Search Results

The authors worked in the Engine Department at Nakajima Aircraft Co. from 1936 to 1945. Nakagawa was in the Engine Design Department, where he was involved in designing the air-cooled, radial double-row 14-cylinder 1,100 hp Sakae Model 20 engine and the radial 18-cylinder 1,800 - 2,000 hp Homare engine. Mizutani was a field engineer for these two engines and other engines. During that period we gained much experience in fuel and lubrication systems. Before the authors joined Nakajima, the company's engine development team had already developed a carburetor-based fueling system, which was subsequently used in all Nakajima engines. From 1941 on, all newly designed engines had to use 87-92 motor octane fuel by order of the Army and Navy. It was a very difficult task to change the engine specifications to meet this requirement, particularly for the Homare engine, which was initially designed for 100-octane fuel. The authors explain various steps taken to overcome this difficulty.

Unlike the conventional bleed-air method, using electro-thermal anti-/de-icing methods to completely evaporate all of the supercooled water droplets that collide with the leading edge wing surface of aircraft flying in a freezing environment is not easy in terms of technical feasibility and energy efficiency[1]. If the leading edge is warm enough to stay free from frozen water droplets, the water moves backward while still maintaining the liquid phase. The droplets may freeze somewhere on an unheated surface after being halted for some reason and stick on the surface. Ice gradually accumulates as this process is repeated. Therefore, liquid water must be removed from the surface as soon as possible if the electrothermal method is employed for icing prevention. One answer to this problem is coating the surface with a superhydrophobic paint.

Adhesively bonded structures, that is, metal to metal bonding of cabin and wing skin and honeycomb sandwich panel of pressure bulkhead, are used in newly developed general aviation pressurized piston twin aircraft, Rockwell/Fuji Model 700. This paper presents the design consideration of each bonded structure showing the advantages of bonding, and its quality control procedure used in subject aircraft.

New icephobic paint has been developed for the purpose of preventing the icing of the airfoils of aircrafts. The basic characteristics of the paint in terms of icing prevention were examined by an optical method and a load test. The water contact angle is so high-150 degrees-that high water repellency can be obtained as expected from the design. The adhesion strength of the ice formed on this coating is decreased to the lowest value as compared to all paints ever developed. The results from the icing wind tunnel test carried out in conditions similar to what aircrafts encounter show that the paint contributes to fuel and weight savings due to the effective use of deicer.