[YesAuto Wonderful Car Life] HA-420, you may think it is a new car that you have never heard of, but it is actually an airplane. At the Asian Business Aviation Conference and Exhibition (ABACE), which opened on April 11, Honda brought their first product in the aviation field.
If you have to write real shots of the aircraft on the car website, then I think it is more appropriate to start with this aircraft, after all, it comes from the Honda Aircraft Company (Honda Aircraft Company), which is a subsidiary of Honda Motor.
In fact, Honda was originally a group involved in many fields, from automobiles and motorcycles to various power plants and even robots. Moreover, Mr. Soichiro was also a flying enthusiast, but it was a pity that he did not realize his small desire to build airplanes in his lifetime.
The origin of Honda aircraft can be traced back to 1986, when the company secretly began aviation research. In 1993, the first HA20 prototype was successfully developed. This aircraft was only a test product and was not put into production.
In 1997, Honda Aircraft Project Chief Engineer and later Honda Aircraft Company CEO Mr. Fujino Doug proposed the OTWEM layout (Over-the-Wing-Engine-Mount) for the first time, placing two engines on the main wing, which became the original prototype of HondaJet. .
In 2003, the first HondaJet prototype successfully flew for the first time, followed by a long test flight process, until it was certified by the Federal Aviation Administration (FAA) in 2015. According to the terms of our automotive industry, HondaJet is officially listed! Become a new competitor in the business jet market.
From the perspective of level, this aircraft has a length of 12.99 meters and a wingspan of 12.12 meters. It belongs to the standard light or entry-level business jet category. It belongs to the same level as the Cessna Citation M2 and Embraer Phihong 100. .
In terms of appearance, the biggest feature of this aircraft is its unique engine layout. The engines of traditional light aircraft are installed on the tail, while the two HondaJet engines are connected to the main wing and placed above the rear of the wing.
Strictly speaking, this is not Honda’s first. There have been some similar designs in history. The most similar is the VFW-614, but limited to the technological level at the time, the efficiency of the aircraft was greatly affected. In the end, the output of this aircraft was very high. Small and not popular.
Now HondaJet has carried forward this layout again. Its advantage is first to reduce the wing pressure, because most of the weight of the aircraft after take-off will be concentrated on the wing roots, and more structural strengthening of the wing is needed to increase the weight, and placing the engine on the wing is equivalent to reducing the body. Weight, so there is no need for so much structural reinforcement.
Another benefit is to save space. The traditional engine tail crane layout will take up the rear space of the fuselage, while the HondaJet saves the space behind the cabin, making the fuselage more spacious.
There is also a reduction in resistance. Theoretically speaking, the upper airflow velocity of the wing is faster, and it will approach the speed of sound earlier when flying at high speeds, resulting in a sharp increase in drag, which is not suitable for arranging the nacelle. However, the position of the nacelle of the HondaJet has been accurately calculated, which not only improves the lift coefficient , Can also minimize high-speed flight resistance and improve economy.
In addition, this design also helps reduce noise. The engine nacelle of the traditional tail crane layout is directly connected to the fuselage, which will transmit more vibration, while the engine arranged on the wing is farther away from the nacelle, so the vibration is smaller.
However, this styling also brings many problems to the aircraft design. In order to minimize the impact on the wing, it can be seen that HondaJet has arranged the engine nacelle at the rear of the wing, so as to keep the wing “clean” as much as possible and obtain sufficient lift. In addition, the engine is also installed relatively high to avoid the low pressure area to avoid affecting the engine's air intake.
In this way, we will find that the entire engine compartment will be arranged relatively high, and a lot of design analysis will be required in terms of strength, force and resistance, which will increase the difficulty of manufacturing. In addition, this style is not acceptable to all consumers from an aesthetic point of view.
After talking about the OTWEM layout, let's take a look at other aspects of this aircraft. Like cars, weight reduction is the mainstream trend in the aviation industry. This aircraft is no exception. Some hatch covers on the fuselage are made of carbon fiber, but the main structures such as the body and wings are still traditional aluminum alloys.
The shape of the nose is aerodynamically modified to minimize resistance. The jagged edge of the cockpit windshield is very similar to the cabin cover of a stealth fighter, in fact it is a heating deicing device.
The wing is a traditional lower single wing design, using the new SHM-1 laminar airfoil developed by Honda, the purpose is also to reduce drag.
The function of the wing knife is to inhibit the flow of the attached layer to the outside and improve the controllability at high angles of attack. In our impression, this device often appears on old-fashioned Soviet-made fighter jets. Today's fighters and large passenger aircraft use leading edge slats to suppress the separation of the boundary layer, but for this kind of small aircraft, the wing knife is the simplest and most practical method.
Wingtip winglets are a very common design at present, and their function is to suppress eddy currents, reduce induced drag, and improve efficiency.
HondaJet is equipped with the HF120 turbofan engine developed in cooperation with General Electric. This engine has a dual-rotor structure, a fan diameter of 1.1 meters, a two-stage low-pressure compressor + a single-stage centrifugal high-pressure compressor, a bypass ratio of 2.9, and a maximum thrust of 2095 pounds, which is about 950 kg.
Enter the aircraft and look at the cockpit first. HondaJet is equipped with Garmin G3000 full LCD avionics system. This system has three 14.1-inch color multi-function displays, and for the first time uses touch screen operation, omitting a large number of traditional buttons on previous aircraft, and achieving a high level of automation. Convenient operation.
The ergonomic design of the cockpit is also very hard. It obviously draws on the elements of the car, and the interface is friendly and warm. For example, the engine start button is very similar to the car. It makes the tedious operation easy and creative.
The cabin has a 4+1 seat layout: 4 standard passenger seats + 1 flight attendant seat. The four passengers have a space of 3.69 meters long, 1.52 meters wide and 1.45 meters high.
It is worth mentioning that there is a fully functional toilet at the rear of the cabin, which improves comfort.
Thanks to the engine layout, the nose and tail of this aircraft also have a total of 1868.9 liters of storage space, which is outstanding.
In terms of performance, HondaJet has a maximum cruising speed of 778 km/h and a maximum ceiling of 13,100 meters, which has a strong advantage in the same class. Under NBAA IFR backup fuel conditions, the maximum range is 1,223 nautical miles (about 2,265 kilometers).
HondaJet is an impressive product, and the OTWEM layout is undoubtedly a useful innovation for small jets.In fact, the aircraft itself is a product of mutual compromise between various needs. HondaJet is not perfect, but it does provide a unique idea for the development of the aircraft, and its performance has reached an eye-catching level.
In addition, we also see some concepts from the automotive field from this aircraft, such as practical interior design and maximized space utilization. It can be seen that there are still many similarities between cars and aircraft. The aircraft is priced at US$4.5 million in the United States and will soon enter the Chinese market.