A series of flight tests were conducted to design and evaluate a Combined Vision System (CVS) that integrates a forward looking infrared video image with synthetic vision on a primary flight display. System features included colorizing the video image to mesh with the synthetic terrain background, decluttering the approach symbology to facilitate the detection of the approach lights and runway markings, creating a semi-transparent IR sky to ensure continuous situational awareness of the surrounding terrain, and annunciating the decision height to facilitate the transition to the actual runway environment. Over 100 approaches were flown during three flight test sessions. For the first flight test session pilots reviewed early CVS proofs of concept on Honeywell's Citation Sovereign.
Abstract Carbon fiber reinforced plastic (CFRP) has been used in automobiles as well as airplanes. Because of its light weight and high strength, CFRP is a good choice for making vehicle bodies lighter, which would improve fuel economy. Conventional metal bodies provide a convenient body return for electric wiring and offer good shielding against electromagnetic fields. Although CFRP is a conductor, its conductivity is much lower than that of metals. Therefore, CFRP bodies are usually not useful for electric wiring. In thunderstorms, an automotive body is considered to be a Faraday cage that protects the vehicle’s occupants from the potential harms of lightning. Before CFRP becomes widely applied to automotive bodies, its electric and electromagnetic properties need to be investigated in order to determine whether it also works as a Faraday cage against lightning. In this article, CFRP and metal body vehicles were tested under artificial lightning.
Abstract Joining titanium (Ti) alloys with conventional processes is difficult due to their complex structural properties and ability of phase transformation. Concerning all the difficulties, diffusion bonding is considered as an appropriate process for joining Ti alloys. Ti6Al4V, which is an α+β alloy widely used for aero engine component manufacturing, is diffusion bonded in this investigation. The diffusion bonding process parameters such as bonding temperature, bonding pressure, and holding time were optimized to achieve desired bonding characteristics such as shear strength, bonding strength, bonding ratio, and thickness ratio using response surface methodology (RSM). Empirical relationships were developed for the prediction of the bond characteristics, and sensitivity analysis was performed to determine the increment and decrement tendency of the shear strength with respect to the bonding parameters.
Abstract A key problem of the construction of fully electric aircraft is the limited energy density of battery packs. It is generally accepted that this can only be overcome via new, denser battery chemistry together with a further increase in the efficiency of power utilization. One appealing approach for achieving the latter is using laser-assisted filler-based joining technologies, which offers unprecedented flexibility for achieving battery cell connections with the least possible electrical loss. This contribution presents our results on the effect of various experimental and process parameters on the electrical and mechanical properties of the laser-formed bond.
Abstract Electric heavy-duty tractor-trailers (EHDTT) offer an important option to reduce greenhouse gases (GHG) for the transportation sector. However, to increase the range of the EHDTT, this effort investigates critical vehicle design features that demonstrate a gain in overall freight efficiency of the vehicle. Specifically, factors affecting aerodynamics, rolling resistance, and gross vehicle weight are essential to arrive at practical input parameters for a comprehensive numerical model of the EHDTT, developed by the authors in a subsequent paper. For example, drag reduction devices like skirts, deturbulators, vortex generators, covers, and other commercially available apparatuses result in an aggregated coefficient of drag of 0.367. Furthermore, a mixed utilization of single-wide tires and dual tires allows for an optimized trade-off between low rolling resistance tires, traction, and durability.
This specification covers a titanium alloy in the form of bars and forgings 11.0 inches (279.4 mm) and under in nominal cross-sectional thickness diameter and of forging stock.
This specification covers an aluminum alloy in the form of bars and rods 0.500 inch (12.50 mm) and over in nominal diameter or least difference between parallel sides.
This specification covers an aluminum alloy in the form of bars and rods 0.500 in. (12.50 mm) and over in nominal diameter or least distance between parallel sides.
This specification covers an aluminum alloy in the form of bars and rods 0.500 inch (12.7 mm) to 8.000 inches (203.2 mm) in nominal diameter or least difference between parallel sides and up to 50 square inches (322.6 square centimeters) in cross-sectional area (see 8.7).