For aerial spray application, there is some question if off-target drift (both near and far) is influenced by which boom is spraying and the direction of propeller wash rotation. This information may be useful when switching off one boom close to a field boundary. The effect of alternate boom switching and propeller wash direction on aerial spray drift from a turbine-powered aircraft was invest...

In propeller driven aircraft the main source for internal noise are almost tonal disturbances caused by the propeller blades that are passing the fuselage. In a certain four propeller military transport aircraft the maximum sound level in the cabin can reach up to 110 dB(A), not taking into account any noise control treatments. Inside the semi closed loadmaster working station (LMWS) the sound ...

Current trends in the design of helicopter have shown that in order to be economically viable and competitive it is necessary to investigate new design concept which may give an improvement in performance and operational flexibility goal and expanding the flight envelope of rotorcraft, but must be shown to be costeffective. The helicopter has carved a niche for itself as an efficient vertical t...

NASA’s research into distributed electric propulsion (DEP) includes the design and development of the X-57 Maxwell aircraft. This aircraft has two distinct types of DEP: wingtip propellers and high-lift propellers. This paper focuses on the unique opportunities and challenges that the high-lift propellers—i.e., the small diameter propellers distributed upstream of the wing leading edge to augme...

A novel approach to passive propeller blade pitch variation is investigated. To effect passive pitch changes, the propeller blades are allowed to pivot freely about a radial axis, and aerodynamic pitchingmoments are tailored to give favorablebladepitch angles over awide range of advance ratios.Computationalmodelingof the system indicated that a large expansion of the efficient operating envelop...

The multifractal characteristics of return signals from aircraft targets in conventional radars offer a fine description of dynamic characteristics which induce the targets’ echo structure; therefore they can provide a new way for aircraft target classification and recognition with low-resolution surveillance radars. On basis of introducing the mathematical model of return signals from aircraft...

1 1 ABSTRACT The success or effectiveness for any aircraft design is a function of many trade-offs. Over the last 100 years of aircraft design these trade-offs have been optimized and dominant aircraft design philosophies have emerged. Pilotless aircraft (or uninhabited airborne systems, UAS) present new challenges in the optimization of their configuration. Recent developments in battery and m...

This paper investigates the precision and capability of low cost off-line industrial photogrammetry for determination of deformations in aircraft parts. The study concentrates on deformation analysis of an airplane propeller through standard photogrammetric procedures. In this regard, around 100 targets were fixed on the blades of the propeller and imaged from several stations. The left and rig...

The widespread development of unmanned aerial vehicles and light propeller-driven aircraft poses the task reducing community noise such vehicles. To solve this problem, tools are needed to calculate devices. paper presents results numerical simulation an AV-2 propeller mounted on AN-2 aircraft. authors use acoustic-vortex method problem aeroacoustic modeling in presence incoming flow. shows a g...