The Coastal Jaeger Battlegroup need the Navy Nemo.
That’s the short version of the story. Acquiring the Patria Navy Nemo advanced mortar system mounted on a small vessel that can keep up with the other crafts used by the Coastal Jaeger Battlegroup is exactly the kind of force multiplier that is needed if today’s slimmed version of the Finnish Defence Forces is to be able to not only survive but also to conduct offensive operations on the modern battlefield.
As I touched upon in my post on the Åland islands, the archipelago is a battlefield unlike any other. There is no single frontline, and anyone attempting to control all islands will soon find themselves overextended to the point where they are unable to defend against a determined attacker. Instead, the defender has to concentrate their forces on strategically important islands, from where they can then extend zones of control over the lesser ones. This creates a situation of islands becoming isolated strongholds, with periods of calm being interrupted only by raiding or outright assaults. The fighting is usually swift and brutal, taking place at extremely close ranges, and with a very limited ability to either reinforce or resupply the forces involved, or to evacuate wounded for that matter. Any retreat will usually have to take place over open water under fire, further increasing the determination to stay in the fight for both sides. To only solution for the attacker is therefore to rely on surprise to create local man- and firepower superiority on a single island, throwing the defender literally into the sea. Naturally, on a grander scale this calls for a very delicate balance between overextending and leaving gaps in the defence, with the Hanko campaign of 1941 probably being the best historical case study to shine light on the dilemmas. Here, the Finns continuously stretched their defences too thin, and despite the Soviets strategically being on the defensive, they managed to score a number of operational victories by being active, keeping the initiative, and playing on the strengths of the attacker.
In the end, it was the German Army Group North and the fall of Estonia that sealed the fate of Krasnyi Gangut, the Soviet naval base in Hanko. After it became clear that the continued value of occupying the peninsula was limited, the Soviet withdrew the forces to Leningrad to shore up their defences there.
Many things have changed since the summer of 1941, but the basic premises remain the same. The Finnish Operational Forces, the spearhead of the defense forces and the units tasked with fighting the decisive battles, include a Coastal Jaeger Battlegroup, heir to the former wartime Coastal Jaeger Battalion (RANNJP). This is the sole unit in the Finnish wartime TOE which has offensive operations in the archipelago as its main task.
The Finnish Coastal Jaeger is a light infantryman. This is natural, as the archipelago rarely sees anything heavier than what can be carried on the back of the soldiers themselves. No-one is going to drag a MBT onto an island measured in acres, and even if an IFV could potentially be a formidable adversary after having swam out, it would probably soon find itself hampered by the close quarters of the battle. However, to establish the shock and awe needed for an amphibious assault, indirect fire will play a key role. The individual companies of the battlegroup feature light mortar troops with three 81 KRH 71 Y, 81 mm light mortars, and these are carried on two landing crafts. These are relatively light, and need to be set up on a neighbouring island within 5 km of the battlefield to be able to participate in the landing. Alternatively, they can be brought onshore and support the landing from the beach, as long as the island is big enough.
But while 81 mm mortars are a handy weapon for suppressing fire, the battelgroup will need heavier rounds if it is to be able to dig up an entrenched enemy. This is where the heavy mortars come into the picture. The TOE of RANNJP featured a single mortar battery with six heavy 120 KRH 92 mortars, towed by trucks. The basic mortar is a competent if somewhat unspectacular weapon. It is able to fire HE, flare, and smoke rounds, and features a max range of approximately 7.5 km while weighing in at 500 kg in its assembled state. However, it is the sole unit in the battlegroup that is carried on trucks and not on fast landing crafts, significantly reducing its effectiveness and tactical flexibility. This is especially problematic as the archipelago is a prime area for the indirect approach, with tactics such as skipping islands and isolating enemy strongholds by cutting off their supply lines. This becomes vastly harder if any potential targets have to be within ~7 km of controlled mainland where the small convoy of trucks and mortars can pull aside and set up positions. Further complicating the problem is the fact that the once mighty Finnish coastal artillery has been reduced to a shadow of its former self, with most of the fixed installations having been disbanded and the towed pieces having been transferred to the army. In conclusion, the Coastal Jaeger Battlegroup need a organic unit that can keep up with its fast assault crafts, and which can deliver heavy and accurate indirect fire support.
Luckily, the problem isn’t new, and as mentioned Patria has had a solution ready for over a decade. Originally this centred on the joint Finnish-Swedish AMOS twin-barrelled mortar turret. This was originally planned for and tested on the Swedish CB 90 H, but the 15 m long and relatively narrow vessel proved too unstable to carry the turret, and the number of rounds carried was also limited. The Swedish forces started planning for a new vessel, SB 2010, designed around the turret, while the Finnish Navy instead focused on a lighter single-barrel version. The former was eventually destined to remain on the drawing board, while the later became the Patria Nemo, which was successfully tested on a modified Jurmo-class fast landing craft. No order was however placed, and the focus of the Finnish coastal jaegers moved from the 15 m long Jurmo to the larger and significantly more versatile 18 m Jehu-class (also known as U700-class or Watercat M18 AMC).
Compared to the Jurmo, the Jehu marks a significant step up in all-round capability, including firepower (sporting a RWS with E/O-sights and 40 mm grenade-machine gun with a coaxial 7.62 mm PKM), protection (both ballistic and NBC), and mobility. Through and through, the Jehu is simply the best vessel in its (specialised) class worldwide, and has considerable room for up-gunning in the form of weapons fitted for but not with. This includes the Nemo, where the bigger hull would remedy the space and stability issues encountered on smaller vessels.
The Nemo-Jehu is exactly what the coastal jaegers need. Here is a highly mobile system, mounted on the same hull as their primary means of transport. It allows for both direct and indirect fire, and can also fire on the move. The mortar allows for operation of all standard 120 mm rounds, and has all the niceties one can expect from a modern turreted system (quick response time, MRSI with up to five rounds, high rate of fire, full NBC protection, …). While one should always treat the marketing slogans for modern systems with a grain of salt, there’s still plenty of situations where the simple number of barrels count for more than MRSI-capability, there is little to deny that three or four Nemo-Jehu’s would offer significantly better and more flexible indirect fire support than the current setup of six towed 120 mm mortars. The only benefit provided by the later would be the fact that they are easier to replace than the highly specialized vessels.
What it comes down to is, naturally, cost. In today’s cash-strapped defence forces, there are a number of programs that are all urgent and crucial for the units in question. Still, it is hard to argue that we should invest 34 million euros in new assault crafts for the coastal jaegers, and then not go the extra mile to buy three or four additional vessels to be able to effectively support the first twelve during amphibious landings. The unit price for the first twelve Jehu’s, a program cost of 34 million euros split equally over the whole series, is roughly 2.8 million euro per boat. The Nemo-Jehu is probably in the same range, depending on the number of hulls ordered, as the engineering costs are markedly lower. The concept is already here.
The Coastal Jaeger Battlegroup need the Navy Nemo. As the major units of the navy are starting to take shape, forgetting the smaller craft could prove to be a costly mistake.
In the interest of full disclosure, the company I work for is a component supplier for the Jehu-class. All info given in this post is completely based on open sources, and represents my personal opinion only.