Tuesday, November 27, 2012

Ocean Patrol Vessels to save the day

With BAE Systems making it clear that there is no job in sight for its shipyards after the work on the aircraft carriers is complete, Portsmouth is living days of well justified worries as its shipyard is the one most at risk, and closure means 1500 jobs lost, in a time of economic crisis.

To make things worse, closure of Portsmouth, the only active shipyard in England that can build complex warships could become even more of a damning issue is Scotland was to become independent with the referendum.
Not later than yesterday, in Parliament it was proudly announced that the "residual UK", left without Scotland, would have the capability to build its warships in its own yard(s). The statement was, frankly, pathetic. There is only one active yard capable to build warships, Portsmouth, and it might soon close.
As minister Peter Luff honestly admitted on Twitter, there are potentially locations and yards that could in line of principle build warships, but all of them would need development. Development means costs, and important ones at that. Where would the money come from? From additional defence cuts, probably from a further reduction in the fleet. And i'm not even getting in on the immense headache (and cost) that would come with the need to re-base the whole SSN fleet and, much more challenging, the nuclear deterrent fleet and facilities.
The prospect of having to move back to England the submarine fleet is already enough of a financial and operational nightmare in itself, without closing Portsmouth's yard to add another problem to the list.

If only for prudence, a wise government, no matter how "confident" about Scotland making the right choice, would preserve its only realistic plan B.
Not to mention, again, that in times of economic crisis closing major sources of employments is just dumb and exactly what is not needed. Particularly when MOD and BAE have signed a Terms of Business Agreement that means that the shipyards get either work orders, or money, in order to live on.
Closing the shipyard and paying for it is dumb not one but two times.

So there's who has sensibly proposed bridging the gap between the aircraft carriers work and the Type 26 by ordering a couple of Oceanic Patrol Vessels for the Royal Navy, with an investment of 150 or so million pounds. 
So far, the plan is being resisted and it has already been described as unlikely to be adopted, but it has so much merit that i truly struggle to accept that it won't be considered.

A relatively small investment such as this could greatly help the Royal Navy, providing it with two much-needed, cheap patrol vessels more adequate for some of the standing tasks at hand: OPVs would be perfect for the Caribbean and for anti-piracy patrols, as well as for the protection of the minesweepers in the Persian Gulf from the very real threat of fast attack crafts and suicide speedboats.

The "bridge" offered by the work on the two OPVs could keep Portsmouth viable well past the Scottish Referendum vote, keeping England's shipbuilding option alive in the facts and not just in empty statements.

In addition, the OPV order would keep 1500 people employed, and it might help the shipyard rebuild some international prestige and credibility, essential requisites for aiming much more aggressively to winning export orders. The sale of 3 OPVs to Brazil was great news, but even those 3 ships were available because of an export disaster. Much must be done to improve Britain's exports chances in the shipbuilding arena.

The "gap-filler" order would keep Portsmouth active until work on the Type 26 frigates starts. At that point, for many years, the british shipyards might be happily busy: it'll take over a decade to replace the Type 23 fleet (if the plan does not change, the first Type 26 should enter service around 2021, and the last Type 23 should bow out in 2036!), and around 2028 the Navy expects to replace its Hunt and Sandown minesweepers with at least 8 newbuild vessels under the MHPC program.
There's a four years gap between 2014 and 2018 that needs bridging, but assuming that the Type 26 program goes ahead as planned, after 2018 there should be work for everyone. It would be a shame not to allow Portsmouth to live on to that date.

As for the Royal Navy, would two OPVs be useful?

HMS Black Swan and HMS Starling

For the Navy, two OPVs would be great additions. The fleet is overstretched, and short of hulls. It is being asked to be present in too many places at once, and it currently lacks a credible, long-range second-tier fleet of simple, cheap patrol vessels for the more mundane tasks, such as contrast to smuggling and drug traffic and anti-piracy.

The Chief of Defence Staff General Sir David Richards recently admitted:

"One of my biggest concerns is the number of frigates and destroyers the Navy has."
“You get to this ridiculous situation where in Operation Atalanta off the Somali coast, we have £1 billion destroyers trying to sort out pirates in a little dhow with RPGs [rocket-propelled grenades] costing $50, with an outboard motor [costing] $100. That can’t be good. We’ve got to sort it out.”

The problem is that there are too few hulls in the water. There are standing tasks that are regularly met by RFA vessels more or less removed from their natural roles: i'm thinking about ships such as RFA Argus, sent to the Caribbean to patrol its waters and provide disaster relief instead of working as the hospital ship she is meant to be. The Royal Navy deployed an amphibious Task Group in the Mediterranean sea for Cougar 12, as we know, and the whole task force only had the limited medical facilities of HMS Illustrious and a makeshift hospital ward on the frigate HMS Montrose.
It is more than fine to test the ability of Montrose to deliver forward medical capability on exercise, but the navy should be able to call on its hospital ship for such deployments, not have it doing OPV work on the other side of the Atlantic.
And when it's not Argus, it's a RFA tanker, which is equally more or less removed from its intended job. 

Cougar 12, again, deployed with no RFA support vessels assigned: no tanker and no solid support ship, because there was none available. Sure, Cougar is an exercise and happens in the friendly waters of the Mediterranean, where ships can just go into a friendly port to refuel and load stores, but the RFA support vessels are not there to do OPV work: they should accompany Task Groups to enable them to stay for long periods at sea with minimum to no support from the shore. And the major exercise the RN faces in one year should never happen without testing and exercising the ability to sustain the fleet out at sea with the RFA's ships.

Cougar 12, again, put to sea an amphibious task group without a single air defence destroyer, but just two frigates with short-range missiles, one of which has then left the task group to head into the Gulf to take over the patrol role there.

The Royal Navy lost to cuts one of the invaluable Bay-class ships as well. Fundamental to enable the UK's amphibious capability, the 3 remaining vessels are never really available for their role as amphibious transports, because one is constantly in the Gulf working as "Sea Base" for the command and sustainment of the mine countermeasures fleet in Bahrain.
Add to that the awareness that another of the two remaining is likely to be in refit after spending two years in the Gulf, and the amphibious force deploying to the Mediterranean manages to bring along only 1 Bay.  

And we should not forget that Cougar 12 is, of course, a training deployment planned months before it started, but it is at the same time a temporary forward basing of the UK's premium rapid reaction force. The Response Force Task Group of the Royal Navy uses Cougar to prepare itself for war, but while it is at sea it is at Very High Readiness to deploy for military operations. Last year it was Libya, this year it is Sirya, and the next place is not yet known.
Training exercise, sure, but also first available tool to respond to crisis, so the Task Group should be as capable and "warlike" as possible. And this year's Task Force wasn't at its best, to say the least. 

These are all alarming signals. There are not enough high-end and specialised vessels to do the job, partly because there is just too few ships, and partly because many of those which are available are being used in the wrong way because there is not a second-line of ships.

The frigates that Nelson notoriously wanted in greater numbers were not the frigates of today. They were lower-rank vessels, meant to operate widely dispersed, on a variety of tasks, while the capital ships - the big ships of the line such as HMS Victory - were the big fist meant to knock the enemy down.

Today's frigates and destroyers are the Ships of the Line and Nelson's frigates are OPVs, corvettes and small, cheap warships. To be clear: the place of the Type 45 destroyer is not in the sea in front of Somalia to chase pirate boats, but it is at the flank of HMS Illustrious in the middle of the Cougar 12 task group. Or at the side of HMS Ocean near Libya last year. Or in the Gulf, where the situation can get hot very quickly and the other vessels in the area could suddenly need protection. 

This is where OPVs step in. The OPV goes to the Caribbean, or to Somalia, and lets the warships do their actual job.

Building two OPVs (two truly excellent names would be HMS Black Swan and HMS Starling, if i may suggest even the names...!) and forward-basing them (like HMS Clyde, which is permanently assigned to protection of the Falklands) would take quite some heat away from the overstretched fleet of frigates and destroyers.

One ideal location for a forward-based OPV is the Caribbean. The Royal Navy in this area delivers two main effects:

- Counter Narcotics and Terrorism (CNT)
- Humanitarian Assistance and Disaster Relief (HADR)

To face these missions, the vessels deploying to the area are normally assigned a Lynx helicopter with its complement of 12 to 15 men (including two Royal Marines heli-snipers) and a 20-man specialised HADR team of Royal Navy personnel, to whom 30 men from the core crew of the RFA vessel at hand provide support. 

A good OPV, forward-based in the area, is better suited than a tanker to CNT role, and being permanently based in the area it relieves the navy from the pressure of having to rotate ships in and out of the Caribbean, releasing vessels such as Argus and tankers that can so better focus on supporting the fleet in their intended roles.
Crews and Lynx personnel can rotate every six months, reaching the Caribbean by airplane and taking over the vessel for the successive period. During the Hurricane Season, the HADR team can fly from the UK to the Caribbean and join the ship.

What the OPV needs to have is:

- Good endurance (both in terms of fuel, and thus of range, and in terms of stores and supplies for the crew): the UK needs its OPVs far away from the home waters, so it needs them long-legged. They must not become a nuissance, needing excessive support from RFA support ships: they must work on their own as much as possible. 
- An hangar sized for a Lynx / Wildcat helicopter. An helicopter is fundamental to almost all missions, and a hangar for its recovery and maintenance is very much needed.
- Good accommodations for a sizeable additional force embarking for HADR operations or other roles
- Ideally, space for at least a couple of standard TEU containers for additional supplies and material for disaster relief and other roles.

The second OPV could be forward based in Bahrain, like the minesweepers, and from there provide security all the way down to Somalia's waters.
It would be fantastic if the OPV could support and command the minesweepers fleet and release the Bay LSD for its intended amphibious role, but this might prove impossible: the Bay, after all, is a wonderfully capable 16.000 tons ship with a well deck, a huge cargo capacity, good sensors and communications and a very large helicopter deck. A true sea-base. A 2000 tons OPV would never match the possible output of a Bay.
However, the OPV would offer better speed, an hangar for the helicopter (the Bay LSDs do not have one) and possibly a sensors and communications fit just as good as that of the LSD, so perhaps it wouldn't be totally impossible to release the Bay.

The US Navy has converted the USS Ponce, an old LPD, into a sea-base for supporting mine-countermeasure and boat operations in the gulf and elsewhere, but the UK cannot afford the luxury of such a path. Nor can it afford to continue depleting its precious amphibious power projection option by "wasting" one of its few amphibious ships in the Gulf.
Perhaps the OPV in this particular case is not the answer, but a converted civilian ship could make a cheap and effective sea base: the UK used to be very, very good at modifying civilian vessels quickly. Two examples are still in service, after being prepared for action as far back as 1982, when the Falklands War raged: RFA Diligence and RFA Argus, both unique and invaluable within the fleet.
The Royal Navy should not shy away from the option of adapting a commercial vessel to the military role, when and where this is possible, because the first way to solve the problems of the navy is ensuring that the warships available are all used in their intended roles, and are available when and where needed.

In any case, the OPVs could certainly help the Royal Navy and the UK.
And another certainty is that getting rid of RFA Largs Bay was very, very stupid.


Friday, November 23, 2012

"Largely unchanged"

I've had a Twitter exchange with Craig Hoyle, from Flightglobal.com: he has recently interviewed the British Army's Apache force commander on what the future holds for the two Attack Helicopter regiments in the AAC.
Future that, it is worth reminding it, in the Army 2020 presentation is described in this way:

Immediately, rumors circulated that, from internal briefings, the reality emerging was a tad different. Already months ago i had heard that the regimental HQs of 3rd and 4th Regiment would pretty much merge in a single command. Acceptable, overall.
Less amusing was the rumor of one frontline squadron being cut from the force. I reported about the rumor on Twitter and probably mentioned it in some of my earlier posts about Army 2020, but i was unable to obtain solid evidence, and it just felt so demented and implausible that i kept quiet about the matter.

Next week, Craig Hoyle will reveal the details he's had in the interview with the commanders, explaining the current foreseen way ahead for the Apache forces, included the thinking going on about the Apache Capability Sustainment Programme to be launched in the coming years.
But when he announced his article and specified "squadron numbers" would be a part of the talk, i couldn't help but ask:

Impatiently waiting to read your piece on the british Apaches. Is it true that one Squadron will be disbanded?
The answer was a true blow to my morale and opinion about the Army, the government and the Army 2020 "plan": 

Sorry - mission creep due to World Air Forces directory work! AH story now for mag next week, but yes, will be 4 op sqns.
My italian blood makes me be a little bit too direct at times, so my immediate reply was:

That's a cut of 2 squadrons, no less! Are they entirely crazy???

To clarify - 4 operational and the 5th as an OCU. Will also update re upgrade intentions - will be worth the wait ;)
I understand, but there are now 6 operational squadrons plus OCU, so it's a cut of two operational squadrons!
I got the impression that the 6th isn't really there, as intro plans were affected by Afghan commitments. Will check!

I have no information at the moment on the effective state of readiness of the sixth frontline squadron, and it well might be that it isn't really operational yet, with the Apache force's build-up affected as it was by Afghanistan operations.

EDIT: i went checking on EAGLE, the publication of the Army Air Corps, and from what i read there, all squadrons are definitely active, and all six have seen their share of action in Afghanistan. 

The current force structure for the Apache force is:

673 Squadron, 7 (Training) Regiment - this squadron converts pilots to the Apache and prepares them for active service in the frontline squadrons. It is the OCU for the Apache fleet.

There are then the 2 Attack Helicopter regiments, 3rd and 4th, which are both structured on 3 frontline squadrons. These should be:

4th Regiment

654 Sqn
656 Sqn - possibly the most famous Apache squadron, for a number of reasons: first squadron of Apaches to become operational, 2004, first Apache squadron going at sea on Royal Navy ships, in 2005, and first Apache squadron deploying to Afghanistan, in 2006. In Afghanistan it earned two MCs and two DFCs. It fought in Libya last year.
664 Sqn - said to have a "special relationship", like 656 with the Navy, but with the Special Forces instead. Obviously, whatever relates to SF roles is kept very quiet. It trained hard to replace 656 on HMS Ocean for operations in Libya last year, but the war was over before they could get in action.  

3rd Regiment

653 Sqn
662 Sqn - Prince Harry is deployed in Afghanistan with this Squadron.
663 Sqn

The two attack regiments command the Afghan operations for one year each, alternating in the role.  During the year of responsibility of a Regiment, its 3 squadrons deploy in theatre for tours of 4 months. In the following 12-month period, the other regiment takes over with its own squadrons.
In the meanwhile, the regiment in the UK will normally be expected to provide helicopters to the Airborne Task Force from 16 Air Assault Brigade and it will also provide a package of Apache and crews for the Response Force Task Group made up by the Royal Marines and Royal Navy.
The force, in other words, is always very busy and high in demand. 

In themselves, the present Attack Regiments are the result of at least a couple of earlier plan changes: the first due to an order for 67 Apaches against over 90 envisaged earlier (would have given a force of 9 frontline squadrons, 8 for the Army and 1 for the Royal Marines, as it was envisaged that Apache would replace the TOW-armed Lynx AH7 in 847 Naval Air Squadron, Commando Helicopter Force).
The second change was one of basing and distribution: it was earlier planned that the AAC would organize 3 Attack Regiments, each comprising 2x Apache Squadrons and 1x Lynx RECCE/Light Utility squadron.
While the force was being built up, however, it was deemed more efficient to put all Lynx squadrons in the same regiment and base (9th Regiment, which will now vanish as part of Army 2020 cuts, merging with 1st Regiment. The base is Dishfort, which will very possibly close since 1st Regiment will re-locate to Yeovilton), and do the same with the Apaches, forming two Attack Regiments at Wattisham.

Now, from the info that Craig Hoyle has obtained, we look ahead to a four squadron force, plus OCU. A cut of 2 frontline squadrons from now.
A cut hidded by a shameful, ridiculous, false "largely unchanged" claim.

Keep an eye on Flightglobal next week (indeed, it is a good source of info everyday!) for getting the full interview with the whole story. I sure look forwards to it myself, to learn about the planned upgrade at least.
And to see what impact the loss of two squadrons will have on the number of available pilots and helicopters. One would hope that, at least, the squadrons will be enlarged from current 8 airframes.

But, seen how Army 2020 has gone so far, i will probably only get angrier and even more disappointed when i read in. It truly is depressing to see that, no matter how useful and necessary a tool proves, the wild, blind axeman hits it and chops pieces off it.

And this "largely unchanged" adds insult to injury. Seriously, whoever wrote that deserves to be punched hard in the face.
It should leave it "largely unchanged" too, after all. 


Monday, November 12, 2012

Return of the airships?

The Royal Navy has not had any airship for a long, long time now, but not so long ago the national  press reported that Hybrid Air Vehicles which is under contract to build the Long Endurance Multi-intelligence Vehicle  surveillance airship for the US Army, had started talks with the Royal Navy.

At the time the report caused quite some surprise and excitement. Of course, i wasn't excluded. I reported about the possibilities rather extensively in the past, but i also reported about some of my doubts and issues with the concept.
In particular, i was puzzled by how such a massive airship would be sustained during long overhead surveillance operations far out at sea. With the limited information available at the time, i was worried that the airship probably would need a dedicate support vessel in order to be able to stay out at sea for a long time. Maintenance, refuelling, topping up of Helium, were all challenging aspects, considering that the Airlander 50 is more than 120 meters long, and perhaps 65 meters wide. You can't land it on a ship, not even on CVF. Yes, it lands on water, but when it is landed, what kind of maintenance does it need? What kind of impact the weather and rough seas will have on the ship once it lands in the water? Will it be possible to moor it alongside a RFA vessel, or another ship, and service it safely that way?

These were some of the questiones that immediately came up to me. 

Now, the Airlander 50's page on Hybrid Air Vehicles' website has been updated to include a few interesting details that partially answer mine (and, no doubt, the Royal Navy's) questions.

Hybrid claims that the Airlander 50: 

With proven low vulnerability and ability to land on water, the Airlander 50 can be maintained from on-board for an extensive period – up to several months. It is crewed and operated like a ship; crew are permanently embarked, and it is designed to accompany task forces as a unit in its own right. AIRLANDER 50 can take fuel from ships using helicopter in-flight refuelling (HIFR) facilities, load stores, food and change individual crew members if required. 

Its use with a maritime task force is something between a number of freight moving helicopters, RFA ships freight and people movement between forward mounting bases and the task group, then delivery around the task group, and even surveillance if required. With a capability to lift 20 tons vertically, AIRLANDER - 50 can be used to transfer exceptional loads between ships at sea. In assault operations, AIRLANDER can be used in support, releasing other assets, such as helicopters, to be deployed elsewhere.

This is a new information, and particularly relevant. The capability to deploy with a naval task group and stick to it, staying with the ships, is crucial to making the airship a truly useful ISTAR platform. If it was effectively demonstrated that the airship could deploy and stay out at sea with the fleet for at least 160 to 200 days, then the airship would truly be an alternative to helicopter-based CROWSNEST solutions. The airship would be a very good AEW and EO/IR surveillance platform in that case.

My doubts actually were not so much about fuel, but more about more complex and "exotic" things such as topping up of Helium, something the current warships do not do and are not kitted for, but Hybrid's claim reassures me that the problem is far from unsolvable. At least in theory.
The airship is described as having an endurance of 5 days at 16.000 feet if a human crew is on board, while it can stay in the air for a surveillance mission for up to 21 days at 20.000 feet, at an operating radium of 500 nautical miles if remotely piloted. 

With its ability to land on water, and take fuel aboard while hovering like an helicopter behind a warship, the Airlander 50 should thus be genuinely sustainable in the long term during a deployment far away from home out at sea.

In Carrier On-board Delivery (COD) role, the airship has a very interesting capability: it comes fitted with a very powerful crane that can vertically lift or lower a 20' container, loaded to a total weight of up to 20 tons.
This makes the airship a truly unmatched heavy lift asset. Sure, huge as it is, when the airship hovers over the back of a CVF to carefully lower a heavy load on deck, the air operations will be seriously affected, but the capability is very, very interesting.

The payload area of the Airlander 50 is sized to take 6 20' containers in two rows of 3 each, sitting abreast, for a total payload of 50 tons. There is also a secondary cargo area, 2.8 m high, 3.93 m wide and 10 m long, which can prove very useful for many uses, including providing a rest area for the human crew when present.
The containerized cargo area is particularly useful, as almost anything can be built into containers, and an airship like this could deliver a small but effective containerized hospital directly to a disaster struck area or rear line in exceptionally short time, and/or deliver workshops and Fitter Sections directly from the amphibious ships to the front line. For example, the british armed forces already have a series of containerized medical facilities including shelter-mounted CT scanners, 44 container workshops and REME repair posts
Deploying containers by air, vertically and without the need for an airport, is in itself an immense operational advantage.

Another interesting aspect of the Airlander, which i suspect is however still largely to be explored, is shown in one image from Hybrid, in which an airship can be seen towing a sonar in the water. It would be interesting to explore this aspect further, because such an airship could be an excellent ASW weapon and a good maritime patrol aircraft, with an important operating radius. The Airlander is said to have a range of 2600 nautical miles (not clear if it is at full 50 tons payload, however). Of course, flying low over the waters to search for submarines and tow a sonar curtain will have a big impact on the operating radius, but it should nonetheless remain impressive.

There are surely aspects and procedures to be studied and determined, but the use of Airships in support of military operations, including at sea, promises to deliver serious advantages.
It is definitely an area where i'd like to see the UK investing. I think there is room for achieving great results.

Friday, November 9, 2012

Aiming for the Whole Force - UPDATE

The Ministry of Defence has launched yesterday the Consultation on the future of the armed forces reserves, aiming to collect the information needed to prepare a Report for publishing in Spring 2013. The target is to deliver the Whole Force concept, integrating Regulars and Reserves in a responsive, modern force. It is not an easy target. Much could go wrong. But i was pleased to see clarity of thought in the consultation paper, which is, at least, promising.

The Reserves are to be significantly grown in number and, even more complex, in trained strenght. The figures provided are particularly interesting and telling:

Maritime Reserves (Navy and Marines)

From 2526 All-Ranks now, the reserve is meant to expand to 4150 by 2020, with a trained strenght of 3100.

Royal Auxiliary Air Force

From 1335 All-Ranks now, to 2300 by 2020, 1800 of which trained.

Territorial Army

From 25.430 now, to 38.000 by 2020, with a Phase 2 Trained Strenght of 30.000.

The expansion of the Royal Auxiliary Air Force includes the standing up of 5 new Squadrons:

No 502(Ulster) Squadron at JHC Station Aldergrove;
611(West Lancashire) Squadron in Liverpool
614(West Glamorgan) Squadron in South Wales, most likely at RAF St Athan.

These squadrons will be general service support squadrons representing various trades and branches from within the RAF.
At RAF Brize Norton in Oxfordshire, 2624(County of Oxford) Squadron will re-form in the force protection role and 622 Squadron will stand-up as the Reserve unit for aircrew augmenting the RAF’s air mobility force.

It must be noted, however, that the RAF anticipates the disbandment of a couple of Field Squadrons from the RAF Regiment (from 8 to 6) after Afghanistan operations will be over, and this change might be accompanied by a reorganization of the Reserve Force Protection squadrons as well.

The most crucial and challenging development is that of the Territorial Army, which will see a lot of changes. It is indeed proposed that even its name will change, to Army Reserve, as "Territorial" is seen as a limiting, unfair description for a force destined to much more frequently train and operate abroad.

It is expected that the force structure and basing of the Reserves will change, as much as possible within a budget that remains tight, to enable the desidered "pairing" of regular and reserve formations, which will be crucial to the future of the Army.
In this sense, Philip Hammond said he hopes to deliver to the House the report on the full plan for the basing of the Regulars (a chapter of Army 2020 that has been left quite up into the air in the previous announcements) before Christmas, so that work can then start on the plan for the Reserves, with the hope of concluding the process in time for the Reserves Report publication in Spring 2013.

The Basing Plan, if delivered in one single go, will not be just about the Army, either, as there are still question marks over the future of RAF aircraft fleets and related bases. We might see confirmed the selection of Marham as future Main Operating Base for the F35 fleet, for example, and there have been rumors of a possible rethink about the transfer of Typhoon from Leuchars to Lossiemouth, especially if the Typhoon Tranche 1 fleet is retained and a 7-squadron force is adopted.

As part of the modernization of the Army reserves, the TA is being given more up-to-date equipment to train and operate with. Since last October (and out to December 2013), the Yeomanry regiments are being given a first tranche of 80 Land Rover RWIMIK. In fact, as you will remember from the Army 2020 plan, 3 of four Yeomanry regiments of the reserve are to become Light Cavalry formations, with the 4th regiment in Tank Crew Replacement role, supporting the Challenger II fleet.

Some 800 Land Rover Wolf and 900 MAN SV trucks of all types are being passed to the Reserves, with deliveries completed by December 2012 and March 2013 respectively.

By March 2013 the Reserves will be fully issued with the new MTP clothing and uniforms, and they will also be assigned stocks of Dismounted Close Combat equipment, including FIST STA weapon sights, night vision googles, body armour and other kit.

This is part of a 1.2 billion investment, including a first allocation of four million pounds for improving a selected net of Army Reserve Centres by April 2013.
Crucially, Oversea Training Exercises (OTX) have returned, with several having already taken place, such as Ex Roman Star, in Italy.  

The Reserves Consultation Paper says that mandated training periods for the reserves will change for the TA, with an additional 5 days per year (from 35 to 40), following completition of initial training. 16 of these 40 days are delivered as a continuous period of training, while the others are delivered through weekend and evening training sessions, to minimise the burden on employers.

The Royal Navy Reserves are expected to continue with their 25 days training requirement, with 35 days for Marines Reserves and for Royal Auxiliary Air Force personnel.
Naval Reserves are quite frequently called into action as of now. The Maritime Reserve is, indeed, highlighted as example of integration, being considerably ahead of its counterparts.

Indicatively, Maritime Reservists can expect a minimum notice of 28 days when called out for a contingency operation, and a 60 days notice when they are called up for routine deployments.
Indicatively, they will be expected to have one 6-month long deployment every 5 years.

RAuxAF personnel could be called into action for up to six months every 3 years, but normally they are employed for much shorter periods, the report says.

The Army Reserves's deployment cycle will be particularly crucial, as it will be indispensable to use large numbers of Reserves to sustain future enduring operations. The report acknowledges that from a 10 to 15% share of Reservists in a brigade-sized deployment abroad, the Army will move to a 40% share of Reserves by the time of the 4th and 5th Brigade tournations in theatre.

To sustain this, it is envisaged that, one year every five, an Army reservist will be at a minimum readiness level of 3 months notice. Of these three months, up to 8 weeks could be taken up by pre-deployment training, so the effective notice might be as little as a month. A 6-month deployment would follow.
In practice, an Army reservist could expect to be mobilised for up to 1 year every five, with the 12 months including the pre-deployment training, the tour itself and a period of rest and recovery afterwards.

This 5-year availability cycle will cohexist with the Army's three year training and readiness cycle, as described in the Consultation Paper.

In Year 1 of this training cycle, a Reserve battalion will conduct a basic level of training, to get its soldiers used to working as a team under pressure. The training will culminate in a 16-day exercise held in the UK, where the soldiers will practice their individual skills and their ability to work together. This is mandated training and must be attended by the reservists. It will be planned well in advance and every effort will be made to stage it outside normal working hours to help reservists and employers absorb the impact.
Year 2, Platoon-level training will take place during weekend field exercises, some of which will involve working with regular soldiers. The year will see a large 16-days long oversea training exercise, possibly to Kenya, certainly along with the Paired Regular formation accompanying.
In Year 3, the reserve battalion might be asked to deploy on operations, possibly fielding formed
sub-units alongside the regular counterparts.

The pairing of Regular and Reserve battalions presents geographic challenges, hopefully to be tackled by the Basing reviews, but it might also mean that additional Reserve formations will be created, depending on how exactly the pairing will work. An interesting point was made in Parliament about the possibility of tapping into the large number of willing Gurkhas that would gladly join: Hammond said that he's not currently aware of a plan for a Reserve Gurkha battalion.
I, however, think it is actually a good idea, at least because Gurkhas willing to join are numerous, and it would be a good way to help with reaching the challenging manning targets. 

Hammond however hints that Logistic, REME and Engineer reserve formations will get the most attention, saying that the army took a "deliberate decision has been taken to reduce manpower disproportionately in logistics, engineers and REME, which will require a disproportionate growth in the reserve strength in those three areas."
A previous Reserves paper also highlighted Light Gun artillery as a field good for increased use of Reservists.
There has also been talk about a new Army Air Corps reserve squadron, 666 Sqn, to stand up as a Wildcat reserve formation at Yeovilton as part of 6 Regiment. 

We will see how the plan will or will not follow these indications.


the autumn issue of ARQ, the british army reserves magazine, includes a page spelling out the roles currently envisaged for the Reserve units in the new, integrated force.
It is not clear how "definitive" this is, but it is interesting to see it nonetheless. Contrarily to earlier indications, the number of Light Gun artillery regiments is seen decreasing (from 3 to 2), while the GMLRS and STA components are seen growing, from 2 batteries of each specialty in the same regiments (101(V) Regt) to two separate regiments, one with GMLRS and one in the Surveillance and Target Acquisition role.

Anyway, here is the graphic as appeared on ARQ

The ARQ page

The Infantry is not seen changing, and i am a bit surprised by this, as in my opinion there is not enough battalions at the moment to enable proper "pairing". One battalion is seen in Air Assault role, and i think it will be 4 PARA, which has already been assigned to the Joint Helicopter Command.
2nd Royal Irish regiment was also moved under JHC control, but probably this second move is going to be reversed and the Royal Irish involvment in 16AA brigade will end. 
The remaining 13 infantry battalions will have to be paired with, according to the Army 2020 document, up to 20 regular battalions (14 Light Role plus 6 Light Mechanized formations on Foxhound vehicles). Even if the 2 Gurkha battalions will have no reserve counterpart, the Reserve battalions look too few at the moment.

The Armour component also presents no surprises, sticking to what was announced by Army 2020: 3 Light Cavalry/RECCE regiments and one Tank Crew replacement regiment. 

The Army Air Corps reserve component is also seen staying formed by one Regiment, the 6th, and there is no way for now to know if the additional Squadron will be there or not.

The Royal Artillery component, as noted earlier, is going to change.

The single Close Air Defence regiment (106(V) Regt, i don't think it'll change) will remain, but for what i've heard it will lose the Rapier component and only work with Starstreak.

The current 3 Light Gun regiments (100, 103, 105) will become only 2 despite earlier indications suggesting a growth.

101(V) Regiment will have one of its two roles assigned to another formation. It currently has 2x STA batteries and 2x MLRS battery, while under Army 2020 there will be 1x MLRS Regiment and 1x STA regiment. Probably the second regiment will be the missing Light Gun formation, re-roled.

The UAV regiment is staying. Even if ARQ doesn't say it, i'd assume there will be no change, and it'll be 104(V), as now. 

In support of my expectations, i can report that 101, 104 and 106 regiments were moved under Theatre Troops in the past months.

The Royal Engineers reserves will provide 4 Close Support Squadrons, 3 Force Support Regiments, 4 Search Squadrons, 1 Works Group, 1 Geographic Squadron and 3 Specialist Team Royal Engineers.

The identity of two of the Force Support regiments is already pretty much certain: 71 and 73 Regiment have been moved in recent times under Theatre Troops.

The 4 Search Squadrons shoud be part of the "integrated" 101 and 33 EOD Regiments. I think there are only 3 reserve squadrons in the two regiments as of now, so there will be a growth here.

The 4 Close Support Squadrons should include 131 Indipendent Commando Squadron, perhaps 591 Indipendent Squadron, which is the only RE unit left in Northern Ireland, and 299 Squadron (Parachute). The other squadron will probably be the remaining part of a Regiment that will be lost, as the royal engineers reserve currently also lines the regiments 72, 75 and Royal Monmoutshire. For what we can understand from ARQ's presentation, it is likely that only one of these three regiments will survive, as the third Force Support regiment. There is no mention of other regiments, so that would imply the disbandment of two remaining formations. The Royal Monmoutshire identity is likely to be protected somehow, basing my reasoning on seniority.
The situation here is a bit murky still. It seems, however, that even in times of growth for the Reserves, there will be formations lost. 

The Royal Signals will apparently lose a regiment as well, from 5 down to 4. I suppose, but cannot be sure for now, that the 3 squadrons remaining will be the same as now, with 43 Sqn specialized in aviation support, 81 Sqn in telecommunications support and 63 Sqn in support to SAS operations.

The Royal Logistic Corps are listed with 5x Transport Regiments (down from 9, a loss of 4!), 2x Supply Regiments (same),  1x Postal and Courier and Movement Regiment (apparently the result of merging the roles of the current 88 (P&C) and 162 (Movement Control) Regiments), 1x Fuel Support Regiment (a new creation which will probably include the current 383 Commando Petroleum Troop), 1x Port and Maritime Regiment (same) and 1x Catering Support Regiment (same).

Judging from the ARQ overview, the RLC reserve component is due to take a tremendous blow, regardless of the manning increase for the reserve. There is also no mention in ARQ of the single Pioneer Regiment, and since the only regular unit in the same role has been closed with the specialty no longer deemed necessary, i suspect its reserve will follow and be disbanded.

A loss of 5 regiments, it would appear.

In the medical field, ARQ reports: 1x Air Assault Medical Squadron (same), 4 Medical Squadrons in the Adaptive Force (1 should be new, while 3 squadrons are already part of the regular Medical Regiments), 10 Field Hospitals (same), 1 Hospital Support Regiment (same), 3 Medical Regiments (same) and 1 MEDEVAC Group (currently is a regiment, how will the change work?).

The REME component shows a total of 6 Force Support battalions (a growth of 2, but inclusive of 101 Battalion which is to lose its current regular component and pass wholly to the reserve).

The Royal Military Police component seems set to lose a Company: from 4 plus the Special Investigations company to 3 plus special.

Two Reserve Military Working Dog Squadrons are to be formed (unless it is two of the five regular squadrons that get transfered to the reserves...). 

And the Military Intelligence battalions are to grow from 2 to 4, with a Specialist Military Intelligence Company in addition.

In general, it is not so much of an exciting plan. Looking at it and at the current force structure, you wouldn't exactly tell that the force is expanding.
Coupled with the fact that the ambitions in terms of trained strenght are very high, i'm more than a bit worried in front of this plan. I'll be looking forwards to the release of more details. And honestly, i expect some changes to the above scenario, personally.

It will be crucial to get this ample program of changes to the Reserves right. I will continue to follow with attention the developments.

Tuesday, November 6, 2012

Successor Submarine and Alternatives

There are countless things that can and should be said about the much discussed plan for the sustainment (not replacement, as is incorrectly said all the time) of the Trident missile system.
Overall, there seem to be agreement on the fact that submarines remain the best platforms for the deterrent, with no one questioning the long demonstrated rationale of moving away from an Air Launched deterrent with fleets of strategic bombers and tanker aircrafts. No one, unsurprisingly, is arguing for a solution made up by silos on land. There’s a current that calls for outright nuclear disarmament, but this option in my opinion is not even worth exploring, and then there is the famous “review of the alternatives” sponsored by the LibDems.  

I thought I would write my own quick review, mostly technical, of the possibilities of adopting an “alternative” and ideally cheaper submarine-based deterrent.
In the past, I wrote a wider analysis and report about the Trident situation, including a comparison of national Nuclear Doctrines, which shows, for example, that France’s nuclear policy is one of the most aggressive ones, while China’s official position is, at least for now, remarkably similar to the UK’s one.
That earlier, large review remains valid, so it is worth a look into, here.

First of all, what exactly are we talking about?

There seems to be a quite widespread ignorance of what program the MOD is currently trying to tackle. The heated debate over the nuclear deterrent has contributed to bring politics all over the matter, making it confused and painting a picture of the situation that is often unclear at best.

The nuclear deterrent is composed of these main components:

Trident II D5 is the missile/weapon system. It is not going anywhere at least until 2042, when it -might- be replaced by a new missile development, indicated, i don't know how reliably, with the name Trident II E6. With the recent test launch from HMS Vigilant, the Trident missile has logged in 143 consecutive succesfull, flawless launches. So it makes sense to assume that, more than a replacement, the next missile will be a technology refresh largely based on the already available material. In any case, what the UK is wrestling with at the moment is NOT a replacement for the Trident missile system. 
For the UK, Trident II is a bargain, as it purchased the rights to 58 Trident missiles under the Polaris Sales Agreement (modified for Trident) from a jointly maintained "pool" of missiles that arms both the british and the US Atlantic SSBN fleets. These missiles are fitted with UK-built warheads and are exchanged when requiring maintenance. Under the terms of the agreement, the United States does not have any veto on the use of British nuclear weapons. Some of the Trident missiles originally acquired have been fired in test launches, so the Vanguard submarines have never (and will never) have all of their tubes filled with missiles.
In fact, while the theoretical capacity of the four Vanguard-class submarines is 64 missiles and 768 warheads (16 missiles for each submarine, each missile carrying up to 12 warheads), only 58 missiles were leased and some of these have been expended in test firings. The UK leases the missiles but they are pooled with the Atlantic squadron of the USN Ohio SSBNs at King's Bay, Georgia (previously the UK maintained its Polaris missiles in-country).
The nuclear warheads themselves are instead UK-made, from design to assembly to maintenance to preserve the independence of the deterrent.  This work is done at the Atomic Weapons Establishment (AWE) in Aldermaston.

The nuclear warheads carried on Trident are also due to live on for many more years, with a replacement not envisaged before “the late 2030s” and possibly further onwards, out to 2042, after in 2010 the UK accessed technology being used by the US to extend the life of their own warheads and increase their accuracy to enable more effective targeting of hard and deeply buried point targets. 
The US warhead is the W-76-1, and the british one is presumably a national development of said weapon.
It is anticipated that developing a new warhead when the current ones will have reached the end of their safe and useful life will cost 2 or 3 billions. As part of cooperation with France, the two countries are working together to ensure the safety and effectiveness of their nuclear warheads: considerable savings have been achieved by deciding that the complex computer simulations needed to ensure the safety of the nuclear warheads (since live nuclear tests are notoriously banned) will be carried out in France, at Valduc, near Dijon, from 2015 onwards. A new, modern facility is being prepared for this, under the name EPURE, specialized in the study of the complex hydrodynamics connected to a nuclear explosion (solid materials behave like liquids when subject to the extreme levels of pressure and shock of a nuclear detonation). The british Atomic Weapon Establishment will take on the role of developing new technology in exchange, with the creation of a Joint Technology Development Centre which will develop advanced instruments for EPURE itself. This has relieved each country from the need to invest several more billions. The UK, for example, would have had to invest billions in the Hydrus, a new hydrodynamics test facility at AWE, that now will not be.

As a consequence of all these considerations, the expense for a warhead replacement is out of the current planning horizon. 

The Vanguard-class SSBN are what the current "Trident replacement" is about. It is indeed a submarine replacement program, better known as "Successor Submarine", or Successor SSBN. These four huge vessels have spent at sea all their life, being hard worked to sustain the Continuous At Sea Deterrence Posture. HMS Vanguard, the first in the class, entered service in 1994, and the last SSBN of the type entered service in 2001: in theory, by 2026 their operational life would be over.
Planned to live 25 years, they will now be life-extended by a considerable number of years, with HMS Vanguard having its out of service date moved from 2019 to 2028, and the others following.
Further life-extension is deemed too expensive and risky to make sense. Being only four in the class, these submarines have been worked harder than their American Ohio counterpart, which will start being replaced into the 2030s.

The Successor Submarine is the program at hand. The idea is to build a new class of SSBNs which will operate from the same shore infrastructure (keeping any need for modifications and enhancements to an absolute minimum) and employ, at least for the first part of their life, the very same missiles and warheads now carried by the Vanguards.
The expenditure for new missiles and new warheads, if and when these will be needed and procured, should be kept separate from the submarine part of the deal, as it will be spread over decades into the future.

Successor Submarine – the current plan

At the moment, the plan is to build a fleet of 3 to 4 new SSBN submarines, which will carry the Trident missiles. These vessels will be slightly larger than the current Vanguards, but will use the same shore infrastructure. They will carry 8 launch tubes, in two rows of four, down from 16 on the Vanguards. They will use a new, safer nuclear reactor for power, the PWR3, which is partly responsible from the size growth.
It is intended that the new SSBNs will largely derivate from the Astute-class SSNs: in particular, the two classes will share the same control systems, the same tactical torpedo system and the same sonar suite, making the training of crews similar enough to enable easy transfers from SSN to SSBN and back as necessary.
The new SSBNs will thus have a very potent battery of 6 torpedo tubes and room for 38 torpedoes and Tomahawk missiles in addition to their nuclear arsenal. They will also have a formidable sonar suite, possibly the best in the world, and they will offer the benefit of great commonality with the attack submarine fleet.

The Trident launch tubes module is being jointly developed with the US Navy, to keep costs down as much as possible. This Common Missile Compartment is composed of blocks of 4 launch tubes each, with the new US SSBN planned to have 4 blocks, and the british one 2 blocks. Work on the CMC has been smoothly going on since 23 December 2008, and the maturity of the design is now very high.

It is intended that the overall size of the nuclear deterrent will shrink: until the SDSR 2010, the Vanguards would go to sea for patrol carrying 48 nuclear warheads, distributed unevenly on up to 16 missiles, offering some “flexibility” in the Armageddon scenario, in theory making it possible to retaliate “proportionally” with combinations of between 1 to 48 nukes.
The Successor will only carry eight missiles, and a total of 40 warheads.
As a consequence, the total stock of nuclear warheads will shrink from around 225 to “no more than 180”, of which 120 (down from 160) would be available for operational use at any one time.

The combination of Trident missiles, a fleet of 4 SSBN and a proportionate stock of available warheads ensures that one submarine, loaded with live missiles, is always at sea, 365 days a year, year after year. Once at sea, the submarine is virtually undetectable and offers maximum survivability: so long as CASD is maintained, no enemy is in the position of whipping out with a pre-emptive strike the nuclear arsenal of the UK. Even if they hit and destroy Faslane and the submarines in port, at least one and at times two submarines will be somewhere out at sea, ready to retaliate in little more than 30 minutes: the time Trident takes to hit a target up to 10.000 km away. The ballistic range of Trident means that a submarine hidden in safe waters can relatively easily target anyone in the world to retaliate timely and assuredly.

For me, the Survivability and the Certainty of a nuclear retaliation option are the two decisive factors: a minimum credible deterrent, which is what the UK needs, must absolutely be:

-          Survivable: the enemy must not have the easy option of whipping out the british nuclear deterrent with its own first attack
-          Certain and Timely: the enemy must be in no doubt that a nuclear attack will be met, 100% of the time, with proportionate nuclear retaliation, from which the enemy must have no realistic escape.

If the deterrent cannot meet these two crucial requirements, it is useless. If the enemy can destroy the arsenal at will or defend itself from the retaliation strike, the enemy will not be deterred at all. If it is not Survivable and Credible, then it is better not to devote money to it at all.     

The current and future SSBN solution meets the above requirements.

The current Successor Submarine strategy:

-          Requires a new submarine class to be designed and built, but no new warheads and no new missiles for the time being
-          Makes best use of US collaboration and support, cutting costs while protecting independence of the deterrent
-          Ensures capability to continue mounting a Continuous At Sea Deterrence
-          Does not impact negatively on the availability of attack submarines for conventional Fleet roles


Lengthened Astute with 4 launch tubes: one option that has been mooted is that to build 3 or four more Astutes, inserting an additional module aft of the fin containing a single block of 4 Trident launch tubes.
Unfortunately, this solution is not at all easy and straightforward.

First of all, the current CMC block of four tubes in two rows of 2 sitting side to side won’t fit the beam of an Astute submarine. So the development work done this far would not be sufficient, as we’d have to design a module with the four tubes sitting in a row, one after the other, making the submarine quite a bit longer. 

Workers stand proudly inside the launch tubes of a quad-pack block built as part of the CMC effort

This is, in line of principle, not at all unfeasible: indeed, the US Navy plans to do exactly this on its Virginia class SSNs of the Block V, which have already been fitted with two large vertical tubes in the bow starting with the Block III vessels currently being built. These two large tubes, fitted with “six-shooters” frames holding each 6 Tomahawk cruise missiles, have replaced a more complex and less flexible complex of 12 single VLS tubes mounted on earlier submarines. The US Navy plans to develop, build and install a “Virginia Payload Module” with 4 large tubes into the vessels of the fifth production block. This Payload Module, with 4 tubes aligned to the submarine’s centerline, comes with a pressure hull that is 34 feet in the beam at the fore and aft extremities, going down to a 26-foot wasp-waist around the tubes themselves: this is because space was needed outside of the pressure hull to install the heavy, bulky mechanism of the hatches and additional ballast tanks, plus some unallocated space. An outer, non-pressure hull wraps up and completes the module, maintaining the Virginia’s hull profile and beam (34 feet). The length of the whole module is determined by the need to balance the considerable additional weight made up by the launch tubes and related machinery.   
On the Astute, the arrangement would have to be pretty much the same, since while the Astute has a larger beam (11.3 meters against 10+ for the Virginia) it is still not enough to make another configuration viable.  

A General Dynamics Electric Boats image, showing the Virginia Payload Module with its four large tubes, here fitted with a rack for 7 Tomahawk missiles each. Two further large-diameter tubes, even shorter and carrying only 6 Tomahawk each, are fitted, outside of the pressure hull, in the bow of the Virginia subs from the Block III vessels onwards. The VPM's four tubes offer greater flexibility than the bow ones as they can be accessed from inside the sub. The bow tubes, being outside of the pressure hull, cannot be accessed by the crew.

But, since an option does exist, why is this not a viable alternative Vanguard replacement for the Royal Navy?

For a pretty simple reason, which is the same main problem ruling out a Virginia-based Ohio replacement: the launch tubes fitted to the SSN have the same diameter of those fitted to the SSBN, but don’t have the same length. The difference in sizes between SSN and SSBN are not casual: the Trident missile is a big beast, and is 44 feet long (or tall, if you prefer, since it sits vertically in the tubes).
In an Astute submarine, the launch tube would offer at most 36 feet of useable length, so the Trident missile would suddenly need a whole new replacement that the UK would have to fund on its own.
The Virginia Block 5 will use its 4 large tubes to carry modules with 7 Tomahawk each, increasing the cruise missile load on the SSN up to 40, counting also the 2x 6 in the bow. Even more Tomahawk could be carried in place of torpedoes, and the large-diameter tubes are seen as a mean to future-proof the submarines, enabling them to employ, in the future, new missiles, unmanned vehicles, special forces gear, and other kit.  
The Virginia Block V, in fact, was immediately deemed unsuitable as an Ohio replacement solution: the US Navy envisions the new vessel as a replacement for the 4 Ohio submarines that were modified into SSGNs. The US Navy in fact is aware that a boat as ambitious and expensive as an Ohio is not going to be affordable in the future, and it has been deemed more effective to replace such SSGNs with boats that have obviously far less firepower (a converted Ohio can carry some 66 special forces operators and a load of Tomahawks that can reach the amazing figure of 154 missiles) but that will be more numerous, and will overall add more capability to the fleet for an advantageous pricetag.
The current Ohio SSGNs will be retired from service starting in 2026, so the US Navy is obviously already at work over the Virginia Payload Module, with the aim of starting the building of the first Virginia Block 5 in 2019.

It is probably not technically impossible to fit Trident missiles into an Astute, but this would have a dramatic impact on design and performances of the submarine, as it would be necessary to gain a good 8 feet in height over the back of the submarine, and this would impact weight, hydrodynamics, stealth when surfaced and, crucially, it would have a very bad effect on acoustic, making the submarine a lot more noisy when underwater, and thus much easier to detect, a problem typical of certain Russian SSBNs, such as the Delta IV, which very evidently show such a hump behind their conning tower. 

Something like this would be the result of trying to fit Trident II missiles into an Astute hull. This solution would be relatively easy and cheap, but would ruin the submarine's performances, making it slower and louder underwater. 

The Americans, unsurprisingly, absolutely did not want to walk this path with their replacement SSBN and with the Virginia Block V.
While technically feasible, it is a very bad solution for a lot of reasons. The savings would be negligible, and the submarine coming out of this solution would be, basically, a flawed design, using a solution that everyone has abandoned because of its defects.
If we went with the shorter tubes and tried to design a new ballistic missile to fit into said tube the costs would skyrocket, and the UK might well not have the industrial capability to develop such a complex ballistic weapon on its own, since there is no real previous experience to build upon.

Arguably, the Astute SSNs should have been built with large vertical tubes, but like with the Virginia Block V, these should not stretch out of the carefully designed hull profile, and thus would be not be Trident tubes. 

The Virginia Block 3 bow in direct comparison with the bow arrangement on submarines of the earlier batches. Best thing is, these changes not only improved the sub, but cut costs of construction by a good few million dollars.

An Astute-with-tubes would be an excellent SSGN and potentially a good vector for a cruise missile-based deterrent, at most. 
But the problems connected to a nuclear-tipped cruise missile are numerous and significant:

-        The nuclear-tipped Tomahawk is gone, so there is no easy option.
-        Politically, a new, british development of Tomahawk fitted with a nuclear warhead would be inconceivable. The Tomahawk is one of the most precious, effective and frequently used weapons in the US and UK arsenals, and the political and operational cost of having every single Tomahawk launch possibly mistaken for a nuclear attack is absolutely unacceptable.
-          Developing from scratch a new missile, even one relatively conventional in design, would be expensive, and would also require a new nuclear warhead to be designed. The cost could balloon up immensely if, to counter the greater vulnerability of a cruise missile compared to a ballistic one, the decision was taken to build a stealth and/or hypersonic missile.
-          The cruise missile would never be able to match the useful range of the Trident missile, or its survivability. Shooting down a cruise missile is far easier than trying to kill small warhead re-entering the atmosphere at Mach 25. The range limit means that the current hiding places used by nuclear-armed submarines in the Atlantic and Arctic oceans would be useless: from there, the submarine would be unable to hit anything. What will the submarine do to retaliate against an attack coming from far away, from an unexpected direction, via ballistic missiles? The submarine will run towards a suitable launch area within range of the target, to launch a retaliation days after the attack, risking to be sunk by an enemy which will be aware of the cruise missile threat?   

For a cruise missile to be an effective deterrent capable to hit high-technology enemies (the only ones capable to start an attack requiring nuclear response, arguably), the ability to get past layered air defence systems is indispensable. It should also have thousands of miles of range to enable the submarine to stay a safe distance away from the enemy while it launches the missiles.
And there are only so many routes a low-flying cruise missile can use, making it relatively simply for the enemy to prepare its air defence batteries and, even worse, maritime patrol aircrafts and warships patrolling the possible launch areas.

I think the cruise missile option does not meet the requisites to be considered a Credible deterrent.

Anyway, the Astute-with-tubes solution offers:

-          Negligible savings, assuming that an “hump” solution is adopted to retain Trident missiles. The new submarines will probably cost significantly less, but the design challenge is still significant, and new subs would still be required. Worse still, the new vessels would have their performance depleted or compromised in terms of speed and stealthness. The number of missiles and warheads could shrink further, contributing to the savings, but the reduced number of missiles also reduces the flexibility and lethality of the deterrent. If the firepower shrinks too much and during the life of the deterrent anti-ballistic technology progresses further, an enemy might become realistically certain of its ability to shoot down all the re-entry warheads, nullifying the effect of the deterrent.
-          If the shorter tubes are adopted, and the decision is taken to drop Trident and develop a new ballistic missile, costs rise dramatically. It probably would end up costing more than going onwards with the current plan.
-          If the cruise missile solution is adopted, a new cruise-missile and a new warhead will need to be developed and produced, eroding the possibility of achieving any real saving. All the limits of the cruise missile option will have to be accepted if this road is chosen. 

Flexibility: you can fit a multiple Tomahawk launcher assembly into a Trident tube and still have a lot of space to spare in the bottom half of the tube. Room for future developments and for new uses.

Nuclear-tipped cruise missiles fired from existing, modified Astute subs: the key word here is “modified”. How much modifications will be required to enable the safe carriage of nuclear-tipped cruise missiles in the torpedo magazine? How would said modifications impact the submarine’s performance in its other roles?

This option offers the promise of great savings, even if a new missile and warhead would need to be developed, and the Astute submarines would need modifications for their safe stowage and use. I don’t think, in fact, that it would be accepted to just embark nuclear weapons without proper procedures and equipment being developed.

This option would very likely negatively impact the attack submarine fleet. It would become politically harder to send the Astutes around on their conventional missions, and it wouldn’t be surprising to see nations denying their ports to the visit of an Astute. It could be a real problem in the Persian Gulf.
It is pretty much certain that only one Astute at a time would carry nuclear-tipped missiles, and this one submarine would be hiding like an SSBN, deep into the ocean. It would mean, effectively, dramatically reducing the availability of Astute submarines for their normal missions, and this would have a terribly negative effect on a fleet that is already too small to meet its many commitments. Building at least a couple more Astutes would be absolutely indispensable, but this would further reduce the savings, and there would still be plenty of limits and issues.

Basing the nuclear missiles on surface ships, such as Type 45s, would be even worse, both politically and operationally. And it would also further erode the survivability of the deterrent.

Cruise missiles in a cupboard: this is the most demented proposal after the unrealistic plan for land-based missile silos.
Hiding an entire nuclear arsenal in a bunker in the british countryside will present countless challenges, and I absolutely cannot agree with a course of action of this kind, which would put future british governments in the difficult position of having to order the Navy to open the bunker, load a submarine with missiles and set sail “in times of heightened tension”.

Taking the decision to bring the nukes out of stowage would an hugely impressive move, but it might very easily impress in the wrong way. It could cause a sudden worsening of the situation, instead of bringing back the calm.
There is a big difference between routine patrols going on at sea from well over 40 years and the sudden show of nuclear might connected with the decision to blow the dust off the nukes.
The submarine routinely out at sea is aiming its missiles at everyone, yet at no one at the same time. It is there, somewhere, lurking in the deep, away from the eyes, but always present. It causes prudence, and it cannot be contested.
But the images, shown on television, of long stored nuclear missiles being brought out of the bunker and loaded on the submarine would send a sudden, harsh message which is unlikely to be of real help, because it changes from a routine to an exceptional event, a signal of sudden, dramatic escalation.
Any government would find it hard to take such an important decision.

Worse, this kind of deterrent is not responsive and is not survivable. If, for any reason, the nukes were still in stowage when the first ballistic missile was launched, there wouldn’t be enough time to do anything. The warheads could be raining from the sky in as little as half an hour, and the first nuclear strikes would inexorably target the arsenal.

For me, this option absolutely isn’t credible.

Indeed, in my opinion there is no realistic alternative to a new class of SSBNs. While there are technically different approaches that could be selected, they all ensure a series of problems or degradations in capability, while delivering only rather vague promises of savings.