Old ships - educate me please
 

One for the Navy types. I read about HMS XYZ being "old and knackered", and that means they have to be laid up and ultimately scrapped.

What is it that fails so spectacularly as to cause the vessel to be retired?

Take Invincible, for instance. Been laid up for 5 years or so, and headed for the scrapper shortly. Engines no good? Aren't they Olympus? Is it that big of a deal to replace them? While not trivial, similar engines on aircraft are changed on a daily basis around the world.

Shafts? Bearings? These are basic mechanical devices.

Maybe things like seals and pipes. Corrosion? Why not make them out of corrosion resistant alloys to begin with? Change the seals?

Electronic systems? Again, piece by piece not that difficult to repair/replace. The whole system might be a big deal, but could it be done for MUCH less than the cost of a new ship?

Things like Airconditioning, fresh water plants, motors, cranes, etc are again basic (ish) mechanical devices.

Crew accommodation, galleys, messes, these are again not big ticket items.

I find it hard to believe that a ship with a sound hull is beyond redemption. Looking at museum ships (HMAS Vampire, HMS Plymouth, USS Intrepid, Iowa battleships, USS Texas, HMS Belfast), they're not in bad mechanical condition. Maybe obsolete, and I'm sure the engines and such are rusted up through disuse, but the fabric of the ships aren't in danger of falling apart.

Is it just straight bean-counting, or is there something I am missing?

I'm afraid it's more than that.

First and foremost, there are no fundamental reasons why ships cannot be extended forever and a day. Unfortunately, doing so incurs costs that are either comparable with or more than the cost of a new build ship. A few reasons why -

1. Weight growth. All ships incur weight growth through-life and quite often vertical centre of gravity increase as well. This affects both stability (weight and VCG) and structural strength (weight only). While some elements of growth can be accounted for fairly easily (oh look, that wasn't there when she was built), others cannot and include things like redundant cabling left in the ship, paint, minor seatings etc. These can add up to several hundred tonnes on even a frigate sized ship (there are type T23s running round with well over 10% increase in weight already!). Stability certificates are being brought more in line with IMO legislation and in terms of safety cases are being made ALARP which essentially means that over time standards will gradually become more onerous.

The only way to recover stability is either to add ballast (and we're talking in hundreds of tonnes of lead here) or remove all the weight (which essentially means gutting the ship, blasting back to bare metal and then reinstalling only what the latest mod state says should be there. This involves lots of manpower, which is very expensive and limited in application (ie you can only get so many folk on a ship at the one time), so the job takes longer.

Adding lots of ballast just adds to your structural strength problem and because the ship sits lower in the oggin makes your damaged stability worse - you are in effect, chasing your tail.

Structural strength itself requires adding lots of additional metal to the upper decks and the keel to bear the increased load (weight, buoyancy and wave loading), which again is expensive, adds weight and doesn't help stability. Tail chase again.....

2. Corrosion of ships hull. Again, can be overcome by replating, but becomes progressively harder to do as you chase sound structure, reducing availability and costing more than new fabrication. All the museum ships you quote require regular dockings (see Intrepid recently and Alabama a few years ago with extensive replating) and none of these are certificated to go to sea. they can get away with dockings every ten years or more, but are not expected to be subjected to wave loading, hence lower standard required.

3. System obsolescence - another big killer. Again, huge amount of cost involved. You can't actually extend gas turbines indefinitely either, nor missile motors, or electrical cabling etc. You have to rip it all out and fit new - which may be a different standard to that which was built, bringing different problems in safety world.

After all that, you've got a phenominally expensive platform, which still has simlar performance to when it was built, which may be much less than required now. Better all round to spend on new and overcome the nasties identified above at design rather than try and bodge them.

Roadster,
I’m no expert (I have worked ships through refit) but I was on the Invince for her last commission and I have spent my whole working life in the RN.
The Invince (for example) was rotting structurally and her systems were far from functional. I can remember the joys of the Norwegian trip with no accommodation heating (lovely!). The whole of the last commission was carried out with a refrigeration container in the aft hangar because the ships unit was knackered beyond repair. The Ark (which was standby at the time) was robbed blind to keep the Invince running, although as you say, the engines are easy to change, I know the stokers were getting stuff from the Ark flown out to repair the engine ducting. Anyone who ever served on the Invince will be able to tell you tales of her dodgey shaft, which reared it’s expensive head every now and then.
The use of “exotic” materials in the construction of ships would be a non starter, the specialist skills required to work some of these materials is not easy to find on an industrial scale. Add to this the cost of these non-corrosive materials, you could end up increasing the build costs beyond what would be economic (they would say, “why build to last 50-60 years when 25-30 will do?”).
Don’t forget that any bits required for these ships now are going to be bespoke construction, I would imagine the support contracts are long gone and any “one off” lump of metal or component costs big time. (That tends to be the case with any ship class that’s nearing it’s sell by date.)
It’s relatively easy to keep a museum ship afloat, you just keep pouring quick setting cement into the bilge (Ah memories!) but if that ship has to move and fight you are in a whole new ball game.
I suppose in the end it’s a simple calculation based on cost to build/buy for 25-30 years use, against refit for one more commission and hope nothing big breaks. (I don’t even know whether seaworthy certification comes into that calculation)

Cheers

So you refit them by giving them a lick of paint and sell them in an unsafe condition to some unsuspecting second-user navy? Hardly ethical is it?

But they are not unsafe you argue, in which case you have some way to go before catching your tail?

Looking at OldGrubbers post too, it is patently obvious that someone had to be telling porkies over a 50-year life. Also the suggestion that they would be sold on after 30 years as part of the plan does not sit with the MP for Kirkcaldy seeking assurance that the maintenance contract for the next 60 years would go to Rosyth.

You have to remember that COTS rarely applies to any RN ship.

A mildly odd example was HMY Britannia. She was fueled by heavy bunker fuel, not diesel, so could not be deployed in wartime without her own dedicated tanker, and her AC supply was generated by diesel engines that had been standard fit for wartime submarines.

Just re-plumbing a warship for an up-to-date C3I fit is a nightmare.

Not unethcal whatsoever.

The ship no longer meets the standards required by the RN (in this instance). That's not to say that an up and coming, poorer navy won't find that the ship is ideal, with regard to cost/modernity/function, for their purposes.

'Sold as Seen'!

Thanks for the replies, it does explain a few things.

It seems to me that if the life is 25-30 years, then that's great, so long as there's a coherent plan for replacement kicking in at 25 years, and fully on stream by 30. Invincible was built in 1978, 32 years ago. Illustrious 82, Ark Royal 83. If Illustrious makes it to 2020, it will be nearly 40 years old.

By the sounds of things, she won't, and so there'll be a big old gap with no carriers AT ALL. Mind you, perhaps not so important with no Harriers anyway.

R.... HMS Victorious 1937-1969, and was getting ready for another Commission, but for a fire and the Labour goverment.:{ Swordfish through to Buccaneers:D

What has struck me recently is that military aircraft now seem to be remaining in service longer than warships. For instance the RAF Puma fleet is now expected to remain in service until around 2025, which will make the airframes more than 50 years old at retirement, but naval contemporaries of the Pumas, such as the Leander class, are long gone.

Not_a_boffin mentioned weight growth.

The Vulcan put on over 5 tons during its life with the first major weight increasing being over 8000 sq ft of polyurethane paint.

I don't know about weight growth on others but I do know there was a problem between the Mk 1 and Mk 2 Nimrods which meant the latter had to manoeuvre on the ground at low speeds. On the Mk 3 it required the deck to be reskinned and carpetted to save weight and for the Mk 4 to be re-winged and have a stringer undercarriage.

You can argue that warships are bigger than aircraft but then you have more space within which to work and more people can work at the same time.

XR

Exactly. Most of the USAF's B-52s are older than the Navy's oldest carrier (Enterprise) and will fly beyond 2020. There are first-line F-16s that were delivered in the late 70s/early 80s and will carry on beyond 2015, having outlasted most contemporary cruisers and destroyers.

A ship logs lots of hours - it has to, as it's not much use unless it's close to the scene of wherever action might break out - in a corrosive environment. However, the big deal is that it is not adapted as easily as an aircraft, which can take on a new mission by adding a new whizzbang or pod and has electronic bits that can be easily changed by unscrewing a new panel.

Related question (Mr Boffin): What happens when you replace almost all the aircraft on a carrier with aircraft that weigh twice as much? Ship stability is a bit of a mystery to me.

If you really want to save weight on a MPA, remove the galley!

Wot, no pies?

That's easy - you keep 50% of them airborne.

NR,

So the burning question was whether the MR2 and MRA4 sims were complete with Galley or not.... We should be told!

S41

"Exactly. Most of the USAF's B-52s are older than the Navy's oldest carrier (Enterprise) and will fly beyond 2020. There are first-line F-16s that were delivered in the late 70s/early 80s and will carry on beyond 2015, having outlasted most contemporary cruisers and destroyers. "

Please forgive a stupid question, but of those F16s, how much of the original F16 is left, and how much has been replaced, updated, changed or refitted over the years? Is it a case of triggers broom (6 heads, 4 shafts) or is this genuinely a 1960s vintage airframe?

I've seen some suggestions that the current HMS Victory is only about 15% original build now, and the rest of her is much more modern. Shes essentially an imitation of the ship that was at trafalgar.

PN

Looking at OldGrubbers post too, it is patently obvious that someone had to be telling porkies over a 50-year life.

Not so. If you design and plan for a 50 year life (margins etc) then it will be able to do so. CVF has a stonking growth margin in for stability - strength usually less of a problem in a deep multi-deck ship, plus system margins as well. The problem is where you don't do that and try to run ships beyond their design lives (eg CVS 25-20 yr design life as a helicopter carrier, not an aircraft carrier).

XR219 - Leanders died because they were manpower intensive (250 crew) and developed stability problems as they got old. Puma airframes (and BUFFS for that matter) can be stripped down and blasted to bare in depth maintenance relatively easily (you don't have a couple of hundred compartments in an airframe - except maybe XH558!)

LO - The days of massive aircraft weight (and size) increases are hopefully long gone - topped out in ~1972 with the F14. In terms of impact - it depends on the size of ship relative to CAG. Lightship of a CVN is ~ 60000 te and assuming a 85-ship CAG with an average weight of 25 te, the aircraft payload works out at 3.5% - can't see the frames getting much heavier. On a CVS, the equivalent is closer to 2%. Not really going to make a huge difference.

I reckon the breaking strain was less than 2lbs and the spotted fly worked wonders. Clearly the fish in Portsmouth Harbour take the fly easily. :}

JL - There have been a number of life-extension programs, but not a new airframe in a real sense, and not a case of new wings or anything like that. Not extensive as the center barrel replacement on the Hornet, as far as I know.

Mostly, extending service life to 8000 h involves replacing some highly loaded parts and modifying others.

Replacing tons of 1200psi D-type boilers and HP/LP turbines and their associated equipment (circ pumps, ejectors, steam turbine generators, forced draft blowers) with gas turbines is an attractive notion, but the cost of the refit doesn't fly. Too many ship systems suddenly need alternative motive force, and even basic hotel heat would still need to be re-thought.

Never mind the changes to the ship's CG and displacement.

The cabling changes required to upgrade early-70's sonar, radar and self-defense systems alone would be outrageous.

Newer platforms are also built to a completely different compartmentalization and environmental strategy to provide positive pressure boundaries in the face of chem/bio attacks, and the structures are better hardened against EMP.

The sound signatures and masking of newer-designed hulls far outshine the standards that we maintained in the early 90s.

Et cetera, et cetera, et cetera.

The Turks and the Greeks were thrilled to have our older ships, and I was just as happy to hand them the keys rather than see them cut up for scrap.

All ships incur weight growth through-life and quite often vertical centre of gravity increase as well. -Not a Boffin

You can say that again! One carrier I served in floated one full deck deeper in the water compared with when she was built, and there were very strict rules in force regarding the opening of scuttles which had formerly been well clear of the waterline .....:uhoh:

Jack

I thought you might like to see how they disposed of my first ship (Berwick)

Type 12 Sinkings


Cheers all

USS Enterprise CVN-65 vs B-52H.

CVN-65 laid down 4 February 1958; launched 24 September 1960; commissioned 25 November 1961.

B-52H first flight 20 July 1960; first delivery of operational aircraft to USAF 9 May 1961; last delivery (102nd "H" model) 26 October 1962.

As the only B-52s in the USAF inventory are "H" models (all earlier ones being scrapped or sitting in desert storage for decades), I'd call it a draw.

Ah, but CVN-65 OSD = 2013 (according to Wikipedia), B-52H OSD = 2040+ :eek:

GK - As XR points out, that is the oldest CV in the fleet and not long for this world.

HMS Victory 1765 - TBD. :p

INVINCIBLE no longer - Don't all rush at once ......:sad:

Disposal Services Authority

Jack

Interesting to read the spec which served to confirm the info on wiki:-

"On 6 June 2005 the Ministry of Defence announced that HMS Invincible would be inactive until 2010, available for reactivation at 18 months' notice. She was decommissioned on 3 August 2005, just 14 months after an extensive modernization/refit (even the propulsion gearboxes were replaced) which had been intended to give her ten more years of service. According to Jane's, however, because she was stripped of some parts for her sisters it would require not only 18 months but also the removal of systems from the other ships to bring her to a state of operational readiness. Invincible was struck off the Naval Reserve List on September 10th, 2010"

BTW the SDR stated that the UK would maintain an Ice Patrol Ship to guard our South Atlantic interests. Until a new one is built (unlikely) or leased (possible but not yet confirmed) HMS Endurance is that ship and she is unlikely to leave Port under her own power again either.:*

I believe that an announcement is due fairly soon on the new Ice Patrol ship, but while Endurance is broken, Scott is filling the role. I think the UK will find the money to put a new endurance into service.

To be fair on the MOD, the plan was always to pay off Vince in 2010, and its always been clear that this would happen. The real surprise is the loss of Royal 3 years earlier than planned.

I hope you are right but my concern, given the current spending environment, is that as HMS Scott has been able to replace Endurance for two Seasons (and without any Lynx helicopters) it might become the Patrol Ship:rolleyes:

55 We need a Wasp on board in strike role!! with 4 AS I2s underslung;)

David

Or a Lynx with Sea Skua:cool:


If I could figure out how to post an image to PPRuNe I would be able to illustrate:confused:

http://farm3.static.flickr.com/2169/...1d9b5d7aed.jpg

This what you had in mind? :ok: Yes, it's a German cab :=

draken55 see http://www.pprune.org/spectators-bal...une-guide.html

Thanks for your help chaps:O

Here's what I had in mind.http://i1084.photobucket.com/albums/...Britain008.jpg

Joint Exercises Trincomalee 1957 (JET '57)

In 1957 I was stationed at RAF China Bay, across the bay from the RN Base at Trincomalee (HMS Highflyer).

Each year the RN, Pakistan & Indian Navy held joint exercises in the Indian Ocean off Trinco together with aircraft from the RAF and Indian Navy. RAF participants in JET '57 were four Sunderlands from 205/209 Sqn detached to China Bay from Seletar. Short Sealands of the Indian Navy and Bristol Freighters of the Pakistani Air Force also participated in the exercise.

Two 205/209 Sqn RAF Sunderlands were dispatched to find and 'attack' the enemy during Joint Exercise Trincomalee '57. I was aboard one which was in formation with Sunderland 'N' RN282 as seen below.

http://i145.photobucket.com/albums/r...nFormation.jpg


http://i145.photobucket.com/albums/r...ngTwoShips.jpg

We found and 'attacked' a couple of warships in the Indian Ocean seen here at anchor off the North-East coast of Ceylon (Sri Lanka). This view is from the Sunderland's front gun turret as we 'attacked'. In the foreground is Pakistan Navy ship 'Jhelum' (F-40) formerly 'Narbada' - a Bay or Loch Class Frigate of the Indian Navy allocated to Pakistan on Partition in 1947.

The warship in the background is Pakistan Navy ship "Khaibar" formerly RN Battle Class Destroyer HMS Cadiz. HMS Cadiz (D79) was transferred to the Pakistan Navy in 1956/7 as PNS Khaibar. Smoke can be seen coming from 'Khaibar's' anti-aircraft guns amidships as she fires blanks at us whilst 'Jhelum's' turrets are trained directly on the aircraft.

May I just point out that fish 'eads just love 'em being called boats, despite all the frothing at the mouth protestations to the contrary.

If you can row it,it's a boat if you can't it's a ship.
but a WAFU can do anything,with anything to anything,simple innit?:E

Nah, they's all boats. You love it really.

Warmtoast

Are you sure it was a D? This link HMS Virago, destroyer says she was an R.

Then to further muddy the water, comes this one HMS Virago

Then even more confusion U+V Class Destroyers