Improving Feasibility of Point to Point Operations Through Civil Aerial Refuelling

Re-imagining of the aerial transportation system has become increasingly important as the need for significant environmental and economic efficiency gains has become ever more prevalent. A number of studies have highlighted the benefits of the adoption of air to air refuelling within civil aviation. However, it also opens up the potential for increased flexibility in operations through smaller aircraft, shifting emphasis away from the traditional hub and spoke method of operation towards the more flexible Point to Point operations. It is proposed here that one technology can act as an enabler for the other, realising benefits that neither can realise as a standalone. The impact of an air-toair refuelling enabled point to point system is discussed, and the affect on economic and environmental cost metrics relative to traditional operations evaluated. An idealised airport configuration study shows the difference in fuel burn for point to point networks to vary from -23% to 28% from that of Hub and Spoke depending on the configuration. The sensitive natures of the concepts are further explored in a second study based on real airport configurations. The complex effect of the choice of a Point to Point or Hub and Spoke system on fuel burn, operating cost and revenue potential is highlighted. Fuel burn savings of 15% can be experienced with AAR over traditional refuelling operations, with point to point networks increasing the available seat miles (by approximately 20%) without a proportional increase in operating cost or fuel.

The Application of Digital Photogrammetric Techniques and Aerial Photography to the Preservation of Archaeological Detail. Case Study: The Copney Stone Circle Complex, Co. Tyrone, N. Ireland

The Copney Stone Circle Complex, Co. Tyrone, N. Ireland, is an important Bronze Age site forming part of the Mid-Ulster Stone Circle Complex. The Environment Service: Historic Monuments and Buildings (ESHMB) initiated a program of bog-clearance in August 1994 to excavate the stone circles. This work was completed by October 1994 and the excavated site was surveyed in August 1995. Almost immediately, the rate at which the stones forming the circles were breaking down was noted and a program of study initiated to make recommendations upon the conservation of this important site. Digital photogrammetric techniques were applied to aerial images of the stone circles and digital terrain models created from the images at a range of scales. These provide base data sets for comparison with identical surveys to be completed in successive years and will allow the rate of deterioration, and the areas most affected, of the circles to be determined. In addition, a 2D analysis of the stones provides an accurate analysis of the absolute 2D dimensions of the stones for rapid desktop computer analysis by researchers remote from the digital photogrammetric workstation used in the survey.

The products of this work are readily incorporated into web sites, educational packages and databases. The technique provides a rapid and user friendly method of presentation of a large body of information and measurements, and a reliable method of storage of the information from Copney should it become necessary to re-cover the site.

Breaking and Entering: Examining the role of stress and aerial exposure in predator-prey relationships between the common shore crab (Carcinus maenas) and cultivated blue mussels (Mytilus edulis).

During benthic cultivation Mytilus edulis (blue mussels) are subject to predation pressure from a number of predators including Carcinus maenas (shore crabs). This predator can be responsible for substantial losses of mussels from the fishery and a full understanding of the predator–prey relationship between M. edulis and C. maenas is required to ensure attempts that reduce predatory pressure and subsequent commercial loss are successful. Whilst much work has examined the prey–predator size relationships between C. maenas and M. edulis, far less research has investigated how stress, such as periods of extended aerial exposure, may affect these relationships. We tested whether profit in terms of calories gained by crabs consuming mussels stressed by aerial exposure for 48 h differed from that of mussels at ambient conditions and whether being stressed affected the mussel's likelihood of predation. We also tested whether the size relationship between predators and their prey differed when mussels were stressed. We found that the profitability of prey (calories gained per second of handling time) did not vary between stressed and unstressed mussels. Handling times for stressed and unstressed mussels were similar, even when crabs were presented with mussels of the maximum size that they are able to consume. Small crabs were more likely to reject a mussel of preferred size if it was unstressed, suggesting that crabs may be able to assess that these mussels would require extra effort to break into and consume. Our findings suggest that the predator–prey relationship between mussels and crabs is not altered when mussels are stressed. C. maenas remains a voracious predator and regardless of the condition of mussels laid on commercial beds there is a need to control this predator in attempt to reduce losses in the benthic fishery.

1967 Aerial View

View from above the tower during construction of the Thistle Complex.

1990 Aerial View

Aerial view of Brock University from around 1990.

Aerial view of the Chapman College campus, Orange, California, 1966

Aerial view of the Chapman College campus, Orange, California, 1966. Looking diagonally to the northeast. Corner of North Glassell Street and Palm Avenue in lower middle, with the five original buildings just beyond. The old gymnasium is by the oval playing field and stadium. Photographed by Rene Laursen, 702 N. Grand, Santa Ana, California [No. 1499#1].

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, February 23, 1973. Looking north; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 1330 Bristol S. E. #103 - Santa Ana, California 92707." [#9]

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, February 23, 1973. North at left; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 13

Aerial view of the Chapman College campus, Orange, California, 1973

Aerial view of the Chapman College campus, Orange, California, January, 1973. North at left; athletic field and stadium in center. Photographed by "Aerial Eye Inc. - Custom Aerial Photography - 1330 Palisades #92 - Santa Ana, California 92707." [#1]

Aerial view of the Chapman College residence halls, Orange, California

Aerial view of the Chapman College campus residence halls, Orange, California.

Aerial view of the Chapman College campus, Orange, California

Aerial view of the Chapman College campus, Orange, California. Looking northwest; the Moulton Fine Arts complex is at lower right. After 1978.

Aerial view of the Chapman College campus, Orange, California

Color postcard featuring an aerial view of the Chapman College campus, Orange, California, ca. 1995. Looking north. On message side: "Produced by Wayne Salvatti/Photografx; Copyright Photografx"

Aerial view of the Chapman College campus, Orange, California

Aerial view of the Chapman College campus, Orange, California, looking east. Memorial Hall is in the center, facing lawn and North Glassell Street.