Thread by @nicholadrummond

THREAD ON FRIGATES & CORVETTES
Since Britain's Royal Navy acquired its fleet of Type 23 Frigates, the cost of effective anti-submarine warships has soared from around £135 million to close to £1 billion per vessel. This has reduced the number we can afford from 13 to 8.

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Much of the increased cost is due to the need for a more potent weapons mix. Type 26 will have a 127mm L54 main gun, two 30mm cannons, two Phalanx 20mm CIWS, three 8-cell Mk 41 VLS cells for Sea Ceptor SAMs, Tomahawk LAM, ASROC and LRASM and a Merlin helicopter.

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Type 26 will also have a towed array and bow sonar for submarine hunting. Its Artisan 3D radar can track 80 separate targets at 200 km. A quietened hull will reduce sonar interference when detecting submarines. These sophisticated but necessary systems add further cost.

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All in all, Type 26 global combat ships are so capable that Australia and Canada have decided to acquire them too, although some naval commentators consider them to be cruisers more than frigates. The question is whether 8 Type 26 ships is enough to fulfil our ASW tasks?

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Irrespective of ASW needs, additional surface combatants are required. The Type 31e frigate programme therefore aims to acquire 5 low-cost light frigates for non-ASW roles. So far, three designs have been shortlisted: Leander, Arrowhead 140 and a MEKO A-200 derivative.

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A Type 31e objective is to produce a vessel that costs £250 million or less. This seems ambitious given the requirement to fit Artisan radar, VLS cells for Sea Ceptor and the same FCS as Type 26. Other Light Frigates and Corvettes cost £350+ million each.

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Some think the Type 31e programme should encompass additional ASW capabilities. Others believe that even lower-spec ships without ASW equipment cannot be acquired for the proposed budget. What we can agree is that 6 Destroyers plus 8 ASW frigates is not enough.

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The Type 31e discussion clearly highlights how costs are reducing warship numbers. This isn't only a problem for the Royal Navy, but for other navies too. Globally, it has driven a new class of Corvettes with good anti-air and anti-surface weapons, but no ASW.

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Meanwhile, increased modularity of mission systems is helping to balance capability with cost. Systems like the SkyShield 35mm CIWS take-up little space and are easy to install. Vertical launch SAM cells are also useful because they can launch a variety of missile types.

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Modularity allows ships to "fitted for but not with" a variety of weapon systems. This kind of flexibility allows warships to have appropriate fits for each task. It also saves money. However, one area where greater modularity and lower costs are needed is ASW.

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Bow sonars allow submarine detection at speed, but rely on quiet hulls. Towed arrays restrict speed and can be affected by sea conditions. Could we increase ASW effectiveness and reduce cost through systems such as remote control surface drones and underwater vehicles?

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We need a naval equivalent of the M9-9B Reaper. When any warship can control a ghost fleet of multiple unmanned ASW drones, we will achieve greater coverage at lower cost. Of course, this is no substitute for absolute ship numbers.

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Something else that makes less costly warships an urgent priority is the emergence of hypersonic anti-shipping missiles. If a £1 billion warship can be sunk with a missile that costs less than £200,000, fleet attrition will be rapid. We may need a navy of small ships.

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Even without the hypersonic missile threat, the RN needs additional low-cost warships. While modular corvettes / light frigates like Type 31e can do much to augment Royal Navy fleet numbers; they're a pointless endeavour without more sailors to operate them.

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