HA-420 HondaJet

In December 2003, the Japanese automotive company Honda unveiled its first aircraft, the HA-420 HondaJet (first flight – 03.12.2003), intended for serial production and sales. This was the first aircraft in Japan entirely manufactured by a single company (including engines) without any government support.

For the aircraft, Honda developed the HF118 turbofan engine and tested it for a year, installing it on the left pylon of a Citation Jet. The HondaJet’s engines are mounted on pylons ABOVE the wing, similar to the German VFW-614. This configuration helps reduce downward noise (ground noise, especially during takeoff and landing).

Additionally, it improves airflow over the wing’s upper surface and reduces the likelihood of foreign object ingestion from the runway. However, the airflow structure becomes more complex, necessitating intensive wind tunnel experiments. Engine operational stability with this configuration was verified for angles of attack up to 26°. Fuel is stored in two wing caisson tanks, a collector tank, and a tank in the rear fuselage. The refueling system is centralized.

Innovative Design and Aerodynamic Testing

A special laminar wing profile, SHM-1, was also developed. A wing section with this profile was tested on a T-33 flying laboratory. For this, the desired profile was formed directly onto the T-33’s skin using polyurethane foam and covered with fiberglass. Under the new skin, 119 pressure sensors were installed. The transition from laminar to turbulent flow was detected by an infrared camera mounted on the T-33’s cockpit (air heats slightly in turbulent flow).

Flaps, deflecting 15.7° for takeoff and 50° for landing, are installed over 30% of the wingspan. The wing and empennage are aluminum. The empennage is T-shaped. The fuselage is made of carbon-composite materials with aluminum reinforcing elements, and the nose section is smoothed for laminar flow. The company claims that this reduces fuselage drag by 10% compared to conventional fuselages of the same size.

The cabin length is 4.6m, and its height is only 1.5m. The cabin is pressurized; at an altitude of 13km, pressure equivalent to 2.4km above sea level (standard atmosphere) is maintained (maximum pressurization – 0.61 atm). The anti-icing system on the wing’s leading edge is fed by warm air from the engines. The cockpit windows are electrically heated. However, there is no information about anti-icing protection for the empennage and air intakes.

The landing gear is tricycle, hydraulically retractable. The nose gear has an electro-remote control system and deflects 50° left and right for taxiing and 10° for takeoff roll. During static tests, the fuselage and wing were loaded only up to 80% of design loads, with 100% load behavior simulated by computers. As a result, the airframe that underwent static tests was used for building the flight prototype. Only the empennage was tested under full load.

Production and Evolution

Honda planned to sell the HondaJet in the USA as a light, inexpensive business jet. Honda intended to complete the construction of its aircraft manufacturing plant by early 2011. The first aircraft were to be delivered to customers in the third quarter of 2012. The HondaJet’s cost would be $4.5 million.

In 2018, Honda Aircraft Company began supplying a new version of its aircraft – the HA-420 HondaJet Elite. The new model was presented in May of that year at the EBACE exhibition in Geneva, Switzerland.

According to Flying magazine, the updated model received a greater flight range, approximately 2661 kilometers, as well as an improved Garmin G3000-based instrument panel; among other things, the Elite version is available in new color options.

Technical Specifications

Image and diagram gallery of the HA-420 HondaJet