Early the next morning, Li Yunxiang came over to wake up Bai Zhizhan, and then took Bai Zhizhan to the airport.

When he saw those huge heavy bombers, Bai Zhizhan didn't react at first, until he came to the bombers and really felt its enormity, and he suddenly realized that this was the largest aircraft he had ever seen, at least in terms of wingspan and length.

Although there were only four engines, it was significantly larger than the previous four-engine bombers.

"Is this the 'Condor'?"

After Bai Zhizhan raised a question, Li Yunxiang just nodded and didn't explain much.

That's right, this is the "Heavy Bomb-5" bomber, nicknamed the "Condor", and the third 4-engine heavy bomber obtained by the Imperial Army Aviation during the Great War.

For this kind of bomber, Bai Zhizhan knows not a lot.

The development of the "Divine Condor" had begun before the outbreak of the Great War, and He Pengfei's company had invested in it and assumed all the risks of development.

At that time, among the people who instigated He Pengfei to spend money to develop the "Divine Condor", there was Bai Zhizhan!

In order to win the favor of the army and get orders for mass production, it is also to attract attention, and the performance indicators of the "Condor" at the time of the project were set extremely outrageous. For example, the bomb load must reach at least 9 tons, the combat radius must be at least 3,000 kilometers, the maximum flight altitude must exceed 10,000 meters, the flight speed must exceed 500 kilometers per hour, and several 20-mm machine guns must be equipped, and armor must be laid in key parts such as the cockpit.

Such an advanced bomber, not to mention at that time, even now, may not be able to be built.

First of all, we have to solve the problem of the engine.

In fact, in the early stages of development, or conceptual design, the number one problem is the lack of a suitable engine.

In previous versions of the design, all of them used 6 engines!

The reason is the same, even if the 2000 horsepower air-cooled engine that is still in the development stage and does not know when it will be mass-produced, it will also need 6 units to make the "Condor" reach the main design indicators. If only four engines are used, the load must be reduced or the range shortened.

Before the outbreak of the Great War, the Army Aviation would certainly not be able to accept a bomber with 6 engines.

In fact, even after the outbreak of the Great War, the Army Aviation was not very interested in 6-round bombers.

While in theory, six engines would provide greater safety redundancy, it would also mean greater complexity and lower bomber completion.

In addition, the purchase price and the cost of equipment maintenance must be considered.

A 6-engine heavy bomber costs at least 40% more than a 4-engine bomber, but in general, the combat efficiency is about the same as that of a 4-engine bomber.

Crucially, less than 10% of ultra-long-range bombing missions are beyond the reach of a four-bomber.

All in all, the effectiveness of a 6-engine bomber is too low.

Even if there is no question of funding in wartime, the overall cost must be taken into account.

Excessive manufacturing costs, or maintenance and usage costs, mean that mass production is not possible.

It is precisely in this way that after the outbreak of the Great War, after the "Condor" received investment from the military, its main design direction was also determined.

With only 4 engines, it is necessary to ensure a combat radius of 3,000 kilometers first, and a normal bomb load of at least 6 tons secondly.

As for other performance indicators, they are all negotiable.

Even at this point, the key is the engine.

When the main line energy indicators are determined, the best air-cooled engine that can be obtained is only 2000 horsepower, and the output is still pitiful, and it is necessary to give priority to the carrier-based aircraft of the Navy. The key point is that this star-shaped air-cooled engine specially developed for carrier-based aircraft is not strong enough, and there is also a fatal defect that the output power decays rapidly with the increase of altitude, which cannot meet the fatal defect of the bomber's long-term high-altitude flight.

At that time, it was actually an old engine with 1800 horsepower.

Obviously, if only a 1800-horsepower engine is used, then the "Condor" will not be able to obtain a combat radius of 6 km with a bomb load of 3000 tons anyway.

Even if the all-aluminum structure is adopted, the comprehensive performance is slightly better than the previous heavy bomber, the heavy bomber-4 nicknamed "Pegasus", and there will be no essential improvement. Because the cost will definitely not come down, it is certainly impossible to replace the "Pegasus", and the chances of obtaining mass production are very slim.

Do not forget that electrolytic aluminum is not cheap, and bombers with aluminum structures must be extremely expensive.

It is precisely because of this that in the more than a year after the outbreak of the Great War, that is, about a year after receiving military funding and officially becoming a military equipment project, the "Condor" was in the conceptual development stage, mainly waiting for the engine and finding ways to reduce production costs.

There are several design versions that even replace aluminum with wood!

Judging from the aircraft made of wood in the Royal Air Force, the main performance is not too bad while greatly reducing the cost.

As for high-quality timber, it was not a problem at all for a vast empire.

If nothing else, the far north of the empire is almost entirely primeval forest.

Of course, to cure the root cause, you still have to work on the engine.

Until now, the Empire's large air-cooled engines have not entered mass production.

According to the plan, the 2400-horsepower twin-supercharged air-cooled engine specially developed for the "Condor" will not be put into mass production until the fourth quarter of the new calendar 103.

Fortunately, the problem with the engine found a replacement in the Hindman Empire.

The Empire had an engine with a maximum power of nearly 3,000 horsepower, the DB610 series engines used in the He-177 twin-engine bomber.

This combination supercharged liquid-cooled engine has a lot of problems, such as very poor reliability.

Due to this limitation, the production of He-177 has not been very high, and the range of use has been severely limited.

However, there was no better choice for the Imperial Army Airlines.

When this engine was introduced, at the request of the military, the manufacturer responsible for the production task made some adjustments, mainly to remove the second-stage supercharging system, so as to improve the stability of the engine. The price paid for this was that the engine's output was directly reduced to 2,200 horsepower, and the high-altitude performance was very poor, which limited the practical ceiling of the heavy bomber with this engine.

It's just that the difference of 200 horsepower, as well as the significant reduction in high-altitude performance, is actually not a problem.

At least, this is a high-horsepower engine that can be obtained immediately, and for the time being, only the "Condor" can match.

The key is that it is the small manufacturers that undertake the production.

Because the application range of large water-cooled engines is very narrow, when deciding to introduce licenses, large domestic engine factories refused the invitation to cooperate on the grounds of saturation of production capacity, and finally the military could only come forward and organize several small manufacturers together for joint production.

To this end, the military also specially dispatched experts to provide technical support to manufacturers.

The advantage is that there is no problem of having to compete with other engines for the production line.

It is precisely in this way that in June, the "Condor" was approved by the Army Aviation and officially entered the mass production stage, and the first batch of orders was 500 aircraft.

In order to ensure the speed of production, the first batch of 500 aircraft was not prepared for future modifications.

If additional orders were required, the engine anchors of the wings would have to be adjusted from the 501st to allow for the replacement of 2,400 hp air-cooled engines in the future.

Now, 20 have been delivered, all in Sri Lanka.