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In the expansion of composite material application, it is one of the most important subjects in assembly of aircraft structure how drilling of composite/metal stack should be processed in an efficient way. This paper will show the result of development of a drill bit for CFRP/Aluminum-alloy stack by Kawasaki Heavy Industries (KHI) and Sumitomo Electric Hardmetal (SEH). In order to improve workability and economic performance, the drill bit which enables drilling CFRP/Al-alloy stack: at 1 shot; from both directions; without air blow and coolant (just usual vacuuming); was required. A best mix drill bit which has smooth multi angles edge and pointed finishing edge was produced as a result of some trials. Developed drill bit achieved required performance and contributed to large cost reduction, labor hour saving, production speed increase and work environment improvement.

In the closed environments such as manned space station, it is necessary to remove contaminant gas to keep a suitable environment. Removal of gaseous contaminants generated from crew, animals, and plants is important function to keep the environment below the allowable level in the Closed Ecology Experiment Facilities (abbreviated as CEEF). CEEF consist of three modules for habitat, animal and plant, the supporting facilities for each module and a plant cultivation facility. CEEF are scheduled to be constructed from 1994 in Aomori Prefecture, northern part of Japan. For designing Trace Contaminant Control Assembly (TCCA) for CEEF, the following six (6) trace contaminants have been selected as major contaminant gas in CEEF; Ammonia (NH3) Methane (CH4) Ethylene (C2H4) Carbon Monoxide (CO) Nitrogen Dioxide (NO2) Sulfur Dioxide (SO2) Ethylene is well-known as an aggressive contaminant to plant growth and maturity.

“ASKA” is a STOL airplane with Upper Surface Blown type (USB) flaps used to perform research on powered lift technology developed by the National Aerospace Laboratory (NAL). ASKA has four high bypass ratio turbofan engines mounted above and forward of the wings, hydraulically actuated flight controls, and the Stability and Control Augmentation System (SCAS). The SCAS is a triple redundant system with three digital computers. In order to develop and evaluate its control laws, flight simulator tests have been conducted for 9 years during the design phase. Four flights have been devoted to evaluate functions of the SCAS and the control laws. The significant features of the control laws are to realize satisfactory flying qualities in the deep backside region at low airspeeds.

The traction-drive integrated drive generator (T-IDG®) has been developed since 1999 to replace current hydrostatic transmission drive generators mounted on Japanese military aircraft. The T-IDG® consists of a generator and a half-toroidal traction-drive continuously variable transmission (CVT), which maintains a constant output speed of 24000 rpm, that is, a 400 Hz AC power supply. To cope with recent trends of more electric aircraft (MEA) and the need for weight reduction, a high-speed traction-drive CVT is advantageous over other transmissions. The torque on the half-toroidal variator is transmitted through multiple power rollers. The equal load sharing among power rollers is typically controlled by a mechanical hydraulic feedback system, whose stability is one of the main issues for the high-speed traction-drive CVT. Previous studies have shown that insufficient damping and stiffness of the mechanical hydraulic feedback system cause self-induced vibration.

Electroimpact and Kawasaki Heavy Industries (KHI) have produced a new riveting process for the forming of Briles type rivets in Boeing 777 and 777X fuselage assemblies. The Briles rivet is typically used for fuselage assembly and is unique in that it has a self-sealing head. Unlike conventional headed rivets such as the NAS1079, this fastener does not require aircraft sealant under the head to be fluid tight. This unique fastener makes for a difficult fastening process due to the fact that interference must be maintained between the hole and fastener shank, as well as along the sides of the fastener head. Common issues with the formed fasteners include gapping under the fastener head and along the shank of the fastener. Electroimpact has employed a host of different technologies to combat these issues with Briles fastening. First, Electroimpact’s patented “Air Gap” system allows the machine to confirm that the head of the rivet is fully seated in the countersink prior to forming.

The feasibility study of the thermal control system for medium size or large size satellites was conducted to investigate the capabilities and specifications of devices such as cold plates, a radiator, a mechanical pump, and so on. In the first step of the system development demonstration, the cold plate was selected to investigate the performance among these devices. In this paper, the system concept of the advanced single-phase fluid loop and the evaluation by numerical analysis and experiments are described.