Sonic boom characteristics of proposed supersonic and hypersonic airplanes

Sonic boom characteristics of proposed supersonic and hypersonic aircraf

Some Effects of Wing Planform on Sonic Boom

A wind-tunnel investigation was conducted to determine the effect of wing planform on sonic boom at Mach numbers of 1.7, 2.0, and 2.7. The results of the investigation show that the wing leading-edge sweep is one of the primary planform variables affecting the overpressure characteristics

Some effects of Mach number and geometry on sonic boom

Mach number and geometry effects on level of sonic boom overpressure and applicability of Whitham theory to calculation of sonic boo

Ground and Space-Based Measurement of Rocket Engine Burns in the Ionosphere

On-orbit firings of both liquid and solid rocket motors provide localized disturbances to the plasma in the upper atmosphere. Large amounts of energy are deposited to ionosphere in the form of expanding exhaust vapors which change the composition and flow velocity. Charge exchange between the neutral exhaust molecules and the background ions (mainly O+) yields energetic ion beams. The rapidly moving pickup ions excite plasma instabilities and yield optical emissions after dissociative recombination with ambient electrons. Line-of-sight techniques for remote measurements rocket burn effects include direct observation of plume optical emissions with ground and satellite cameras, and plume scatter with UHF and higher frequency radars. Long range detection with HF radars is possible if the burns occur in the dense part of the ionosphere. The exhaust vapors initiate plasma turbulence in the ionosphere that can scatter HF radar waves launched from ground transmitters. Solid rocket motors provide particulates that become charged in the ionosphere and may excite dusty plasma instabilities. Hypersonic exhaust flow impacting the ionospheric plasma launches a low-frequency, electromagnetic pulse that is detectable using satellites with electric field booms. If the exhaust cloud itself passes over a satellite, in situ detectors measure increased ion-acoustic wave turbulence, enhanced neutral and plasma densities, elevated ion temperatures, and magnetic field perturbations. All of these techniques can be used for long range observations of plumes in the ionosphere. To demonstrate such long range measurements, several experiments were conducted by the Naval Research Laboratory including the Charged Aerosol Release Experiment, the Shuttle Ionospheric Modification with Pulsed Localized Exhaust experiments, and the Shuttle Exhaust Ionospheric Turbulence Experiments

NACA Technical Notes

Report presenting three modifications to the leading-edge region of the NACA 64A010 airfoil section, which were designed and tested two-dimensionally at both low and high subsonic speeds. The modifications increased the low-speed maximum lift coefficient of the symmetrical reference section, largely by increasing the angle of attack at which stall occurred

Employee participation in environmental initiatives: Facilitating more environmentally conscious decision-making in innovation

In recent years society as a whole has become more aware and concerned about environmental issues. In light of increasingly stringent legislation and the more critical eyes of external stakeholders, companies have come to realise the heightened need for their actions to be seen as environmentally responsible. The innovation process provides companies with an excellent opportunity to influence the environmental impacts associated with their products. However, merely providing product developers with new processes and a toolbox of available ecodesign tools is rarely sufficient to facilitate more environmentally conscious decision-making in innovation. This paper proposes that employee participation within the development of new initiatives will aid the implementation of those initiatives. It highlights the first results from a study undertaken at Unilever seeking to initiate employee participation within initiatives for environmentally conscious innovation by ascertaining the attitudes of employees involved in the product innovation process regarding environmental responsibility and its integration into innovation