16,364 research outputs found

    Spin-tunnel investigation of a 1/13-scale model of the NASA AD-1 oblique-wing research aircraft

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    The spin and recovery characteristics of a 1/13-scale model of the NASA AD-1 oblique-wing research aircraft at wing-skew positions of 0, 25, 45, and 60 deg (right wing forward) were investigated. Spins were obtained for all wing-skew positions tested. For the unskewed wing position, two spin modes were possible. One spin mode was very steep and recoveries were obtained within 1 turn or less by rudder reversal. The second spin mode was flat and fast; the angle of attack was about 75 deg and the spin rate was about 145 deg/sec (2.5 seconds per turn). For the skewed wing positions, spins were obtained only in the direction of the forward-skewed wing (right wing forward). No spins were obtained to the left when the wing was skewed with the right wing forward. Recoveries should be attempted by deflecting the rudder to full against the spin, the ailerons to full with the spin, and movement of the wings to 0 deg skew. If the wing is skewed, the recovery may not be effected until the wing skew approaches 0 deg

    A method for determining the characteristic functions associated with the aeroelastic instabilities of helicopter rotors in forward flight

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    Computer program for determining characteristic functions of aeroelastic instabilities of helicopter rotor in forward fligh

    An evaluation of potential locations for AROD ground stations

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    Airborne Range and Orbit Determination tracking stations potential locations evaluation and accuracy during early minutes of fligh

    Spin-Tunnel Investigation of the Spinning Characteristics of Typical Single-Engine General Aviation Airplane Designs. 1. Low-Wing Model A: Effects of Tail Configurations

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    The effects of tail design on spin and recovery were investigated in a spin tunnel. A 1/11-scale model of a research airplane which represents a typical low-wing, single engine, light general aviation airplane was used. A tail design criterion for satisfactory spin recovery for light airplanes was evaluated. The effects of other geometric design features on the spin and recovery characteristics were also determined. Results indicate that the existing tail design criterion for light airplanes, which uses the tail damping power factor as a parameter, cannot be used to predict spin-recovery characteristics

    Spin-tunnel investigation of the spinning characteristics of typical single-engine general aviation airplane designs. 2: Low-wing model A; tail parachute diameter and canopy distance for emergency spin recovery

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    A spin tunnel study is reported on a scale model of a research airplane typical of low-wing, single-engine, light general aviation airplanes to determine the tail parachute diameter and canopy distance (riser length plus suspension-line length) required for energency spin recovery. Nine tail configurations were tested, resulting in a wide range of developed spin conditions, including steep spins and flat spins. The results indicate that the full-scale parachute diameter required for satisfactory recovery from the most critical conditions investigated is about 3.2 m and that the canopy distance, which was found to be critical for flat spins, should be between 4.6 and 6.1 m

    Generation and measurement of nonstationary random processes technical note no. 3

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    Generation and measurement of nonstationary stochastic processes related to Monte Carlo studies with analog compute

    An evaluation of the Department of Health’s Health and Social Care Volunteering Fund

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    The Health and Social Care Volunteering Fund (HSCVF) is an innovative programme that was established in 2009 by the Department of Health (DH) to build organisational and community capacity for volunteering through a national and local grant scheme. The HSCVF has offered both funds and tailored support to health and social care projects delivered by Voluntary, Community and Social Enterprise (VCSE) organisations. The HSCVF is managed by a partnership led by Ecorys and with expertise from leading national voluntary sector organisations: Attend, Community Service Volunteers (CSV) and Primetimers. To date the HSCVF has funded a total of 157 local and national projects, of which 114 are currently live. This report presents findings from an evaluation of the HSCVF with a specific focus on the 2010/2011 national and local projects, conducted by a team from the Institute for Health & Wellbeing at Leeds Metropolitan University. It presents evidence on the extent to which, how and in what ways the HSCVF programme has built organisational and community capacity across the national and local HSCVF projects, as well as on the health and social outcomes that resulted

    A low energy electron magnetometer

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    The concept of a highly sensitive magnetometer based on the deflection of low energy electron beams in magnetic fields is analyzed. Because of its extremely low mass and consequently high e/m ratio, a low energy electron is easily deflected in a magnetic field, thus providing a basis for very low field measurement. Calculations for a specific instrument design indicate that a low energy electron magnetometer (LEEM) can measure magnetic fields as low as 1000 nT. The anticipated performance of LEEM is compared with that of the existing high resolution magnetometers in selected applications. The fast response time of LEEM makes it especially attractive as a potential instrument for magnetic signature analysis in large engineering systems
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