current MTO 85M (roughly a RBS 15 Mk II) on the Hamina-class as part of their MLU as well as in truck-mounted batteries. As the MLU for the Hamina is very much underway already, the winner of the PTO 2020 will be announced during the first half of this year. I am still standing by my opinion that the RBS 15 Mk 3+ and the NSM are the two frontrunners, and would be somewhat surprised if Harpoon won the trophy (and even more so if the Exocet MM40 Block 3 did, though everything is possible).

The Pohjanmaa-class is still in the design stage, with the main contract(s) to be signed this year, and the building phase to start next year. The armament shown on renders include two quadruple mounts of PTO 2020 amidships, the new lightweight torpedo from Saab, the BAE/Bofors 57 mm Mk II deck-gun, and a battery of vertical launch system-cells (VLS). The two main VLS-systems on the market are the French Sylver and the US Mk 41 (a modernized version called Mk 57 is also available, and mounted on the Zumwalt-class). Both are available in different lengths, with the shortest Sylver, the A43 (an earlier A35 concept seems to have been dropped), being around 4.3 m long (or rather, high), and the shortest Mk 41 being 5.2 m long. The 8-cell module of the Sylver is also smaller and lighter than the corresponding 8-cell Mk 41 module, in part because the silos themselves are a few centimeters smaller. For a full run-through of the differences, see this post by the UK Armed Forces Commentary-blog, where the differences are discussed with a keen eye to the pros and cons for the British Type 26 Frigate.

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An ESSM leaving a Mk 41 cell. Source: US Navy via Wikimedia Commons

Now, while some vessels, such as the current Finnish Hamina-class and the upcoming British Type 26, feature dedicated cells to their main air-defence assets, the VLS on the Pohjanmaa will likely be home to the ships main air defence weapons. This becomes evident as the ESSM offer is for the weapon quad-packed in Mk 25 modules, designed to fit the Mk 41-system. If the ESSM would be chosen, the Pohjanmaa-class would be by far the smallest vessel to feature the system. The decision to offer the Mk 41 is interesting, as there is a dedicated Mk 56 ESSM VLS-system if the sole use would be for the ESSM.

The ESSM is certainly a competent weapon, and shows what the Navy is aiming for. 8-16 cells with quad packs would provide for 32-64 medium-ranged missiles, a huge boost compared to the current 8 short-range Umkhontos found on the Hamina. While the Mk 41 is too big for the Hamina, the Mk 56 mean that half a dozen ESSM’s could potentially be fitted as part of the MLU if the Navy choose to go down that (unlikely) route. More interesting is that the ESSM could be fired from the Army’s NASAMS surface-to-air batteries, letting the Navy and Army use the same missile stock. The upcoming ESSM Block 2 will feature an active seeker based on that of the AMRAAM, and is potentially the version offered to the Pohjanmaa.

Interestingly, the AMRAAM-ER is a AMRAAM married to the engine of the ESSM, and no, I don’t know what exactly is the difference between an AMRAAM seeker married to an ESSM engine and an ESSM engine married to an AMRAAM seeker.

I am still inclined to believe that the Sylver might be the Navy’s preferred VLS due to the smaller footprint. However, as with the PTO 2020, we will just have to wait and see.