September 17, 2021

Open Thread 87

It is time once again for our regular open thread. Talk about whatever you want even if it isn't naval/military related.

The big naval news in the last few days is that Australia has torn up the agreement with France to build 12 new conventional submarines, and is instead pursuing SSNs, with aid being provided by the US and Britain. On the whole, this is a good thing, as SSNs are vastly more capable than conventionally-powered submarines, particularly in operations far from base, which is a major concern for the RAN. It's only the second time the US has allowed this kind of tech transfer, with the first being our deal with the British, started in the late 50s and still ongoing today. (Russia and France developed the technology independently, and have exported it to India and Brazil respectively.)

The only fly in the ointment is that the subs are to be built in Australia, because the government there has apparently not learned that treating defense primarily as a jobs program is a great way to run up the budget and delay the schedule. I initially expected them to get Astutes from the UK production line, but that would make too much sense. The announced detail doesn't say where the UK comes into the submarine program, but I wouldn't be surprised if they ended up with an Astute-based sub given how much strain the US nuclear shipbuilding industry is under.

Biden felt the need to clarify that while the submarines will use nuclear power, they won't be nuclear-armed, and I can see why he felt that way and despair about what it says for humanity. It appears that the highly-enriched uranium required for the reactor will come from the US, with appropriate safeguards to keep the Australians from misappropriating it for bombs.

2018 overhauls are the reviews of Salem and Nautilus, SYWTBAMN - Strategy Part 3, Falklands Part 6, the Nimrod Saga and Auxiliaries Part 3. 2019 overhauls are Riverine Warfare in Africa and South America, the 2019 Tinker Airshow, Falklands Part 18, Fire Control Transmission and Naval Ranks - Officers. 2020 overhauls are Operation K, Information, Communication and Naval Warfare Part 5, my first tests of missile defense in Command and Falklands Part 23.

September 15, 2021

Missile Defense Tests Part 2

Last year, I ran some tests using Command: Modern Operations to look at how the balance between ships and anti-ship missiles has changed over the years. However, I did so in a rather limited way, comparing US missile cruisers and destroyers against the SS-N-2/P-15 Styx missile. While this gave some interesting and useful information, I decided to broaden my scope, looking at both other missiles and other types of ship. I kept the basic setup from the first test, with a single ship off the coast of California, with 16 missiles fired at it. The defending ship would be the vessel most evenly matched against the missile attack in the first test, the 1991 (NTU) version of CGN-36, USS California.

To start, I re-ran my original experiment, with California facing down 16 SS-N-2/P-15 Styx missiles, fired from a bunker ashore, at a range of about 40 nm. At this range, the sea-skimming missiles pop up into radar range, then disappear again for a bit before the ship finally gets a good lock on them. The results were more or less in line with what happened during the first test: Read more...

September 12, 2021

The Standard Missile Part 2

The Standard Missile was originally developed to replace some of the USN's first SAMs, the Terrier and Tartar missiles of the 1950s. From the time it entered service in the late 60s, it was a success, with upgrades giving it more and more capability throughout the 70s and 80s. It was chosen as the primary weapon for Aegis, as well as arming older ships originally built for Terrier or Tartar. Variants were also produced, most notably an anti-radiation missile for use over Vietnam that also gave the USN an interim anti-ship missile capability in the 1970s.

An SM-2MR with a Fritz-X in the background

By the late 1980s, it was becoming increasingly obvious that the Aegis/Standard team would be incredibly effective against high-altitude targets, but less so against sea-skimming weapons. As a result, another version of the SM-2 was built, known as Block III and designed as RIM-66K/L/M (SM-2MR NTU/Aegis Mk 26/Aegis Mk 41) and RIM-67D (SM-2ER NTU). This version had improvements to the seeker and guidance sections to better pick targets out of sea clutter, as well as an improved proximity fuze. It was followed in 1991 by Block IIIA, which introduced an improved warhead and more fuze upgrades, but didn't change the designations. The end of the Cold War saw the NTU ships retired, mostly in the mid-to-late 90s, and the Mk 26 Ticonderogas axed shortly thereafter. This entirely killed off the RIM-67, and saw the RIM-66M as the only survivor of its branch, making things much easier to keep track of. It was the only version to get the Block IIIB upgrade, which saw an IR seeker added to give improved performance in an ECM-heavy environment, as well as probably some limited capability over the horizon, particularly against surface targets. Technically, both Block IIIA and Block IIIB remain the current versions, although there have been a number of upgrades over the years, including another new fuze and software changes to improve maneuverability. I suspect the version numbers have stayed the same as part of a designation engineering strategy. Read more...

September 08, 2021

The Standard Missile Part 1

In the late 60s, the USN's air defense systems were in crisis. While the first generation of SAMs, the 3T missiles, had been successfully introduced into operation, they were proving extremely unreliable in service, and the decision was made to upgrade the Terrier and Tartar missiles. These missiles used essentially the same forward section, with different motors and a separate booster for Terrier, and a new standard missile was proposed that would unify the medium range and extended-range missiles, changing only the motor and power supply1 between the two. For some reason, nobody thought to give it a better name than Standard, which remains in use to this day.

An SM-1MR is launched from frigate George Philip

In broad outlines, Standard was the same as the missiles it replaced, a rocket-propelled semi-active homing weapon designated RIM-66 for the MR (medium-range/Tartar replacement) version and RIM-67 for the ER (Terrier replacement). It used all of the same shipboard equipment, including launchers and guidance radars, as its predecessors, but the missile itself used all solid-state electronics, and replaced hydraulic actuators with electric motors. This meant that the warmup time dropped from 26 seconds for a late-model Tartar to only 1 second, while both missiles were deployed as "wooden rounds", requiring no tests over the 3-year interval between depot servicing. Range and altitude performance matched the predecessor missiles, 17 nm and 65,000' for RIM-66A SM-1MR and 40 nm and 80,000' for RIM-67A SM-1ER.2 An adaptive autopilot could handle any potential conditions of missile flight, regardless of altitude, airspeed or missile weight. Service entry came in 1968, and Standard rapidly began to replace the previous systems in service. Read more...

September 05, 2021

The Liberty Ships Part 1

In the mid-1930s, the US Merchant Marine3 was in crisis. Over 90% of its ships were the product of either the "Bridge of Ships" built to span the Atlantic during WWI or the brief shipbuilding boom in the aftermath of the war. That boom had been followed by a bust that left many shipbuilders bankrupt, and the Great Depression had compounded the damage. But as the existing vessels approached obsolescence and war clouds gathered around the world, Congress set up the Maritime Commission to organize the building of new ships, initially under a subsidy system that would compensate shipowners for the higher costs of building and operating vessels under the US flag, as well as making sure they were suitable for auxiliary service in case of war.

C2 American Forester

It soon became apparent that the Maritime Commission would need to take more dramatic steps if it was to make its goal of building 50 ships a year for a decade, and it began to develop a series of standard designs, fast, state-of-the-art vessels which could be easily converted to support the fleet in time of war. Some were contracted for directly by commercial operators, while others were ordered by the government with the intention of leasing them to the shipping lines. The centerpiece of the program were three types of general cargo ship of differing lengths and speeds, the Type C1, Type C2 and Type C3 transports. The first contracts for these ships, fast and economical by the standards of the day, were placed in 1938, and quickly expanded throughout both the traditional shipbuilders that had survived the interwar years and new yards that were opening up as the world ramped up for war. Read more...

September 03, 2021

Open Thread 86

It's time once again for our Open Thread. Talk about whatever you want, even non-military/naval stuff, so long as it isn't Culture War.

I've been talking with the PAO at NSWC Carderock, and they pointed me to this interesting video tour of some of their facilities, which I thought some of you might enjoy:

2018 overhauls are my reviews of the Boston Navy Yard and Battleship Cove, The Battleship of the Future?, Underwater Protection Part 2, Understanding Hull Symbols and Lushunkou and Weihaiwei. 2019 overhauls are Falklands Part 17, my pictures of Iowa's medical spaces, A Brief Overview of the United States Fleet, Riverine Warfare - North America, the David Taylor Model Basin and the last part on the Spanish-American War. 2020 overhauls are Powder Part 4, Merchant Ships - Tugs and offshore support and Falklands Part 22.

September 01, 2021

The Norway Campaign Part 6 - Stavanger

In April of 1940, Hitler ordered his forces to invade Norway, outflanking the British blockade in the North Sea and securing the supply of iron ore from Sweden. In most areas, the Norwegians, still expecting their neutrality to be respected, fought back in confused and halfhearted ways, and the Germans achieved their objectives relatively easily, taking Oslo despite the loss of the cruiser Blucher and seizing the town of Kristiansand on the southeastern coast.

HNoMS Æger

The other major target in that region was the town of Stavanger, home to Sola airfield, the country's first with concrete runways. It was also closer to Britain than any German-controlled airbase, and only 500 km from Scapa Flow, making it of prime interest to the Reich. Unlike other German targets, Stavanger had no fixed defenses, so the stretched Kriegsmarine sent no warships, just four transports carrying equipment for use by troops that would be flown in after Sola was captured by airborne assault. Three of the transports remained offshore, while the fourth, Roda, chose to enter Stavanger harbor under her guise as an ordinary merchant ship. Unfortunately for her, news of British minelaying on the 8th brought destroyer Æger into harbor, under the command of Kaptein Niels Bruun. Bruun's command was one of the newest ships in the Royal Norwegian Navy, and while she was small and lightly armed compared to the destroyers of the major powers, she was still the most formidable unit in the area, and her captain, unlike the vast majority of Norwegian officers, believed that war would come soon. Read more...

August 29, 2021

The Norway Campaign Part 5 - Kristiansand

On April 9th, 1940, the Nazi war machine was unleashed on Norway. Sparked by Hitler's paranoia about an Allied intervention in Scandinavia, the plan involved seizing Norway's key cities using troops carried by the warships of the Kriegsmarine. In Oslo, the plan went awry when the Oscarsborg Fortress guarding the capital opened fire, sinking the heavy cruiser Blucher, delaying the attack long enough for the King and government to escape before the Germans took the city.

Odderoya island in modern times

But Oslo was far from the only target of the German attack. Southwest of Oslo was the city of Kristiansand, also home to a major naval base. Like Oslo, it was protected by coastal defenses that dated back to the early years of the 20th century. The main fortress at Odderoya was equipped with 4 24 cm howitzers, 2 21 cm guns and 6 15 cm guns, although it had been nearly abandoned in the late 20s, and plans for reactivation and modernization had never been carried out. AA defenses were even more sparse, and mines and torpedoes entirely absent. It was slightly better-manned than Oscarsborg, and some trainees had been ordered to man the 15 cm guns of the secondary fort at Gleodden on the 8th. Most of the defenders' attention that day was taken by dealing with the sinking of the German freighter Rio de Janeiro offshore, but even this wasn't enough to alert them to the impending threat. Read more...

August 25, 2021

Naval Radar - More Advanced Stuff

Last time I took a look at radar, I touched on some of the special techniques used to sort targets from background clutter, like moving target indication. But these are only a subset of a wide array of processing methods that have been developed to improve the efficacy of military radars, and which are well worth delving into at greater length.

Radars on the island of amphibious assault ship Makin Island

The basic problem of radar is taking the raw electromagnetic signals picked up by the antenna and turning them into data that the crew can use to make decisions. From the first, engineers made improvements in this field, with PPIs being much easier to interpret than the A-scopes they largely replaced. Nor was this process confined entirely to the electronics themselves, as CICs and plotting allowed dots on a screen to be turned into tracks for the Captain or Admiral. Postwar, efforts to extract more information and automate its collection continued, producing a series of innovations which are standard on military radars today. Read more...

August 22, 2021

Lasers at Sea Part 3

In our previous two installments, I've taken a look at the technology behind lasers and their potential effectiveness. But now it's time to look instead at their drawbacks, and possible countermeasures against them.

A plane modified to defend against lasers

The simplest theoretical defense is to coat the target in mirrors, but this doesn't work as well as might be supposed. The highest reflectivity comes from dielectric mirrors, but these are specialized against specific wavelengths, and probably even specific geometry, so a more conventional mirror will be needed. This will definitely cut the range at which the laser starts doing damage, although the mirror is unlikely to continue to be particularly reflective after it starts to take damage. This, combined with the closer range at which damage starts, means that a target is likely to go from being fine to being dead quite quickly. Mirrors will still be helpful, although at the cost of raising visual signature, which might open up new guidance options for defensive weapons. Read more...