3 New Navy Vessels for Irish Naval Service

I’m well familiar with what the Flowers were and how they operated in the 1940s, suggesting that they were still capable of being a threat to submarines in the early 1970s is a bit of a stretch even if their systems had been fully operational. They weren’t by the end of their life’s in any shape or for something like a modern maintained Perry.

To be fair those were the USN Perrys, the Aussie ones went through a fairly expensive (perhaps too expensive) upgrade, though even then they were built in and for an age of nuclear subs and far more advanced conventional ones compared to what the Flowers would have been asked to deal with (if we had maintained ASW operations) by 1970.

I have to wonder if the government in the 1920s had come to some agreement with London between the overly ambitious “plan” from Dublin and the cautious plan from London what Navy we might have developed even if we had stayed neutral in WW2?

They are likely to be fully engaged with the new U.K. contract for the next 10 years at least, fitting in an MRV isn’t happening unless we pushed the replacement into the mid 2030s.

Can you build in the open without a covered structure?

As we seen form the DUP last week it appers they like certain aspects of the EU if money is involved!

UK carriers were both assembled in the open, modules assembled under cover.

To be fair it's not like anyone didn't think that anyway, same as their trip to Dublin last time. Now we just have to wait to see when the MRV order crawls over the line.

Wonder if it would be the Crossover design they would put forward?

https://www.damen.com/vessels/defence-and-security/crossovers

Well the Air Corps crew that landed on the ship looked fairly happy with themselfs.

If you are joining the air corps surley this is what you want to be at along with Army operations and others such as HEMS and SAR otherwise you would have joined the private sector

Its fair to say this Forum was well ahead of this conversation!

If you were to play “fantasy fleet” time, the different variants of the Crossover could handle both the MRV and the not too distant P50 replacement?

An update on P72

https://twitter.com/naval_service/status/1598026387449085952

Are they being retro fitted with 30mm cannons?

Housings for depth sounders I would guess.

Vital on an inshore boat.

Sacrificial anodes. Because the alloys used on props and hulls like to react with salt water, zinc anodes are bolted around the hull of all steel or aluminium hulled vessels, to soak up corrosion.

It used to be 1st year secondary school science.

They are made from a metal alloy with a more "active" voltage (more negative reduction potential / more positive electrode potential) than the metal of the structure. The difference in potential between the two metals means that the galvanic anode corrodes, in effect being "sacrificed" in order to protect the structure.

In brief, corrosion is a chemical reaction occurring by an electrochemical mechanism (a redox reaction). During corrosion of iron or steel there are two reactions, oxidation (equation 1), where electrons leave the metal (and the metal dissolves, i.e. actual loss of metal results) and reduction, where the electrons are used to convert oxygen and water to hydroxide ions (equation 2):

Fe -> Fe^2+(aq) + 2e-

O2 + 2 H2O + 4e- -> 4 OH- (aq)

In most environments, the hydroxide ions and ferrous ions combine to form ferrous hydroxide, which eventually becomes the familiar brown rust:[3]

Fe^2+(aq) + 2OH- (aq) -> Fe(OH)2(s)

As corrosion takes place, oxidation and reduction reactions occur and electrochemical cells are formed on the surface of the metal so that some areas will become anodic (oxidation) and some cathodic (reduction). Electrons flow from the anodic areas into the electrolyte as the metal corrodes. Conversely, as electrons flow from the electrolyte to the cathodic areas, the rate of corrosion is reduced.(The flow of electrons is in the opposite direction of the flow of electric current.)

As the metal continues to corrode, the local potentials on the surface of the metal will change and the anodic and cathodic areas will change and move. As a result, in ferrous metals, a general covering of rust is formed over the whole surface, which will eventually consume all the metal. This is rather a simplified view of the corrosion process, because it can occur in several different forms.

CP works by introducing another metal (the galvanic anode) with a much more anodic surface, so that all the current will flow from the introduced anode and the metal to be protected becomes cathodic in comparison to the anode. This effectively stops the oxidation reactions on the metal surface by transferring them to the galvanic anode, which will be sacrificed in favour of the structure under protection. More simply put, this takes advantage of the relatively low stability of magnesium, aluminum or zinc metals; they dissolve instead of iron because their bonding is weaker compared to iron, which is bonded strongly via its partially filled d-orbitals.

For this protection to work there must be an electron pathway between the anode and the metal to be protected (e.g., a wire or direct contact) and an ion pathway between both the oxidizing agent (e.g., oxygen and water or moist soil) and the anode, and the oxidizing agent and the metal to be protected, thus forming a closed circuit; therefore simply bolting a piece of active metal such as zinc to a less active metal, such as mild steel, in air (a poor ionic conductor) will not furnish any protection.

Not sure what caused the LCS problems, but I know a small crew contributing to lack of maintenance was one of them.

Oh the LCS program has had so many problems it's hard to keep count of them (only the US could piss away so much money on a fleet of Lemons), but it was one of their earliest ones:

https://www.wired.com/2011/06/shipbuilder-blames-navy-as-brand-new-warship-disintegrates/