HONDAJET STORY
THE JOURNEY TO A BREAKTHROUGH — ONE MILESTONE AT A TIME.
EXPLORE HONDAJET'S HISTORY OF INNOVATION.
SHARING INSIGHT INTO INNOVATION
Honda has published or presented* the following technical papers that shed light on the HondaJet and the advanced thinking that created it.
Flutter Characteristics of an Over-the-Wing Engine Mount Business-Jet Configuration
Michimasa Fujino and Hiroki Oyama
Mounting engines on the wing causes complex wing flutter characteristics. The location of the engine mass and the stiffness of the pylon relative to the wing are important in preventing hazardous wing flutter. In addition, if the nacelles are installed over the wing, aerodynamic interference between the wing and the nacelle may cause unfavorable flutter characteristics, in particular, at transonic speeds. The flutter characteristics of an over-the-wing engine mount configuration obtained from theoretical analyses and low speed and transonic wind tunnel tests are presented.
Wave-Drag Characteristics of an Over-the-Wing Engine Nacelle Business-Jet Configuration
Michimasa Fujino and Yuichi Kawamura
This paper presents the wave-drag characteristics of an over-the-wing nacelle configuration. The flow over the wing is accelerated such that the aerodynamic interference between the nacelle and the wing is critical in the transonic flight regime. In general, locating nacelles over the wing causes an unfavorable aerodynamic interference and induces a strong shock wave, which results in a lower drag-divergence Mach number. If the nacelle is located at the optimum position relative to the wing, however, the shock wave can be minimized, and drag divergence occurs at a Mach number higher than that for the clean-wing configuration. Theoretical analyses and experimental measurements demonstrate that a wave-drag reduction can be achieved by locating the nacelle front face near the shock-wave position on the wing.
Natural-Laminar Flow Airfoil Development for a Lightweight Business Jet
Michimasa Fujino, Yuichi Yoshizaki, Yuichi Kawamura
A 15% thick, natural-laminar-flow airfoil, the SHM-1, has been designed to satisfy requirements derived from the performance specifications for a lightweight business jet. The airfoil was tested in a low-speed wind tunnel to evaluate its low-speed performance. A fight test was also conducted to evaluate the performance of the airfoil at high Reynolds numbers and high Mach numbers. In addition, a transonic wind-tunnel test was conducted to determine the drag-divergence characteristics. The design requirements, methodology, and experimental verification are described.
Design and Development of the HondaJet
Michimasa Fujino
The HondaJet is an advanced, lightweight, business jet featuring an extra large cabin, high fuel efficiency, and high cruise speed compared to existing small business jets. To achieve the high-performance goals, an over-the-wing engine-mount configuration, a natural-laminar-flow wing, and a natural-laminar-flow fuselage nose were developed through extensive analyses and wind-tunnel tests. The wing is metal, having an integral, machined skin to achieve the smooth upper surface required for natural laminar flow. The fuselage is constructed entirely of composites; the stiffened panels and the Sandwich panels are co-cured integrally in an autoclave to reduce weight and cost. The prototype aircraft has been designed and fabricated. Major ground tests such as structural proof tests, control-system proof test, system function tests, and ground-vibration tests have been completed. The first flight was conducted on 3 December 2003, and flight testing is currently underway. The aerodynamic, aeroelastic, structural, and systems designs and tests conducted during the development are described.