Vertical take-off and landing aircraft is a rookie in the fighter family. This concept of aircraft was first born in the 1960s. At that time, due to the height of the Cold War, both East and West were worried about how fighter planes would take off once their airports were blown up by each other. Since then, various types of VTOL aircraft have come out one after another.
China is obviously a "latecomer" in the field of VTOL aircraft, but a brand-new patent recently applied by Cheng Fei may prove that we have achieved "straight overtaking" in VTOL technology.
The reason why VTOL aircraft appears is that once the airport is attacked by the enemy, ordinary fighters can't take off normally, so VTOL aircraft can continue to perform various air combat missions to ensure that our army is not threatened by the enemy air force. By June 2023, there are three mature vertical takeoff and landing schemes abroad:
The first one is a single hairstyle design represented by the British Harrier fighter. The British Harrier is only equipped with a Pegasus MK 104 engine, but this engine has four nozzles, which can rotate 90.
When taking off vertically, the four nozzles of the engine rotate downward, so that when the engine is running, the jet flow can generate upward reaction force, thus "lifting" the aircraft. When it rises to a safe height, the four nozzles rotate again to inject air, making the plane fly forward like a common jet fighter.
However, the design of "Pegasus MK- 104" engine is too complicated, which leads to the unfriendly operation performance of "Harrier" fighter. If you are not careful, the plane will be destroyed and people will die. A typical example is the AV-8B Harrier II fighter developed after the introduction of Harrier II fighter in the United States. More than 360 fighter planes were built, but half of them crashed due to improper operation, and the accident rate was as high as 3 1.44 per 65438+ million hours.
And interestingly, because of the unique design of AV-8B, once the plane crashes, pilots can hardly escape, and most of them crash and people die, so they are called "widow makers".
The second is the three-engine design represented by Jacques -38 and Jacques-14 1 in the former Soviet Union. Jacques -38 and Jacques-14 1 are equipped with three engines. Take Jacques-14 1 as an example. The aircraft is equipped with 1 Tumanski R-79 engine and two kerimov RD-4 1 engines, in which R-79 has a vectoring nozzle that can rotate 90 degrees and can be used for propulsion and vertical takeoff, and RD-4 1 is installed in the upper and lower structures.
The advantage of this design is that the three engines perform their respective duties, which is much better than the Harrier fighter in safety. However, this design also has its own defects, that is, after the plane changes to level flight, two RD-4 1 engines specially used for take-off and landing will turn off and become "dead weight", which undoubtedly takes up the payload of the plane greatly, leading to Jacques -65438.
The third design, which is also the most mature at present, is the structure of vector engine+lift fan adopted by American F-35B fighter. Aiming at the design defects of Jacques-14 1, the F-35B removed the special lift engine at the front of the aircraft and installed a large lift fan instead. At the same time, the fan is connected with the main engine through the transmission shaft, so that when the main engine is started, the lifting fan can be driven to rotate through the transmission shaft to spray gas downwards, thereby lifting the aircraft into the air.
The lift fan of this design discharges cold air, which will not scorch the fuselage and the ground below the fuselage, thus reducing the ablation of the aircraft. At the same time, the weight of the lift fan is obviously less than that of the engine, thus reducing the "dead weight" carried by the aircraft in normal flight and making the F-35B have satisfactory load and range.
However, the above three design ideas can be said to be western inventions (after all, Russia is also a European country in theory), and the engine patent design that Cheng Fei applied for in China this time is completely different from the western ideas, which, in the words of our ancestors, is "to find another way".
According to the patent content, Cheng Fei adopted a unique series of engine design, that is, two turbofan engines were "connected" together to form a lift system. Among them, the former engine takes air from the rear of the aircraft, and the exhaust ports are designed on both sides of the aircraft fuselage, which can play a balancing role.
The latter engine adopts vector nozzle design. Under normal circumstances, it takes air from the air inlets on both sides of the aircraft nose, and then the tail nozzle can rotate 90. When the tail nozzle is lowered and the two engines are started at the same time, the plane can take off under the action of the two engines. When the plane rises to a safe height, the engine exhaust port and tail nozzle on both sides of the fuselage rotate backwards at the same time, so that the plane can fly normally like a normal fighter.
The biggest feature of Cheng Fei's design scheme is that the lift engine that becomes "dead weight" when flying flat on Jacques-14 1 can be used even in normal flight, because the nozzles of the front engine are on both sides of the fuselage and can rotate 90 degrees, so that when the plane flies flat, the front engine does not need to be turned off and can continue to work, providing additional thrust for the aircraft.
The design of the rear fuselage is roughly the same as that of the F-35B, and it can be freely switched between take-off and landing and normal flight through the steering of the main engine nozzle.
Although Cheng Fei's design has not yet come up with a specific aircraft model, it looks like a J-10 fighter with a deep change from the scheme announced by Cheng Fei. The improved model adopts a pneumatic scheme similar to J-10, which adopts air intake under the belly, but cancels the canard and changes the single vertical tail into a V-shaped double vertical tail.
Considering that we have now equipped three Type 075 amphibious assault ship, the only difference compared with the US military is the lack of fixed-wing VTOL aircraft, so the comprehensive operational effectiveness of Type 075 is worse than that of American counterparts. The exposure of Cheng Fei's VTOL patent now means that we have our own independent VTOL plan, and it may not be long before we can see the domestic "Rabbit F-35B" fighter on the 075 amphibious assault ship.