The numbers of repair vessels in navies has dropped off significantly over the last few decades. This can be partly explained by stretched naval budgets and the decline of large-scale naval engagements in modern warfare. But the decrease in demand for repair vessels can also be attributed to at-sea maintenance and repair vessels having what navies refer to as a “Cinderella” role both during times of war and peace. In other words, these ships can be intensely useful for reacting to emergencies, possibly making the difference between life and death, but can be seen as a poor investment outside of these crisis moments.

As modern conflicts increasingly require fleets to be active in far-off waters for extended periods of time, repair vessels should still be valued for their ability to maintain and repair ships without having to relocate to a friendly port.

From a civilian perspective, repair vessels can also provide rapid aid in humanitarian disasters by providing power and workshops to the shoreline. While the unpredictability of these disasters means repair vessels can be a costly investment, this same unpredictability is what makes them useful as a rapid response option.

Andy Kimber is a senior manager within UK company BMT Defence Services’ naval architecture department, and has provided consultancy services to the UK Ministry of Defence on repair vessels, as well as developing proprietary repair ship designs and concepts. We caught up with Kimber to talk about the changing role of repair vessels and how their functions might evolve in the future.

“In a repair ship, you will have the ability to provide power, firefighting systems and water over the side to the ship you’re repairing.”

Chris Lo: Could you give some background on the role of repair vessels within navies?

Andy Kimber: Yes, well certainly in the case of the UK, you’ve got a ship that is procured against the role of battle damage repair. But obviously, once you’ve got a ship like that, it has an awful lot of use in peacetime for maintenance; Diligence [RFA Diligence, Royal Navy fleet repair ship] has obviously been spending a lot of time out in the Gulf acting as a maintenance vessel out there to the ships deployed on the Armilla patrol. And of course it can do other things, in terms of humanitarian relief.

CL: Are there any recent conflicts where repair vessels have particularly proved their usefulness?

AK: Yes. From a UK perspective, obviously the Falklands was the last noticeable case, when Diligence was converted from commercial usage for the Falklands and sent there as a repair ship. So that’s certainly one case. As I mentioned, during the Gulf, Diligence was out there for a very long time, acting as a maintenance home for the ships that were on patrol out there.

CL: What are the civilian applications of repair vessels?

AK: There was a case, around about 2008 or 2009 where Diligence provided assistance after a big hurricane out in the West Indies. She actually provided assistance ashore; she came into the port, because the thing about a repair ship is, to conduct repairs it has to provide services to the ship it’s repairing. If you’ve got a ship that has been damaged, it could potentially lose power, it could lose its saltwater system which means the loss of firefighting capability.

So in a repair ship, you will actually have the ability to provide power, firefighting systems and water over the side to the ship you’re repairing. That also means you can go into a port and do the same thing, so you can provide power ashore, you can provide water ashore, and you can provide manpower and tools and facilities. So she has certainly done that in a humanitarian role, where she has berthed up and provided manpower and assistance ashore.

CL: Are there any particular challenges when it comes to new repair vessels, or are most converted from existing ships for repair tasks?

AK: A lot of them, historically, are converted. Diligence, obviously, was converted. A few of the other ones operational today tend to be ex-warships or ex-auxiliaries that have been converted for the role. Generally you need lots of space, lots of power and lots of accommodation. It’s a volume issue more than anything; you need a fairly big, quite manoeuvrable ship with lots of services.

CL: What technology and techniques are employed to provide repair services at sea?

AK: In terms of repair, it’s essentially to recover a ship that may have lost power or may have a fire and therefore needs assistance. So the task is to patch it up sufficiently so the ship can get back to a port. So you see a lot of heavy steelwork – you’re looking at metalwork shops and woodwork shops just to craft plate to weld in place to patch holes. Also, providing power.

We’re talking fairly heavy engineering. Cranes are also a core component. Particularly for battle damage, you’re probably taking plate across to patch holes. But in terms of maintenance, you might want to take pumps or generators across on to the repair ship to repair.

“It doesn’t take much to expand the medical facility of a submarine rescue ship to make it a fairly good medical vessel in its own right.”

CL: What role does BMT Defence play in this field?

AK: We did a study for the MoD in April 2008. That was a piece of consultancy, looking at future options for repair ships. Other than that, we’re also looking to develop ship designs and concepts. We’re working on a concept that we’re terming the “specialist utility auxiliary”.

What we’re doing is looking at a variety of these very specialist roles of auxiliary ships – you’ve got repair ships and maintenance, submarine rescue, towing, hospital and medical, all these Cinderella roles, and one thing that struck us is in all the studies we’ve done across these types of ships, they tend to come out quite similar.

So with the specialist utility auxiliary, we’re looking at a family of designs, where either we could take the generic design and produce a customised version for one particular role, or we could look at something that’s more modular and could perform several of those roles by using containers and modularisation. Or even possibly mix and match.

For example, we’ve got a design for a submarine rescue ship. The thing about a submarine rescue ship is it actually has to have fairly good medical facilities because you’re dealing with divers, and you need hyperbaric chambers and facilities in case you have injured personnel. It doesn’t take much to expand that medical facility to be a fairly good medical vessel in its own right. So we’re looking in this area at a family of designs covering these roles, from one base design.

CL: Numbers of repair ships have dropped off since the days of large-scale naval engagements. Is budget the reason for smaller numbers, or is it also because of the availability of friendly ports around the world?

AK: I actually think the latter reason goes against it, to be honest. I think the experiences out in the Gulf proved that it’s quite good to have a maintenance ship. But I think the reality is that these are Cinderella roles. They’re not very high-profile; they’re very important but they’ll be very important for very small amounts of time.

So I think what we’ll probably see is fewer ships and more modularisation. One way is to go extremely modular and not have the ship at all, just have the facility that you can host on a ship you take up. There’s a thing the Royal Navy calls the Forward Support Unit, which they use to support MCMs (mine countermeasures vessels); they actually have a fleet of containers and they can basically host those on any ship that has suitable space for them.

CL: What new developments could be introduced for newer generations of repair vessels, in terms of new capabilities?

AK: I’m not sure they will fundamentally change, because it’s all about having space for the repair crews, cranes to lift things around, and it’s about having workshops. In terms of maintenance, things will change, simply because modern equipment requires less maintenance and it also tends to be repaired by exchange.

So I think the traditional role of a repair or depot ship with loads of stores and workshops will disappear a little bit, because where you need maintenance, it will be specialist maintenance and it will probably be a lot of repair by exchange. I suspect the future is less having dedicated ships for each of these roles and more moving towards either a ship that is multi-role or ships that are reconfigurable.

“I think what we’ll probably see is fewer ships and more modularisation.”

CL: You have previously described the concept of the float-on float-off repair vessel. Could you explain this concept?

AK: What I was looking at was this concept that the repair ship just hosts a facility. The ship itself is almost unnecessary. Obviously, having a ship requires maintenance for the ship; it requires crew, it incurs cost.

So what I was looking at was essentially using a barge to have the repair facilities, and that can basically be held in extended readiness somewhere.

All you then need is a heavy lift ship to basically move that facility to the theatre where you want to use it. So what I was looking at was getting away from the costs associated with maintaining a ship for that role, and move towards just keeping the facilities.

One of the problems with the repair ship is that you can do quite a lot of it using containers, but the real problem comes when you want things like cranes and accommodation, because when we’ve done studies it’s very hard to find a host vessel that has a lot of accommodation, a lot of craneage and a lot of space for containers. Very few commercial ships actually fit that profile. So with this float-on float-off concept, what we’re trying to do is to create the total facility with all the heavy lifting gear and accommodation, but not actually have the ship with it.