Although it has the most powerful fleet in the world, the largest carrier-based aviation, and even the most advanced anti-aircraft guns, the Imperial Navy is not satisfied, and is the first to invest in the development of anti-aircraft missiles, and the first to equip anti-aircraft missiles, and the first to use anti-aircraft missiles in actual combat.

Fundamentally, it is to protect the aircraft carrier.

After entering the jet age, large-caliber anti-aircraft guns became ornaments, and a more efficient anti-aircraft weapon was urgently needed to strengthen the fleet's air defense network.

Anti-aircraft missiles were born.

It's just that anti-aircraft missiles are not omnipotent.

As early as more than 20 years ago, the Imperial Navy discovered that it was not the air defense missiles themselves that limited the combat effectiveness of air defense missiles, but the fire control system that controlled air defense missiles, and it was mainly based on radar, that is, whether it could detect threats in time and accurately guide missiles to attack.

It was at this time that the Imperial Navy was the first to find the "Achilles heel" of the aircraft carrier battle group.

According to the deduction made at that time, only 30 anti-ship missiles were needed to break through the air defense network of the aircraft carrier battle group and take out the main warships, including the aircraft carrier.

Even if the aircraft carrier cannot be sunk, it can make the aircraft carrier incapacitated.

Although it is indeed very difficult to organize 30 anti-ship missiles to attack at the same time, to be precise, to reach the vicinity of the aircraft carrier battle group at the same time, it is not impossible to achieve it, and it is easier to launch an attack with enough anti-ship missiles than air defense.

This was the saturation attack tactic that the Western Continent Group later proposed.

As for why the Imperial Navy studied anti-aircraft carrier tactics, in addition to finding out the shortcomings of aircraft carriers and then making up for them in a targeted manner, it was also related to the enemy's aircraft carriers. The Republic of Nuland also has large aircraft carriers, and has the strength to build a strong navy and challenge the Liangxia Empire.

Against this background, the Imperial Navy began to look for ways to strengthen air defense.

As it was said at the beginning, it is not only anti-aircraft missiles that should be strengthened, but also a complete set of air defense systems with radar as the core.

At this time, an invention from the Imperial Kingdom of Narrows attracted the attention of the Imperial Navy.

That's right, phased array radar.

To put it more technically, it's called "phase control electronic scanning array radar".

Strictly speaking, the engineers of the Liangxia Empire came up with the principle decades ago, and during the Polish-Iranian War, two large phased array radars were created. At that time, the Imperial Navy even tested phased array radars on experimental ships, only to abandon them because they were too large. What was invented by the Imperial Kingdom of Sagi was a transistor that miniaturized phased array radar and had practical value.

Compared to conventional radars, phased array radar has outstanding advantages, including short scan periods and the ability to concentrate beams in one direction for greater detection capabilities. Theoretically, it is also possible to replace the irradiation radar to guide and control anti-aircraft missiles.

The birth of phased array radar directly solves the number one problem of fleet air defense.

On this basis, the Imperial Navy began to design and build the world's first air defense cruiser equipped with phased array radar at its core.

However, it was not all smooth sailing.

In keeping with its tradition, the Imperial Navy initially set its sights on more technically advanced and more difficult to implement active phased array radars.

To put it bluntly, I want to do it in one step.

It is a pity that the technical threshold of active phased array radar is too high, and the technology at that time could not make qualified RF tubes at all.

Of course, even if it could be built, it would certainly be too expensive for the Navy to afford.

If anything, this choice made the Imperial Navy take a lot of detours, which not only delayed for several years, but also caused a very far-reaching impact.

The most prominent thing is that because the price of the radar system remains high and there is no way to get more appropriations, the navy can only make a fuss about the warships, try their best to reduce the cost of building the hull, and control the overall cost of the air defense cruiser within an acceptable range.

The main thing is to let the big men of the two houses accept it.

As a result, the Navy submitted several sets of design proposals in succession, all of which were rejected in both houses of parliament because the overall cost was too expensive.

In the midst of this, the Imperial Navy gradually realized that the idea of pursuing a high and complete was very unrealistic.

And not only the air defense cruiser itself, but also the radar.

Fundamentally speaking, if the electronic technology at that time insisted on using active phased array radar, not only would the cost of the radar itself not be reduced, but also because the size and mass of the radar were too large, it would need to occupy more tonnage, and it would also put forward more stringent requirements for power supply and refrigeration, so it could only increase the tonnage of the platform, which would lead to the high cost of supporting air defense cruisers.

It can be seen that the requirements of the Imperial Navy are too high.

These problems can be solved if the requirements for radar are reduced.

It was at this time that the Imperial Navy decided to stop emphasizing the use of active phased array radars, and could accept passive phased array radars with inferior performance.

Of course, this "worse" is only compared with active phased array radars.

Compared with the machine-swept radars of the past, passive phased array radars are still very advanced.

It's just that the time delayed before will definitely not be able to be recovered.

Sadly, a large number of air defense battleships built after the end of the war, and when it was time to be decommissioned, the Imperial Navy was in dire need of new air defense cruisers.

According to the report submitted by the Imperial Navy at that time, 40 anti-aircraft cruisers were to be built within 10 years to replace the old anti-aircraft warships that were decommissioned. If you take into account the design and construction time, you must be ready to build 40 air defense cruisers in 4 to 6 years.

Obviously, this simply can't be done!

As a result, the Imperial Navy had to modernize a number of old warships and extend their service by 10 to 15 years.

The key is still to get a good grasp of the construction of new air defense cruisers.

Reduced requirements for radar systems also mean that smaller hulls can be adopted.

It was precisely because of this that the Imperial Navy could only be simplified, and the overall design was completed in less than six months by the Naval Ship Design Institute in Puzhou.

Because the cost was very low, if not cheap, the plan was immediately approved by both houses of parliament.

This is the "Qingzhou" class, the world's first cruiser equipped with phased array radar, and the largest number of cruisers built by the Imperial Navy after the war.

To say, the "Qingzhou" class was also the smallest tonnage air defense cruiser built by the Imperial Navy after the war.

Its full load displacement was only a pitiful 11,600 tons, which was not comparable to a heavy cruiser, let alone a large cruiser during the war.

In order to have a larger deck and install more anti-aircraft guns or anti-aircraft missiles to provide sufficient cover for the aircraft carrier, the air defense cruisers built by the Imperial Navy after the war never limited and controlled the tonnage, and the full load displacement was all more than 200000 tons.

Even those that were designed as destroyers and later upgraded to cruisers were as high as 15,000 tons.

The volume of 11,600 tons is simply not enough.

Quite simply, the "Qingzhou" class itself is the spare tire of the Navy.

In fact, after the construction began, the Imperial Navy did not regard the "Qingzhou" class as the main force.

At that time, the Imperial Navy still hoped that after the technology of active phased array radar matured, it would be able to build more powerful air defense cruisers.

The key is that when designing the "Qingzhou" level, everything is basically simple.

For example, the X-band active phased array radar originally developed to irradiate targets had to be canceled because of lack of funds, but in fact, the technology was not mature enough. Because the passive phased array radar cannot carry out fire control irradiation, it can only be equipped with four X-band irradiation radars for the "Qingzhou" class. As a result, even with time-sharing irradiation guidance technology, only 16 missiles can be controlled to intercept 8 targets at the same time.

That's not much.

According to the establishment of the Imperial Navy, an aircraft carrier battle group has only 2 air defense cruisers at most, and it has to undertake almost all long-range air defense tasks, so according to the calculation of dealing with 30 anti-ship missiles, a cruiser must have the ability to intercept at least 15 targets at the same time.

The air defense cruisers previously designed by the Imperial Navy had 16 fire control channels, and the "Qingzhou" class was only half of that.

In addition, the Qingzhou class is equipped with the DK-8 "Sun-By-Day" medium- and long-range anti-aircraft missile with a range of only 120 kilometers, instead of the XDK-9 with a range of 200 kilometers. Also limited by the size of the hull, the "Qingzhou" class only installed a set of twin launch systems on the front and rear decks, and can only launch four missiles at a time. Although its reload time is only 15 seconds, it is clear that the fire density is seriously insufficient.

That is, there are only 2 launchers, and only 4 irradiation radars are installed.

At the time of design, in order to reduce the displacement by 100 tons, even anti-ship missile launchers were abandoned. If it weren't for the resolute opposition of some senior generals, who had the design institute revise the plan and install two sets of anti-ship missile launchers on the stern platform before the construction began, the "Qingzhou" class would probably become the first type of cruiser in the Imperial Navy, or even the first in the world, that does not have the ability to dominate the sea.

However, this is not entirely unreasonable.

The abandonment of anti-ship missiles is actually to maintain the more important anti-submarine combat capability.

For the warships of the Imperial Navy, naval supremacy was never the main task.

Don't forget, the Imperial Navy has the most powerful carrier-based aviation in the world, with hundreds of carrier-based attack aircraft and hundreds of carrier-based fighters capable of carrying out strike missions, so even if you want to carry out sea domination missions against the enemy's fleet, it is simply not the turn of escort warships.

During World War II, the Imperial Navy rarely used warships to carry out naval combat missions.

Whenever possible, the fleet commander would first consider sending out carrier-based aviation to take out enemy warships with bombs and torpedoes, now air-launched anti-ship missiles.

Escort warships had only two duties, anti-aircraft and anti-submarine.

If anything, the latter is more important.

Before the advent of anti-ship missiles, especially heavy supersonic anti-ship missiles, the air defense threat faced by the Imperial Navy was not serious.

Relying on a large number of carrier-based fighters, it is possible to deal with attack aircraft with iron-hulled bombs.

In contrast, the threat from below the surface has never abated.

According to the statistics made by the Imperial Navy, nearly half of the aircraft carriers lost in the last war were sunk by submarines, and not so many were sunk by planes!

Although the Imperial Navy has the world's largest underwater fleet and the best performing large attack submarines, the pressure on anti-submarine has never been reduced, so there is an unwritten rule in the Imperial Navy that any ocean-going warship must have complete anti-submarine warfare capabilities.

And not only anti-submarine frigates, but also anti-aircraft cruisers.

The universal destroyers of the Imperial Navy are almost all genuine anti-submarine destroyers, while there are only a few real air defense destroyers.

It is precisely for this reason that if we have to make a trade-off, then what we must give up is the ability to dominate the sea.

All in all, the Imperial Navy, having no other choice, put the "Qingzhou" class, which was originally used as a spare tire, in the leading role.

Fortunately, the pace of technological progress has far exceeded everyone's expectations.

Before the first batch of eight ships was built, a vertical launch system was born that could greatly increase the launch speed of missiles, and the density of firepower was no longer a problem.

Starting from the 9th ship, the "Qingzhou" class replaced the two sets of missile launchers in the front and rear with two sets of vertical launch systems with a total of 128 units arranged in front and behind the superstructure, and later the anti-ship missile launchers were also dismantled. As for the first 8 ships, they were all improved during the mid-term overhaul.

Subsequently, a mid-course radio command guidance system was developed, which doubled the number of missiles guided at one time to 32 without increasing the number of irradiated radars, basically meeting the tactical target of intercepting 16 targets at the same time proposed by the Navy.

Of course, the DK-8 "Day by Day" also increased the range by adopting a booster of greater size.

The latest DK-8D, the maximum range has already exceeded 200 km.

In addition, the Navy is developing high-speed data links.

Theoretically, in the future, carrier-based early warning aircraft such as the "Finger-6C" can control and guide anti-aircraft missiles launched by warships to intercept targets beyond the line of sight.

In this way, it will be possible to get rid of the limitations of the irradiation radar and continue to increase the range of anti-aircraft missiles.

The key is that under the control and guidance of carrier-based early warning aircraft, air defense missiles can intercept targets below the sea antenna and are no longer affected by the curvature of the earth's surface.

All in all, thanks to technological progress, the combat effectiveness of the "Qingzhou" class has been greatly improved.

Because it can provide sufficiently effective air defense cover for aircraft carriers, and its anti-submarine combat capabilities are also very powerful, the problem of insufficient tonnage has long been left behind by the Navy.

However, the lack of tonnage limited the improvement potential of the "Qingzhou" class and also lowered the standard of living of officers and men.

However, these are bearable, after all, the "Qingzhou" class is cheap enough.

So far, the Imperial Navy has ordered 42 "Qingzhou" class ships in three batches, 34 of which have been delivered and put into service, of which 26 are in the aircraft carrier battle group, 8 are in the process of seaworthiness acceptance before service, and 8 are under construction, and the Imperial Navy is likely to increase the number of orders.

According to the shipbuilding plan drawn up last year, the total number of air defense cruisers will reach 86, and the other 64 will all be of the "Qingzhou" class, except for the 22 old cruisers that have not yet reached the retirement period, so even if the war does not break out, at least 22 such cruisers will have to be ordered.

Of course, it is the radar that makes the "Qingzhou" class.

In the past, it was also the radar that limited the scale of the construction of the "Qingzhou" class.

Fortunately, after the formation of the scale effect, not only the cost of the hull has been reduced, but the purchase price of the radar has also dived.

Crucially, the need for air defense is never-ending.

It was precisely because of this that the Imperial Navy had to seriously consider using phased array radars on more warships in order to improve the fleet's comprehensive air defense combat effectiveness!