Iron Sonata of World War II

Carl Vinson was later able to name a nuclear-powered aircraft carrier, which I strongly suspect was in recognition of his contribution to the Navy in Congress.

Chapter 49 Opportunity

In fact, when Helena saw the performance manual of the F4 engine provided by Mercedes-Benz, Helena already had a rough guess in her heart.After seeing the actual F4 engine of Mercedes-Benz, Helena can basically conclude that Mercedes-Benz is still the same Mercedes-Benz in history, and the F4 engine is still the same F4 engine in history.

In the history of the last plane, Daimler-Benz developed the DB4 series engine based on the F600 engine. This engine later became the heart of the BF109 series of fighter jets produced by Germany in World War II.During the entire war, the BF109 series fell in love with their old rivals, the British "Spitfire" series of fighter jets, with this heart in mind.

In the early days of the world war on the upper plane, compared with the "Merlin" series engines used by the "Spitfire" fighter jets, the DB600 series engines actually had certain advantages in terms of overall performance.For example, during the British Air War, the maximum power of the DB109A used by the German BF601E was basically the same as the "Merlin" engine developed by Rolls-Royce at the same time, but the weight was much lighter than the "Merlin", and there was no "Merlin" The problem of easy oil cut-off during violent maneuvers (please note that even in this period, DB601A can only be said to have certain advantages, but not to surpass the opponent in an all-round way. After all, the "Merlin" engine also has its own advantages, such as the "Merlin" engine. The power attenuation with altitude is not as obvious as DB601A).

During this period, the excellent performance of the DB601 made the BF109 one of the most advanced fighters at the same time. Marshal Goering assisted, but still can't take advantage of BF1.

However, the above mentioned are only the first half of the competition, and the magic turning point in the second half will come soon.As the war progressed, the BF109 and the Spitfire continued to develop.In order to meet the increasing power requirements of fighter jets, the DB600 series engines and the "Merlin" series engines naturally need to be continuously improved to increase the maximum power.

However, at this time, a strange thing happened. Compared with the "Merlin" series engines whose performance has been greatly improved, the improvement of the DB600 series is always like an old woman with bound feet, and it is difficult to take a step forward.In the middle and late stages of the war, the performance of the "Merlin" engine had completely overwhelmed the DB600 series, completing a perfect counterattack.

For example, in 1943, the 1710-horsepower "Merlin" 63 engine was already equipped with the "Spitfire" fighter jets, while the DB605A at the same time could not even reach the design index of 1475 horsepower (due to the problem of carbon accumulation, it was restricted from further development. Air pressure, the actual usable power is only 1350 horsepower)!

这看起来似乎很不科学，要知道DB600系列一开始就有33.9升的排气量（DB605A更是增加到了35.8升），而“梅林”系列的排气量只有27升。结果却是排量更大的DB600系列发动机的改进潜力远远不如排量更小的“梅林”系列发动机！

In military forums in previous lives, every time it was mentioned that Mercedes-Benz’s DB600 was not as good as “Merlin” in terms of follow-up power improvement, many military fans would emphasize the lack of rare metals and high-grade aviation fuel in Germany in the middle and late stages of the war.But in Helena's view, this is not the root of the problem!The lack of rare metals and high-quality fuel has certainly brought some troubles to the improvement of DB600, but Mercedes-Benz chose a dead end with no future in the initial design, which is the key to the lack of improvement potential of the DB600 series!

If you want to know why the DB600 series is so strong in the early stage and why it is so good in the later stage, you must know the design features of the DB600 series.In Helena's view, compared with other liquid-cooled engines of the same period, the DB600 series has three main design features:

The first feature is to use a higher compression ratio to increase the mean effective pressure of the engine.Taking DB601 as an example, its compression ratio is as high as 6.9, which is much higher than the 6.0 of "Merlin".The designers of Mercedes-Benz believe that the higher compression ratio of the engine can replace part of the role of the supercharger. Even if the supercharger ratio of the supercharger is not high, the engine can also get a higher average effective pressure.

The second feature is the replacement of the carburetor with a mechanical direct fuel injection system.Starting from DB601, DB600 series engines began to adopt mechanical direct injection technology.That is to say, the fuel is directly injected into the cylinder and mixed with the intake air, instead of forming a mixed gas in the carburetor and then entering the cylinder like a carburetor engine.This design allows the DB600 series to have no worries about oil cut-off under negative overload conditions, while the early models of the "Merlin" that used carburetors on the opposite side had a serious problem of negative overload oil cut-off (later, the "Merlin" engine gave the carburetor A current limiting ring is installed on the device, which can allow short-term negative overload flight, which partially solves the problem of negative overload fuel cut-off).

The third feature is the replacement of the engine intercooler with excess fuel injection.We all know that in the process of compressing air, air molecules will gain internal energy, which will increase the temperature.When the air passes through the supercharger of the engine, the temperature will also rise due to compression. At this time, if an intercooler is not installed between the supercharger and the intake manifold to cool the supercharged air, the engine will have It may be that the gasoline is ignited in advance due to the high temperature, which then induces engine knock.In order to reduce the weight of the engine, the DB600 series engine is not equipped with an intercooler, but relies on the direct injection system to inject excess fuel into the cylinder to cool the cylinder wall first, and then the excess fuel can absorb part of the heat during the gasification process, so that Just can suppress engine deflagration under the situation that omits intercooler.

These three characteristics of the DB600 series did bring a lot of advantages to this engine in the early days of the war, but the replacement of the supercharger by the high compression ratio part and the intercooler by the rich oil injection part The seemingly clever approach has become an endless shackle in the future improvement of DB600.This shackle is mainly reflected in two aspects:

The first aspect is the problem of carbon accumulation.Friends who know cars should know that direct injection engines are relatively easy to accumulate carbon. Moreover, the accuracy of fuel injection control during World War II could not be comparable to today's.

However, this is not the end, and now we have to add the fuel-rich combustion used to omit the intercooler. Due to the low air-fuel ratio, the air inhaled by the engine is not enough to oxidize all the fuel, which becomes "easy to deposit carbon". Quadratic!

However, this is not the end. Due to the higher compression ratio, the combustion pressure of DB600 is higher than that of "Merlin", and the higher the combustion pressure of the fuel, the more prone to coking, so this becomes "easy to deposit carbon". " to the third power!

The second aspect is the question of boost potential.Since the DB600 series adopts a higher compression ratio and does not have an intercooler at the same time, this will bring a lot of trouble to the engine's future supercharging.

If the boost ratio is forcibly increased, it will inevitably lead to two results: higher combustion pressure and higher intake air temperature!This can further exacerbate carbon buildup and deflagration problems.Ever since, during World War II, the DB600 series could only look at other people's second-stage superchargers with better high-altitude performance with envy and envy, and then look at my shabby first-stage supercharger, the tears of the DB600 series were rushing to Dirty!

In addition to the above two main problems, the fuel-rich combustion of the DB600 will also bring higher fuel consumption. This high-fuel consumption engine matches the BF109, which has a relatively small internal fuel tank. ...

In short, Daimler-Benz's design looks very clever and tricky, but it always has to be paid back when it comes out!Although the opportunistic approach can bring huge benefits in a short time (such as greatly reducing the weight of the engine), the technical route of killing chickens and eggs will sacrifice the future upgrade potential of the entire series of engines.

Looking at the Daimler-Benz that has changed to another plane and still remains unchanged, Helena has quietly sentenced the Mercedes-Benz F4 engine to death. This thing is a trap covered with flowers. Compared to Helena The brain pits of the Germans filled in before are even more confusing!

In the last plane, the Luftwaffe stepped into the big hole of Daimler-Benz. When the habitual carbon accumulation problem of the DB600 series was finally cured, the timeline was pushed back to 1944. What did Germany do at this time? it's too late...

Chapter 50 Cynicism

Here, the Daimler-Benz personnel are still talking to the military representatives in high spirits, showing off the superiority of their product performance. Incisively and vividly, they will never tell you how many sinkholes are hidden under the glamorous performance data of the product!

For example, in the last plane, the DB600 engine and the "Merlin" engine basically made their first flight at the same time (both in 1935), and the maximum power is basically the same (both about 1000 horsepower).At this time, if these two engines can be chosen by buyers, most buyers will probably jump into the pit of Mercedes-Benz and choose DB600.After all, the DB600 at this time is more than 20% lighter than the opponent when the output power is basically the same. This advantage is too tempting.

In her previous life, Helena hated unscrupulous merchants very much, and naturally she will not sit back and watch Mercedes-Benz harm consumers in this life.So Helena spoke to the Mercedes entourage: "May I ask your company a question?"

"Dear lady, please speak." The escort of the Mercedes-Benz company said kindly.

"What I want to ask is, if your engine needs to further increase the output power in the future, how will your company plan to solve the problems of knocking and carbon deposition while the intake pressure is greatly increased?" Helena also smiled asked.

"This, this, this..." The accompanying personnel of the Mercedes-Benz company, who were eloquent just now, suddenly stuttered, like a tape recorder with a few tapes stuck.The military representatives who came to visit are not professionals, and may not be particularly familiar with the details of technical implementation, but this does not mean that they are fools. Seeing the stammering appearance of Mercedes-Benz, everyone understands three points in their hearts , with scrutiny and suspicion in their eyes.At this moment, Helena still had a smile on her beautiful face, but in the eyes of the accompanying personnel of the Mercedes-Benz company, they seemed to see the ferocious devil in hell.

It's cool when you spray it, and it's cool when you spray it all the time!The problem of not being able to stop once she started to spray on various forums in her previous life has been perfectly inherited by Helena in this life.

"It's a high boost ratio, fuel-rich combustion, and no intercooler. If we need to improve engine power and high-altitude performance in the future, what are you going to do?" Before the Mercedes-Benz company's escorts could figure out how to get away with the wording , Helena started a new round of verbal attacks: "Increase the speed? Increase the impeller of the supercharger? If it doesn't work, increase the displacement? If it doesn't work, spray methanol solution? Do you have any other methods? Do you have any?"

"We can still..." The accompanying staff of the Mercedes-Benz company had almost collapsed at this time, and they were also very desperate when they suddenly met a knowledgeable buyer.

"Yes, I have thought of a perfect solution!" Helena clapped her hands suddenly and said.

"What method, let's talk about it." A military representative asked eagerly, perhaps not hearing the sarcasm in Helena's tone.

Helena tilted her head playfully, and replied solemnly: "Knocking and carbon deposits are actually not a big deal. Don't you hear that the engine is too fat, so use fuel! As long as the grade of fuel is high enough, knocking can be improved. ;As long as the sulfur content of the fuel is low enough, carbon deposits can be improved! So as long as we equip this Mercedes-Benz engine with an extremely low-sulfur fuel with an equivalent octane value of 100 or more, this engine can still be rescued.”

If anyone still can't hear the sarcasm in Helena's words at this time, it's his IQ problem.The accompanying personnel of the Mercedes-Benz company watched the attitude of the military representatives suddenly change from enthusiasm to coldness, and knew in their hearts that the bidding was likely to be completely overturned.If Mercedes-Benz's grievances could kill people, then Helena should have died at least a hundred times at this time.

However, Helena didn't seem to feel the resentment from the accompanying staff of the Mercedes-Benz company, and continued to speak solemnly: "The lower the sulfur content of the fuel, the less likely it is to deposit carbon, so I suggest that the Farben The coal direct liquefaction project under construction has been stopped, because the fuel oil obtained from direct coal liquefaction has too high sulfur content, which is not worthy of our noble and glamorous Mercedes-Benz company!"

At this time, the accompanying staff of the Mercedes-Benz company looked at Helena from resentment to pleading, as if to say: "Please, stop talking, at least leave us a pair of pants for the Mercedes-Benz company."

"If you want to obtain fuel oil with a sufficiently low sulfur content, you must use the best light sweet oil ("sweet oil" refers to low-sulfur crude oil with a sulfur content of less than 0.5% in petrochemical industry) as a raw material for refining. Currently There are only three oil fields in the world that can produce a large amount of light sweet oil, namely: the Baku oil field in the southern part of the Soviet Union, the Texas oil field in the western United States, and the Brent oil field in the northern United Kingdom! So as long as Germany occupies these three oil fields in one fell swoop There is a big oil field, so why don’t you worry about the lack of good oil for the Mercedes-Benz engine?”

Helena's ridicule gave the Mercedes-Benz company, which had already been knocked down, the last footstep.In this way, the famous Daimler-Benz DB600 series in the last plane was wiped out in the womb by Helena before it could be born.A large number of German pilots, including the German ace pilot Hans Joachim Marseille from the previous plane, were killed by the carbon build-up problem of the DB600 series engines. They still don’t know what Helena just said , indirectly saved his life.

The Mercedes-Benz engine with the highest performance parameters was accidentally knocked into the dust by Helena. This made Maybach and Junkers, who thought they had little chance of winning, overjoyed, and hurriedly introduced their works to the military.But this time, Maybach and Junkers have become more honest. They basically have one thing to say about the performance, advantages and disadvantages of their own works. No one dares to use Mercedes-Benz's tricks to fool consumers anymore.

Accompanied by a group of technicians and company executives, a group including Helena walked to the display area of ​​Maybach and Junkers.With the previous experience of being almost killed by a glamorous Mercedes-Benz engine, everyone became more cautious.The military representatives did not make a quick decision, but turned their attention to Helena for consultation.From everyone's point of view, Helena is obviously an expert in this field!But in fact, apart from being able to look up the data in the system, Helena just has more experience and lessons than them that countless soldiers in the history of the previous plane exchanged their lives for.

Huh?Is this the work of Maybach and Junkers?Interesting.After looking at the engine parameters and real objects of Maybach and Junker, Helena nodded secretly.

The author has something to say: After the 45th chapter was revised, it finally passed the second trial.

Chapter 51 Deja vu

Compared with the opportunistic Daimler-Benz, the products of Maybach this time seem to be quite satisfactory.

Maybach's disastrous defeat in the bidding for the engine of the future chariot has greatly touched the Maybach company.More importantly, through the previous bidding for chariot engines, Maybach has deeply realized that Helena's opinion has a huge influence on the military's weapons procurement. Fang's bidding is a sure thing.

So how to make your products be favored by Helena?For this purpose, Maybach also held an internal seminar to analyze in detail Helena's tendency in engine selection for Army vehicles.The conclusion is that things that are too extreme are often not recognized by Helena. On the contrary, designs that are balanced, reliable, and have great upgrade potential are easier to pass!

With the above analysis, Maybach immediately put it into practice. After losing the order for the chariot engine, Maybach could not stand the second fiasco.So after more than a year of hard work by Maybach, the result was finally produced before the aero-engine bidding came, which is the prototype presented in front of Helena.

This Maybach prototype has a displacement of 32 liters and uses an inverted V-shaped 12-cylinder with the cylinder head facing down.The engine supercharging device adopts a single-stage two-speed supercharger with an intercooler.The compression ratio is not too high at 6.0, which leaves enough room for further boosting in the future.The air-fuel ratio is 17, which is slightly biased towards lean fuel combustion, which is also conducive to improving the problem of carbon deposition.In general, except for the fact that the cylinder head is arranged downward, the technical route of this engine has a little bit of the British style of the previous plane (the British in the previous plane prefer liquid-cooled aero engines with the cylinder head facing downward. superior).

Helena is generally satisfied with this Maybach product.Helena believes that thanks to the relatively balanced displacement of 32 liters, if this engine is well developed, its potential will be greater than that of the "Merlin" series engines with a displacement of 27 liters on the previous plane (the power of the "Merlin" engine The biggest shackle of the upgrade is the small displacement, so the British replaced the "Spitfire" fighter with a larger displacement "Griffin" series engine in the latter part of the war).

However, when looking at the actual Maybach engine, Helena found a problem: the supercharger and intercooler of the Maybach engine are not installed at the rear of the engine body like most engines, but are arranged in a very awkward way on the side of the engine block.

At this time, Helena already had a guess in her mind, and when she turned to the front of the engine and looked at the big hole in the engine reducer shaft, Helena's guess was immediately confirmed.It turns out that the hole on the shaft of the engine reducer is for shooting the central axis cannon of the fighter jet in the future, and the supercharger and intercooler are placed on the side of the engine to free up space at the rear of the engine and use it To install the center axis gun.

The central axis gun is a cannon installed on the central axis of the aircraft by some fighter jets during World War II. The central axis gun is located directly in front of the driver, and the barrel passes through the gap between the two cylinders of the V-shaped engine.When firing, the bullet passes through the reserved hole in the shaft of the engine reducer and exits the fairing in the center of the propeller.

Is the center axis gun any good?Of course it works!The biggest advantage is that the shooting direction of the shaft gun is facing the direction of the aircraft, which is undoubtedly the most beneficial position for the cannon to be aimed at by the pilot.

In contrast, the wing guns installed in the middle of the wing are too far away from the central axis of the aircraft. In order to ensure the firepower density, the gun barrels cannot be pointed straight ahead. The inner corner of the plane allows the shells fired by the wing guns on both sides to meet hundreds of meters in front of the aircraft, which puts forward higher requirements for the pilot's aiming experience.

If the cannon is installed on the fuselage or wing root, since it is very close to the central axis of the aircraft, the requirements for the pilot's aiming experience are not as high as that of the cannon placed in the middle of the wing.But because there is a high-speed rotating propeller directly in front of the aircraft, this arrangement must design a shooting coordinator to ensure that the shells are fired from between the rapidly rotating propeller blades, otherwise the fired shells will destroy the propeller of the own aircraft.

Although the shaft gun is very good, and Helena herself likes the shaft gun very much, she still does not plan to install the shaft gun for future German fighter jets.The reason is also very simple. Although the axis gun is the most convenient cannon installation position for the pilot to aim at, if we zoom in on the entire fighter jet, the axis gun may not be the most favorable choice.

First of all, the shaft gun is not good for the arrangement of the engine. In order to accommodate the shaft gun, the booster device that should have been installed at the rear of the engine was forced to move to the side of the engine.You must know that in the last plane, the DB109 engine used by the German BF601 fighter jet only had a one-stage supercharger, and there was no intercooler, so it was a very painful thing to arrange the supercharger like this.In this plane, Helena will definitely not be satisfied with the first-level supercharging in the future.

Secondly, the shaft gun is not good for the protection of fighter jets. During World War II, in order to protect the engine and pilots, protective partitions were generally installed between the engine compartment and the cockpit. The BF109 had to have openings in the protective bulkhead in order to mount the shaft gun, which destroyed the integrity of the protective bulkhead.This makes it easier for the fire to quickly invade the cockpit once the engine catches fire.

In short, in Helena's view, although the shaft gun is very useful, we should not only focus on the shaft gun itself, but should consider it in the overall performance of the fighter. No matter how good the shaft gun is, it is only a part after all. best point.In Helena's view, the loss outweighs the gain without compromising the pursuit of the overall optimum for the sake of the local optimum!

So Helena asked the Maybach staff: "Did you put the supercharger and intercooler on the side of the engine to prepare for the installation of axle guns in the future?"

The accompanying personnel of the Maybach nodded quickly. In their opinion, the ability to install the shaft gun is undoubtedly a major advantage of their products over those of Junkers.This advantage became even more obvious after the Mercedes-Benz company, which could also install axle guns, was eliminated.

"The central axis gun does have many advantages, but we can also achieve similar effects by installing the cannon on the nose or at the root of the wing. Although we need to prepare an additional set of shooting coordination devices, the engine has been liberated, so that we can You can make the power stronger!" Helena continued to be serious: "I hope you can always remember that the engine is the irreplaceable heart of the aircraft! And the axle gun is not irreplaceable! For the aiming brought by the axle gun Convenience on the fly, the loss of engine performance and pilot safety, is completely chasing after the penny!"

The military representative expressed support for Helena's words, and Maybach also hurriedly said that he would go back and modify the design immediately.

Now the only players left on the field are Junkers, which is the finale. Helena is actually looking forward to the products of Junkers. The engine can really be regarded as a clear stream in the engine design world of the Third Reich, which is full of brain holes.

So what kind of design will the Junkers company come up with in this plane?

Chapter 52 High and Low Matching

Junkers did not live up to Helena's expectations. After listening to the introduction of Junkers' new engine, Helena couldn't help giving Junkers a thumbs up.Because on Junkers' new engine, Helena vaguely saw the shadow of Jumo211/213 in the previous plane.

If you want to ask Helena from the previous plane: Regarding the aviation piston engines that were widely equipped in Germany during World War II, which one do you like best?Helena will not hesitate to give the answer of the Jumo213 series.

In the previous plane, the Jumo213 series engines were designed by Junkers and were mainly used in the later models of FW190 and Ta152.The output power of the machine can reach 1750 horsepower without nitrous oxide booster; if nitrous oxide booster is used, the power can be increased to 2050 horsepower in a short time.Many people may disagree with the data of 1750 horsepower. After all, the "Griffin 14" engine used by the British on the "Spitfire 65" fighter jet has a maximum power of 213 horsepower, which is more powerful than Jumo2035.

不过也请不要忽略，英国“格里芬65”的2035马力最大功率，是在使用高质量的100/130号航空汽油时才能达到的。而Jumo213从头到尾都只有寒酸的B4航空燃油（大致只相当于英美的90号航空汽油）可用。二战结束后，法国人用100/130号航空汽油测试了Jumo213的性能，发现此时的Jumo213在不加力功率就可以达到2100马力，加力功率更是高达2300马力，这个数据比起盟军的同级别发动机也完全可以称得上优秀了。

其实德国倒也不是没有性能大致相当于英美的100/130号航空汽油的C3燃油，但这些宝贵的C3燃油大多被宝马的Bmw801型14缸气冷发动机拿走氪金去了（从Bwm801D开始，C3燃油就成了宝马这个败家子全系发动机的标准燃油，毕竟气冷发动机对燃油的要求比液冷发动机要高得多）。于是，姥姥不疼舅舅不爱的Jumo213就只能喝B4这样的劣质燃油了。

……

Now let's go back to the bidding site. If Helena can be called satisfied with the design of Maybach, then she can be called very appreciative of Junker's design.

This engine of Junkers is still a water-cooled 12-cylinder inverted V-shaped design, using direct injection technology (in fact, the Jumo210G engine of Junkers was the first engine to use direct injection in the cylinder in history), with a 35-liter The displacement is larger than that of Mercedes-Benz and Maybach; the compression ratio is 6.4, which is between Mercedes-Benz and Maybach; the supercharging method is a one-stage two-speed supercharger with an intercooler similar to Maybach.However, these are not the things that satisfy Helena the most. What Helena is most satisfied with is the innovation of Junkers in details:

First of all, on this Junkers engine, the single-row cylinder and one side of the crankcase are machined as a whole, so that only the left and right parts need to be bolted together to form a complete engine block.Most engines need to be divided into three parts: two banks of cylinders and a crankcase.

Secondly, Junkers made the engine radiator into a ring shape and placed it at the front of the engine. Although this will make the engine length longer, the cross-sectional area of ​​​​the engine will be reduced, so that the nose part can be changed when installing the engine. It is more rounded and slender, which is beneficial to reduce aerodynamic resistance.

So far, all the products of the three companies have been visited.For Mercedes-Benz's F4 engine, Helena is ready to give up treatment. After all, there are too many problems in the womb of Mercedes-Benz. If you have to modify them one by one, the workload and expenditure will be the same as developing a new one engine.So you can only choose between Maybach and Junkers products.

Regarding this question, Helena said: Children only do multiple-choice questions, and of course adults need all of them (Voice-over: Helena, you are underage.)!

In Helena's vision, Germany will not have only one main fighter in the future, but will still form a pattern similar to the high-low match of FW190 and BF109 as in history.Among them, the high-end machine can use Junkers engine as in history, and the low-end machine can use the Maybach design.In fact, if you look at it from Helena's point of view, although the design of Maybach and Junker can be said to be quite good, there are still many things that need to be improved.But now it has just entered 1930, and Germany has enough time to perfect the two engines.

Helena's opinions on the development direction of the two engines are as follows:

20. The engine of Junkers should increase the maximum displacement by about 213% to allow greater performance potential.In history, Jumo165 had to use super high piston speed in order to increase performance under the condition of limited displacement (the engine with 3200mm piston stroke actually reached a high speed of 3700 rpm, Junkers’ plan also had a monster of [-] rpm ).Although Junker is bold and there is nothing wrong with such a high-speed piston, there are still some adverse effects: for example, in order to ensure the strength of the crankshaft, the crankshaft has to be made very thick; another example is to prevent the piston from overheating and locking , more margin must be left between the piston and the cylinder, which increases the oil consumption (the German engine's ancestral burning of oil is also related to the too fast movement of the piston).In this case, allowing Junkers to increase the displacement moderately is also conducive to balancing the excessively high speed.

4. The supercharger with hydraulic torque converter on Mercedes-Benz’s F600 engine should continue to develop, and Junkers should cooperate with Mercedes-Benz on this technology (although Mercedes-Benz’s DB[-] series is relatively poor, it is not without bright spots. Although its mechanical supercharger has only one stage, it is driven by a hydraulic torque converter, so the speed of the impeller of the supercharger can be adjusted steplessly according to needs, so the curve of the power of the Mercedes-Benz engine changing with height is better than that of pure gear transmission. Supercharger is more gentle).

[-]. Junkers should try turbo-mechanical compound supercharging technology on high-end engines, such as adding a turbo-assisted supercharger before or after supercharging to greatly improve the high-altitude performance of the engine.

Fourth, Maybach should also cooperate with Mercedes-Benz to study the two-stage mechanical supercharging technology with hydraulic torque conversion.

Everyone had no objection to Helena's proposal, and the matter was settled like this.

In short, as a result of this bidding, Maybach and Junkers have gained a lot, while Mercedes-Benz has become the biggest loser, and can only rely on the technical advantages of the torque converter supercharger to get a little leftovers.

However, Helena said that Mercedes-Benz has won a large order for German car engines with Friedrichshafen before, and if it wants to eat the aero engine market, it may not be exhausted, so Mercedes-Benz still has a bright future in car engines. business.

Chapter 53 Cruise Race

In Hamburg in December 1930, a huge cruise ship with the striking "Bremen" written on its bow side was slowly entering the port, and a brand-new blue ribbon over 30 feet long was fluttering in the wind from the top of its mast.This is the ocean-going high-speed cruise ship "Bremen" belonging to the North German-Lloyd company.

Since the 19th century, the Blue Ribbon has been the highest honor a cruise ship can receive. This honor is won by a cruise ship that can cross the Atlantic Ocean at the fastest average speed.Whenever a transatlantic cruise ship breaks the speed record, a blue streamer can be tied to the mast until another cruise ship breaks its record.

The cruise ship "Bremen" with a blue ribbon slowly approached the pier in the Port of Hamburg, which was already crowded with crowds of onlookers.Half a month ago, the "Bremen" just broke the westbound speed record on the Atlantic Ocean with an average speed of 32.05 knots, and now the "Bremen" broke the eastbound speed record on the Atlantic Ocean with a speed of 32.83 knots. The 32-foot-long streamer on the top of the mast symbolizes the average speed of 32 knots when it crosses the Atlantic Ocean.

By the way, since the currents in the North Atlantic Ocean flow from west to east, the same ship crosses the Atlantic from west to east with the current, and the speed is generally faster than when it sails against the current from east to west.

After World War I, with the recovery of the economies of various countries, the "cruise race" that was once interrupted by the war became active again.Especially after the "Washington Treaty" in 1922, the arms race of various countries around naval capital ships was sealed by a treaty, temporarily entering a dormant period called "naval holidays".The major industrial countries saw that since the martial arts can't be played now, let's do some writing.As a result, large high-speed cruise ships have naturally become the main battlefield for the competition of shipbuilding industries in various countries.

In the 20s and 30s of the previous plane, industrial countries such as Britain, Germany, Italy, France, and the United States successively joined the competition for the blue ribbon.After all, if the country's cruise ships can hang the blue streamer, it is a great affirmation of the overall strength of the country's shipbuilding industry.The potential political value and economic value behind it will be immeasurable!So everyone has fun.

In the last plane, the German cruise ship "Bremen" also won a blue ribbon. On July 1929, 7, the "Bremen" crossed the Atlantic in a record of 16 days, 4 hours and 17 minutes, with an average speed of 42 knots.In the following years, "Bremen" and her sister ship "Europa" chased after each other, alternating with blue streamers.This situation lasted until 27.83, when the Italian "King" ran an average crossing speed of nearly 1933 knots, and finally took away the honor of the pair of sister ships!

It is worth mentioning that the last high-speed cruise ship on the previous plane to obtain the "Blue Ribbon" was the "United States" built by the Americans in 1952. The power plant of the "United States" actually came from "Iowa". The USS Illinois, the fifth ship of the USS-class battleship, due to the cancellation of the construction plan of the USS Illinois, the already built power system was taken over by the USS United States.After further improvement, its power was increased to 24 horsepower. On July 1952, 7, the "United States" crossed the Atlantic at an average speed of 3 knots!During a light-load test voyage, the "United States" even ran at a top speed of 35.59 knots (the krypton gold boss can't afford to mess with it)!However, the "United States" is only a flashback of high-speed cruise ships. After the end of World War II, with the gradual rise of transoceanic airlines, super cruise ships with high-speed passenger transportation as their main mission gradually declined.In the era of Helena's travel, the main function of large cruise ships has long been a sightseeing ship, and the pursuit of speed is no longer so persistent.

On this plane, due to the influence of Helena, Germany's steam power technology and ship rent reduction technology have made great progress.Therefore, the "Bremen" class high-speed cruise ship directly borrowed and doubled the power system of the cutting-edge "Konigsberg" class light cruiser. , into twelve boilers and four steam turbines driven by four shafts, the rated power is as high as 192000 horsepower, and the actual output power is expected to reach more than 21 horsepower.

The powerful output power and the slender hull allow the "Bremen" class super cruise ship with a standard displacement of 42000 tons to reach a maximum speed of more than 36 knots under normal displacement (it is impossible to load more cargo when crossing the Atlantic Ocean maintain this speed), this speed is expected to exceed the super cruise ship "Normandie" under construction by the French and the "Queen Mary" under construction by the British.

Of course, Helena also knew about the construction of the "Bremen" and "Europa", not only knowing, but also being deeply involved in it.The reason why Helena attaches so much importance to high-speed cruise ships is mainly because large high-speed cruise ships are not only means of transportation in peacetime, but also very valuable military resources in wartime.

Combining the military practice of large cruise ships in World War I and World War II in the previous plane, Helena believes that in addition to being used as logistics ships such as troop carriers, there are two main destinations for large cruise ships during wartime: the first is to be transformed into auxiliary ships. Cruisers, the second destination is to be converted into aircraft carriers.

Let’s talk about the first of the two destinations first. Converting a large cruise ship into an auxiliary cruiser is undoubtedly a way to use it with a lower conversion cost.You don't need to do major surgery on the hull, you just need to install a few deck guns and pull it out to perform tasks.

However, judging from the practice of war, the effect of doing so seems to be unsatisfactory.Although compared with auxiliary cruisers converted from ordinary merchant ships, auxiliary cruisers converted from large cruise ships have faster speed, longer voyage, and relatively better damage resistance, but the appearance characteristics of large cruise ships are too obvious (after all, the number of large cruise ships in the world It is relatively rare, and it is almost impossible to make yourself disappear from the crowd), thus losing the concealment that auxiliary cruisers rely on most.In the World War I on the last plane, Germany once installed artillery on the large cruise ship "Trafalgar Cape" to perform the task of breaking the border. As a result, before hunting a merchant ship, it was caught by the British army while adding coal One hit and was sunk.What is more interesting is that the "Carmania" that sank the "Cape Trafalgar" was also an auxiliary cruiser converted from a large cruise ship.

Since the record of auxiliary cruisers converted from large cruise ships in Germany in the last plane was not very satisfactory, in Helena's view, converting high-speed cruise ships into auxiliary cruisers to break the war is definitely a way to use one's own shortcomings to attack others' strengths. practice.If you want to play a good battle at sea, the most important thing is high concealment. This is the biggest secret to the success of submarines and assault ships converted from ordinary merchant ships.

Now that the option of converting a high-speed cruise ship into an auxiliary cruiser has been ruled out, turning into an aircraft carrier seems to be the best destination for a high-speed cruise ship during the war.