The aerial relay system: An energy-efficient solution to the airport congestion problem

The ability to transfer airline passengers between aircraft in flight, if adequately developed and integrated into the national air transportation system, could provide significant improvements in transportation-system performance, in terms of airport congestion, fuel consumption, and passenger service. The proposed Aerial Relay System concept, which was developed as a means of exploiting inflight transfer, makes use of large 'cruise liner' aircraft which fly continuously along their routes, docking periodically with short-haul feeder aircraft for exchange of payloads. Preliminary vehicle designs for a representative system are described and the operational feasibility of the concept for the United States in the 1990's is discussed

Pressurized structures of high mobility

Filamentary fabric made with slip-net principle principle for pressurized suit

The effect of atmospheric drag on the design of solar-cell power systems for low Earth orbit

The feasibility of reducing the atmospheric drag of low orbit solar powered satellites by operating the solar-cell array in a minimum-drag attitude, rather than in the conventional Sun pointing attitude was determined. The weights of the solar array, the energy storage batteries, and the fuel required to overcome the drag of the solar array for a range of design life times in orbit were considered. The drag of the array was estimated by free molecule flow theory, and the system weights were calculated from unit weight estimates for 1990 technology. The trailing, minimum drag system was found to require 80% more solar array area, and 30% more battery capacity, the system weights for reasonable life times were dominated by the thruster fuel requirements

Deployment mechanics for an inflatable tension-cone decelerator

Experimental design of deployable tension cone decelerator with inflatable toroids for compression resistant structures in base of con

The rotornet- a high-performance hypersonic decelerator for planetary entry

Rotating net decelerator for hypersonic reentr

Making and suspension capabilities of vibratory agitators in a slab tank

Seven different vibratory agitators, consisting of single and dual flat blade configurations or dual angle blade configurations, were studied for their ability to produce mixing and solid suspension in a slab tank. The mixing behavior of the various configurations was recorded on video tape, and mixing times were measured as the time needed to disperse injected dye. The solid suspension tests, using ash tray sand, were conducted to determine the minimum stroke frequency of the agitators needed for complete off-bottom suspension. The mixing studies demonstrated that vibratory agitation produced strong vertical fluid motion, good bulk circulation and dispersion in the liquid. The effects of stroke frequency, n; amplitude, a; blade width, w; blade clearance, c; and liquid depth, h, on mixing time, {theta}, were studied. Single blade geometries produced complete mixing in the least number of strokes. The most effective geometry, in terms of both mixing and solid suspension, was a single flat blade with minimum off-bottom clearance and a blade width/tank thickness ratio, w/T, of 0.74 at the maximum stroke amplitude of 51 mm

Role of hydrodynamic factors in controlling the formation and location of unconformity-related uranium deposits: insights from reactive-flow modeling

The role of hydrodynamic factors in controlling the formation and location of unconformity-related uranium (URU) deposits in sedimentary basins during tectonically quiet periods is investigated. A number of reactive-flow modeling experiments at the deposit scale were carried out by assigning different dip angles and directions to a fault and various permeabilities to hydrostratigraphic units). The results show that the fault dip angle and direction, and permeability of the hydrostratigraphic units govern the convection pattern, temperature distribution, and uranium mineralization. Avertical fault results in uranium mineralization at the bottom of the fault within the basement, while a dipping fault leads to precipitation of uraninite below the unconformity either away from or along the plane of the fault, depending on the fault permeability. A more permeable fault causes uraninite precipitates along the fault plane,whereas a less permeable one gives rise to the precipitation of uraninite away from it. No economic ore mineralization can form when either very low or very high permeabilities are assigned to the sandstone or basement suggesting that these units seem to have an optimal window of permeability for the formation of uranium deposits. Physicochemical parameters also exert an additional control in both the location and grade of URU deposits. These results indicate that the difference in size and grade of different URU deposits may result from variation in fluid flow pattern and physicochemical conditions, caused by the change in structural features and hydraulic properties of the stratigraphic units involved