Airports

The properties required by jet engines are linked to the combustion process particular to aviation engines. They must have an excellent cold behavior down to -50°C, a chemical composition which results in a low radiation flame that avoids carbon deposition on the walls, a low level of contaminants such as sediment, water and gums, in order to avoid problems during the airport storage and handling phase. 

Bioremediation also has the advantage that is can be relatively nonintmsive, and can sometimes be used ia situations where other approaches would be severely dismptive. For example, bioremediation has been used to clean up hydrocarbon spills under buildings, roads, and airport mnways without interfering with the continued use of these faciUties. 

P. O. Chelsau, ReHabihty Computation Using Fault Tree Analysis, TR32-1542, NASA, Airport, Md., 1971. 

Most architectural fabrics are usually flexible composites comprised of glass fibers coated with fluorocarbons to resist wind, mechanical forces, and outdoor environmental degradation. The airport terminal in Saudi Arabia, and the roofs for the Hubert Humphrey Dome in Minneapolis and the Tokyo Dome Stadium are a few examples of the successful use of architectural fabrics. 

X-ray fluoroscopy is used for direct on-line examination. A fluorescent screen is used to convert x-ray photons into visible light photons. A television camera receives the visible image and displays it on a television screen (see Fig. 19). This type of system is used for security screening of carry-on luggage at airports. 

Non-Newtonian antiicing fluids ate currently being used in the United States on a limited, experimental basis. Antiicing fluids requite special handling and appHcation equipment and techniques, and therefore deicing equipment modification and personnel training are requited before these fluids are used by an airline at an airport. 

Specifications for gas turbine fuels prescribe test limits that must be met by the refiner who manufactures fuel however, it is customary for fuel users to define quality control limits for fuel at the point of delivery or of custody transfer. These limits must be met by third parties who distribute and handle fuels on or near the airport. Tests on receipt at airport depots include appearance, distfllation, flash point (or vapor pressure), density, freezing point, smoke point, corrosion, existing gum, water reaction, and water separation. Tests on delivery to the aircraft include appearance, particulates, membrane color, free water, and electrical conductivity. 

The slope of the water solubiUty curves for fuels is about the same, and is constant over the 20—40°C temperature range. Each decrease of 1°C decreases water solubiUty about 3 ppm. The sensitivity of dissolved water to fuel temperature change is important. For example, the temperature of fuel generally drops as it is pumped iato an airport underground hydrant system because subsurface temperatures are about 10 °C lower than typical storage temperatures. This difference produces free water droplets, but these are removed by pumping fuel through a filter-coalescer and hydrophobic barrier before deUvery iato aircraft. 

The majority of refineries operated by petroleum companies in different parts of the world to make local products, such as gasoline and burner fuels, also produce jet fuels. Even a small refinery with simple equipment can make suitable jet fuel if it has access to the right cmde. However, the principal supply of both civil and military jet fuels is produced in large refineries. Many are located near major cities and airports and are frequentiy connected by pipeline directiy to the airport. Modem airports have extensive storage and handling faciUties operated by local authorities, petroleum companies or consortia, or the airlines themselves. 

NASA is also considering a more advanced aircraft such as Mach 5 to cut Pacific travel time to about three hours, but in this case kerosene fuel is no longer acceptable, and Hquefted natural gas or Hquefted hydrogen would be needed to provide the necessary cooling and stabiUty. However, a completely new fueling system would be required at every international airport to handle these cryogenic fluids. 

In November 1990 a fire occurred at a flammable liquid tank farm supporting Denver s Stapleton international airport. Eight of the farm s twelve storage tanks contained jet fuel, totaling almost 4.2 million gallons. The fire burned for 55 hours, destroying seven tanks. 

It is common practice to provide a standby emergency source of supply at all important installations such as large factories, railways, airports and other essential services. This is usually achieved with the use of a captive diesel generator (DG) set (Figure 16.1). Here we briefly discuss these machines, their characteristics and selection for a required application. We also consider schemes that are commonly used to start a DG set and run it individually or in parallel with an existing source of supply, which may be another DG set or an infinite bus. 

Fig. 14.1. Before it broke, this steel bolt held o seat onto its mounting at Milan airport. Whenever someone sat down, the lower part of the cross-section went into tension, causing a crack to grow there by metal fatigue (Chapter 15 crack No. 1). When someone got up again, the upper part went into tension, causing fatigue crack No. 2 to grow. Eventually the bolt failed by fast fracture from the larger of the two fatigue cracks. The victim was able to escape with the fractured bolt ...

Average airport visibilities over the eastern half of the United States have been determined over a period of approximately 25 years (1948-1974) (6). Although seasonal variations occur, the long-term trend has been decreased visual air quality over the time period. 

Holzworth and Maga (16) developed a technique for examining the trend in visibility and analyzed data for several California airports. Bakersfield s visibility deteriorated over the period 1948-1957, and Sacramento s visibility decreased over the period 1935-1958. Los Angeles had decreasing visibility from 1932 to 1947, with little change over the period 1948-1959. 

Compare visibility measurements at a nearby airport with those of particle-free clean air. 

Flexibility, judgment large existing data base (airport visual range)... 

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