September 11, 2001 Attacks Research Paper Example | Topics and Well Written Essays - 2000 words

September 11, 2001 Attacks - Research Paper Example Only after the towers collapsed and news of a similar attack on the Pentagon and an attempt on the White House did the magnitude of the events of September 11, 2001 begin to come into focus. A survey of the damages that would follow would inform of the severity of the September 11 2001 attacks. Those damages would reach beyond the immediate vicinity of the attacks and change our lives in many ways. This research studies analyzes the actual and general damages and consequences of the September 11, 2001 attacks. Actual Damages Al Qaeda’s terrorist attacks on the World Trade Center on September 2001 claimed the lives of almost 3000 persons and caused the area’s economy up to US$83 billion directly and indirectly in losses (Okuyama & Chang, 2011). The damages to New York City were particularly far-reaching since New York City represents the financial center of the US. In addition to property destruction, South Manhattan, is home to New York City’s government and inte rnational commerce. As a result of the attacks, the government and commercial activities were at a complete halt for weeks to come. Office buildings nearby were empty and New York’s subway system came to a complete halt. Thousands of New York residents living beyond Canal Street could not return home. New York’s schools and bridges were closed down (Tucker, 2004). For the entire country and for most of the world, the airline industry suffered the greatest losses. Airports were shut down on September 11 with passengers stranded near and far, putting airlines to the expense of housing passengers. Formal claims by the loved-ones of victims who died in the three crashes resulted in unprecedented insurance and litigation expenses for the airline industry. Airport security also cost the airline industry millions in implementation and administration expenses (Tucker, 2004). With buildings destroyed, transportation interruption and business closures, New York City â€Å"exper ienced massive job losses† (Tucker, 2004, p. 401). The damages to the Pentagon were less extensive but shocking all the same because the attack on the Pentagon symbolized an attack on the US as a whole. On the morning of September 11, 2001, a commercial airline deliberately crashed into the ground floor of the Pentagon claiming the lives of 65 passengers and 125 Pentagon occupants (Bangash, 2006). The ensuing fire caused serious but reparable damages to the building. Engineers have claimed that the strong reinforced columns of the Pentagon mitigated the actual damages (Bangash, 2006). The direct costs of searching for Osama bin Laden and infiltrating terror cells are immeasurable and are costs that will burden the US for years to come (Tucker, 2004). Thus the economic damages directly and indirectly resulting from the September 11, 2001 attacks are difficult to quantify. Thus one of the long lasting consequences of the September 11, 2001 attacks is the realization that economi c loss resulting from traumatic events are not only difficult to quantify but difficult to minimize (Jonkman et al, 2003). General Damages For the purpose of this research study, general damages refer to damages that are not specific and generally not quantifiable in terms of dollars and cents. These kinds of damages are better understood as collateral or consequential damages. It has been established that many persons who survived the attacks and witnessed the

Aircraft anti-skid System Certification and Regulation Research Paper

Aircraft anti-skid System Certification and Regulation - Research Paper Example It also maintains steering and aircraft stability in order to control the wheel from skidding which often the cause of aircraft accidents. Skidding of wheels in aircraft is closely monitored because of the many risks it takes when neglected. Skidding can reduce the braking efficiency which will result to locking of wheels, bursting of tyres and possible serious damage to the aircraft locked-up wheels. And these posed serious fear to pilots especially when taking off and landing. Aside from those ABS also reduces the chance of hydroplaning and helps eliminate excessive heat buildup. Hydroplaning is the loss of braking control or steering which usually happens when layer of water prevents direct contact between aircraft tires on the runway surface (Ming, et al., 2). The operation of the antiskid systems is generally armed by a switch in the cockpit. It has a squat switch which prevents current from flowing to the system during flight. The system only performs its function when the whee l deceleration indicates an impending skid. And ABS allows pilot to fully control over braking at speeds below 20 meters per hour (mph) (Mlevel3, 1). Tracing back the history of ABS, this system was purposely innovated for aircrafts since, it was impossible for aircraft to have threshold breaking. The initial concept of ABS was actually introduced by Gabriel Voisin, a French automobile and aircraft pioneer in 1929. The first aircraft ABS has utilized a flywheel, a rotating mechanical device that is used to store rotational energy, and a hydraulic line that feeds the brake cylinders. The flywheel has many advantages such when the energy source is not continuously available, it is exploited in the reciprocating engine to provide continuous energy. It also delivers energy at rates beyond the ability of an energy source and it controls the orientation. And it is also used to control orientation of a mechanical system especially when energy is transferred to or from the flywheel. The fir st flywheel was actually designed that runs with the similar speed as the wheel and was connected to a drum. The drum and the flywheel spin at the same speed in normal breaking. But, it leaves the flywheel spinning at a faster rate when the wheel and drum were to slow down which allows the valve to open. A small amount brake fluid then bypass the master cylinder down to a local reservoir which causes the pressure on the cylinder to decrease and release the brakes. The flywheel attached to the drum most important use was to open the valve when the wheel was rotating. This early concept of ABS system was noted to improve as least 30% of the breaking performance of the aircraft because it allows the pilots to find the skid point and enable them to apply breaks immediately. And, additional advantage, this system prevents the tires from burning or bursting (Flight, 587-588). Another revolution on the development of ABS took place at the beginning of Second World War. The new brake design was suitable for runway use which utilizes high-pressure hydraulic system associated with disc brakes and high-pneumatic tyres. The landing gears were also remodeled during this development era wherein it was stowed since the high aircraft speeds were already specified. And the wheels were made smaller in order to reduce the space available for brakes. Several brake rotor discs were also added which were placed side-by-side along the same axis with stators between each discs (Aircraft Technology Engineering & Maintenance, 2). Aircraft brake system (shown on Figure 1) commonly includes several important parts such as the normal brake system, which is powered by